Question 1
Typical rheumatoid arthritis is characterized by
Symmetric inflammatory polyarthritis
Sparing of axial skeleton except cervical spine
Sparing of distal interphalangeal joints
All of the above--------------
Question 2
Which of these is not a feature of rheumatoid arthritis?
Swollen joints
Painful joints
Morning stiffness
Headache---------------
Question 3
The exact etiology of rheumatoid arthritis is not known but all the following have been implicated as having a role in its causation ,except
Genetic factors
Autoimmunity
Microbial infection
Low calcium levels in the body-----------
Question 4
Rheumatoid arthritis is a mutisystem disorder. It can involve any of the following, except
Eyes
Lungs
Heart
Ear---------------
Question 5
What is true regarding the prevalence of rheumatoid arthritis?
More common in females but difference reduces in older age group-------------
More common in females but difference is less in younger age group
More common in males but difference reduces in older age group
More common in males but difference is less in younger age group
Question 6
Rheumatoid factors are autoantibodies found in many individuals. Their importance in rheumatoid arthritis is as a
Prognostic factor---------------
Screening factor
Diagnostic factor
None of the above
Question 7
Features that signify a bad prognosis in rheumatoid arthritis are
High titer of rheumatoid factor
Presence of subcutaneous nodules
Radiographic evidence of erosion at the time of initial evaluation
All of the above----------------
Question 8
The goals of therapy of rheumatoid arthritis are
Reduction of pain and inflammation
Maintenance of function and movement
Control of systemic involvement
All of the above-------------
Question 9
NSAID are used as the first line of treatment for rheumatoid arthritis because of their
Anti-inflammatory properties----------
Immunosuppresive properties
Cytotoxic properties
Tumor necrosis factor inhibitor properties
Question 10
The newly discovered COX-2 inhibitors are considered superior to standard NSAID because they have
Less gastro-intestinal side effects------------
Minimal renal toxicity
Slow the progress of the disease
None of the above
Question 11
Corticosteroids used for management of rheumatoid arthritis have all these properties, except
Reduce inflammation and swelling
Beneficial for systemic involvement in rheumatoid arthritis
Can be taken orally or as an injection
Delayed onset of action----------------
Question 12
DMARDs are a group of diverse agents that slow down the progress of rheumatoid arthritis. All is true with regard to DMARDs, except
Benefit is noticed after 2-6 months
These are generally prescribed along with NSAID or steroids
Work by slowing the immune system from attacking the joint
None of these are used for treating disorders other than rheumatoid arthritis----------------
Question 13
Leflunomide is a newly approved DMARD. It should not be prescribed to
Elderly men
Children
Pregnant women-----------
Elderly women
Question 14
Biologic response modifiers are drugs that target the immune factors, particularly Tumor Necrosis Factor (TNF) which play a major role in the destructive process. Which of these drugs belong to this class of drugs?
Etanercept------------
Celecoxib
Rofecoxib
Penicillamine
Question 15
Agents that are being studied for benefits in rheumatoid arthritis are
Soluble collagen
Thalidomide
Protease inhibitors
All the above-----------------
Saturday, January 12, 2008
63 - rheumatoid arthritis mcqs
Saturday, January 5, 2008
62 - orthopedics mcqs - 171 to 180 - bone pathology
Question 171
A 49-year-old woman has noted increasing difficulty with movement of her left hand for the past 2 years. On examination she cannot completely extend the left middle finger. In the palm of her hand at the base of this finger there is an ill-defined mass that is very firm to palpation. What will microscopic examination of this excised mass most likely show?
A Fibromatosis
B Rhabdomyosarcoma
C Granulomatous inflammation
D Dystrophic calcification
E Giant cell tumor of tendon sheath
---------------------------------------------
(A) CORRECT. This is a so-called Dupuytren contracture due to a palmar fibromatosis. The etiology is obscure.
(B) Incorrect. In adults, these tumors are uncommon and appear as large masses in deep soft tissues.
(C) Incorrect. A foreign body granuloma could occur at this site, but would not likely lead to a contracture of one finger.
(D) Incorrect. This would not lead to a marked contracture.
(E) Incorrect. This appears as a more well-circumscribed mass without contracture.
----------------------------------------------------
Question 172
A 45-year-old woman notices that she develops tingling and numbness over the palmar surface of her thumb, index, and middle fingers after several hours at her computer workstation doing word processing. Pain in the same area often occurs at night as well. On physical examination she has minimal atrophy of thenar muscles of both hands. Which of the following conditions is most likely to account for her symptoms?
A Toxic peripheral neuropathy
B Rheumatoid arthritis
C Gout
D Hypertrophic osteoarthropathy
E Diabetes mellitus
F Localized tenosynovitis
--------------------------
(F) CORRECT. She has carpal tunnel syndrome, an entrapment neuropathy of the median nerve. In middle-aged women, tenosynovitis is often present, worsened by repetitive motion.
(A) Incorrect. The neuropathy she has is too localized to suggest a toxic etiology.
(B) Incorrect. Rheumatoid arthritis leads to pain, but not in a localized area in median nerve distribution.
(C) Incorrect. Gout may lead to tophaceous deposits, but over bony prominences, not median nerve.
(D) Incorrect. Hypertrophic osteoarthropathy is characterized by clubbing of the digits as well as arthritis. It is most often associated with cardiorespiratory diseases such as chronic obstructive pulmonary disease.
(E) Incorrect. Though diabetes mellitus may result in peripheral neuropathy, such a diabetic neuropathy is unlikely to be so localized as in this case, and unlikely to be related to repetitive motion.
------------------------------------------------------
Question 173
A 55-year-old woman has a 15 year history of poorly controlled diabetes mellitus. She develops increasing bone pain in her extremities over the past 4 months. On physical examination there are no abnormal findings. A radiograph of the hand shows osteitis fibrosa cystica of the metacarpals. Laboratory studies show a serum urea nitrogen of 65 mg/dL and serum creatinine of 7.0 mg/dL. Which of the following pathologic abnormalities is she most likely to have?
A Chondrocalcinosis
B Hyperparathyroidism
C Multiple myeloma
D Osteochondromatosis
E Osteopetrosis
------------------------------------------------
(B) CORRECT. In secondary hyperparathyroidism, the parathyroid glands are hyperplastic. The renal failure impairs renal phosphate excretion, leading to hyperphosphatemia, which depresses the serum calcium and turns on parathyroid hormone production, leading to renal osteodystrophy.
(A) Incorrect. Chondrocalcinosis affecting joints is not related to diabetes mellitus or renal failure.
(C) Incorrect. Multiple myeloma may produce renal failure. The bone lesions are characteristically lytic.
(D) Incorrect. Osteochondromatosis leads to multiple bony exostoses; it is unrelated to diabetes mellitus or renal failure.
(E) Incorrect. Osteopetrosis is rare and unlikely to occur with chronic renal failure or diabetes mellitus.
--------------------------------------
Question 174
A 45-year-old man has noted pain in his right knee for the past 5 years. As he moves about during the day, the pain decreases. On physical examination there is no joint swelling, warmth, or erythema, but he does have decreased range of motion. Which of the following conditions is he most likely to have?
A Osteoporosis
B Osteochondroma
C Osteomalacia
D Osteoarthritis
E Osteopetrosis
-------------------------------------------
(D) CORRECT. Osteoarthritis often involves a larger, weight-bearing joint. The pain usually diminishes with movement, but recurs with reuse or prolonged use of the affected joint.
(A) Incorrect. Osteoporosis would be uncommon in a 45-year-old man. Back pain is a more typical symptom for osteoporosis.
(B) Incorrect. This mass lesion could be located about the knee, but the pain would probably be exacerbated by movement or local trauma.
(C) Incorrect. The findings with osteomalacia would be similar to osteoporosis, and back pain would be more typical.
(E) Incorrect. This uncommon inherited metabolic disorder leads to 'brittle bones' that predispose to fractures.
-----------------------------------------
Question 175
As he continues to age, a 50-year-old man is bothered by slowly progressive loss of mobility of his spine at the hips since the age of 25. He has a brother who is similarly affected. On physical examination there is loss of lumbar lordosis with decreased range of motion at his hips. Which of the following pathologic abnormalities involving his sacroiliac joints is most likely to be present?
A Ankylosis
B Gummatous necrosis
C Mosaic growth pattern
D Osteonecrosis
E Pannus formation
--------------------------------------------------
(A) CORRECT. The hereditary nature of ankylosing spondylitis means that about one-fourth of close relatives have the disease. Bony ankylosis of the sacroiliac joint is a common outcome in a patient who has had ankylosing spondylitis for years.
(B) Incorrect. Gummatous necrosis is a feature of tertiary syphilitic involvement of bone, which is most often knees.
(C) Incorrect. A mosaic pattern of osteolysis and osteosclerosis is characteristic for Paget disease of bone, which is more common in older persons and does not have a hereditary pattern.
(D) Incorrect. Osteonecrosis can be seen with ischemia and infection.
(E) Incorrect. Pannus formation is characteristic for rheumatoid arthritis, which most often affects the small joints of hands and feet first.
------------------------------------------------
Question 176
A 10-year-old girl has complained of joint pain for the past 2 years. The pain is localized to her knees and ankles; it occurs either with or without movement. The arthralgias are accompanied by fever. On physical examination she has a temperature of 37.8 C. There is no deformity of her knees. She has generalized lymphadenopathy. Which of the following is the most likely diagnosis?
A Gonococcal arthritis
B Ankylosing spondylitis
C Juvenile rheumatoid arthritis
D Tuberculous arthritis
E Gout
------------------------------------------------
(C) CORRECT. Also known as Still disease, JRA is not frequent. About 5% of rheumatoid arthritis cases occur in persons <16>
(A) Incorrect. Gonococcal arthritis is a suppurative arthritis, and it is seen most often in young persons as a complication of gonorrheal infection.
(B) Incorrect. Ankylosing spondylitis typically involves the spine. It is slowly progressive, beginning in the 3rd decade, and does not have a febrile component or lymphadenopathy.
(D) Incorrect. Tuberculous arthritis is a complication of adjacent osteomyelitis or dissemination. It is destructive and monoarticular, usually involving the spine.
(E) Incorrect. Gouty arthritis usually involves the big toe of males with hyperuricemia who are past the third decade.
------------------------------------------------
Question 177
A pathologic study is performed involving patients with a history of arthritis. These patients had femoral heads submitted to surgical pathology following resection and placement of hip prostheses. The pathologic findings observed by microscopic examination of these specimens are analyzed. Which of the following findings is most likely to be seen with the greatest frequency in these patients?
A Loss of articular hyaline cartilage
B Synovitis
C Underlying osteomyelitis of bone
D Bone marrow fibrosis
E Crystal deposition
-------------------------------------------------
(A) CORRECT. Osteoarthritis is very common. The articular surface becomes worn or damaged with time, leading to pain and loss of mobility
(B) Incorrect. Chronic inflammation is more a feature of rheumatoid arthritis, which is less common than osteoarthritis.
(C) Incorrect. Osteomyelitis is not frequent and arthritis is not a common association.
(D) Incorrect. Although fibrosis of adjacent marrow beneath the articular cartilage may occur, it is of no major importance -- most hematopoiesis is in vertebra, ribs and sternum.
(E) Incorrect. Gouty arthritis with sodium urate deposition and 'pseudogout' with calcium pyrophosphate deposition are not nearly as common as osteoarthritis.
-----------------------------------------------------
Question 178
An epidemiologic study is performed with data entered into the hospital tumor registry for subjects who were diagnosed with bone tumors. Which of the following primary neoplasms of bone is most likely to be present in an older adult, rather than in a child or young adult?
A Osteosarcoma
B Chondrosarcoma
C Ewing sarcoma
D Giant cell tumor
E Osteoid osteoma
----------------------------------------------------
(B) CORRECT. Chondrosarcomas occur over a wide age range. Many arise in older adults. The 'secondary' forms that follow enchondromatosis appear later in life.
(A) Incorrect. Osteosarcomas are more likely to appear in the first to third decades of life. Some, however, are 'secondary' and appear in older persons with Paget disease of bone.
(C) Incorrect. Ewing sarcomas usually occur in the first two decades of life.
(D) Incorrect. Most giant cell tumors occur in women between the ages of 20 and 40.
(E) Incorrect. This painful lesion appears in the first three decades of life, more often in males.
----------------------------------------------------
Question 179
A 71-year-old man dies from pneumonia. Laboratory studies prior to death showed a serum alkaline phosphatase of 289 U/L, total protein 6.0 g/dL, albumin 3.8 g/dL, calcium 12.9 mg/dL, and phosphorus 3.6 mg/dL. At autopsy multiple firm white irregular mass lesions are scattered throughout his vertebrae. Which of the following is the most likely diagnosis?
A Metastatic carcinoma of prostate
B Osteochondromatosis
C Ewing sarcoma
D Fibrous dysplasia of bone
E Osteomalacia
--------------------------------------------------
(A) CORRECT. An elevated serum alkaline phosphatase in an older adult is a red flag for metastatic carcinoma to bone.
(B) Incorrect. Osteochondromatosis is rare. Osteochondromas are exostoses of bone.
(C) Incorrect. Ewing sarcoma is seen in children and young adults, typically in the diaphyseal region of long bones.
(D) Incorrect. Fibrous dysplasia is uncommon disorder of bone maturation that leads to bone deformity with fracture.
(E) Incorrect. Vitamin D deficiency in adults can lead to decreased bone mineralization with an appearance similar to osteoporosis.
------------------------------------------------
Question 180
A 30-year-old man has pain about his left knee that he says has been worsening "for weeks". On physical examination the left knee appears larger than the right, and there is tenderness to palpaption. A radiograph reveals a 7 cm lytic lesion involving the epiphyseal region of the distal femur with a "soap bubble" appearance. The lesion is curretted, and histologically there are numerous multinucleated cells in a stroma with plump to spindle shaped mononuclear cells. Which of the following is the most likely diagnosis?
A Osteosarcoma
B Chondrosarcoma
C Malignant fibrous histiocytoma
D Giant cell tumor
E Tuberculosis
-------------------------------------------------
(D) CORRECT. A giant cell tumor of bone typically arises in the epiphysis.
(A) Incorrect. Osteosarcoma is usually seen in the metaphyseal region and destroys cortex of bone. Very atypical cells with osteoid production are seen microscopically.
(B) Incorrect. Chondrosarcomas have atypical chondrocytes with cartilagenous matrix. They often form a bulky mass without distinct borders.
(C) Incorrect. An MFH is a sarcoma that may arise in bone and lead to destruction with erosion of bone.
(E) Incorrect. Tuberculosis leads to a chronic osteomyelitis with bone destruction and remodelling.
A 49-year-old woman has noted increasing difficulty with movement of her left hand for the past 2 years. On examination she cannot completely extend the left middle finger. In the palm of her hand at the base of this finger there is an ill-defined mass that is very firm to palpation. What will microscopic examination of this excised mass most likely show?
A Fibromatosis
B Rhabdomyosarcoma
C Granulomatous inflammation
D Dystrophic calcification
E Giant cell tumor of tendon sheath
---------------------------------------------
(A) CORRECT. This is a so-called Dupuytren contracture due to a palmar fibromatosis. The etiology is obscure.
(B) Incorrect. In adults, these tumors are uncommon and appear as large masses in deep soft tissues.
(C) Incorrect. A foreign body granuloma could occur at this site, but would not likely lead to a contracture of one finger.
(D) Incorrect. This would not lead to a marked contracture.
(E) Incorrect. This appears as a more well-circumscribed mass without contracture.
----------------------------------------------------
Question 172
A 45-year-old woman notices that she develops tingling and numbness over the palmar surface of her thumb, index, and middle fingers after several hours at her computer workstation doing word processing. Pain in the same area often occurs at night as well. On physical examination she has minimal atrophy of thenar muscles of both hands. Which of the following conditions is most likely to account for her symptoms?
A Toxic peripheral neuropathy
B Rheumatoid arthritis
C Gout
D Hypertrophic osteoarthropathy
E Diabetes mellitus
F Localized tenosynovitis
--------------------------
(F) CORRECT. She has carpal tunnel syndrome, an entrapment neuropathy of the median nerve. In middle-aged women, tenosynovitis is often present, worsened by repetitive motion.
(A) Incorrect. The neuropathy she has is too localized to suggest a toxic etiology.
(B) Incorrect. Rheumatoid arthritis leads to pain, but not in a localized area in median nerve distribution.
(C) Incorrect. Gout may lead to tophaceous deposits, but over bony prominences, not median nerve.
(D) Incorrect. Hypertrophic osteoarthropathy is characterized by clubbing of the digits as well as arthritis. It is most often associated with cardiorespiratory diseases such as chronic obstructive pulmonary disease.
(E) Incorrect. Though diabetes mellitus may result in peripheral neuropathy, such a diabetic neuropathy is unlikely to be so localized as in this case, and unlikely to be related to repetitive motion.
------------------------------------------------------
Question 173
A 55-year-old woman has a 15 year history of poorly controlled diabetes mellitus. She develops increasing bone pain in her extremities over the past 4 months. On physical examination there are no abnormal findings. A radiograph of the hand shows osteitis fibrosa cystica of the metacarpals. Laboratory studies show a serum urea nitrogen of 65 mg/dL and serum creatinine of 7.0 mg/dL. Which of the following pathologic abnormalities is she most likely to have?
A Chondrocalcinosis
B Hyperparathyroidism
C Multiple myeloma
D Osteochondromatosis
E Osteopetrosis
------------------------------------------------
(B) CORRECT. In secondary hyperparathyroidism, the parathyroid glands are hyperplastic. The renal failure impairs renal phosphate excretion, leading to hyperphosphatemia, which depresses the serum calcium and turns on parathyroid hormone production, leading to renal osteodystrophy.
(A) Incorrect. Chondrocalcinosis affecting joints is not related to diabetes mellitus or renal failure.
(C) Incorrect. Multiple myeloma may produce renal failure. The bone lesions are characteristically lytic.
(D) Incorrect. Osteochondromatosis leads to multiple bony exostoses; it is unrelated to diabetes mellitus or renal failure.
(E) Incorrect. Osteopetrosis is rare and unlikely to occur with chronic renal failure or diabetes mellitus.
--------------------------------------
Question 174
A 45-year-old man has noted pain in his right knee for the past 5 years. As he moves about during the day, the pain decreases. On physical examination there is no joint swelling, warmth, or erythema, but he does have decreased range of motion. Which of the following conditions is he most likely to have?
A Osteoporosis
B Osteochondroma
C Osteomalacia
D Osteoarthritis
E Osteopetrosis
-------------------------------------------
(D) CORRECT. Osteoarthritis often involves a larger, weight-bearing joint. The pain usually diminishes with movement, but recurs with reuse or prolonged use of the affected joint.
(A) Incorrect. Osteoporosis would be uncommon in a 45-year-old man. Back pain is a more typical symptom for osteoporosis.
(B) Incorrect. This mass lesion could be located about the knee, but the pain would probably be exacerbated by movement or local trauma.
(C) Incorrect. The findings with osteomalacia would be similar to osteoporosis, and back pain would be more typical.
(E) Incorrect. This uncommon inherited metabolic disorder leads to 'brittle bones' that predispose to fractures.
-----------------------------------------
Question 175
As he continues to age, a 50-year-old man is bothered by slowly progressive loss of mobility of his spine at the hips since the age of 25. He has a brother who is similarly affected. On physical examination there is loss of lumbar lordosis with decreased range of motion at his hips. Which of the following pathologic abnormalities involving his sacroiliac joints is most likely to be present?
A Ankylosis
B Gummatous necrosis
C Mosaic growth pattern
D Osteonecrosis
E Pannus formation
--------------------------------------------------
(A) CORRECT. The hereditary nature of ankylosing spondylitis means that about one-fourth of close relatives have the disease. Bony ankylosis of the sacroiliac joint is a common outcome in a patient who has had ankylosing spondylitis for years.
(B) Incorrect. Gummatous necrosis is a feature of tertiary syphilitic involvement of bone, which is most often knees.
(C) Incorrect. A mosaic pattern of osteolysis and osteosclerosis is characteristic for Paget disease of bone, which is more common in older persons and does not have a hereditary pattern.
(D) Incorrect. Osteonecrosis can be seen with ischemia and infection.
(E) Incorrect. Pannus formation is characteristic for rheumatoid arthritis, which most often affects the small joints of hands and feet first.
------------------------------------------------
Question 176
A 10-year-old girl has complained of joint pain for the past 2 years. The pain is localized to her knees and ankles; it occurs either with or without movement. The arthralgias are accompanied by fever. On physical examination she has a temperature of 37.8 C. There is no deformity of her knees. She has generalized lymphadenopathy. Which of the following is the most likely diagnosis?
A Gonococcal arthritis
B Ankylosing spondylitis
C Juvenile rheumatoid arthritis
D Tuberculous arthritis
E Gout
------------------------------------------------
(C) CORRECT. Also known as Still disease, JRA is not frequent. About 5% of rheumatoid arthritis cases occur in persons <16>
(A) Incorrect. Gonococcal arthritis is a suppurative arthritis, and it is seen most often in young persons as a complication of gonorrheal infection.
(B) Incorrect. Ankylosing spondylitis typically involves the spine. It is slowly progressive, beginning in the 3rd decade, and does not have a febrile component or lymphadenopathy.
(D) Incorrect. Tuberculous arthritis is a complication of adjacent osteomyelitis or dissemination. It is destructive and monoarticular, usually involving the spine.
(E) Incorrect. Gouty arthritis usually involves the big toe of males with hyperuricemia who are past the third decade.
------------------------------------------------
Question 177
A pathologic study is performed involving patients with a history of arthritis. These patients had femoral heads submitted to surgical pathology following resection and placement of hip prostheses. The pathologic findings observed by microscopic examination of these specimens are analyzed. Which of the following findings is most likely to be seen with the greatest frequency in these patients?
A Loss of articular hyaline cartilage
B Synovitis
C Underlying osteomyelitis of bone
D Bone marrow fibrosis
E Crystal deposition
-------------------------------------------------
(A) CORRECT. Osteoarthritis is very common. The articular surface becomes worn or damaged with time, leading to pain and loss of mobility
(B) Incorrect. Chronic inflammation is more a feature of rheumatoid arthritis, which is less common than osteoarthritis.
(C) Incorrect. Osteomyelitis is not frequent and arthritis is not a common association.
(D) Incorrect. Although fibrosis of adjacent marrow beneath the articular cartilage may occur, it is of no major importance -- most hematopoiesis is in vertebra, ribs and sternum.
(E) Incorrect. Gouty arthritis with sodium urate deposition and 'pseudogout' with calcium pyrophosphate deposition are not nearly as common as osteoarthritis.
-----------------------------------------------------
Question 178
An epidemiologic study is performed with data entered into the hospital tumor registry for subjects who were diagnosed with bone tumors. Which of the following primary neoplasms of bone is most likely to be present in an older adult, rather than in a child or young adult?
A Osteosarcoma
B Chondrosarcoma
C Ewing sarcoma
D Giant cell tumor
E Osteoid osteoma
----------------------------------------------------
(B) CORRECT. Chondrosarcomas occur over a wide age range. Many arise in older adults. The 'secondary' forms that follow enchondromatosis appear later in life.
(A) Incorrect. Osteosarcomas are more likely to appear in the first to third decades of life. Some, however, are 'secondary' and appear in older persons with Paget disease of bone.
(C) Incorrect. Ewing sarcomas usually occur in the first two decades of life.
(D) Incorrect. Most giant cell tumors occur in women between the ages of 20 and 40.
(E) Incorrect. This painful lesion appears in the first three decades of life, more often in males.
----------------------------------------------------
Question 179
A 71-year-old man dies from pneumonia. Laboratory studies prior to death showed a serum alkaline phosphatase of 289 U/L, total protein 6.0 g/dL, albumin 3.8 g/dL, calcium 12.9 mg/dL, and phosphorus 3.6 mg/dL. At autopsy multiple firm white irregular mass lesions are scattered throughout his vertebrae. Which of the following is the most likely diagnosis?
A Metastatic carcinoma of prostate
B Osteochondromatosis
C Ewing sarcoma
D Fibrous dysplasia of bone
E Osteomalacia
--------------------------------------------------
(A) CORRECT. An elevated serum alkaline phosphatase in an older adult is a red flag for metastatic carcinoma to bone.
(B) Incorrect. Osteochondromatosis is rare. Osteochondromas are exostoses of bone.
(C) Incorrect. Ewing sarcoma is seen in children and young adults, typically in the diaphyseal region of long bones.
(D) Incorrect. Fibrous dysplasia is uncommon disorder of bone maturation that leads to bone deformity with fracture.
(E) Incorrect. Vitamin D deficiency in adults can lead to decreased bone mineralization with an appearance similar to osteoporosis.
------------------------------------------------
Question 180
A 30-year-old man has pain about his left knee that he says has been worsening "for weeks". On physical examination the left knee appears larger than the right, and there is tenderness to palpaption. A radiograph reveals a 7 cm lytic lesion involving the epiphyseal region of the distal femur with a "soap bubble" appearance. The lesion is curretted, and histologically there are numerous multinucleated cells in a stroma with plump to spindle shaped mononuclear cells. Which of the following is the most likely diagnosis?
A Osteosarcoma
B Chondrosarcoma
C Malignant fibrous histiocytoma
D Giant cell tumor
E Tuberculosis
-------------------------------------------------
(D) CORRECT. A giant cell tumor of bone typically arises in the epiphysis.
(A) Incorrect. Osteosarcoma is usually seen in the metaphyseal region and destroys cortex of bone. Very atypical cells with osteoid production are seen microscopically.
(B) Incorrect. Chondrosarcomas have atypical chondrocytes with cartilagenous matrix. They often form a bulky mass without distinct borders.
(C) Incorrect. An MFH is a sarcoma that may arise in bone and lead to destruction with erosion of bone.
(E) Incorrect. Tuberculosis leads to a chronic osteomyelitis with bone destruction and remodelling.
61 - orthopedics mcqs - 161 - 170 - bone pathology
Question 161
A clinical study is performed with subjects who have been diagnosed with a primary bone lesion. The demographic data for these subjects is analyzed. Which of the following bone diseases is most likely to be found to have a female predominance?
A Aneurysmal bone cyst
B Osteosarcoma
C Chondrosarcoma
D Ewing sarcoma
E Osteochondroma
---------------------------------------
(A) CORRECT. Most bone lesions (and the worst ones) have a male predominance.
(B) Incorrect. Primary malignant tumors of bone have a male predominance.
(C) Incorrect. Primary malignant tumors of bone have a male predominance.
(D) Incorrect. Primary malignant tumors of bone have a male predominance.
(E) Incorrect. Primary malignant tumors of bone have a male predominance.
----------------------------------------
Question 162
A 21-year-old college student has noted increasing pain and soreness in his left shoulder after a summer working on the ranch and bucking bales of hay (heavy lifting and turning motions) while at a ranch up in the Cache Valley. On physical examination he can hardly adduct his left arm to the level of his shoulder. An aspiration of the subacromial region is performed and clear fluid is obtained. Which of the following is the most likely diagnosis?
A Tenosynovitis
B Costochondritis
C Bursitis
D Ganglion cyst
E Pseudogout
-------------------------------------------
(C) CORRECT. Synovial-lined bursal sacs become inflamed and distended with watery fluid, more often in males engaging in excessive manual labor or exercise.
(A) Incorrect. Inflammation of the tendon sheath is more common in the wrists and hands.
(B) Incorrect. Costochondral junctions of ribs are present in the anterior chest.
(D) Incorrect. These cysts in the connective tissue of a tendon sheath or joint capsule are usually seen in the wrist.
(E) Incorrect. Deposition of calcium pyrophosphate crystals in pseudogout is more typical of persons over age 50 and usually involves the knee.
-------------------------------------------
Question 163
Over the past 4 days, an 18-year-old man has developed marked pain and swelling in his right hip that makes movement difficult. He has no history of major medical problems. On physical examination there is pain on movement with diminished range of motion of the hip. A joint aspirate from the hip reveals cloudy fluid that on microscopic examination shows numerous neutrophils but no crystals. Which of the following conditions is most likely to have preceded development of his hip problem?
A Gonococcal urethritis
B Sickle cell anemia
C Rheumatoid arthritis
D Systemic lupus erythematosus
E Erythema chronicum migrans
---------------------------------------------------------
(A) CORRECT. Neisseria gonorrheae infection can produce an acute arthritis. A gram stain of a joint aspirate may show many neutrophils with intracellular gram-negative diplococci.
(B) Incorrect. Sickle cell anemia may be associated with osteomyelitis due to Salmonella organisms, but this is rare.
(C) Incorrect. Small joints (such as the hand) are more likely to be involved than large joints (such as the hip) with rheumatoid arthritis. There is proliferative synovitis with lymphocytes and plasma cells.
(D) Incorrect. Autoimmune diseases such as systemic lupus erythematosus are often associated with arthralgias, but there is minimal actual joint inflammation and typically no deformity.
(E) Incorrect. The arthritis of Lyme disease is often seen in stages II or III and is not typically purulent.
---------------------------------------------------
Question 164
A social worker refers a 2-year-old child to the physician because of suspected child abuse. On physical examination, the child has blue sclerae, diminished hearing in both ears, and misshapen teeth. There are no external contusions or lacerations of the skin. Radiographs of the child's extremities show recent and healing long bone fractures. Which of the following is the most likely diagnosis?
A Extensive trauma ("shaken child syndrome")
B Osteogenesis imperfecta
C Achondroplasia
D Rickets
E Osteopetrosis
----------------------------------------------------
(B) CORRECT. This is a disorder of type 1 collagen synthesis, with subsequent risk for fractures of bone. The blue sclerae, hearing loss, and dental abnormalities are characteristic for OI.
(A) Incorrect. Don't make the mistake of assuming all fractures are due to trauma.
(C) Incorrect. Achondroplasia is a form of dwarfism, but it is not characterized by fractures.
(D) Incorrect. The bones in a growing child with rickets will be deformed, but extensive fractures are not common.
(E) Incorrect. This rare condition (Albers-Schonberg disease) is a hereditary defect in osteoclast function with markedly thickened, sclerotic bone that fractures readily.
-------------------------------------------------------------------
Question 165
A 23-year-old G2 P1 woman has noted minimal fetal movement at 18 weeks gestation. An ultrasound scan shows that the fetal limbs are shortened. At 30 weeks gestation a stillborn fetus is delivered. A postmortem radiograph reveals extensive long bone, rib, and pelvic fractures. Autopsy reveals a normal appearance to internal organs. A mutation involving a gene encoding for which of the following proteins is most likely to produce these findings?
A Fibrillin
B Fibroblast growth factor receptor 3
C Retinoblastoma
D Neurofibromin
E Type I collagen
-----------------------------------------------------
(E) CORRECT. Osteogenesis imperfecta is an inherited disorder (usually autosomal recessive) of type I collagen synthesis. This is OI type II, the perinatal lethal form..
(A) Incorrect. Mutations of the fibrillin gene are present with Marfan syndrome, which affects the connective tissue of the cardiovascular system most severely.
(B) Incorrect. The FGFR gene mutations are associated with skeletal dysplasias, such as achondroplasia, that are not usually accompanied by fractures.
(C) Incorrect. The Rb gene is a tumor suppressor gene. If both copies of the gene are mutated, then the risk for malignancy is increased. One of the malignancies that can occur is osteosarcoma.
(D) Incorrect. NF1 can be associated with bone deformities beginning in childhood as a consequence of growth of neurofibromas.
----------------------------------------------------------
Question 166
A 41-year-old previously healthy man has had backache with muscle spasms, weakness, and pain felt in the right hip radiating all the way to his toes for the past 8 months. He does not have headaches or other neurologic problems. Physical examination reveals that the circumference of his right leg is smaller than the left, and he has paresthesias in an L5 distribution in the right leg. Which of the following conditions is he most likely to have?
A Spondylolisthesis
B Spina bifida
C Herniated nucleus pulposus
D Osteoporosis
E Paget disease of bone
--------------------
(C) CORRECT. He has a herniated intervertebral disk in which impingement on spinal nerve roots (usually L5 or S1) produces sensory and motor disturbances.
(A) Incorrect. In this disorder, the vertebral body, pedicles, and facets 'slips' forward to produce back pain, and limited motion. Symptoms are often bilateral.
(B) Incorrect. This is a failure of fusion of the laminae of the neural arch and is usually occult until an injury or radiograph reveals it.
(D) Incorrect. Osteoporosis at his age and in a male is unlikely. Compressed vertebral fractures may involve nerve roots, but are not as likely as a herniated disk.
(E) Incorrect. This is unlikely at his age. Paget is often painless, but if advanced, a nerve root may become entrapped.
-----------------------------
Question 167
A 5-year-old child has complained of pain on the left side of his head for 3 weeks. There are no abnormal findings on physical examination. A skull radiograph reveals a solitary destructive bony lesion of the left mastoid region. A biopsy is performed and microscopic examination shows that this lesion is composed histologically of a mixed inflammatory cell infiltrate. Which of the following is the most likely diagnosis?
A Osteoid osteoma
B Letterer-Siwe syndrome
C Eosinophilic granuloma
D Osteitis fibrosa cystica
E Tuberculosis
-----------------------------------
(C) CORRECT. Eosinophilic granulomas are a localized form of Langerhans cell histiocytosis that can be found in skull or long bones and can mimic osteomyelitis. The mixed inflammatory cell infiltrated can have histiocytes, eosinophils, plasma cells, and lymphocytes.
(A) Incorrect. This lesion has a central nidus surrounded by sclerotic bone.
(B) Incorrect. This disseminated form of Langerhans cell histiocytosis most often occurs in children under 3.
(D) Incorrect. This localized bone lesion occurs most often in patients with hyperparathyroidism.
(E) Incorrect. Epithelioid macrophages and Langhans giant cells should be present in a granuloma with M. tuberculosis.
--------------------------------------
Question 168
A 49-year-old man has complained of episodes of joint pain for over 10 years. This pain has occurred in a remitting and relapsing pattern. On physical examination there are deformities of his hands involving the fingers, with swan-neck deformities and ulnar deviation. His condition improves following corticosteroid and gold therapy. Which of the following serologic tests is most likely to be positive in this man?
A Rapid plasma reagin
B HLA-B27
C Anti-double stranded DNA
D Rheumatoid factor
E Borrelia burgdorferi
------------------------
(D) CORRECT. Joint deformity frequently occurs with chronic rheumatoid arthritis. Females are affected more than males, and pregnancy may lessen the severity of the disease. However, men can get RA.
(A) Incorrect. The RPR is a screening test for syphilis. Gummatous necrosis in tertiary syphilis may involve large joints such as the knees..
(B) Incorrect. HLA-B27 is often positive in ankylosing spondylitis which involves the spine.
(C) Incorrect. The anti-double stranded DNA positivity is most specific for systemic lupus erythematosus, which is unlikely to be complicated by joint deformity.
(E) Incorrect. Ankylosis can and does occur often with severe rheumatoid arthritis.
--------------------------------
Question 169
An 11-year-old boy has complained of pain in the region of the right upper thigh for 2 weeks. This pain is worse at night and is relieved by aspirin. On physical examination no abnormal findings are noted. A radiograph of his right leg reveals a small lucent area in the proximal femoral cortex surrounded by sclerotic bone. Which of the following is the most likely diagnosis?
A Enchondroma
B Multiple myeloma
C Eosinophilic granuloma
D Osteoid osteoma
E Osteochondroma
F Ewing sarcoma
-------------------------------------------
(D) CORRECT. There is a central nidus with surrounding sclerotic bone. They are very painful from release of prostaglandins.
(A) Incorrect. Though an enchondroma occurs within bone, there is not a radiolucent nidus.
(B) Incorrect. This is a lesion filled with plasma cells and seen in older adults.
(C) Incorrect. This lesion has a variety of inflammatory cells, including eosinophils and usually does not have surrounding sclerotic bone.
(E) Incorrect. This lesion usually produces a lateral projection from the bony cortex.
(F) Incorrect. A Ewing sarcoma is unlikely to be so localized as this, and pain from a malignancy is unlikely to be relieved by aspirin.
------------------------------------
Question 170
A 69-year-old man has experienced a 5 kg weight loss in the past two months without dieting. He is a non-smoker. During the past 3 weeks he has had extensive bone pain in his back and extremities. On physical examination the range of motion of his extremities is normal. His stool is negative for occult blood. A radiograph of the spine shows focal vertebral masses with increased brightness. A nuclear medicine scan reveals focal areas of increased uptake ("hot spots") in the pelvis, vertebrae, and ribs. Laboratory studies show a serum alkaline phosphatase of 281 U/L. A urinalysis is normal. Which of the following neoplasms is he most likely to have?
A Adenocarcinoma of colon
B Oat cell carcinoma of lung
C Infiltrating ductal carcinoma of breast
D Renal cell carcinoma
E Adenocarcinoma of prostate
----------------------------------------------
(E) CORRECT. Prostate adenocarcinomas often produce osteoblastic metastases. They are one of the most common malignancies in older men.
(A) Incorrect. Colonic adenocarcinomas metastasize to bone infrequently. Many colon cancers bleed to produce a positive stool occult blood test.
(B) Incorrect. Oat cell (small cell anaplastic) carcinomas of lung often metastasize widely, particularly to bone, but are almost exclusive to smokers.
(C) Incorrect. Breast cancers are known for their propensity to bone metastasis. Breast cancers are rare in men.
(D) Incorrect. Renal cell carcinomas can produce osteolytic metastases. In the absence of hematuria, a large renal cell carcinoma capable of metastases is unlikely.
A clinical study is performed with subjects who have been diagnosed with a primary bone lesion. The demographic data for these subjects is analyzed. Which of the following bone diseases is most likely to be found to have a female predominance?
A Aneurysmal bone cyst
B Osteosarcoma
C Chondrosarcoma
D Ewing sarcoma
E Osteochondroma
---------------------------------------
(A) CORRECT. Most bone lesions (and the worst ones) have a male predominance.
(B) Incorrect. Primary malignant tumors of bone have a male predominance.
(C) Incorrect. Primary malignant tumors of bone have a male predominance.
(D) Incorrect. Primary malignant tumors of bone have a male predominance.
(E) Incorrect. Primary malignant tumors of bone have a male predominance.
----------------------------------------
Question 162
A 21-year-old college student has noted increasing pain and soreness in his left shoulder after a summer working on the ranch and bucking bales of hay (heavy lifting and turning motions) while at a ranch up in the Cache Valley. On physical examination he can hardly adduct his left arm to the level of his shoulder. An aspiration of the subacromial region is performed and clear fluid is obtained. Which of the following is the most likely diagnosis?
A Tenosynovitis
B Costochondritis
C Bursitis
D Ganglion cyst
E Pseudogout
-------------------------------------------
(C) CORRECT. Synovial-lined bursal sacs become inflamed and distended with watery fluid, more often in males engaging in excessive manual labor or exercise.
(A) Incorrect. Inflammation of the tendon sheath is more common in the wrists and hands.
(B) Incorrect. Costochondral junctions of ribs are present in the anterior chest.
(D) Incorrect. These cysts in the connective tissue of a tendon sheath or joint capsule are usually seen in the wrist.
(E) Incorrect. Deposition of calcium pyrophosphate crystals in pseudogout is more typical of persons over age 50 and usually involves the knee.
-------------------------------------------
Question 163
Over the past 4 days, an 18-year-old man has developed marked pain and swelling in his right hip that makes movement difficult. He has no history of major medical problems. On physical examination there is pain on movement with diminished range of motion of the hip. A joint aspirate from the hip reveals cloudy fluid that on microscopic examination shows numerous neutrophils but no crystals. Which of the following conditions is most likely to have preceded development of his hip problem?
A Gonococcal urethritis
B Sickle cell anemia
C Rheumatoid arthritis
D Systemic lupus erythematosus
E Erythema chronicum migrans
---------------------------------------------------------
(A) CORRECT. Neisseria gonorrheae infection can produce an acute arthritis. A gram stain of a joint aspirate may show many neutrophils with intracellular gram-negative diplococci.
(B) Incorrect. Sickle cell anemia may be associated with osteomyelitis due to Salmonella organisms, but this is rare.
(C) Incorrect. Small joints (such as the hand) are more likely to be involved than large joints (such as the hip) with rheumatoid arthritis. There is proliferative synovitis with lymphocytes and plasma cells.
(D) Incorrect. Autoimmune diseases such as systemic lupus erythematosus are often associated with arthralgias, but there is minimal actual joint inflammation and typically no deformity.
(E) Incorrect. The arthritis of Lyme disease is often seen in stages II or III and is not typically purulent.
---------------------------------------------------
Question 164
A social worker refers a 2-year-old child to the physician because of suspected child abuse. On physical examination, the child has blue sclerae, diminished hearing in both ears, and misshapen teeth. There are no external contusions or lacerations of the skin. Radiographs of the child's extremities show recent and healing long bone fractures. Which of the following is the most likely diagnosis?
A Extensive trauma ("shaken child syndrome")
B Osteogenesis imperfecta
C Achondroplasia
D Rickets
E Osteopetrosis
----------------------------------------------------
(B) CORRECT. This is a disorder of type 1 collagen synthesis, with subsequent risk for fractures of bone. The blue sclerae, hearing loss, and dental abnormalities are characteristic for OI.
(A) Incorrect. Don't make the mistake of assuming all fractures are due to trauma.
(C) Incorrect. Achondroplasia is a form of dwarfism, but it is not characterized by fractures.
(D) Incorrect. The bones in a growing child with rickets will be deformed, but extensive fractures are not common.
(E) Incorrect. This rare condition (Albers-Schonberg disease) is a hereditary defect in osteoclast function with markedly thickened, sclerotic bone that fractures readily.
-------------------------------------------------------------------
Question 165
A 23-year-old G2 P1 woman has noted minimal fetal movement at 18 weeks gestation. An ultrasound scan shows that the fetal limbs are shortened. At 30 weeks gestation a stillborn fetus is delivered. A postmortem radiograph reveals extensive long bone, rib, and pelvic fractures. Autopsy reveals a normal appearance to internal organs. A mutation involving a gene encoding for which of the following proteins is most likely to produce these findings?
A Fibrillin
B Fibroblast growth factor receptor 3
C Retinoblastoma
D Neurofibromin
E Type I collagen
-----------------------------------------------------
(E) CORRECT. Osteogenesis imperfecta is an inherited disorder (usually autosomal recessive) of type I collagen synthesis. This is OI type II, the perinatal lethal form..
(A) Incorrect. Mutations of the fibrillin gene are present with Marfan syndrome, which affects the connective tissue of the cardiovascular system most severely.
(B) Incorrect. The FGFR gene mutations are associated with skeletal dysplasias, such as achondroplasia, that are not usually accompanied by fractures.
(C) Incorrect. The Rb gene is a tumor suppressor gene. If both copies of the gene are mutated, then the risk for malignancy is increased. One of the malignancies that can occur is osteosarcoma.
(D) Incorrect. NF1 can be associated with bone deformities beginning in childhood as a consequence of growth of neurofibromas.
----------------------------------------------------------
Question 166
A 41-year-old previously healthy man has had backache with muscle spasms, weakness, and pain felt in the right hip radiating all the way to his toes for the past 8 months. He does not have headaches or other neurologic problems. Physical examination reveals that the circumference of his right leg is smaller than the left, and he has paresthesias in an L5 distribution in the right leg. Which of the following conditions is he most likely to have?
A Spondylolisthesis
B Spina bifida
C Herniated nucleus pulposus
D Osteoporosis
E Paget disease of bone
--------------------
(C) CORRECT. He has a herniated intervertebral disk in which impingement on spinal nerve roots (usually L5 or S1) produces sensory and motor disturbances.
(A) Incorrect. In this disorder, the vertebral body, pedicles, and facets 'slips' forward to produce back pain, and limited motion. Symptoms are often bilateral.
(B) Incorrect. This is a failure of fusion of the laminae of the neural arch and is usually occult until an injury or radiograph reveals it.
(D) Incorrect. Osteoporosis at his age and in a male is unlikely. Compressed vertebral fractures may involve nerve roots, but are not as likely as a herniated disk.
(E) Incorrect. This is unlikely at his age. Paget is often painless, but if advanced, a nerve root may become entrapped.
-----------------------------
Question 167
A 5-year-old child has complained of pain on the left side of his head for 3 weeks. There are no abnormal findings on physical examination. A skull radiograph reveals a solitary destructive bony lesion of the left mastoid region. A biopsy is performed and microscopic examination shows that this lesion is composed histologically of a mixed inflammatory cell infiltrate. Which of the following is the most likely diagnosis?
A Osteoid osteoma
B Letterer-Siwe syndrome
C Eosinophilic granuloma
D Osteitis fibrosa cystica
E Tuberculosis
-----------------------------------
(C) CORRECT. Eosinophilic granulomas are a localized form of Langerhans cell histiocytosis that can be found in skull or long bones and can mimic osteomyelitis. The mixed inflammatory cell infiltrated can have histiocytes, eosinophils, plasma cells, and lymphocytes.
(A) Incorrect. This lesion has a central nidus surrounded by sclerotic bone.
(B) Incorrect. This disseminated form of Langerhans cell histiocytosis most often occurs in children under 3.
(D) Incorrect. This localized bone lesion occurs most often in patients with hyperparathyroidism.
(E) Incorrect. Epithelioid macrophages and Langhans giant cells should be present in a granuloma with M. tuberculosis.
--------------------------------------
Question 168
A 49-year-old man has complained of episodes of joint pain for over 10 years. This pain has occurred in a remitting and relapsing pattern. On physical examination there are deformities of his hands involving the fingers, with swan-neck deformities and ulnar deviation. His condition improves following corticosteroid and gold therapy. Which of the following serologic tests is most likely to be positive in this man?
A Rapid plasma reagin
B HLA-B27
C Anti-double stranded DNA
D Rheumatoid factor
E Borrelia burgdorferi
------------------------
(D) CORRECT. Joint deformity frequently occurs with chronic rheumatoid arthritis. Females are affected more than males, and pregnancy may lessen the severity of the disease. However, men can get RA.
(A) Incorrect. The RPR is a screening test for syphilis. Gummatous necrosis in tertiary syphilis may involve large joints such as the knees..
(B) Incorrect. HLA-B27 is often positive in ankylosing spondylitis which involves the spine.
(C) Incorrect. The anti-double stranded DNA positivity is most specific for systemic lupus erythematosus, which is unlikely to be complicated by joint deformity.
(E) Incorrect. Ankylosis can and does occur often with severe rheumatoid arthritis.
--------------------------------
Question 169
An 11-year-old boy has complained of pain in the region of the right upper thigh for 2 weeks. This pain is worse at night and is relieved by aspirin. On physical examination no abnormal findings are noted. A radiograph of his right leg reveals a small lucent area in the proximal femoral cortex surrounded by sclerotic bone. Which of the following is the most likely diagnosis?
A Enchondroma
B Multiple myeloma
C Eosinophilic granuloma
D Osteoid osteoma
E Osteochondroma
F Ewing sarcoma
-------------------------------------------
(D) CORRECT. There is a central nidus with surrounding sclerotic bone. They are very painful from release of prostaglandins.
(A) Incorrect. Though an enchondroma occurs within bone, there is not a radiolucent nidus.
(B) Incorrect. This is a lesion filled with plasma cells and seen in older adults.
(C) Incorrect. This lesion has a variety of inflammatory cells, including eosinophils and usually does not have surrounding sclerotic bone.
(E) Incorrect. This lesion usually produces a lateral projection from the bony cortex.
(F) Incorrect. A Ewing sarcoma is unlikely to be so localized as this, and pain from a malignancy is unlikely to be relieved by aspirin.
------------------------------------
Question 170
A 69-year-old man has experienced a 5 kg weight loss in the past two months without dieting. He is a non-smoker. During the past 3 weeks he has had extensive bone pain in his back and extremities. On physical examination the range of motion of his extremities is normal. His stool is negative for occult blood. A radiograph of the spine shows focal vertebral masses with increased brightness. A nuclear medicine scan reveals focal areas of increased uptake ("hot spots") in the pelvis, vertebrae, and ribs. Laboratory studies show a serum alkaline phosphatase of 281 U/L. A urinalysis is normal. Which of the following neoplasms is he most likely to have?
A Adenocarcinoma of colon
B Oat cell carcinoma of lung
C Infiltrating ductal carcinoma of breast
D Renal cell carcinoma
E Adenocarcinoma of prostate
----------------------------------------------
(E) CORRECT. Prostate adenocarcinomas often produce osteoblastic metastases. They are one of the most common malignancies in older men.
(A) Incorrect. Colonic adenocarcinomas metastasize to bone infrequently. Many colon cancers bleed to produce a positive stool occult blood test.
(B) Incorrect. Oat cell (small cell anaplastic) carcinomas of lung often metastasize widely, particularly to bone, but are almost exclusive to smokers.
(C) Incorrect. Breast cancers are known for their propensity to bone metastasis. Breast cancers are rare in men.
(D) Incorrect. Renal cell carcinomas can produce osteolytic metastases. In the absence of hematuria, a large renal cell carcinoma capable of metastases is unlikely.
60 - orthopedics mcqs - 151 to 160 - bone pathology
Question 151
A 16-year-old boy has noted pain in his left knee after each hockey practice session for the past month. On examination there is tenderness to palpation of his left knee, with reduced range of motion. A plain film radiograph of the left leg reveals a mass of the proximal tibial metaphysis that erodes the bone cortex, lifting up the periosteum where reactive new bone is apparent. The mass does not extend into the epiphyseal region. A bone biopsy is performed and microscopic examination shows atypical, elongated cells with hyperchromatic nuclei in an osteoid stroma. Which of the following neoplasms is he most likely to have?
A Ewing sarcoma
B Osteosarcoma
C Chondrosarcoma
D Multiple myeloma
E Metastatic seminoma
----------------------------------------------
(B) CORRECT. Osteoid production is characteristic for osteosarcoma. The location about the knee is common. Most arise in the metaphyseal region. Overall, malignancies are uncommon in children, but bone tumors are one of the most common malignancies at this age.
(A) Incorrect. Ewing sarcoma has a peak incidence at a younger age. It most often involves the diaphyseal region. It does not produce osteoid.
(C) Incorrect. Chondrosarcomas do not make osteoid. They can occur overa wide age range.
(D) Incorrect. Myelomas are seen in older adults and produce lytic bone lesions filled with plasma cells.
(E) Incorrect. Metastases are unlikely to occur at this age. Overall, metastases are the most common malignancy involving bone. Primary bone tumors are not common.
-----------------------------------------------
Question 152
A 53-year-old man has noted a slowly enlarging "bump" on his left elbow for the past 2 years. On physical examination there is a 2 cm firm, non-tender mass over the left olecranon process. The mass is excised and on sectioning has a chalky white consistency. Microscopically, the mass is composed of elongated, needle-shaped crystals that under polarized light are negatively birefringent. Surrounding the crystals is a granulomatous inflammatory infiltrate. Which of the following laboratory test findings is he most likely to have?
A Hyperuricemia
B Hyperglycemia
C Elevated rheumatoid factor
D Hypercholesterolemia
E Increased serum creatinine
F Hypercalcemia
----------------------------------------------
(A) CORRECT. Gouty tophi can develop with gout. He has increased deposition of sodium urate crystals in the soft tissue around a joint. Most patients with an increased serum uric acid do not have a gouty arthritis, though some do.
(B) Incorrect. Gout is unrelated to diabetes mellitus.
(C) Incorrect. Persons with rheumatoid arthritis may have rheumatoid nodules in a similar location, and they are a form of granuloma, but there is no deposition of sodium urate crystals with rheumatoid arthritis.
(D) Incorrect. Gouty tophi are not related to cholesterol metabolism.
(E) Incorrect. An increased serum creatinine may occur with renal failure, and gout may cause renal failure, but the presence of gouty tophi is more likely related to deranged uric acid metabolism.
(F) Incorrect. An increased serum calcium could rarely lead to metastatic calcification, which may occur in lung, stomach, and kidney, but not as large deposits.
-----------------------------------
Question 153
A 5-year-old boy measures than the 5th percentile in height for age. On physical examination most of his decreased height is due to very short legs. However, his trunk and head appear normally proportioned for age. He is of above average intelligence and becomes an orthopedic surgeon. His parents and relatives are not affected by this disorder. Which of the following is the most likely diagnosis?
A Fibrous dysplasia
B Osteogenesis imperfecta
C Ollier disease
D Alport syndrome
E Achondroplasia
F Thanatophoric dysplasia
----------------------------------------
(E) CORRECT. This is the most common form of short-limbed dwarfism. Though it has an autosomal dominant inheritance pattern, about half of cases represent new mutations, and there is no family history. Heterozygotes have normal longevity, while homozygotes usually die soon after birth.
(A) Incorrect. Fibrous dysplasia can be seen with McCune-Albright syndrome.
(B) Incorrect. Osteogenesis imperfecta leads to multiple fractures. There are several forms.
(C) Incorrect. Ollier disease is associated with enchondromatosis.
(D) Incorrect. Alport syndrome is associated with renal failure and deafness.
(F) Incorrect. Thanatophoric dysplasia is a form of short-limbed dwarfism that is lethal in utero or shortly after birth.
----------------------------------------
Question 154
A 38-year-old woman has severe systemic lupus erythematosus with renal complications. She is treated with long-term corticosteroid therapy. Which of the following bone diseases is she most likely to develop?
A Paget disease of bone
B Rickets
C Osteochondritis
D Osteoporosis
E Osteomalacia
---------------------------------------
(D) CORRECT. Osteoporosis is one of the complications of long-term therapy with corticosteroids.
(A) Incorrect. Paget disease of bone is not related to corticosteroid therapy.
(B) Incorrect. Rickets is due to a deficiency of vitamin D in children with growing bones.
(C) Incorrect. Osteochondritis is an inflammatory process. Corticosteroids reduce inflammation.
(E) Incorrect. This is due to vitamin D deficiency in adults.
-------------------------------------------
Question 155
A 15-year-old girl is noted to have an odd, twisted appearance to her back while she is out swimming with her friends. She is tall and thin. A radiograph reveals an abnormal lateral bowing of the spine, with 20 degrees of lateral curvature in the mid-thoracic region. Which of the following is most likely to produce these findings?
A Asymmetric cartilage growth of vertebral body end plates
B Multiple osteochondromas of the vertebral bodies
C Vitamin D deficiency with rickets
D A disorder of procollagen synthesis with multiple compressed fractures
E Trauma
-----------------------------------------------
(A) CORRECT. She has scoliosis, which is an idiopathic, but not uncommon, condition that has a female predominance.
(B) Incorrect. Osteochondromatosis is rare and is seen mostly in males. The extremities are affected most, and dwarfism results in severe cases.
(C) Incorrect. The bony deformities of rickets would not likely be asymmetric.
(D) Incorrect. She does not have osteogenesis imperfecta, which is associated with multiple fractures, particularly of long bones.
(E) Incorrect. Trauma may lead to bone deformities, but not typically of the spine with lateral curvature.
--------------------------------------------------
Question 156
A 23-year-old man notes some minor discomfort over the lateral aspect of his right knee after a day working in a cramped cubicle (because IT put the 'desktop' workstation on the floor). On physical examination he has a palpable "bump" in this region. A radiograph of the knee reveals a lateral bony projection from the lower femoral metaphysis. There is no adjacent soft tissue swelling. The lesion is excised and is composed of a 3 cm stalk of bony cortex capped by cartilage. Which of the following is the most likely diagnosis?
A Osteochondroma
B Giant cell tumor
C Aneurysmal bone cyst
D Osteoid osteoma
E Enchondroma
------------------------------------------------
(A) CORRECT. Osteochcondromas are not true neoplasms but an exaggeration of the growth plate. They are benign and slow-growing. They may cause discomfort because they project outward from the bone.
(B) Incorrect. These tumors expand the bone outward.
(C) Incorrect. These are located in the metaphysis and are expansile lesions.
(D) Incorrect. These are located within the bone. A small nidus is surrounded by sclerotic bone.
(E) Incorrect. These are located within bone.
----------------------------------------------
Question 157
A 75-year-old man has complained of lower back pain for 8 years. As part of a workup for a persistently elevated lymphocytosis, he has a right posterior iliac crest marrow biopsy performed. On microscopic examination hematopoiesis is normal, but the bone spicules are thickened with irregular cement lines forming a mosaic appearance with both increased osteoblastic and osteoclastic activity. Which of the following conditions is most likely to occur in conjunction with his underlying disease process?
A Dementia
B Myelofibrosis
C Hepatic cirrhosis
D Chronic renal failure
E Congestive heart failure
--------------------------------------------------
(E) CORRECT. He has Paget disease of bone, and he has the classic phase of mixed osteolysis and osteogenesis. The increased blood flow into the involved areas of bone can lead to high output congestive heart failure in older persons with minimal cardiac reserve. Paget disease of bone is most often seen in older Caucasians.
(A) Incorrect. Bone diseases are not associated with dementias.
(B) Incorrect. The involvement of Paget disease of bone, even if polyostotic, is not extensive enough to affect hematopoiesis.
(C) Incorrect. Paget disease of bone does not affect the liver.
(D) Incorrect. The biochemical abnormalities of Paget disease of bone are subtle and not likely to affect renal function.
---------------------------------------------------
Question 158
Bone densitometry performed on a 42-year-old woman shows her bone mass decreased more than 2 standard deviations below the mean for age in her left femoral head, wrist, and lumbar vertebral region. Six months later, the amount of bone loss is seen to be increased by repeat densitometry examination. These findings are most likely to be associated with which of the following serum laboratory test abnormalities:
A Parathormone of 5 pg/mL
B Cortisol of 75 microgm/dL
C Total immunoglobulin of 3.5 g/dL
D Uric acid of 15.7 mg/dL
E Total cholesterol of 514 mg/dL
F Alkaline phosphatase of 238 U/L
----------------------------------------------------------
(B) CORRECT. She has osteoporosis with decreased bone mass. Most cases do not have a specific etiology, but Cushing syndrome with hypercortisolism can promote osteoporosis. Her age should make you suspicious, since she is not likely to be postmenopausal.
(A) Incorrect. Hypoparathyroidism is not going to accelerate bone loss. The bone resorption that accompanies hyperparathyroidism can cause osteoporosis. Over 95% of cases of osteoporosis are 'primary' with unknown cause.
(C) Incorrect. This elevation in serum globulin should make you suspect a monoclonal gammopathy, but myeloma leads to focal bone lytic lesions.
(D) Incorrect. Hyperuricemia can be associated with gout that can cause focal bone destrution near affected joints, the bone mass overall is not decreased.
(E) Incorrect. Hypercholesterolemia is associated with accelerated atherosclerosis which does not affect bone mass.
(F) Incorrect. She is not likely to have an increased alkaline phosphatase, even though her bone loss is accelerated.
-----------------------------------------------------------
Question 159
A 30-year-old healthy man has experienced headaches for the past month. On physical examination there are no abnormal findings. Laboratory studies show a serum calcium of 12.2 mg/dL with phosphorus of 2.5 mg/dL and albumin of 4.3 g/dL. Which of the following bone lesions is most frequently associated with these findings?
A Osteochondroma
B Giant cell tumor
C Paget disease of bone
D Osteitis fibrosa cystica
E Fibrous dysplasia
----------------------------------------------------------
(D) CORRECT. This lesion is filled with osteoclasts and can have a cystic appearance on radiography. In some cases the osteoclast proliferation is so florid that a 'brown tumor' is formed. There is an association with hyperparathyroidism. Persons with hyperparathyroidism may feel well, but may also have headaches, bone pain, or abdominal pain.
(A) Incorrect. This lateral projection from the cortex is not associated with disorders of calcium metabolism.
(B) Incorrect. The appearance of this neoplasm is not related to hyperparathyroidism.
(C) Incorrect. Paget disease of bone is not related to calcium metabolism or parathyroid function.
(E) Incorrect. Fibrous dysplasia does not result from hyperparathyroidism.
--------------------------------------------------------
Question 160
During the past year a 22-year-old man begins to note persistent lower back pain and stiffness that diminishes with activity. Within the next 10 years he develops hip and shoulder pain with decreased range of motion. On physical examination at age 42 he has diminished lumbar lordosis with decreased lumbar spine mobility. He has no other major medical problems. Which of the following is the most likely diagnosis?
A Rheumatoid arthritis
B Ankylosing spondylitis
C Osteoarthritis
D Lyme disease
E Calcium pyrophosphate dihydrate deposition disease
---------------------------------------------------
(B) CORRECT. He probably is also HLA B27 positive. The earlier in life the disease begins, the worse the prognosis. There is a progressive bony ankylosis, especially of sacroiliac joints and spine.
(A) Incorrect. RA typically involves small joints.
(C) Incorrect. Osteoarthritis typically involves a single large joint.
(D) Incorrect. However, the third stage of Lyme disease can have intermittent attacks of arthritis involving large joints, particularly knee, with swelling.
(E) Incorrect. 'Pseudogout' is more typical of the elderly and occurs in acute attacks.
A 16-year-old boy has noted pain in his left knee after each hockey practice session for the past month. On examination there is tenderness to palpation of his left knee, with reduced range of motion. A plain film radiograph of the left leg reveals a mass of the proximal tibial metaphysis that erodes the bone cortex, lifting up the periosteum where reactive new bone is apparent. The mass does not extend into the epiphyseal region. A bone biopsy is performed and microscopic examination shows atypical, elongated cells with hyperchromatic nuclei in an osteoid stroma. Which of the following neoplasms is he most likely to have?
A Ewing sarcoma
B Osteosarcoma
C Chondrosarcoma
D Multiple myeloma
E Metastatic seminoma
----------------------------------------------
(B) CORRECT. Osteoid production is characteristic for osteosarcoma. The location about the knee is common. Most arise in the metaphyseal region. Overall, malignancies are uncommon in children, but bone tumors are one of the most common malignancies at this age.
(A) Incorrect. Ewing sarcoma has a peak incidence at a younger age. It most often involves the diaphyseal region. It does not produce osteoid.
(C) Incorrect. Chondrosarcomas do not make osteoid. They can occur overa wide age range.
(D) Incorrect. Myelomas are seen in older adults and produce lytic bone lesions filled with plasma cells.
(E) Incorrect. Metastases are unlikely to occur at this age. Overall, metastases are the most common malignancy involving bone. Primary bone tumors are not common.
-----------------------------------------------
Question 152
A 53-year-old man has noted a slowly enlarging "bump" on his left elbow for the past 2 years. On physical examination there is a 2 cm firm, non-tender mass over the left olecranon process. The mass is excised and on sectioning has a chalky white consistency. Microscopically, the mass is composed of elongated, needle-shaped crystals that under polarized light are negatively birefringent. Surrounding the crystals is a granulomatous inflammatory infiltrate. Which of the following laboratory test findings is he most likely to have?
A Hyperuricemia
B Hyperglycemia
C Elevated rheumatoid factor
D Hypercholesterolemia
E Increased serum creatinine
F Hypercalcemia
----------------------------------------------
(A) CORRECT. Gouty tophi can develop with gout. He has increased deposition of sodium urate crystals in the soft tissue around a joint. Most patients with an increased serum uric acid do not have a gouty arthritis, though some do.
(B) Incorrect. Gout is unrelated to diabetes mellitus.
(C) Incorrect. Persons with rheumatoid arthritis may have rheumatoid nodules in a similar location, and they are a form of granuloma, but there is no deposition of sodium urate crystals with rheumatoid arthritis.
(D) Incorrect. Gouty tophi are not related to cholesterol metabolism.
(E) Incorrect. An increased serum creatinine may occur with renal failure, and gout may cause renal failure, but the presence of gouty tophi is more likely related to deranged uric acid metabolism.
(F) Incorrect. An increased serum calcium could rarely lead to metastatic calcification, which may occur in lung, stomach, and kidney, but not as large deposits.
-----------------------------------
Question 153
A 5-year-old boy measures than the 5th percentile in height for age. On physical examination most of his decreased height is due to very short legs. However, his trunk and head appear normally proportioned for age. He is of above average intelligence and becomes an orthopedic surgeon. His parents and relatives are not affected by this disorder. Which of the following is the most likely diagnosis?
A Fibrous dysplasia
B Osteogenesis imperfecta
C Ollier disease
D Alport syndrome
E Achondroplasia
F Thanatophoric dysplasia
----------------------------------------
(E) CORRECT. This is the most common form of short-limbed dwarfism. Though it has an autosomal dominant inheritance pattern, about half of cases represent new mutations, and there is no family history. Heterozygotes have normal longevity, while homozygotes usually die soon after birth.
(A) Incorrect. Fibrous dysplasia can be seen with McCune-Albright syndrome.
(B) Incorrect. Osteogenesis imperfecta leads to multiple fractures. There are several forms.
(C) Incorrect. Ollier disease is associated with enchondromatosis.
(D) Incorrect. Alport syndrome is associated with renal failure and deafness.
(F) Incorrect. Thanatophoric dysplasia is a form of short-limbed dwarfism that is lethal in utero or shortly after birth.
----------------------------------------
Question 154
A 38-year-old woman has severe systemic lupus erythematosus with renal complications. She is treated with long-term corticosteroid therapy. Which of the following bone diseases is she most likely to develop?
A Paget disease of bone
B Rickets
C Osteochondritis
D Osteoporosis
E Osteomalacia
---------------------------------------
(D) CORRECT. Osteoporosis is one of the complications of long-term therapy with corticosteroids.
(A) Incorrect. Paget disease of bone is not related to corticosteroid therapy.
(B) Incorrect. Rickets is due to a deficiency of vitamin D in children with growing bones.
(C) Incorrect. Osteochondritis is an inflammatory process. Corticosteroids reduce inflammation.
(E) Incorrect. This is due to vitamin D deficiency in adults.
-------------------------------------------
Question 155
A 15-year-old girl is noted to have an odd, twisted appearance to her back while she is out swimming with her friends. She is tall and thin. A radiograph reveals an abnormal lateral bowing of the spine, with 20 degrees of lateral curvature in the mid-thoracic region. Which of the following is most likely to produce these findings?
A Asymmetric cartilage growth of vertebral body end plates
B Multiple osteochondromas of the vertebral bodies
C Vitamin D deficiency with rickets
D A disorder of procollagen synthesis with multiple compressed fractures
E Trauma
-----------------------------------------------
(A) CORRECT. She has scoliosis, which is an idiopathic, but not uncommon, condition that has a female predominance.
(B) Incorrect. Osteochondromatosis is rare and is seen mostly in males. The extremities are affected most, and dwarfism results in severe cases.
(C) Incorrect. The bony deformities of rickets would not likely be asymmetric.
(D) Incorrect. She does not have osteogenesis imperfecta, which is associated with multiple fractures, particularly of long bones.
(E) Incorrect. Trauma may lead to bone deformities, but not typically of the spine with lateral curvature.
--------------------------------------------------
Question 156
A 23-year-old man notes some minor discomfort over the lateral aspect of his right knee after a day working in a cramped cubicle (because IT put the 'desktop' workstation on the floor). On physical examination he has a palpable "bump" in this region. A radiograph of the knee reveals a lateral bony projection from the lower femoral metaphysis. There is no adjacent soft tissue swelling. The lesion is excised and is composed of a 3 cm stalk of bony cortex capped by cartilage. Which of the following is the most likely diagnosis?
A Osteochondroma
B Giant cell tumor
C Aneurysmal bone cyst
D Osteoid osteoma
E Enchondroma
------------------------------------------------
(A) CORRECT. Osteochcondromas are not true neoplasms but an exaggeration of the growth plate. They are benign and slow-growing. They may cause discomfort because they project outward from the bone.
(B) Incorrect. These tumors expand the bone outward.
(C) Incorrect. These are located in the metaphysis and are expansile lesions.
(D) Incorrect. These are located within the bone. A small nidus is surrounded by sclerotic bone.
(E) Incorrect. These are located within bone.
----------------------------------------------
Question 157
A 75-year-old man has complained of lower back pain for 8 years. As part of a workup for a persistently elevated lymphocytosis, he has a right posterior iliac crest marrow biopsy performed. On microscopic examination hematopoiesis is normal, but the bone spicules are thickened with irregular cement lines forming a mosaic appearance with both increased osteoblastic and osteoclastic activity. Which of the following conditions is most likely to occur in conjunction with his underlying disease process?
A Dementia
B Myelofibrosis
C Hepatic cirrhosis
D Chronic renal failure
E Congestive heart failure
--------------------------------------------------
(E) CORRECT. He has Paget disease of bone, and he has the classic phase of mixed osteolysis and osteogenesis. The increased blood flow into the involved areas of bone can lead to high output congestive heart failure in older persons with minimal cardiac reserve. Paget disease of bone is most often seen in older Caucasians.
(A) Incorrect. Bone diseases are not associated with dementias.
(B) Incorrect. The involvement of Paget disease of bone, even if polyostotic, is not extensive enough to affect hematopoiesis.
(C) Incorrect. Paget disease of bone does not affect the liver.
(D) Incorrect. The biochemical abnormalities of Paget disease of bone are subtle and not likely to affect renal function.
---------------------------------------------------
Question 158
Bone densitometry performed on a 42-year-old woman shows her bone mass decreased more than 2 standard deviations below the mean for age in her left femoral head, wrist, and lumbar vertebral region. Six months later, the amount of bone loss is seen to be increased by repeat densitometry examination. These findings are most likely to be associated with which of the following serum laboratory test abnormalities:
A Parathormone of 5 pg/mL
B Cortisol of 75 microgm/dL
C Total immunoglobulin of 3.5 g/dL
D Uric acid of 15.7 mg/dL
E Total cholesterol of 514 mg/dL
F Alkaline phosphatase of 238 U/L
----------------------------------------------------------
(B) CORRECT. She has osteoporosis with decreased bone mass. Most cases do not have a specific etiology, but Cushing syndrome with hypercortisolism can promote osteoporosis. Her age should make you suspicious, since she is not likely to be postmenopausal.
(A) Incorrect. Hypoparathyroidism is not going to accelerate bone loss. The bone resorption that accompanies hyperparathyroidism can cause osteoporosis. Over 95% of cases of osteoporosis are 'primary' with unknown cause.
(C) Incorrect. This elevation in serum globulin should make you suspect a monoclonal gammopathy, but myeloma leads to focal bone lytic lesions.
(D) Incorrect. Hyperuricemia can be associated with gout that can cause focal bone destrution near affected joints, the bone mass overall is not decreased.
(E) Incorrect. Hypercholesterolemia is associated with accelerated atherosclerosis which does not affect bone mass.
(F) Incorrect. She is not likely to have an increased alkaline phosphatase, even though her bone loss is accelerated.
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Question 159
A 30-year-old healthy man has experienced headaches for the past month. On physical examination there are no abnormal findings. Laboratory studies show a serum calcium of 12.2 mg/dL with phosphorus of 2.5 mg/dL and albumin of 4.3 g/dL. Which of the following bone lesions is most frequently associated with these findings?
A Osteochondroma
B Giant cell tumor
C Paget disease of bone
D Osteitis fibrosa cystica
E Fibrous dysplasia
----------------------------------------------------------
(D) CORRECT. This lesion is filled with osteoclasts and can have a cystic appearance on radiography. In some cases the osteoclast proliferation is so florid that a 'brown tumor' is formed. There is an association with hyperparathyroidism. Persons with hyperparathyroidism may feel well, but may also have headaches, bone pain, or abdominal pain.
(A) Incorrect. This lateral projection from the cortex is not associated with disorders of calcium metabolism.
(B) Incorrect. The appearance of this neoplasm is not related to hyperparathyroidism.
(C) Incorrect. Paget disease of bone is not related to calcium metabolism or parathyroid function.
(E) Incorrect. Fibrous dysplasia does not result from hyperparathyroidism.
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Question 160
During the past year a 22-year-old man begins to note persistent lower back pain and stiffness that diminishes with activity. Within the next 10 years he develops hip and shoulder pain with decreased range of motion. On physical examination at age 42 he has diminished lumbar lordosis with decreased lumbar spine mobility. He has no other major medical problems. Which of the following is the most likely diagnosis?
A Rheumatoid arthritis
B Ankylosing spondylitis
C Osteoarthritis
D Lyme disease
E Calcium pyrophosphate dihydrate deposition disease
---------------------------------------------------
(B) CORRECT. He probably is also HLA B27 positive. The earlier in life the disease begins, the worse the prognosis. There is a progressive bony ankylosis, especially of sacroiliac joints and spine.
(A) Incorrect. RA typically involves small joints.
(C) Incorrect. Osteoarthritis typically involves a single large joint.
(D) Incorrect. However, the third stage of Lyme disease can have intermittent attacks of arthritis involving large joints, particularly knee, with swelling.
(E) Incorrect. 'Pseudogout' is more typical of the elderly and occurs in acute attacks.
59 - orthopedics mcqs - 141 to 150 - bone pathology
Question 141
An otherwise healthy 44-year-old man with no prior medical history has had increasing back pain and right hip pain for the past decade. The pain is worse at the end of the day. On physical examination he has bony enlargement of the distal interphalangeal joints. A radiograph of the spine reveals the presence of prominent osteophytes involving the vertebral bodies. There is sclerosis with narrowing of the joint space at the right acetabulum seen on a radiograph of the pelvis. Which of the following diseases is he most likely to have?
A Gout
B Rheumatoid arthritis
C Osteoarthritis
D Osteomyelitis
E Lyme disease
F Pseudogout
-----------------------------------
(C) CORRECT. Degenerative osteoarthritis is a common and progressive condition that becomes more frequent and symptomatic with aging. There is erosion and loss of articular cartilage with joint space narrowing. There is minimal inflammation.
(A) Incorrect. A gouty arthritis is more likely to be accompanied by swelling, and deformity with joint destruction. The pain is not related to usage.
(B) Incorrect. Rheumatoid arthritis typically involves small joints of the hands and feet most severely, and there is a destructive pannus that leads to marked joint deformity.
(D) Incorrect. Osteomyelitis represents an ongoing infection that produces marked bone deformity, not just joint narrowing.
(E) Incorrect. Lyme disease produces a chronic arthritis, but it is typically preceded by a deer tick bite with a skin lesion. It is much less common than osteoarthritis.
(F) Incorrect. Pseudogout, or calcium pyrophosphate dihydrate deposition disease, is more often a disease of the elderly, accompanied by meniscal calcification and joint space narrowing. There can be acute attacks with marked pain. The knees are most often involved.
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Question 142
An 80-year-old woman has had no major medical problems, but she has never been physically active for most of her life. One day she falls out of bed and immediately notes a sharp pain in her left hip. She is subsequently unable to ambulate without severe pain. Radiographs show not only a fracture of the left femoral head, but also a compressed fracture of T10. Which of the following conditions is she most likely to have?
A Vitamin D deficiency
B Acute osteomyelitis
C Osteogenesis imperfecta
D Osteoporosis
E Polyostotic fibrous dysplasia
F Metastatic breast carcinoma
---------------------------------------------------------------------------
(D) CORRECT. She most likely has osteoporosis of bone with accelerated bone loss leading to the propensity for fractures. Physical inactivity further accelerates bone loss and decreases muscle mass and agility that contribute to falls.
(A) Incorrect. A poor diet could be lacking in vitamin D, though endogenous vitamin D production occurs with sunlight exposure. The findings are those of osteomalacia and are similar clinically to osteoporosis.
(B) Incorrect. An osteomyelitis is not typical at this age and does not usually present as fractures in multiple locations.
(C) Incorrect. This inherited disorder of collagen synthesis is initially diagnosed in fetuses and young children.
(E) Incorrect. This is a rare disorder with that can be seen with McCune-Albright syndrome.
(F) Incorrect. So-called 'pathologic fracture' from weakening of bone by metastases can occur, but such patients are often very ill, with a history of weight loss, and prior bone pain.
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Question 143
A 51-year-old man has noted right hip pain for the past 3 months. On physical examination he has diminished range of motion of the right hip. A radiograph reveals a 10 x 13 cm mass involving the right ischium of the pelvis. The mass has irregular borders and there are extensive areas of bony destruction along with some scattered calcifications. The lesion is resected, and grossly the mass has a bluish-white cut surface. Which of the following attributes is most likely to describe this mass?
A The most frequent primary tumor of bone
B Usually seen in distal skeletal bones
C More common in females
D Sometimes seen to arise in benign cartilagenous tumors
E Associated with Paget disease of bone
----------------------------------------------------------------------------------
(D) CORRECT. Though probably a sporadic occurrence in the case desccribed here, chondrosarcomas can occur in association with osteochondromatosis.
(A) Incorrect. Osteosarcoma is the most frequent primary malignancy of bone, not chondrosarcoma.
(B) Incorrect. Distal cartilagenous tumors are more likely to be benign, whereas those in a central location are virtually always malignant.
(C) Incorrect. Primary malignancies of bone, including chondrosarcoma, are more common in males.
(E) Incorrect. Some osteosarcomas are associated with Paget disease of bone, but not typically chondrosarcomas.
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Question 144
A 62-year-old man has had back pain for 4 months. No abnormal findings are noted on physical examination. A CBC shows a WBC count of 3700/microliter, hemoglobin 10.3 g/dL, hematocrit 31.1%, MCV 85 fL, and platelet count 110,000/microliter. His total serum protein is 8.5 gm/dl with an albumin of 4.1 gm/dl. A chest radiograph shows no abnormalities of heart or lung fields, but there are several lucencies noted in the vertebral bodies. A sternal bone marrow aspirate is performed and yields a dark red jelly-like material in the syringe. Which of the following cell types is most likely to be numerous on microscopic examination of this aspirate?
A Giant cells
B Fibroblasts
C Osteoblasts
D Metastatic renal carcinoma cells
E Plasma cells
-------------------------------------------------------------------
(E) CORRECT. The patient has multiple myeloma. The bone marrow needle was in a lytic lesion filled with plasma cells. His serum globulin is high as a result of his monoclonal gammopathy.
(A) Incorrect. Giant cells may be seen in a variety of benign and malignant lesions of bone, but this does not explain the hypergammaglobulinemia.
(B) Incorrect. Fibroblasts produce collagen and are more numerous with the gross appearance of firm, white scar tissue.
(C) Incorrect. Osteoblasts are most numerous in repair of bone, and callus is very firm.
(D) Incorrect. Osteolytic metastases of renal cell carcinoma could have the gross appearance described here, but would not account for hypergammaglobulinemia.
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Question 145
A 58-year-old man has the sudden onset late one evening of severe pain in his left great toe. There is no history of trauma. On examination there is edema with erythema and pain on movement of the left 1st metatarsophalangeal joint, but there is no overlying skin ulceration. A joint aspirate is performed and on microscopic examination reveals numerous neutrophils. Over the next 3 weeks, he has two more similar episodes. On physical examination between these attacks, there is minimal loss of joint mobility. Which of the following laboratory test findings is most characteristic for his underlying disease process?
A Hyperglycemia
B Positive antinuclear antibody
C Hyperuricemia
D Hypercalcemia
E High rheumatoid factor titer
-----------------------------------------------------------------
(C) CORRECT. Many patients with gout will have hyperuricemia, but not all. The big toe is the most common joint involved with gout. Acute gouty attacks are associated with intense pain from acute inflammation.
(A) Incorrect. Hyperglycemia is a feature of diabetes mellitus, which is associated with peripheral vascular disease that increases the risk for foot ulcerations and osteomyelitis.
(B) Incorrect. The arthralgias common to many autoimmune diseases with a positive ANA, such as systemic lupus erythematosus, are not usually associated with joint swelling, redness, or deformity.
(D) Incorrect. There can be bone luceny with hyperparathyroidism, but the joints are not greatly affected, nor is there swelling or redness.
(E) Incorrect. Rheumatoid arthritis leads to marked joint deformity, typically of small joints in hands and feet. The pain usually persists for weeks to months.
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Question 146
A 13-year-old boy complains of pain persisting in his left leg for 3 weeks. On physical examination his temperature is 37.9 C. A radiograph of the leg reveals a mass in the diaphyseal region of the left femur with overlying cortical erosion and soft tissue extension. A bone biopsy is performed and the lesion on microscopic examination shows numerous small round blue cells. Which of the following neoplasms is he most likely to have?
A Ewing sarcoma
B Medulloblastoma
C Neuroblastoma
D Chondroblastoma
E Osteoblastoma
------------------------------------------------------------
(A) CORRECT. A 'small round blue cell' tumor of bone is Ewing sarcoma, a form of primitive neuroectodermal tumor, commonly seen at this age and in the diaphyseal region of bone.
(B) Incorrect. Medulloblastoma, though composed of small blue cells, arises in the central nervous system (posterior fossa) in children.
(C) Incorrect. Though neuroblastoma is composed of small blue cells, it typically arises in the adrenal in children.
(D) Incorrect. A chondroblastoma arises in the epiphysis of bone.
(E) Incorrect. An osteoblastoma is essentially just a large osteoid osteoma, often in vertebra.
--------------------------------------------------
Question 147
A 14-year-old African man has a history of multiple episodes of sudden onset of severe abdominal pain and back pain lasting for hours. Each time this happens, his peripheral blood smear demonstrates numerous sickled erythrocytes. A hemoglobin electrophoresis shows 94% Hgb S, 5% Hgb F, and 1% Hgb A2. He now has a painful right hip that is tender to palpation. A radiograph reveals irregular bony destruction of the femoral head. Which of the following infectious agents is most likely responsible for his findings?
A Yersinia pestis
B Clostridium perfringens
C Salmonella, not typhi
D Group B Streptococcus
E Candida albicans
-------------------------------------------------------
(C) CORRECT. Salmonella osteomyelitis is a feature seen in patients with sickle cell anemia. Other organisms that are frequent causes for osteomyelitis with sickle cell anemia include Staphylococcus aureus and gram negatives such as Klebsiella.
(A) Incorrect. This organism is associated with plague, in septicemia, pneumonic, and bubonic (lymphadenitis) forms.
(B) Incorrect. This organism is associated with gas gangrene. In soft tissues, it can be introduced in association with trauma.
(D) Incorrect. This is not a common organism with osteomyelitis, except perhaps in the neonatal period.
(E) Incorrect. This would be a very rare finding with osteomyelitis.
-------------------------------------------------------
Question 148
A 70-year-old man has noted increasing back and leg pain for 3 years. He has greater difficulty hearing on the left. On physical examination he has decreased range of motion at the hips. Radiographs reveal bony sclerosis of the sacroiliac, lower vertebral, and upper tibial regions with cortical thickening, but without mass effect or significant bony destruction. If that weren't enough trouble, he says his hats don't even fit him anymore. He now has orthopnea and pedal edema. Laboratory studies show a serum alkaline phosphatase of 264 U/L. Which of the following conditions is he most likely to have?
A Metastatic adenocarcinoma
B Paget disease of bone
C Renal failure with renal osteodystrophy
D Decreased bone mass
E Vitamin D deficiency
-----------------------------------------------------------
(B) CORRECT. There is both proliferation and destruction of bone that leads to an increase in size of the affected bone and increased blood flow that predisposes to congestive heart failure to account for these findings. Narrowing of bony canals traversed by peripheral or cranial nerves can lead to nerve palsies.
(A) Incorrect. Metastatic disease to bone produces focal lesions, not more diffuse enlargement.
(C) Incorrect. Renal osteodystrophy leads to lesions of osteitis fibrosa cystica admixed with osteomalacia, which are focal in nature.
(D) Incorrect. Osteoporosis leads to decreased bone mass, not an increase in bone size or bony sclerosis.
(E) Incorrect. Osteomalacia has an appearance similar to osteoporosis in adults.
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Question 149
An 18-year-old woman has noted pain and swelling of her right distal thigh associated with activity for the past year. She has no history of any trauma. On examination after performing physical exercise, there is tenderness on palpation above the right knee. Radiographs show an expansile, eccentric, lytic lesion located in the metaphysis of the distal femur that is surrounded by a rim of reactive new bone as a host response. Which of the following diseases is she most likely to have?
A Fibrous dysplasia
B Ewing sarcoma
C Chondrosarcoma
D Osteosarcoma
E Aneurysmal bone cyst
---------------------------------------------------------
(E) CORRECT. The major differential diagnosis for aneurysmal bone cyst is giant cell tumor of bone.
(A) Incorrect. This is a localized, abnormal proliferation of fibrous tissue in bone arranged with haphazard trabeculae of woven bone.
(B) Incorrect. These lesions are diaphyseal.
(C) Incorrect. Chondrosarcomas are more typical of the metaphyseal region.
(D) Incorrect. Osteosarcomas occur in the metaphyseal region.
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Question 150
A 77-year-old man has experienced persistent dull back pain for 4 months, unrelated to physical activity. He has noted a 6 kg weight loss during this time. On physical examination there are no remarkable findings. A CT scan of the spine reveals scattered 0.4 to 1.2 cm bright lesions in the vertebral bodies. Laboratory findings include a WBC count of 6700/microliter with differential of 70 segs, 8 bands, 2 metamyelocytes, 15 lymphs, 5 monos, and 2 nucleated RBCs/100 WBCs, Hgb 11.2 g/dL, Hct 33.3%, MCV 88 fL, and platelet count 89,000/microliter. Serum chemistries include sodium 144 mmol/L, potassium 4.5 mmol/L, chloride 100 mmol/L, CO2 26 mmol/L, urea nitrogen 35 mg/dL, creatinine 3.8 mg/dL, and glucose 78 mg/dL. Which of the following additional laboratory test findings is he most likely to have:
A Blood culture positive for Neisseria gonorrheae
B Parathyroid hormone, intact, of 100 pg/mL
C Serum prostate specific antigen of 35 ng/mL
D Serum calcium of 5.5 mg/dL
E Positive serology for Borrelia burgdorferi
-----------------------------------------------------------------
(C) CORRECT. A prostatic adenocarcinoma should be the first guess (particularly in a male!) with osteoblastic (bone-forming) tumor metastases. Extensive metastases can act as a myelophthisic process that leads to peripheral blood leukoerythroblastosis. His cancer may be causing urinary tract obstruction with renal failure.
(A) Incorrect. The bright areas are osteoblastic metastases, not lytic areas of osteomyelitis.
(B) Incorrect. Hyperparathyroidism should be accompanied by increased bone lucency.
(D) Incorrect. Hypocalcemia is not typically related to bone disease.
(E) Incorrect. Lyme disease can be associated with an arthritis, but not bone lesions.
An otherwise healthy 44-year-old man with no prior medical history has had increasing back pain and right hip pain for the past decade. The pain is worse at the end of the day. On physical examination he has bony enlargement of the distal interphalangeal joints. A radiograph of the spine reveals the presence of prominent osteophytes involving the vertebral bodies. There is sclerosis with narrowing of the joint space at the right acetabulum seen on a radiograph of the pelvis. Which of the following diseases is he most likely to have?
A Gout
B Rheumatoid arthritis
C Osteoarthritis
D Osteomyelitis
E Lyme disease
F Pseudogout
-----------------------------------
(C) CORRECT. Degenerative osteoarthritis is a common and progressive condition that becomes more frequent and symptomatic with aging. There is erosion and loss of articular cartilage with joint space narrowing. There is minimal inflammation.
(A) Incorrect. A gouty arthritis is more likely to be accompanied by swelling, and deformity with joint destruction. The pain is not related to usage.
(B) Incorrect. Rheumatoid arthritis typically involves small joints of the hands and feet most severely, and there is a destructive pannus that leads to marked joint deformity.
(D) Incorrect. Osteomyelitis represents an ongoing infection that produces marked bone deformity, not just joint narrowing.
(E) Incorrect. Lyme disease produces a chronic arthritis, but it is typically preceded by a deer tick bite with a skin lesion. It is much less common than osteoarthritis.
(F) Incorrect. Pseudogout, or calcium pyrophosphate dihydrate deposition disease, is more often a disease of the elderly, accompanied by meniscal calcification and joint space narrowing. There can be acute attacks with marked pain. The knees are most often involved.
-----------------------------------------------
Question 142
An 80-year-old woman has had no major medical problems, but she has never been physically active for most of her life. One day she falls out of bed and immediately notes a sharp pain in her left hip. She is subsequently unable to ambulate without severe pain. Radiographs show not only a fracture of the left femoral head, but also a compressed fracture of T10. Which of the following conditions is she most likely to have?
A Vitamin D deficiency
B Acute osteomyelitis
C Osteogenesis imperfecta
D Osteoporosis
E Polyostotic fibrous dysplasia
F Metastatic breast carcinoma
---------------------------------------------------------------------------
(D) CORRECT. She most likely has osteoporosis of bone with accelerated bone loss leading to the propensity for fractures. Physical inactivity further accelerates bone loss and decreases muscle mass and agility that contribute to falls.
(A) Incorrect. A poor diet could be lacking in vitamin D, though endogenous vitamin D production occurs with sunlight exposure. The findings are those of osteomalacia and are similar clinically to osteoporosis.
(B) Incorrect. An osteomyelitis is not typical at this age and does not usually present as fractures in multiple locations.
(C) Incorrect. This inherited disorder of collagen synthesis is initially diagnosed in fetuses and young children.
(E) Incorrect. This is a rare disorder with that can be seen with McCune-Albright syndrome.
(F) Incorrect. So-called 'pathologic fracture' from weakening of bone by metastases can occur, but such patients are often very ill, with a history of weight loss, and prior bone pain.
--------------------------------------------------------------------------
Question 143
A 51-year-old man has noted right hip pain for the past 3 months. On physical examination he has diminished range of motion of the right hip. A radiograph reveals a 10 x 13 cm mass involving the right ischium of the pelvis. The mass has irregular borders and there are extensive areas of bony destruction along with some scattered calcifications. The lesion is resected, and grossly the mass has a bluish-white cut surface. Which of the following attributes is most likely to describe this mass?
A The most frequent primary tumor of bone
B Usually seen in distal skeletal bones
C More common in females
D Sometimes seen to arise in benign cartilagenous tumors
E Associated with Paget disease of bone
----------------------------------------------------------------------------------
(D) CORRECT. Though probably a sporadic occurrence in the case desccribed here, chondrosarcomas can occur in association with osteochondromatosis.
(A) Incorrect. Osteosarcoma is the most frequent primary malignancy of bone, not chondrosarcoma.
(B) Incorrect. Distal cartilagenous tumors are more likely to be benign, whereas those in a central location are virtually always malignant.
(C) Incorrect. Primary malignancies of bone, including chondrosarcoma, are more common in males.
(E) Incorrect. Some osteosarcomas are associated with Paget disease of bone, but not typically chondrosarcomas.
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Question 144
A 62-year-old man has had back pain for 4 months. No abnormal findings are noted on physical examination. A CBC shows a WBC count of 3700/microliter, hemoglobin 10.3 g/dL, hematocrit 31.1%, MCV 85 fL, and platelet count 110,000/microliter. His total serum protein is 8.5 gm/dl with an albumin of 4.1 gm/dl. A chest radiograph shows no abnormalities of heart or lung fields, but there are several lucencies noted in the vertebral bodies. A sternal bone marrow aspirate is performed and yields a dark red jelly-like material in the syringe. Which of the following cell types is most likely to be numerous on microscopic examination of this aspirate?
A Giant cells
B Fibroblasts
C Osteoblasts
D Metastatic renal carcinoma cells
E Plasma cells
-------------------------------------------------------------------
(E) CORRECT. The patient has multiple myeloma. The bone marrow needle was in a lytic lesion filled with plasma cells. His serum globulin is high as a result of his monoclonal gammopathy.
(A) Incorrect. Giant cells may be seen in a variety of benign and malignant lesions of bone, but this does not explain the hypergammaglobulinemia.
(B) Incorrect. Fibroblasts produce collagen and are more numerous with the gross appearance of firm, white scar tissue.
(C) Incorrect. Osteoblasts are most numerous in repair of bone, and callus is very firm.
(D) Incorrect. Osteolytic metastases of renal cell carcinoma could have the gross appearance described here, but would not account for hypergammaglobulinemia.
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Question 145
A 58-year-old man has the sudden onset late one evening of severe pain in his left great toe. There is no history of trauma. On examination there is edema with erythema and pain on movement of the left 1st metatarsophalangeal joint, but there is no overlying skin ulceration. A joint aspirate is performed and on microscopic examination reveals numerous neutrophils. Over the next 3 weeks, he has two more similar episodes. On physical examination between these attacks, there is minimal loss of joint mobility. Which of the following laboratory test findings is most characteristic for his underlying disease process?
A Hyperglycemia
B Positive antinuclear antibody
C Hyperuricemia
D Hypercalcemia
E High rheumatoid factor titer
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(C) CORRECT. Many patients with gout will have hyperuricemia, but not all. The big toe is the most common joint involved with gout. Acute gouty attacks are associated with intense pain from acute inflammation.
(A) Incorrect. Hyperglycemia is a feature of diabetes mellitus, which is associated with peripheral vascular disease that increases the risk for foot ulcerations and osteomyelitis.
(B) Incorrect. The arthralgias common to many autoimmune diseases with a positive ANA, such as systemic lupus erythematosus, are not usually associated with joint swelling, redness, or deformity.
(D) Incorrect. There can be bone luceny with hyperparathyroidism, but the joints are not greatly affected, nor is there swelling or redness.
(E) Incorrect. Rheumatoid arthritis leads to marked joint deformity, typically of small joints in hands and feet. The pain usually persists for weeks to months.
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Question 146
A 13-year-old boy complains of pain persisting in his left leg for 3 weeks. On physical examination his temperature is 37.9 C. A radiograph of the leg reveals a mass in the diaphyseal region of the left femur with overlying cortical erosion and soft tissue extension. A bone biopsy is performed and the lesion on microscopic examination shows numerous small round blue cells. Which of the following neoplasms is he most likely to have?
A Ewing sarcoma
B Medulloblastoma
C Neuroblastoma
D Chondroblastoma
E Osteoblastoma
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(A) CORRECT. A 'small round blue cell' tumor of bone is Ewing sarcoma, a form of primitive neuroectodermal tumor, commonly seen at this age and in the diaphyseal region of bone.
(B) Incorrect. Medulloblastoma, though composed of small blue cells, arises in the central nervous system (posterior fossa) in children.
(C) Incorrect. Though neuroblastoma is composed of small blue cells, it typically arises in the adrenal in children.
(D) Incorrect. A chondroblastoma arises in the epiphysis of bone.
(E) Incorrect. An osteoblastoma is essentially just a large osteoid osteoma, often in vertebra.
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Question 147
A 14-year-old African man has a history of multiple episodes of sudden onset of severe abdominal pain and back pain lasting for hours. Each time this happens, his peripheral blood smear demonstrates numerous sickled erythrocytes. A hemoglobin electrophoresis shows 94% Hgb S, 5% Hgb F, and 1% Hgb A2. He now has a painful right hip that is tender to palpation. A radiograph reveals irregular bony destruction of the femoral head. Which of the following infectious agents is most likely responsible for his findings?
A Yersinia pestis
B Clostridium perfringens
C Salmonella, not typhi
D Group B Streptococcus
E Candida albicans
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(C) CORRECT. Salmonella osteomyelitis is a feature seen in patients with sickle cell anemia. Other organisms that are frequent causes for osteomyelitis with sickle cell anemia include Staphylococcus aureus and gram negatives such as Klebsiella.
(A) Incorrect. This organism is associated with plague, in septicemia, pneumonic, and bubonic (lymphadenitis) forms.
(B) Incorrect. This organism is associated with gas gangrene. In soft tissues, it can be introduced in association with trauma.
(D) Incorrect. This is not a common organism with osteomyelitis, except perhaps in the neonatal period.
(E) Incorrect. This would be a very rare finding with osteomyelitis.
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Question 148
A 70-year-old man has noted increasing back and leg pain for 3 years. He has greater difficulty hearing on the left. On physical examination he has decreased range of motion at the hips. Radiographs reveal bony sclerosis of the sacroiliac, lower vertebral, and upper tibial regions with cortical thickening, but without mass effect or significant bony destruction. If that weren't enough trouble, he says his hats don't even fit him anymore. He now has orthopnea and pedal edema. Laboratory studies show a serum alkaline phosphatase of 264 U/L. Which of the following conditions is he most likely to have?
A Metastatic adenocarcinoma
B Paget disease of bone
C Renal failure with renal osteodystrophy
D Decreased bone mass
E Vitamin D deficiency
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(B) CORRECT. There is both proliferation and destruction of bone that leads to an increase in size of the affected bone and increased blood flow that predisposes to congestive heart failure to account for these findings. Narrowing of bony canals traversed by peripheral or cranial nerves can lead to nerve palsies.
(A) Incorrect. Metastatic disease to bone produces focal lesions, not more diffuse enlargement.
(C) Incorrect. Renal osteodystrophy leads to lesions of osteitis fibrosa cystica admixed with osteomalacia, which are focal in nature.
(D) Incorrect. Osteoporosis leads to decreased bone mass, not an increase in bone size or bony sclerosis.
(E) Incorrect. Osteomalacia has an appearance similar to osteoporosis in adults.
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Question 149
An 18-year-old woman has noted pain and swelling of her right distal thigh associated with activity for the past year. She has no history of any trauma. On examination after performing physical exercise, there is tenderness on palpation above the right knee. Radiographs show an expansile, eccentric, lytic lesion located in the metaphysis of the distal femur that is surrounded by a rim of reactive new bone as a host response. Which of the following diseases is she most likely to have?
A Fibrous dysplasia
B Ewing sarcoma
C Chondrosarcoma
D Osteosarcoma
E Aneurysmal bone cyst
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(E) CORRECT. The major differential diagnosis for aneurysmal bone cyst is giant cell tumor of bone.
(A) Incorrect. This is a localized, abnormal proliferation of fibrous tissue in bone arranged with haphazard trabeculae of woven bone.
(B) Incorrect. These lesions are diaphyseal.
(C) Incorrect. Chondrosarcomas are more typical of the metaphyseal region.
(D) Incorrect. Osteosarcomas occur in the metaphyseal region.
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Question 150
A 77-year-old man has experienced persistent dull back pain for 4 months, unrelated to physical activity. He has noted a 6 kg weight loss during this time. On physical examination there are no remarkable findings. A CT scan of the spine reveals scattered 0.4 to 1.2 cm bright lesions in the vertebral bodies. Laboratory findings include a WBC count of 6700/microliter with differential of 70 segs, 8 bands, 2 metamyelocytes, 15 lymphs, 5 monos, and 2 nucleated RBCs/100 WBCs, Hgb 11.2 g/dL, Hct 33.3%, MCV 88 fL, and platelet count 89,000/microliter. Serum chemistries include sodium 144 mmol/L, potassium 4.5 mmol/L, chloride 100 mmol/L, CO2 26 mmol/L, urea nitrogen 35 mg/dL, creatinine 3.8 mg/dL, and glucose 78 mg/dL. Which of the following additional laboratory test findings is he most likely to have:
A Blood culture positive for Neisseria gonorrheae
B Parathyroid hormone, intact, of 100 pg/mL
C Serum prostate specific antigen of 35 ng/mL
D Serum calcium of 5.5 mg/dL
E Positive serology for Borrelia burgdorferi
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(C) CORRECT. A prostatic adenocarcinoma should be the first guess (particularly in a male!) with osteoblastic (bone-forming) tumor metastases. Extensive metastases can act as a myelophthisic process that leads to peripheral blood leukoerythroblastosis. His cancer may be causing urinary tract obstruction with renal failure.
(A) Incorrect. The bright areas are osteoblastic metastases, not lytic areas of osteomyelitis.
(B) Incorrect. Hyperparathyroidism should be accompanied by increased bone lucency.
(D) Incorrect. Hypocalcemia is not typically related to bone disease.
(E) Incorrect. Lyme disease can be associated with an arthritis, but not bone lesions.
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