A 50-year-old man comes to the office due to a 4-month history of achy joint pain in the lower back, shoulders, hips, and knees. The pain increases with activity, and he has no morning stiffness. The patient also has excessive sweating, polyuria, and erectile dysfunction. Medical history is unremarkable. The patient has a 25-pack-year smoking history and drinks moderate amounts of alcohol on social occasions. Blood pressure is 150/90 mm Hg, pulse is 80/min, and respirations are 16/min. Examination shows crepitus on passive movement of the knee joints. There is increased interdental spacing and an enlarged tongue, and the remainder of the examination is normal. Plain radiography of the hand reveals widening of the joint spaces, osteophytes, and thickened soft tissues. Laboratory evaluation reveals low testosterone and hyperglycemia. What is the most likely diagnosis?

Question

A 50-year-old man comes to the office due to a 4-month history of achy joint pain in the lower back, shoulders, hips, and knees.  The pain increases with activity, and he has no morning stiffness.  The patient also has excessive sweating, polyuria, and erectile dysfunction.  Medical history is unremarkable.  The patient has a 25-pack-year smoking history and drinks moderate amounts of alcohol on social occasions.  Blood pressure is 150/90 mm Hg, pulse is 80/min, and respirations are 16/min.  Examination shows crepitus on passive movement of the knee joints.  There is increased interdental spacing and an enlarged tongue, and the remainder of the examination is normal.  Plain radiography of the hand reveals widening of the joint spaces, osteophytes, and thickened soft tissues.  Laboratory evaluation reveals low testosterone and hyperglycemia.  What is the most likely diagnosis?

Quizplus · Accepted Answer

11ec25c8_d817_d4f3_bc81_076802983549_MD0003_00 This patient has characteristic features of acromegaly, including arthralgias, jaw widening (increased interdental spaces), and macroglossia. Acromegaly is caused by excessive production of growth hormone (GH), usually by a pituitary somatotroph adenoma. Enlarging adenomas can also cause decreased secretion of other pituitary hormones (eg, gonadotropins, leading to erectile dysfunction and low testosterone). In addition to causing hyperglycemia (eg, polyuria) and increasing metabolic rate (eg, hyperhidrosis), excess GH directly and indirectly (via release of insulin-like growth factor-1 from the liver) leads to overgrowth of tissues, including bone, cartilage, and visceral organs. insulin-like growth factor-1 Joint involvement is common and often involves both axial and appendicular skeletons. GH causes hyperplasia of articular chondrocytes and synovial hypertrophy, which may be visible on x-ray as joint space widening. In later stages, cartilage degeneration typically occurs, leading to clinical and radiographic findings resembling osteoarthritis. Spinal involvement may lead to kyphoscoliosis. Treatment (eg, transsphenoidal surgery) can minimize arthropathy in the hypertrophic stages but will not reverse degenerative changes. (Choice B) Macroglossia is a characteristic manifestation of amyloid light-chain amyloidosis in plasma cell disorders. Patients may have polyarticular arthritis with widening of the joint spaces and thickening of soft tissues. However, hyperhidrosis and dental malocclusion are more typical of acromegaly. (Choice C) Hereditary hemochromatosis-associated arthropathy most commonly presents as degenerative arthritis involving the second and third metacarpophalangeal joints. Periarticular osteophytes may be seen on x-ray, but joint spaces are narrowed; close inspection may reveal deposition of calcium pyrophosphate dihydrate in articular cartilage (chondrocalcinosis). Cranial abnormalities are atypical. Periarticular osteophytes chondrocalcinosis (Choice D) Paget disease of bone is characterized by excessive, disordered bone formation; affected bone weakens, leading to bowing, fracture, and arthritis of adjacent joints. However, findings are focal and asymmetric; x-rays reveal mixed lytic-sclerotic lesions and thickening of cortical and trabecular bone. Visceral enlargement (enlarged tongue) and hyperhidrosis are not typical. mixed lytic-sclerotic lesions (Choice E) Hypertrophic osteoarthropathy is a paraneoplastic syndrome of pulmonary malignancy, primarily adenocarcinoma. It is characterized by bone and soft tissue enlargement in the distal extremities. Manifestations include clubbing, arthropathy, periostosis of long bones, and joint effusions; cranial abnormalities are not common. Educational objective: Joint involvement in acromegaly is common and often involves the axial and appendicular skeletons. Excessive growth hormone causes hyperplasia of articular chondrocytes and synovial hypertrophy, which may be visible on x-ray as joint space widening. In later stages, cartilage degeneration may lead to clinical and radiographic findings resembling osteoarthritis.

A 50-Year-Old Man Comes to the Office Due to a 4-Month