A 45-year-old man comes to the office due to a 6-month history of headache, sweating, and pain in his lower back, knees, and small joints of his hands. The pain increases with physical activity. He is unable to remove his wedding ring due to swollen fingers. The patient has also experienced excessive urination and loss of libido. Examination shows a prominent jaw and enlarged supraorbital ridges. The patient's hands are notably broad with thickened fingers. Multiple skin tags are noted on the nape of the neck. Laboratory evaluation reveals low serum testosterone levels. Which of the following is the most likely underlying cause of this patient's joint symptoms?

Question

A 45-year-old man comes to the office due to a 6-month history of headache, sweating, and pain in his lower back, knees, and small joints of his hands.  The pain increases with physical activity.  He is unable to remove his wedding ring due to swollen fingers.  The patient has also experienced excessive urination and loss of libido.  Examination shows a prominent jaw and enlarged supraorbital ridges.  The patient's hands are notably broad with thickened fingers.  Multiple skin tags are noted on the nape of the neck.  Laboratory evaluation reveals low serum testosterone levels.  Which of the following is the most likely underlying cause of this patient's joint symptoms?

Quizplus · Accepted Answer

11ec160b_390a_24ab_9249_0f9f7b83186d_MD0001_00 This patient has common features of acromegaly, including coarsening of facial features (eg, brow protrusion, prognathism), broadening of the hands, and skin involvement (eg, skin tags, hyperhidrosis). Acromegaly is caused by excessive production of growth hormone (GH) and is most often due to a pituitary somatotroph adenoma. Excess GH both directly and indirectly (via release of insulin-like growth factor-1 from the liver) leads to overgrowth of many tissues, including bone, cartilage, and visceral organs. Acromegaly can affect the joints in both the axial and the appendicular skeleton. Excessive GH causes hyperplasia of articular chondrocytes and synovial hypertrophy, which may appear on x-ray as widening of the joint space. As acromegalic arthropathy continues, there is degeneration of articular cartilage and periarticular bone resembling osteoarthritis. Complications of the pituitary mass itself include headache, visual field defects (compression of optic chiasm), and abnormalities of other pituitary hormones. Hypogonadism can occur secondary to hyperprolactinemia (from disrupted negative regulation of prolactin secretion) or directly due to compression of pituitary gonadotrophs. (Choice A) Hereditary hemochromatosis (HH) can cause arthritis due to accumulation of iron in the articular cartilage and synovium. Although HH can also cause central hypogonadism, this patient's skeletal and facial features are more consistent with acromegaly. (Choice B) Crystal deposition arthritis typically presents initially with acute inflammatory monarthritis at the first metatarsophalangeal joints and knees (gout), or knees, wrists, shoulders, and elbows (pseudogout [ie, calcium pyrophosphate deposition arthritis]). These disorders would not cause facial changes or hypogonadism. (Choice C) Sarcoidosis is characterized by the formation of noncaseating granulomas in various tissues. Sarcoid arthropathy often occurs acutely in association with erythema nodosum and hilar adenopathy (Lofgren syndrome); chronic arthritis is less common and usually occurs in patients with significant pulmonary disease. (Choice E) Rheumatoid arthritis (RA) involves a complex inflammatory response, culminating in an influx of monocytes that differentiate into inflammatory macrophages in the synovium. RA commonly presents with chronic swelling of the metacarpophalangeal joints but does not cause enlargement of the supraorbital ridges or jaw. Educational objective: Acromegaly can affect the joints in both the axial and the appendicular skeleton. Excessive growth hormone and insulin-like growth factor-1 cause hyperplasia of articular chondrocytes and synovial hypertrophy, leading to later degeneration of articular cartilage and periarticular bone.

A 45-Year-Old Man Comes to the Office Due to a 6-Month