A 65-year-old woman, who was confined to a wheelchair because of severe rheumatoid arthritis, was concerned about nodules that had erupted on her fingers and hands during the previous 3 weeks (A). Her medical history included colon cancer, chronic renal insufficiency, anemia, and hypertension. The nonpruritic nodules were painful when they began to form under the skin; however, once they erupted, the pain disappeared. Four firm, irregular nodules at various stages of development were noted on the dorsa of the fingers and hands. One of the lesions had exuded a yellow-white chalky material from several locations. The patient reported the occurrence of similar nodules in the past; 8 months earlier, a lesion erupted over the left fifth metacarpophalangeal joint, and more recently, a nodule developed over the ulnar surface of the left forearm. Both lesions discharged moist, yellow material and resolved spontaneously within several days. The patient’s medical history raised the possibility of cutaneous calcium deposition. However, roentgenograms of the hands revealed osteopenia and lytic lesions around the joints but no calcium deposits. Erosive and cystic changes were demonstrated at the proximal interphalangeal joints of the second through fifth fingers; similar changes were more prominent at the second and third metacarpophalangeal joint space of the right hand (top row) than of the left (bottom row). The diagnosis of rheumatoid nodules was confirmed clinically. Rheumatoid nodules are found in approximately one third of patients with rheumatoid arthritis. Usually, they are associated with more severe disease and a high rheumatoid factor titer. These lesions also occur in about 5% of persons with systemic lupus erythematosus. Most often located over bony prominences or extensor surfaces—notably on the forearms, elbows, knuckles, feet, and knees—the nodules tend to be deep and asymptomatic. The presentation of eruptive nodules in this patient was atypical. Intralesional corticosteroids were injected into the largest nodule, after which all of the developing and fully developed lesions disappeared completely. At the 4-month follow-up, no recurrence of lesions was noted despite the patient’s refractory arthritis.

(Case and photographs courtesy of Drs Jessica Krant and Yelva Lynfield.)