A 12-YEAR-OLD boy developed a sore throat and fever 6 weeks before presenting with weight loss, right-sided facial swelling, and a tender left-sided neck mass that was unresponsive to antibiotics. A tracheostomy was required to maintain his airway. His facial and lingual swelling resolved dramatically with glucocorticoids, but following hospital discharge he developed severe myalgias and arthralgias, primarily in his legs.
Fever and right-sided facial and periorbital edema recurred (Figure 1). A few painful erythematous nodules were noted on his shins and feet (Figure 2). Abnormal laboratory test results included a white blood cell count of 27.4×109/L with 84% neutrophils, a platelet count of 970×109/L, a hematocrit of 25%, an erythrocyte sedimentation rate of 140 mm/h, a C-reactive protein level of 0.18 g/L, and an antistreptolysin O titer of 500 Todd U. Within 12 hours of intravenous glucocorticoid administration he dramatically improved (Figure 3). Skin biopsy