Infection-Triggered Presumed Isolated Necrotizing Digital Vasculitis Presenting as Systemic Vasculitis

Systemic necrotizing vasculitides are life-threatening disorders that require prompt immunosuppressive therapy.However, a broad spectrum of infectious diseases can closely mimic systemic vasculitis, presenting with cutaneous small-or medium-vessel involvement and digital necrosis. 1,2Distinguishing primary immune-mediated vasculitis from infection-driven vasculitis is crucial, as inappropriate immunosuppression in unrecognized infections may worsen outcomes. 3We report a case of a child with infection-triggered presumed isolated digital necrotizing vasculitis, initially raising concern for systemic vasculitis.A previously healthy 9-year-old boy presented to the pediatric emergency department with a 5-day history of fever up to 38 C and bilateral swelling of the feet.Initial evaluation by orthopedics revealed no musculoskeletal pathology.Empirical oral amoxicillinclavulanate was started.Despite treatment, the patient returned with progressive discoloration of the digits of both feet and the left hand (Figure 1).The parents had a second-degree consanguineous marriage, but there was no known family history of autoimmune or thrombotic disorders.On physical examination, a 2/6 systolic ejection murmur was audible.Gangrenous discoloration involved the digits of the left hand, left foot, and right foot, while all peripheral pulses were palpable bilaterally.The remainder of the systemic examination was unremarkable.