Abstract
A 72-year-old man presented with an erythematous, painful, swollen, and blistering left hand associated with a systemic fever. The patient was diagnosed with microscopic polyangiitis and was receiving steroid therapy from a year before the incident. Based on a clinical diagnosis of necrotizing fasciitis, emergency surgery was performed within 2 days after the onset. β-Hemolytic Streptococcus group A was isolated from a culture of the blood and wound. Radical debridement and high-dose penicillin and clindamycin therapy successfully saved the patient's life and affected limb except for the second finger on his left hand, which was completely necrotic. However, the function of the left hand was seriously decreased and did not recover. The important point to note in this case was the preexisting vasculitis neuropathy due to microscopic polyangiitis. The severe postoperative dysfunction of the hand was considered to be due to ischemic neuropathy that was aggravated by compartmental syndrome and microvascular thrombosis. In conclusion, necrotizing fasciitis of an extremity with underlying vasculitis neuropathy can lead to a poor functional prognosis of the limb.