Necrotic cellulitis. A localized form of septic vasculitis

Cutaneous biopsy specimens from two patients with localized, bacterial, necrotic cellulitis showed a neutrophilic vasculitis with fibrin thrombi, changes indistinguishable from those seen in a third patient with bacterial septicemia. Additional clinical information may be needed before a definitive diagnosis of localized or systemic septic vasculitis can be made with certainty. The clinical and microscopic features of the lesions and their pathologic mechanisms are discussed.