Pyoderma gangrenosum masquerading as necrotizing fasciitis.

Necrotizing fasciitis is a fulminant advancing soft tissue infection characterized by widespread fascial necrosis, which can result in significant morbidity and even death. This condition requires prompt diagnosis and aggressive management with extensive surgical debridement and appropriate antibiotic coverage. Pyoderma gangrenosum, in contrast, is a noninfectious inflammatory condition of the skin that typically does not require surgical management. Both conditions can present with extensive ulceration and tissue necrosis, and close clinical-pathologic correlation is required to make the appropriate diagnosis. We present a case in which the diagnosis of pyoderma gangrenosum was initially elusive and serves to illuminate the diagnostic pitfalls in dealing with these entities.