Zygomycotic necrotizing fasciitis in immunocompetent patients: a series of 18 cases.

Necrotizing fasciitis is most often associated with bacterial infections. Zygomycosis is an uncommon infection causing necrotizing fasciitis. We report 18 such cases of zygomycotic necrotizing fasciitis, of these, 15 were immunocompetent. Of the eight cases cultured, five were positive for Apophysomyces elegans. A retrospective case review conducted at a tertiary referral center, from 1998 to 2004, 18 cases of fungal necrotizing fasciitis were diagnosed based on histomorphology of fungal organisms; and in few of the cases diagnosis was supported by mycologic culture reports. Of the total of 18 cases, culture report was available in eight cases, and out of which five of them grew A. elegans. Fifteen patients were immunocompetent. Clinical presentation, mycologic findings and histopathologic results were evaluated. A review of the literature pertaining to A. elegans infection was also done. Histopathologic examination showed broad, predominantly aseptate and occasional pauciseptate, thin-walled fungal hyphae with occasional angioinvasion. To the best of our knowledge, this is the first largest series of zygomycotic necrotizing fasciitis from India. Herein, we present data on 18 cases of necrotizing fasciitis assosiated with zygomycosis. Most of the cases in our series were immunocompetent. Nonsuppurative necrosis with presence of typical fungal profiles was important histologic feature. Zygomycosis must be considered in the differential diagnosis not only in immunocompromised patients but also in the absence of any underlying disorders.