Mycological profile of subcutaneous skin biopsy samples in suspected subcutaneous mycosis, Are we missing some fungi? A tertiary care hospital based study

Abstract

Subcutaneous mycosis includes a heterogeneous group of fungal infections that develop at the site of transcutaneous trauma. A rise in surviving population of individuals with co-morbidities together with lapses in infection control practices especially in rural India has led to emergence of myriad species of fungi causing such infections in recent years. This poses a diagnostic challenge to the clinicians. We therefore felt a need to study the mycological profile of subcutaneous tissue biopsies suspected of fungal etiology in our hospital setup. This was a Retrospective cross-sectional observational study conducted for a period of 4 years from Jan 2015 to Jan 2019 in the Department of microbiology, Government medical College Srinagar. A total of 148 specimens of subcutaneous tissue biopsies of patients suspected of localized fungal Infection were processed by microscopy and culture for fungi. Among a total of 148 subcutaneous tissue biopsy samples 76 (51%) were positive for fungi on KOH and culture. Mycological profile revealed that majority of fungi were Dermatophytes (n=22; 29%) and Yeasts (n=21; 28%). Third most common causative fungi isolated were Chromoblastomycetes (n=8; 11%), Phaeohyphomycetes (n=8;11%) and Aspergilli (n=8;11 %) comprising, A.fumigatus (n=11) and A.terreus (n=03), followed by Hyalohypomycetes (n=4;5%), sporotrichosis (n=3;4%) and Zygomycetes (n=4 ;5.3%). : Dermatophytes and yeasts are emerging subcutaneous fungal infections. Active surveillance for all types of fungal infections should be done at all levels to address knowledge gaps that exist in etiology, pathogenesis and manifestations of fungal diseases of skin and subcutaneous tissue.