Prevalence of Onychomycosis by Non Dermatophyte Molds in a Tertiary Care Hospital in Kolkata , West Bengal, India

Background and study aim: Onychomycosis is infection of dermatophytes and Candida sp, and unusually by non-dermatophyte molds (NDM). These NDM are opportunistic fungus seen in plant & soil. Literature on nail mycosis classifies the onychomycosis as Distal and Lateral Subungual, White Superficial, Proximal Subungual, Total Dystrophic and secondary onychomycosis. The aim of this study is to determine the prevalence of non-dermatophyte Molds causing onychomycosis. Patients and Methods: Samples from clinical nail mycosis cases were studied in our Mycology dept. over a period of 1 year from January, 2023 to December, 2023. After informed consent, history-taking and patients' examination, the samples were evaluated by KOH wet mount, culture in SDA and SDCA media at 25°C and 37°C, Slide Culture, LPCB wet mount etc. The data were analyzed using counts and percentages in MS Excel. Results: Out of 114 positive culture 32 cases (28.07%) of onychomycosis was by NDM. The most affected age group of NDM Onychomycosis ranged from 25-60 years (22 patients, 68.75%) and females were more commonly affected (18 cases, 56.25%). The risk factors mostly may be poor socio-economic status with occupation of manual labourers. Total NDM nail mycosis diagnosed were Talaromyces spp - 8 cases (25%), Fusarium spp.-6 cases (18.75%), Mucor spp.-4 cases (12.5%), Rhizopus spp. - 4 cases (12.5%) and 2 cases(6.25%) each of Medicopsis romeroi, Hortaea werneckii, Trichosporon spp., Paecilomyces spp. & Bipolaris spp. Conclusions: Onychomycosis by unusual fungus were found in 28% cases and Total Dystrophic Onychomycosis was present in 62.5% cases. The most frequent NDM were : Talaromyces spp. and Fusarium spp.