Objective: To determine the frequency of organisms causing onychomycosis in a tertiary care hospital.

Study Design: Cross-sectional study

Setting and Duration: The Department of Dermatology, PNS Shifa Hospital, Karachi for duration of six months from 1st September 2019 to 28th February 2020

Material and Methods: Total 395 patients were included. Affected nail was cleaned with 70% alcohol and nail clipping was done. Scrapings were collected from distal portion of nail plate, the nail bed and undersurface of the nail. In case of multiple nail involvement, the nail that was most severely affected was selected. The culture plates were put to incubation and observed for 4 weeks period for the presence of growth. Descriptive statistics were calculated. Stratification was done. Poststratification chi-square test was applied. P-value ≤0.05 was considered as significant.

Results: There were 63.8% male and 36.2% female patients. Color change of nail was observed in 94.9% cases, subungual hyperkeratosis in 28.6% cases, distal onycholysis in 24.6% cases, total nail plate dystrophy in 22% cases, partial nail plate dystrophy in 11.6% cases, and transverse ridges in 21.8% cases. Total 82.8% cases were classified as dermatophyte, 5.3% as yeast and 11.9% as non-dermatophytic mould.

Conclusion: In conclusion, our study results showed that most prevalent mycological type of isolate was dermatophyte, followed by non-dermatophytic mould, and yeast.

Keywords: Frequency, Organisms, Onychomycosis