Mycological Profile and Prevalence of Superficial Mycoses Agents: A Study from North India

Abstract

Background: Superficial fungal infections are one of the commonest human infections. Causative agents of such infections may vary from yeasts like Candida species, Trichosporon species to dermatophytes and non-dermatophyte moulds. Fungal culture therefore, holds importance in identification and characterization of a fungal isolate, so that proper diagnosis can be made and correct treatment is instituted. Our objective was to study the etiology of the superficial fungal infections in patients presenting to the dermatology department in a tertiary care hospital in New Delhi. Materials and Methods: A total of 340 skin and hair samples from patients clinically suspected to have superficial fungal infection of skin and hair were microscopically examined and cultured over a period of 2 years. The percentage and frequency distribution of etiological fungal agents was studied. Also the performance of the culture and microscopy as methods of detecting fungal agents was statistically compared using Kappa and proportions of positive and negative agreement as well as McNemar’s Chi-squared value. Corresponding p-values were also calculated for both kappa and Chi-squared values. The analysis has been done using Epitools. Results: Of these, 57.6% were positive for fungal elements by microscopic examination and the overall positivity of fungal infection was 70%. Out of 238 culture positive samples, 72.7% grew dermatophytes and 27.3% grew non-dermatophytes (including 16.8% yeasts and 10.9% non-dermatophyte moulds. Trichophyton mentagrophytes was the commonest (60.7%) dermatophyte isolated, followed by T. rubrum (17.3%), T. violaceum (7.5%), T. tonsurans (7.5%), T. verucosum (2.9%), Microsporum gypseum (1.2%) and M. canis (0.6%). Among the isolated non-dermatophytes, Candida species was the commonest (50.8%) majority of which were C. albicans, other non-dermatophytes included moulds like Fusarium spp. (6.1%), Aspergillus fumigatus (4.6%), A. flavus (3.1%), Alternaria spp. (3.1%), Acremonium spp. (3.1%), A. niger (3.1%) etc. and yeasts like Trichosporon spp. (10.8%). Conclusion: Dermatophytosis still remains the most common type of fungal infection involving skin and its appendages but non-dermatophytes are also slowly emerging as the causative agents for these infections.