Objective: To determine the role and pattern of non-dermatophyte moulds as causative agents of onychomycosis.
Study design: Case series.
Place and duration of study: Department of Microbiology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from November 2009 to July 2010.
Methodology: Nail clippings and nail scrapings were obtained from abnormal looking nails with treatment and detection failure for onychomycosis. Microscopic (40% potassium hydroxide mounts) examination and culture on Sabouraud's dextrose agar (SDA), SDA containing chloramphenicol, and SDA containing actidione and chloramphenicol were used for species identification.
Results: Non-dermatophyte moulds were isolated from 32 out of the total 47 culture positive cases (68%). Alternaria alternata was the commonest species (46%). Dermatophytes were isolated from only 7 patients (15%) belonging to genus Trichophyton. Yeasts were isolated in 8 (17%). There was no fungal growth in 53% of cases.
Conclusion: The non-dermatophytes should be considered important in evaluating the culture negative cases for dermatophytes as well as those cases ending up in treatment failure after empirical treatment for dermatophyte infections.