Etiologic Agents of Otomycosis in the North-Western Area of Iran

Otomycosis is a superficial fungal infection often involves the pinna and external auditory canal. It is a pathologic condition, with Candida and Aspergillus, the most common fungal species. It is common worldwide but more prevalent in tropical and subtropical countries. The aim of this study was to determine the etiologic agents and local epidemiologic pattern of otomycosis in northwest Iran. A series of 140 patients with clinically symptomatic otomycosis were studied in 21 cities, towns, and villages throughout northwest Iran between 2009 and 2011. Clinical samples were collected by swabs and then assessed by mycological investigation. Otomycosis was diagnosed in 129 cases (92%, 76 male, 53 female) with the highest prevalence of cases occurring in males between 21 - 40 years of age. From an etiological point of view, 116 patients (90%, 21 - 40 years old) were infected by saprophytic mold and 9 patients (7%) were infected by yeast. Three cases (2%) involved dermatophytes, and in one case (1%) the subject was infected with Eurotium (the perfect stage of Aspergillus fumigatus). Aspergillus niger was the most common mold that was isolated, followed by A. flavus, A. fumigatus, Penicillium spp., Fusarium spp., and Rhizopus spp. A total of 2 yeasts belonging to genus Candida, C. albicans and C. tropicalis, were isolated. Our study showed a high prevalence of otomycosis in the northwestern area of Iran. As such, proper diagnosis and treatment by aseptic techniques for this disease is urgently needed.