Background and Objective: Otitis externa is a common condition affecting the external auditory canal. Predisposing factors implicated in the pathogenesis of the condition includepreexisting aural disease, genetic factors, infection, trauma, and climatic conditions. Bacteria are the most common cause of infection and fungi play a smaller but significant role in the disease.
Otomycosis is characterized by inflammation, pruritus, pain, and scaling, usually in a unilateralpattern.
Otomycosis has a worldwide distribution with a higher prevalence in the hot, humid, and dusty climate of the tropical and subtropical regions. The objectives of this study were to determine the prevalence of mycotic infections in inflammatory conditions of the ear and to determine fungalspecies responsible for otitis. Materials and Methods: The study was conducted on 70 cases who presented with symptomsof otitis from September 2000 to December 2003. Patients were admitted in ENT clinic of Amir- Al-Momenin hospital. To determine the species of fungi present in the ears, samples were collectedfrom the external auditory meatus using sterile swabs for mycological examination. These specimenswere processed at the department of microbiology. A part of the samples was used for direct microscopy in 10% potassium hydroxide and Gram’s method was employed to stain the smearsfrom all specimens cultured on Sabouraud Dextrose agar with chloramphenicol (Sc). To identifyyeasts, assimilation tests were used by API 20C AUX. Results:
Otomycosis was diagnosed in 8 (11. 4%) of 70 investigated patients. Yeast speciesresponsible for otitis were classified as belonging to the genus Candida. The most frequent fungal species detected were
Candida parapsilosis (5 cases),
Candida glabrata (2 cases), Candida.krusei (1 case). In other patients, the bacterial agents isolated were as follow as: Pseudomonas aeruginosa,Staphylococcus aureus, Streptococcus, S. epidermidis, S. saprophyticus, and Enterobacteriaceae.Conclusion: In the present study fungi on average were the etiological factor of otomycosis in11.4% of cases. A similar rate for ear fungal infections was observed by Kurnatowski and Filipiak. Inorder to solve the therapeutic difficulties and to apply the most adequate treatment, comprehensivemycological examinations, often avoided during routine clinical procedures, must be performed. Underestimation and sometimes ignorance of the role of these pathogens in the etiology of diseases of the ear may lead to a prolonged and/or ineffective treatment of patients.