RESUMEN
OBJECTIVE: Otomycosis is a fungal infection, which leads to a damage of the external auditory meatus. The disease is worldwide in distribution but is said to be more common in tropical countries. Though otomycosis presumably occurs frequently in Africa, reports on its incidence and etiology are rare from Côte d'Ivoire. The objective of this study was to evaluate the prevalence of the disease and to identify aetiological agents as well as the risk factors. MATERIAL AND METHODS: A cross-sectional study was carried out in the Otorhinolaryngology Department of the University Teaching Hospital of Yopougon from September 2007 to February 2008. For laboratory investigation, specimens were collected by means of a sterile swab. Samples were inoculated on Sabouraud's Dextrose Agar with and without antibiotics and incubated at 30°C for a period of 1 to 2 weeks. Identification was performed by direct microscopic examination on Cotton Blue Mount preparation and slide culture examination was used for differentiation of morphology. Biotyping was performed using Carbohydrate Fermentation tests, Carbohydrate Assimilation Tests (galerie Api 20 CAux TM - Sanofi Pasteur), Germ tube Test, detection of chlamydospore formation on corn meal agar. RESULTS: A total of 110 patients (sex-ratio=1.2) with suspected cases of otomycosis were investigated. Itching, otalgia, and hypoacusis were the symptoms reported by the patients and the apparent signs were debris in the ear, scabs and inflammation of the external auditory meatus. Of these, 88 cases (80%) were confirmed specifically of mycotic etiology on the basis of positive culture with 92 isolates consisting of yeasts (65.2%) and moulds (34.8%). The predominant etiological agents were Aspergillus flavus (28.4%), Candida guilliermondii (19.3%) and Candida parapsilosis (18.2%). The predisposing factors included previous otological pathology (P=0.010), frequent scratching of the external ear canal and use of ear drops (RR=3.47; IC 95%=1.3-9.27). CONCLUSION: This study revealed the great prevalence of otomycosis in Abidjan, some predisposing factors and the aetiological agents. Management of otomycosis must include mycological examination for diagnosis and information for changing behaviour patterns leading to infection.