Otomycosis at Fann Hospital in Dakar (Senegal): Prevalence and Mycological Study

Abstract

Otomycosis are auricular infections caused by microscopic fungi which develop essentially in the external ear canal. Their incidence has increased these past years with the emergence of predisposing factors such as the repetitive use of broad -spectrum antibiotics. The objectives of this study were to determine the prevalence of otomycosis at Fann National University Hospital in Dakar and to identify the fungal species responsible for that. This descriptive retrospective study held from October 2011 to December 2017 at 136 patients with clinically suspected otomycosis. External auditory canal exudates collected with swabs in each patient were observed by direct microscopic examination and cultured in Sabouraud Chloramphenicol medium with and without Actidione at 30-37°C. The strains were identified on the basis of macroscopic, microscopic and physiological characteristics. The mycological examination was positive in 59 patients, that is to say, a prevalence of 43.4%. The positivity rate was significantly higher among women (52.6%) than among men (31%) (p=0.012). This rate was significantly higher among patients suffering from otalgia (75.7%) than among others (p=0.023). On the mycological plan, Aspergillus fumigatus and Candida albicans were the species the most isolated (26.3%) followed by Aspergillus niger (22.8%). These results show that fungal agents have an important place in the etiologies of the external otitis at Fann Hospital CHNU. Hence the interest of the mycological diagnosis for a better treatment of patients.