Epidemiology and predictive factors of fungal malignant otitis externa

Abstract

Context and Aims: A recent upsurge of severe fungal forms of malignant otitis externa (MOE) has been recorded. Understanding the misleading clinical aspect of the disease allows earlier diagnosis, avoiding inadequate treatments that may complicate the adapted management. Our objective was to study the epidemiological and clinical aspects of the MOE in our department and to analyze some predictive factors of the fungal form of the disease. Materials and Methods: Medical data of 100 patients treated for MOE between 2004 and 2013 were retrospectively reviewed. Epidemiological findings were recorded. Clinical aspects and presentations were studied and noted. Analysis of some predictive factors of the fungal form of the disease was done. Results: Incidence of MOE was 10 new cases every year. The average age was 67.41 years, and the sex ratio was 0.92. All patients have diabetes. Otalgia was a constant symptom. Otorrhea was noted in 63% of cases. Hearing impairment and tinnitus were noted, respectively, in 23% and 18% of cases. Prior antibiotherapy was recorded in 33% of cases for a mean period of 21 days. Stenosis of the external auditory canal was observed in 92% of cases. Granulation tissue was present in 55% of patients. Twenty patients presented peripheral facial nerve palsy. Four others presented palsies of the VI, IX, and X nerves. Forty-one patients had mycological sampling. Twenty-six among them were diagnosed with fungal MOE. Identifying fungal agent took a mean delay of 40 days. Aspergillus and Candida were incriminated each one in half of the cases. Male gender and prior quinolone administration were predictive factors of fungal MOE with, respectively, P = 0.006 and P = 0.06. After multivariate analysis, only male gender was significantly correlated to fungal growth (P = 0.032). Conclusion: Management of fungal forms is challenging due to difficult and late diagnosis. An early mycological sampling is advisable with special attention to males and patients with prior quinolone administration.