Necrotising otitis externa: A single centre experience

Abstract

Introduction: Necrotising otitis externa (NOE) is a rare infection of the ear canal with frequent bone erosion. This study's objective is to describe the different features of NOE as well as its management in an ear-nose-throat department. We also tried to identify the particularities of the fungal infection.

Patients and methods: It is an observational cohort that included all the patients hospitalised for the management of NOE. The study was carried out in the ear-nose-throat Department of Mahdia University Hospital in Tunisia between January 2006 and december 2019.

Results: A total of 40 patients were included. The mean age was 65 ± 12.9 years and the sex ratio was 0.9. Ninety percent of the patients included were diabetics. The most common signs found were oedema of the external canal (97.5%) and auricular discharge (92.5%). The main pathogen isolated was Pseudomonas aeruginosa (61.7%). Fungi were isolated in 9 cases (26.47%). Computed tomography was performed for 32 patients (80%). Bone erosion was seen in 26 cases (81.3%). The main complications were cerebral venous thrombosis, retropharyngeal abscess and cerebral empyema. Thirty one patients received only antibiotics, 2 received only antifungal treatment, and 7 received both antibiotics and antifungal treatment. All patients had a favorable outcome. Univariate analysis showed a higher median erythrocyte sedimentation rate was associated with fungal infections. No other differences were noted.

Conclusion: Our management protocol seems to be efficient since all patients had initial favorable outcome. A higher median erythrocyte sedimentation rate was associated with fungal infections.

Keywords: Diagnosis; Fungi; Otitis externa; Pseudomonas; Therapeutics.

Fig. 1

A. Axial cervical CT image: retropharyngeal abscess (black arrow) with parapharyngeal extension and internal jugular vein thrombosis (white arrow) complicating a necrotising external otitis. B. Axial CT image: thickening and enhancing soft tissue of the external canal (black arrow) with a subluxation and arthritis of the temporo-mandibular joint (white arrow). C. Axial CT image: Tympanic part of the temporal bone lysis.