Malignant (necrotizing) externa otitis: the experience of a single hyperbaric centre

Abstract

Introduction: Malignant otitis externa (MOE) is a potentially life-threatening infection of the soft tissues of the external ear, quickly spreading to involve the periosteum and bone of the skull base. Treatment includes antibiotics and eventually surgery. Hyperbaric oxygen treatment (HBOT) has been proposed as an adjunctive therapy. However, in the tenth consensus conference, this disease was considered as a non-indication for HBOT. The aim of this study was to evaluate the effectiveness of HBOT in MOE treatment.

Methods: Retrospective and observational study was conducted of patients with MOE treated in our centre. Staging of the disease was made according to the clinicopathological classification system.

Results: From March 1998 to November 2016, 16 patients were referred. 6% patients were on stage 1 of the disease at the time they were referred, 20% in stage 2, 7% in stage 3a, 13% in stage 3b and 53% in stage 4. Seven (43.75%) patients had VII nerve palsy and three (18.75%) patients had multiple nerve palsy. Average length of symptoms of disease was 5 months (maximum 11 months). Average number of sessions was 33 and the length of hospitalization prior to HBOT (median 90 days) was significantly longer than the time between beginning HBOT and cure (p = 0.028, Wilcoxon signed rank test). There were no fatalities due to MOE and all patients were considered free of disease after HBOT.

Conclusion: HBOT was well tolerated and revealed to be a helpful adjuvant treatment in MOE. According to our data, HBOT should be considered for patients who failed conventional treatments and in severe cases.

Keywords: Hyperbaric oxygen; Malignant otitis externa; Necrotizing otitis externa.