Malignant Otitis Externa: A Novel Stratification Protocol for Predicting Treatment Outcomes.

OBJECTIVES: 1) Stratify malignant otitis externa into severe and nonsevere disease categories. 2) Predict treatment courses and outcomes based on this stratification.

SETTING: Tertiary center.

PATIENTS: Retrospective review 2004 to 2014; 28 patients. Inclusion criteria are a diagnosis by senior authors, radiographic evidence of disease, admission for intravenous antibiotics/debridement, minimum 1 year of follow-up.

INTERVENTIONS: Severe group stratification if two or more of the following: cranial nerve VII palsy, fungal positive culture, relapse, surgery performed, major radiographic findings. All other patients stratified to nonsevere group.

MAIN OUTCOME MEASURES: Cure, alive/refractory disease, death by disease, death by other cause. Secondary measures are antibiotic duration and number of disease-related admissions.

RESULTS: Forty-three percent (12 of 28) and 57% (16 of 28) of patients stratified into the severe and nonsevere groups. The severe group had significantly more adverse disease-specific outcomes than the nonsevere group (7 of 12 versus 0 of 16; p = 0.002). Disease-specific mortality was 42% and 0% in the severe and nonsevere groups, respectively. The severe group had longer antibiotic courses (12.8 versus 6.9 wk; p = 0.01) and more disease-related admissions/relapses (1.6 versus 1, p < 0.001). Only four of 12 severe group patients achieved cure. All but two nonsevere patients achieved cure, with those two dying of other causes.

CONCLUSION: A subgroup of malignant otitis externa may exist that is not as susceptible to parenteral antibiotics and local debridement. A combination of clinical and radiographic findings may be useful for stratifying patients into severe/nonsevere categories. Patients with severe disease may be more likely to die of their disease and have worse treatment courses such that additional surgical intervention may be indicated.