Endocrine Abstracts

Introduction: Necrotizing external otitis (NEO) is a serious life-threatening infection of the external ear and skull base condition. The precise etiology of this condition is unknown. Diabetes mellitus is well known to be one of the most tightly associated characteristics seen in NEO patients. It is documented that diabetes causes endarteritis and microangiopathy, leading to poor microcirculation and impaired polymorphonuclear cell function.

Patients and methods: A retrospective chart review was performed in the ENT Department and neck surgery of Farhat Hached hospital Tunisia between 2000 and 2018. 94 patients with a diagnosis of NEO were identified in the medical records within this period.

Results: Seventy-seven patients were diabetic within the period of study, which represent 82% of cases. The average duration of diabetes follow up was 8 years. The mean age was of 67 years and the male:female ratio was of 43:33. Four patients had associated chronic renal failure. All patients have received oral and local antibiotics before hospitalization. Symptoms were made of otalgia in all patients, otorrhea in 48 patients. Headache and temporo-mandibular joint pain were reported in six cases. Fever was observed in three patients. Four patients noted ipsilateral facial palsy. Stenosis of external auditory canal was observed in all patients. On admission, the fasting blood sugars levels ranged between 1.8 and 4.8 g/l. The erythrocyte sedimentation rate ranged from 33 to 110 mm/h. Computed tomography confirmed the NEO in all cases. Pseudomonas aeruginosa was the most commonly isolated organism in 84% of cases. Patients have primary received intravenous anti-pseudomonal medications. Antifungual therapy was conducted in 16% of cases. Diabetic control worsened with the onset of invasive external otitis in all cases. One patient received hyperbaric oxygen therapy as adjuvant treatment. A regression of symptoms was observed in 88% of cases. Patients were discharged after a mean duration of hospitalization of 34 days.

Conclusion: Successful management of NEO frequently requires a multidisciplinary approach with treatment discussed with an endocrinologist, radiologist, and infectious disease specialist. Adequate control of diabetes, the correction of electrolyte imbalance must be instituted at the earliest opportunity in association with antibiotic therapy. A quick and proper diagnosis is needed to start treatment and reduce morbidity and mortality.