Malignant Otitis Externa: An Experience of A 27-Year Period

Background and Objective: Malignant otitis externa is a rare but potentially fatal infection. It tends to affect the elderly as well as patients with diabetes and immunocompromised status. We aimed to identify the epidemiological, clinical, therapeutic, and evolutionary features of malignant otitis externa. Methods: We conducted a retrospective study including patients hospitalized in the infectious diseases department in Sfax (South of Tunisia) for malignant otitis externa between 1994 and 2020. Non-documented cases were excluded from the study at enrolment. Results: We encountered 82 patients, among whom 45 were male (54.9%). The mean age was 62 ±14 years. Seventy-four patients had diabetes mellitus (90.2%). The most common clinical symptoms were otalgia (86.5%) and otorrhea (69.5%). Pseudomonas aeruginosa was the most common organism (56%). The first-line antimicrobial used on admission was a combination of ciprofloxacin (65.8%) and ceftazidime (51.2%). The median duration of treatment was 6 weeks [4-32 weeks]. The disease evolution was favorable in 67 cases (81.8%). According to the length of hospital stay, patients hospitalized for ≥ 21 days consulted after significantly longer duration of complaints (49 days vs. 36 days; P=0.01) and had significantly more frequent complications (35.3% vs. 10.4%; P<0.001), while the recovery was significantly more frequent in patients hospitalized less than 21 days (89.6% vs. 70.6%; P=0.02). Conclusion: Despite advancements in treatment and the variability of imaging modalities, malignant otitis externa remains a fatal disease. The diagnostic delay may worsen the disease outcome, requiring a longer duration of treatment and referral to surgery.