Malignant External Otitis: What the Diabetes Specialist Should Know—A Narrative Review

AIMS: Malignant external otitis (MEO) is a special type of external otitis associated with extensive inflammation and osteomyelitis. It is believed to originate from the external auditory meatus and advance regionally to the soft tissues and the bone, eventually involving the skull base. Pseudomonas aeruginosa and diabetes mellitus are factors commonly involved in the pathogenesis of MEO. Although its treatment has changed considerably during the last decades, morbidity and mortality of the disease remain high. Our aim was to review basic aspects of MEO, a disease unknown until 1968, which attracts great interest among Ears, Nose and Throat (ENT), diabetes and infectious diseases specialists. METHODS AND RESULTS: In this narrative review we mainly include relevant papers written in English or with an English abstract. We searched PubMed and Google Scholar, using the keywords malignant external otitis, malignant otitis externa, necrotizing external otitis, skull base osteomyelitis, diabetes mellitus and surgery up to July 2022. Some of the most recent articles, with specific references to earlier articles and a book reference regarding the pathophysiology, diagnosis and treatment of MEO and its relationship to diabetes mellitus, were included. CONCLUSION: MEO is not an uncommon disease and is principally treated by ENT surgeons. Nevertheless, diabetes specialists should be aware of the disease presentation and management, since they will often encounter patients with undiagnosed MEO or will need to manage glucose levels in patients hospitalized with the disease.