Immunosuppression, infection, and epidermal compromise: an aetiological triad for necrotising otitis externa that highlights potential modifiable risk factors

Abstract

Objective A key clinical feature of necrotising otitis externa is granulation tissue arising from the ear canal, representing epidermal compromise. The aim of this work was to explore the role of epidermal compromise in the aetiology of necrotising otitis externa. Method A structured risk factor history was taken from 54 patients diagnosed with necrotising otitis externa between 2017 and 2022. Primary care records were also reviewed. Results A total of 94 per cent of patients reported incidents of potential epidermal compromise preceding severe pain onset, including a 35 per cent incidence of ear syringing. A total of 94 per cent of patients were immunosuppressed, including 78 per cent with diabetes. All patients had medical co-morbidities. Conclusion This study proposed an aetiological triad for necrotising otitis externa: immunosuppression, infection and epidermal compromise. Epidermal compromise is a potentially modifiable risk factor for necrotising otitis externa. Meticulous primary ear care for older adult, diabetic and immunosuppressed patients is recommended. These populations should never undergo ear syringing and should avoid ear canal trauma and prolonged exposure to moisture.

A systematic review of antimicrobial treatment regimens and their outcomes in necrotising otitis externa

“…Necrotising otitis externa patients tend to be frail, immunosuppressed, and have medical co-morbidities. 1 Necrotising otitis externa patients also tend to receive prolonged parenteral antimicrobial treatment. It is therefore unsurprising that 95 per cent of studies in this review involved delivery of at least initial courses of treatment in an in-patient setting.…”

“…Necrotising otitis externa is a serious infective condition originating from the external auditory canal, largely but not exclusively in patients with recognised risk factors. 1 The first report of necrotising otitis externa appears in the literature in 1830, 2 with the first case series described by Chandler in 1968. 3 Necrotising otitis externa has a profound effect on patients' quality of life 4 and carries potentially fatal complications.…”

Necrotising otitis externa, epistaxis first aid advice, laterality in otolaryngology and what medical students want from ENT teaching

“…Previous recent papers set the scene for this publication. [2][3][4] The take home message is that for such an important condition, the heterogeneity of reporting of cases requires improvement if progress is to be made in managing this treacherous condition. Important questions such as optimal drug combinations, optimal duration of treatment and the spread between mortality from NOE itself, from treatment adverse effects or from co-morbidities need answers and there is little or no clarity at present.…”