A diagnosis-based scoring system to predict outcomes in necrotising otitis externa
Reviewed by Madhup K Chaurasia

Patients admitted with necrotising otitis externa have increased six-fold in the last 10 years. The prognosis is variable and dependent on co-existing morbidities. Charlston Comorbidity Index (CCI) is a weighted comorbidity scoring method, based on the presence or absence of 19 different comorbidities and, apart from predicting prognosis, measures relative risk of one-year mortality. The comorbidities list includes diabetes, cardiovascular conditions, immunosuppressive conditions, cranial nerve palsies, biological markers, microorganisms involved and radiological findings. CCI applied to patients with necrotising otitis externa also helps to predict secondary care visits by them in terms of healthcare utilisation. This is a retrospective study, comprising 26 patients admitted over two years with necrotising otitis extrna. Nineteen percent mortality was observed at one year. This was related to high Charlston Co-morbidity Index. Patients with a CCI of lower than five were younger, had lower HbA1c and were discharged earlier. Those with CCI of five or more (16 patients), fell into higher age group, had poor glycaemic control and stayed longer in the hospital. Mortality was associated with a CCI in excess of five and increased by 29% with every unit rise of CCI score. Other predictors of morbidity and mortality were cranial nerve palsies and infection or erosion beyond external auditory canal as observed by imaging. However, traditional variables do not necessarily categorise patients as low risk, and use of CCI score provides a validated tool in long-term patient counselling, management and expectation of prognosis.

Necrotising otitis externa – is a poor outcome predictable? The application of a diagnostics-based scoring system in patients with skull base osteomyelitis.
Rojoa DM, Raheman FJ, Sama Y, et al.
J LARYNGOL OTOL
2022;136:379-85.