Malignant otitis externa--a high index of suspicion is still needed for diagnosis.

Malignant otitis externa is a destructive inflammatory process of the petrous temporal bone which if untreated leads to osteomyelitis of the skull base and can be fatal. It is more common in immunocompromised and elderly insulin-dependant diabetic patients and is caused by infection with Pseudomonas species. Despite a range of laboratory and radiological tests it still remains difficult to diagnose, particularly in the early stages when it can be treated medically. We describe three cases which presented to this department in the past twelve months. In all cases the diagnosis was made clinically and confirmed per-operatively. Interestingly all three cases were relatively young patients who did not have an immunocompromised status and were not diabetic.