Malignant otitis externa: a review.

Malignant otitis externa is a rare but potentially fatal disease of the external auditory canal seen mostly among elderly, diabetic or immunocompramised patients. The causative organism is mainly Pseudomonas aeruginosa. The disease spreads rapidly, invading surrounding soft tissues, cartilage and bones causing their necrosis and even spreading to the cranial nerves. The disease can be fatal if treatment is not aggressive and timely, especially if it spreads outside the auditory canal with involvement of the cranial nerves. Treatment is mainly medical with antipseudomonal drugs like the third generation cephalosporin and the fluoroquinolones and local debridement. With aggressive treatment the mortality rate from this disease, which used to be 50% in the past has now been reduced to 10-20%. The pathophysiology of the disease, clinical presentation, diagnosis, treatment and the outcome has been discussed and reviewed.