Evolving Resistant Pseudomonas to Ciprofloxacin in Malignant Otitis Externa

Objective To determine whether there has been an increase in ciprofloxacin-resistant pseudomonas malignant otitis externa, and if this has increased the morbidity of the disease.

Study Design Retrospective.

Setting Tertiary referral center.

Patients Twenty-eight patients over 13 years.

Results The records of a total of 28 patients who were admitted between 1988 and 2001 with the diagnosis of malignant otitis externa were reviewed. Seven patients had ciprofloxacin-resistant pseudomonas on their hospital culture and sensitivity test. Five of the 7 resistant cases appeared in the last 3 years, as opposed to 2 of the 7 who appeared in the 10 years before that period. In our series, there is a significant trend developing over time of pseudomonas resistant to treatment with ciprofloxacin. No increased morbidity or mortality was found in the ciprofloxacin-resistant pseudomonas group compared with the remaining patients who were sensitive to ciprofloxacin.

Conclusions In our series, resistance to ciprofloxacin in patients with malignant otitis externa is increasing over time. This may have an impact on the relatively successful outpatient treatment of these patients in the past decade. A return to inpatient or outpatient intravenous treatment with third-generation cephalosporins/antipseudomonal penicillins and more frequent debridement will be required in these patients.