Successful treatment of multi-drug resistant Pseudomonas aeruginosa, causing bilateral malignant otitis externa, media and mastoiditis

Abstract

Background: Malignant external otitis (MEO) is a relatively uncommon infection caused by Pseudomonas aeruginosa seen primarily in immunocompromised patients, classically, diabetics. MEO is treated effectively with antibiotics but can be associated with significant morbidity including cranial nerve palsies. Objective: To report a case of MEO seen in a patient with myelodysplastic syndrome and prolonged neutropenia whose infection was resistant to all of the commonly used antibiotics, including fluoroquinolones, third generation cephalosporins, aminoglycosides, aztreonam, imipenem, and extended spectrum penicillins. Although there have been reports of ciprofloxacin resistant P. aeruginosa causing MEO infections, we were unable to locate any cases in the literature resistant to both ciprofloxacin and third generation cephalosporins. Method: To treat our patient’s MEO, we employed colistin, an antibiotic seldom used since the early 1980’s due to its nephrotoxicity. Results: The infection responded well to colistin, and with intermittent dosing, the patient did not suffer from deterioration of renal function and colistin resistance did not develop. Unfortunately, the case was also complicated by bilateral facial palsy and long-term bilateral hearing loss, two complications, which although common in this disease, are rarely seen in a bilateral fashion.