Vancomycin Ototoxicity May Lead to Bilateral Vestibular Hypofunction (P1.9-015)

Objective: To report two cases of bilateral vestibular hypofunction, followling vancomycin use during hospitalization. Background: Bilateral vestibular hypofunction (BVH) is a chronic condition that affects about 28 people per 100,000. It is characterized by a bilateral reduction or loss of function of the vestibular organs and/or the vestibular nerves. Symptoms of BVH include oscillopsia, imbalance, and frequent falls. Recent case studies have reported on potential ototoxic side effects of vancomycin. Vancomycin, which is a commonly used antibiotic in the inpatient setting, is used to fight off drug resistant strains of bacteria such as Staphlococcus aureus (MRSA). These case studies examined the relationship of vancomycin use and the onset of BVH. Design/Methods: Case 1: A 62-year-old Caucasian male presented with severe imbalance that required him to start using a walker after three months of hospitalization. Previously, he had not experienced any balance issues. The patient was admitted for an infection in his peritoneal dialysis catheter and received IV vancomycin for two weeks. Both caloric testing and rotary chair confirmed the diagnosis of BVH. Case 2: An 87-year old Caucasian male initially came to Dent Neurologic Institute for seizures disorder with good balance. He was hospitalized for pneumonia and was sent home with oral vancomycin. After he began treatment with oral vancomycin (100mg TID) for two weeks, he started to experience imbalance and falls. Caloric testing and rotary chair confirmed BVH. Results: N/A Conclusions: These cases may suggest that vancomycin may be ototoxic and can lead to BVH. Vancomycin use has been on the rise during the past two decades and there has been an increase in dosage, which could be a contributing factor to these emerging cases of BVH. Discussing this specific side effect may be warranted before initiating patients with vancomycin treatment. Disclosure: Dr. Zak has nothing to disclose. Dr. Cox has nothing to disclose. Dr. Zhang has nothing to disclose.