Risk factors for nephrotoxicity in patients receiving outpatient continuous infusions of vancomycin in an Australian tertiary hospital

Objectives: To assess the risk factors for nephrotoxicity caused by vancomycin continuous infusion in a predominantly Caucasian outpatient population. Methods: This was a retrospective cohort study of 155 patient episodes from December 2006 to December 2011. Results: Vancomycin-associated nephrotoxicity (VN) occurred in 26 of 155 (17%) patient episodes. After adjustment for baseline renal function, maximum steady-state vancomycin concentrations >= 32 mg/L [OR 8.7 (95% CI 3.1-29.6), P < 0.001] and angiotensin receptor blockade [OR 9.78 (95% CI 3.1-39.4), P < 0.001] were independently associated with VN. The cumulative dose and duration of vancomycin therapy were not independent predictors of VN. Conclusions: Cessation of angiotensin receptor-blocking medications in selected patient groups, enhanced monitoring and establishing target steady-state concentrations <30 mg/L to avoid excessive vancomycin exposure may reduce the risk of VN.