The Effect of Aminoglycoside Restriction on the Resistance Pattern and Mortality of Nosocomial Bacteremia Caused by Gram-Negative Bacilli

ABSTRACT

OBJECTIVE:To evaluate the effects of an aminoglycoside restriction policy on expenditures for aminoglycosides, antimicrobial resistance rates and clinical outcome of nosocomial bacteremia caused by Gram-negative bacilli (GNB). METHODS: Starting in February, 2002, a prior consultation with an infectious disease specialist for using aminoglycoside antibiotics over 5 days was required in a 930-bed university hospital. In retrospective analysis of medical records 7 months after initiation of the aminoglycoside restriction policy, sixty cases of clinically relevant nosocomial bacteremia caused by GNB were found. These bacteremic patients were compared with sixty, species-matched, control patients with nosocomial Gram- negative bacteremia before the policy for total expenditures for aminoglycosides, susceptibility to antibiotics and clinical outcomes of bacteremia. RESULTS: During the same period of 7 months before and after the restriction policy, total expenditures for aminoglycosides decreased by 44% in cost (from 465,030,841 Won to 259,618,337 Won) and the antimicrobial utilization density of aminoglycosides decreased by 42% (from 225.2 to 130.3). On the other hand, the patterns of antibiotic susceptibility and bacteremia-related in-hospital mortality rates after the policy did not show a significant change, compared with those before the policy. CONCLUSION: Antibiotic restrictions are among the most popular methods to diminish the practice of antibiotic overuse in hospitals. In this study, requirement for prior approval of aminoglycoside use over 5 days led to a significant decrease in the amount and cost of total aminoglycosides without a significant change in susceptibility patterns and bacteremia-related mortality rates.