Overtreatment of enterococcal bacteriuria

Abstract

Background: The purposes of this study were to investigate the clinical outcomes of enterococcal bacteriuria and to determine whether current management is adherent to Infectious Diseases Society of America guidelines.

Methods: We conducted a retrospective medical record review of patients from 2 academic teaching hospitals for 3 months (September 1 through November 30, 2009). Patients were classified as having urinary tract infection (UTI) or asymptomatic bacteriuria (ABU) by applying the guidelines. Antibiotic use was deemed appropriate in patients with UTI and inappropriate in ABU. Medical records were reviewed for Enterococcus cultured from another sterile site within 30 days.

Results: A total of 375 urine cultures growing Enterococcus were reviewed, with 339 cultures meeting inclusion criteria. Of these 339 episodes, 183 (54.0%) were classified as ABU and 156 (46.0%) as UTI. In 289 episodes accompanied by urinalysis, pyuria was associated with UTI in 98 of 140 episodes (70.0%) compared with 63 of 149 episodes of ABU (42.3%) (odds ratio, 3.19; 95% CI, 1.96-5.18). Providers inappropriately treated 60 of 183 episodes of ABU (32.8%) with antibiotics. In multivariate analysis, only pyuria was associated with the inappropriate use of antibiotics (odds ratio, 3.27; 95% CI, 1.49-7.18). Only 7 subsequent infections with Enterococcus occurred in the 339 episodes of bacteriuria overall (2.1%), with 2 of the 183 cases of ABU (1.1%) having distant infection.

Conclusions: Providers often overtreat enterococcal ABU with antibiotics, particularly in patients with pyuria. Given the low incidence of infectious complications, efforts should be made to optimize the use of antibiotics in enterococcal bacteriuria.