Dr. Lindsay E. Nicolle, MD, FRCPC, Department of Internal Medicine and Medical Microbiology, University of Manitoba, Winnipeg, MB.
The prevalence of asymptomatic bacteriuria increases with advancing age in community populations, and approaches 50% in the functionally impaired, institutionalized elderly. Asymptomatic bacteriuria is usually associated with pyuria, but has not been shown to contribute to any short- or long-term negative clinical outcomes in the older population. Treatment of asymptomatic bacteriuria is not recommended. Clinical trials evaluating antimicrobial therapy have found no improved outcomes, and therapy is usually followed by recurrence of bacteriuria. Antimicrobial treatment also is associated with increasing antimicrobial resistance and adverse drug effects. Due to the high prevalence of positive urine cultures, bacteriuria is not a useful diagnostic test for symptomatic urinary tract infection. However, a negative urine culture may exclude the urinary tract as a potential source of infection.
Key words: urinary tract infection, bacteriuria, older adults, long-term care.