Increasing antimicrobial resistance and the management of uncomplicated community- acquired urinary tract infections. Ann Intern Med 2001;135

Community-acquired urinary tract infections (UTIs) are among the most common bacterial infections in women. Therapy for these infections is usually begun before results of microbiological tests are known. Furthermore, in women with acute uncomplicated cystitis, empirical therapy without a pretherapy urine culture is often used. The rationale for this approach is based on the highly predictable spectrum of etiologic agents causing UTI and their antimicrobial resistance patterns. However, antimicrobial resis-tance among uropathogens causing community-acquired UTIs, both cystitis and pyelonephritis, is increasing. Most important has been the increasing resistance to trimethoprim–sulfamethoxazole (TMP–SMX), the current drug of choice for treatment of acute uncomplicated cystitis in women. What implications do these trends have for treatment of community-acquired UTIs? Preliminary data suggest that clinical cure rates may be lower among women with uncomplicated cys-titis treated with TMP–SMX when the infecting pathogen is resis-tant to TMP–SMX. Women with pyelonephritis also have less bacterial eradication and lower clinical cure rates when treated with TMP–SMX for an infection that is resistant to the drug. Therefore, in the outpatient setting, identifying risk factors for TMP–SMX resistance and knowing the prevalence of TMP–SMX resistance in the local community are important steps in choosing an appropriate therapeutic agent. When choosing a treatment regimen, physicians should consider such factors as in vitro sus-ceptibility, adverse effects, cost-effectiveness, and selection of re-sistant strains. Using a management strategy that takes these variables into account is essential for maintaining the safety and efficacy of treatment for acute UTI. Ann Intern Med. 2001;135:41-50. www.annals.or