Uncomplicated urinary tract infections.

Background: Urinary tract infections (UTIs) are among the most common types of bacterial infection in outpatient medicine. Rising rates of antibiotic resistance and a better understanding of the ecological adverse effects (collateral damage) of antibiotics warrant a reevaluation of the treatment recommendations for uncomplicated UTI. The new S3 guideline contains updated recommendations.

Methods: The new S3 guideline is based on a review of publications on uncomplicated UTI retrieved by a systematic search of the Medline and Cochrane Library databases. Guidelines from abroad were also considered in the review.

Results: Uncomplicated UTI is classified as either uncomplicated cystitis (UC) or uncomplicated pyelonephritis (UP). The choice of a suitable antibiotic is determined by the following main criteria: the patient's individual risk profile and prior antibiotic treatment, if any; the spectrum of pathogens and antibiotic susceptibility; the proven efficacy of the antibiotic; the ecological adverse effects (collateral damage) of antimicrobial therapy; the side effects for the patient under treatment. On the basis of these criteria, co-trimoxazole/trimethoprim and fluoroquinolones can no longer be recommended as first-line empirical treatment for UC. Rather, the new recommended treatment of first choice consists of fosfomycin-trometamol, nitrofurantoin, or pivmecillinam. High-dose fluoroquinolones are still recommended, however, as first-line oral treatment for UP. Asymptomatic bacteriuria should only be treated in exceptional situations such as pregnancy or before urological procedures that will probably injure the mucosa of the urinary tract.

Conclusion: The new S3 guideline on uncomplicated UTI incorporates a forward-looking approach to the use of antibiotics in treating this common type of infection. It is intended to bring about a sustained improvement in the quality of care.