Urinary tract infections in obstetrics and gynecology.

Escherichia coli is still the most common bacterial pathogen associated with urinary tract infections in women. Because of increasing resistance, ampicillin or a sulfonamide alone is no longer recommended for the empiric treatment of those infections. Antimicrobial therapy that contains a beta-lactamase inhibitor or that is resistant to the action of beta-lactamase is preferred. For the treatment of acute, uncomplicated lower urinary tract infection in a young woman, a short course of therapy (single dose) may be adequate. For an upper tract or complicated infection a longer course of therapy is advised. Asymptomatic bacteriuria in pregnancy should be treated; a short course of therapy with a beta-lactam antibiotic may be tried only if posttherapy follow-up cultures are planned. When bacteriuria persists or recurs, a longer course of therapy should follow, with consideration given to a urologic workup after delivery.