[Urinary antimicrobial prophylaxis].

Antibiotics are usually used to prevent childhood recurrent urinary tract infections: cystitis or pyelonephritis. The mechanism of action of these antibiotics, although imperfectly known, seems to be double: the antibiotic acts by its bactericidal effect, but also probably for minimal concentrations by reducing adhesion capability of bacteria to the urothelium. The most commonly used molecules are cotrimoxazole, trimethoprime, pivmecillinam, cefaclor and nalidixic acid. However all have not been studied rigorously as for their prophylactic capacity, and in particular very little is known for patients presenting with vesico-ureteral reflux.