[Treatment of urinary tract infections].

Urinary tract infection (UTI) is common in pediatric age groups and may cause permanent renal damage. Because UTI may occur as the first manifestation of urinary tract malformation, evaluation, of urinary tract morphology should be routine. Variables influencing selection of the most appropriate therapy include the causative organism, location of the infection to the distal and/or proximal urinary tract, severity of constitutional symptoms, age, and history for prior urologic disease. Treatment of pyelonephritis requires bactericidal antimicrobial agents capable of achieving rapid sterilization of the renal parenchyma. Animal experiments have shown that the most effective agents are third-generation cephalosporins and aminoglycosides. Antibiotics are selected on the basis of age and severity of infectious symptoms. In infants under 18 months of age and in patients with severe constitutional symptoms, parenteral administration of both a third-generation cephalosporin and an aminoglycoside is recommended. Patients above 18 months of age who are not severely ill can be given a single oral drug, e.g., a cephalosporin, amoxicillin with clavulanic acid, or cotrimoxazole. Therapy should be continued for ten days in patients with infection of the proximal urinary tract, whereas 5 to 7 days are adequate in patients with cystitis and normal urinary tract morphology.