Antibiotic Prophylaxis for Pediatric Urinary Infections

According to recent trials, the use of antibiotics after a pediatric urinary infection doesn’t reduce relapses, but the matter is still under discussion. Some researchers in Australia have performed a multicentric trial randomizing 576 children (average age 14 months; 64 of them were females), with an anamnesis of urinary infection shown through uroculture, to receive a prophylaxis with a low-dose antibiotic (2 mg/kg of trimetoprim plus 10 mg/kg of sulfamethoxazole) or with placebo, for 12 months. During follow-up, children treated with antibiotic have presented less infectious recurrences with a statistically significant difference (13% vs. 19%; p=0.02). Most relapses have occurred in the 6 months following the beginning of the trial. The results of performed imaging tests presented no differences between the treated group and the control group. Prophylaxis seemed more effective in the prevention of urinary infections in children with III-IV-stage vesical-urethral reflux (difference in the absolute risk: 6.8%) than in children with I-II-stage reflux (5.4%) and in children with no reflux at all (1.8%).

The trial is well performed and the sample is sufficient; unfortunately, the primary outcome has been set as number of relapses rather than as the evaluation of long-term renal function, which, from a clinical point of view, has a far greater importance. In any case, it is fundamental to diagnose the presence and the severity of a possible vesical-urethral reflux, since the real modifiable risk factor is this condition. In children not presenting a reflux of great importance, antibiotic prophylaxis of relapses is not indicated; for the ones with III-stage or higher reflux, the matter is still debated.