Prevalence of asymptomatic bacteriuria and comparison between different screening methods for its detection in infants.

Urine was cultured from 441 healthy children, aged 3 to 36 months, simultaneously by standard pour plating and by dip-slide. Significant bacteriuria (greater than or equal to 10(5) colony-forming units/ml in two successive specimens) was found in 13 children (2.9%): 11 boys, 2 girls. Proteus mirabilis was the most frequently isolated organism. Of the 13 infants, 2 had malformations on intravenous pyelography. All 13 had a negative antibody-coated bacteria test. Nitrite test (N-Multistix) and microscopic examination were also performed. The results suggest that asymptomatic bacteriuria cannot be accurately predicted either by microscopic examination or by the nitrite test, and that the quantitative urine culture by dip-slide is the easiest and most reliable way of diagnosing urinary tract infections. However the criteria of Kass were found to be too strict.