LOW BACTERIAL COUNTS IN INFANTS WITH URINARY-TRACT INFECTION

We analyzed the number of colony-forming units in urine cultures obtai ned by suprapubic aspiration in a group of 366 unselected infants with symptomatic urinary tract infection to relate these findings to facto rs such as pyuria and vesicoureteric reflux. Seventy-three (20%) of 36 6 infants had fewer than 100,000 colony-forming units per milliliter. Such low counts were significantly related to low numbers of leukocyte s in the urine. Vesicoureteric reflux was equally distributed among ch ildren, irrespective of the number of bacteria in quantitative culture . The findings emphasize the importance of sampling technique; in infa nts, the method of choice is suprapubic aspiration, or catheterization , which eliminates the risk that urinary tract infection is overlooked because of low bacterial counts.