Covert bacteriuria of childhood. A clinical and epidemiological study.

A 4-year screening programme for covert bacteriuria in Dundee primary schoolgirl entrants showed a prevalence of 1·6% and an annual incidence of 0·9%. Among 109 children with bacteriuria, 70% had symptoms of lower urinary tract infection, 35% had vesicoureteric reflux, and 23% radiological evidence of pyelonephritis. Both pyuria and a past history of urinary infection were related to radiological evidence of reflux or pyelonephritis. Covert bacteriuria was found more frequently in children from social classes IV and V; and their housing, home circumstances, and home care were worse than a control group, even when allowance was made for their social class differences. The children appeared generally healthy but were smaller than a control group. The data suggest that the great majority of these children are not seriously at risk and that there is at present not sufficient evidence to warrant prescriptive screening.