[Laboratory parameters as a guide for the radiologic study of infections of the urinary tract in childhood].

Forty-nine children with urinary tract infection aged between 15 days and 10 years were studied. Thirty-three of them (67.3%) had urinary tract malformations. We valued the following parameters: a) White Blood Cells; b) Leukocyte differential; c) ESR at the first hour; d) CRP; e) Concentration ability; f) Body temperature. We wanted to investigate the usefulness of these parameters to predict which patients should be studied by X-ray of urinary tract. Single parameters did not prove very sensitive; the highest correlations were found with ESR and CRP, which were positive in 76% of the cases of malformations. Furthermore we valued the sensitivity and specificity of the tests grouped together: the highest values of sensitivity (97%) and specificity (31%) were obtained coupling the ESR and concentration ability.