Use of rapid dipstick tests to exclude urinary tract infection in children

Children presenting with symptoms attributable to urinary tract infection ( UTI) are not uncommonly referred to paediatric departments for assessment. The aim of this study was to evaluate the use of rapid dipstick tests in th e diagnosis of urinary tract infection in children. Urine was collected fro m 375 children admitted to a general paediatric ward, in whom UTI was a pos sibility on clinical grounds. Of these, 124 were less than one year old. Ur ine was tested with a dipstick for the presence of nitrite and leucocyte es terase. Bacterial culture and examination for white cells, red cells and ot her formed elements were performed. The results of the dipstick tests, micr oscopy and culture were correlated with the clinical details. Combination o f a negative dipstick test for nitrite and leucocyte esterase showed a nega tive predictive value for UTI of 96.9% and a specificity of 98.7%. In child ren less than a year old these values were 96.7% and 99.2% respectively. Th e leucocyte esterase strip test showed a negative predictive value for pyur ia of 94.3% with a specificity of 86.9%. In children less than a year old t hese values were 93.1% and 84.4% respectively. The use of dipsticks for the detection of urinary nitrate and leucocyte esterase in daily clinical prac tice is recommended. In children, the absence of both nitrite and leucocyte esterase in urine indicates that UTI is unlikely; however, positive dipsti ck tests for nitrite and/or leucocyte esterase are not specific indicators of UTI, and should not be used in place of laboratory examination. The dips tick method is most likely to be useful as a screening test to exclude UTI in children, but may be less suitable for infants. It should not be used to diagnose urinary tract infection.