بررسي قدرت تشخيصي آزمايش تجزيه ي ادرار در عفونت هاي ادراري كودكان

Diagnostic value of urine analysis for detection of urinary tract infection in children

Background Urinary tract infection (UTI) is one of the most important bacterial diseases among children and itʹs early detection has an important role in preventing secondary complications. The gold standard for diagnosis of UTI is urine culture, however, there are some arguments about the value of urine analysis as a screening test. This study was designed to evaluate specificity and sensitivity of urine analysis in patients suspicious to UTI in Shahid Fahmideh and Razi Hospitals during 1999-2000 in Kermanshah. Materials and Methods: This descriptive study was conducted on patients suspicious to UTI Who were not taken any antibiotic during the last 72 hours. Mid-stream urine samples were taken and the existence of leuckucyte or bacteria were examined by microscope. Blood, nitrite and protein were checked by Behring (Gremany) dipstick and urine culture were done for all samples. Positive criteria for diagnosis of UTI were positive culture with more than 105 colony count, existence of protein more than 1+, blood more than 1+ and more than 5 leukocytes in one microscopic field, positive nitrite test and any bacteria seen in one high power field of microscope. Results: Two hundred and twenty one patients including 163 girls and 58 boys were studied. Urine cultures were positive in 69.6%. Sensitivity and specificity were 86.3% and 73% for leukocyte, 66% and 84.3% for nitrite, 56.9% and 35.2% for protein, 61% and 44% for blood and 71.9% and 71.8% for bacteriuria, respectively. The existence of leukocyte in urine analysis had a sensitivity of 86.3% and positive nitrite test had a specificity of 84.3% for the diagnosis of UTI. Conclusion: In this study, the existence of leukocyte in urine analysis had the best sensitivity and positive nitrite test had the best specificity for the diagnosis of UTI. Therefore, dipstick is not a reliable screening test for the diagnosis of UTI.