A comparitive study of griess nitrate test and urinary culture in detection of asymtomatic bacteriuria in children.

Abstract

Background: Screening of asymptomatic bacteriuria (ASB) in children is strongly recommended to detect and treat renal diseases like urinary tract infections, obstructive uropathy, reflux nephropathy, hereditary nephritis and End stage renal disease . Culture is the gold standard method to detect ASB but cannot be adopted everywhere as it is available in few major cities is time consuming and expensive. The objective of this study was to see the accuracy of Griess test as a screening test to detect nitrates reducing bacteria in urine. Method: In this study asmptomatic school children of both sexes aged between 5 to 14 yrs selected from schools of Mysore city. Urine was collected as midstream voided specimen and immediately transported to the laboratory, where the specimens were processed for Griess test and culture. The results were recorded and calculated for sensitivity and specificity of the test. Results: The specimen of 1000 cases were examined for bacteriuria with Griess test and also inoculated on media. There were 8 cases positive for bacteriuria with Griess test. Culture was positive in 25 cases and in the culture positive , 14 cases were found mixed growth (contaminants) and 11 cases were culture positive. sensitivity and specificity of griess test was 76.6% and 100% respectively. Conclusion: Although Griess test cannot be compensatory for culture it can be applied as a screening test due to good sensitivity and specificity in resorce constrain settings. It is easy to perform with instant results and to interpret without going special training for it.