Diagnostic Performance Of Reagent Strips And Microscopy For The Diagnosis Of Urinary Tract Infection Among Pregnant Women At the University Of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia A Cross Sectional Study

Abstract

Background: Pregnant women are susceptible to urinary tract infections due to changes in their urinary tract because the uterus lies directly on top of the bladder. The prediction of how to screen pregnant women for bacteriuriais a balance between the cost of screening sensitivity and specificity. The aim of this study was to evaluate the diagnostic accuracy of rapid dipstick tests and microscopy to predict UTI in pregnancy by comparing urine culture as a gold standard.

Method: A hospital based comparative study was conducted from March-April 2015 at Gondar University referral hospital. About 10-15ml of freshly voided midstream urine samples were collected from each participant. All samples were processed for urine dipstick tests, microscopic examination and cultured on CLED and identified by the conventional biochemical tests at the University of Gondar comprehensive specialized referral hospital Microbiology laboratory. Data was summarized and analyzed using SPSS version 20statistical software. The sensitivity, specificity, positive predictive and negative predictive and Kappa values were calculated to measure the diagnostic utility of urine diagnostic tests in the detection of UTI in pregnant women.

Result: A total of 282 pregnant women of whom11.7% (33/282) had ≥10⁵colonies/ml on culture; sensitivity, specificity, positive and negative predictive values were 39.39% ,73.38%,16.45% and 90.10% for leukocyte esterase, respectively, and 18.18% ,96.77% ,42.86% and 89.90% for nitrite were included. Moreover, sensitivity, specificity, PPV and NPV of bacterial microscopy were 36.36%, 78.25%, 18.20% and 90.30%, respectively.

Conclusion: This study revealed many false positive and negative results of urine dipstick and microscopy when compared with the gold standard culture method. The low sensitivity and positive predictive values of urine dipstick and microscopy tests proved that culture should be used for the diagnosis of urinary tract infections.