Diagnostic accuracy of urine routine examination for diagnosis of urinary tract infection in different pediatric age groups taking culture as gold standard: a single center study from Peshawar

Abstract

Introduction: The Urine Routine Examination (Urine RE) is used as the first step for diagnosis of urinary tract infections (UTI), even though it is not a definitive test for infection. This may result in anomalous administration of therapy for UTI in false positive cases as well as missed therapy in false negative cases.

Objective: To determine the sensitivity and specificity of urine routine examination in diagnosing urinary tract infection by taking urine culture as gold standard in pediatric age group in a tertiary care hospital.

Materials & Methods: A cross-sectional study was conducted in the department of Paediatrics, Rehman Medical Institute, Peshawar in March 2021. Retrospective data of last five years (2016-2020) were retrieved from patient medical records for demographics, clinical examination, and laboratory tests, and recorded on a purposefully designed Performa. Sensitivities, specificities, positive and negative predictive values, and positive and negative likelihood ratios were calculated for urine samples with 95% CI. All analyses were done at an alpha value of 0.05.

Results: A total of 368 children were included in this study, in which 144(39.1%) were male and 224(60.9%) were female.  Out of 368, 184(50%) had positive urine culture; out of 184 positive urine C/S, majority (107) were positive for E-Coli, followed by enterococcus species (25), and klebsiella (23). Sensitivity, specificity, PPV and NPV of WBC vs C/S was 67.39%, 74.46%, 16.56% and 96.8% respectively considering culture as gold standard. Similarly for nitrites it was 19.02%, 90.76%, 13.41% and 93.7%.

Conclusion: Traditionally Urine Routine examination is being used as screening tool for Urinary tract infection. However in our study low sensitivity among all pediatric age groups questions its effectivity as screening tool. This emphasizes the value of urine culture as screening investigation rather than urine RE.