The Utility of Real-Time Quantitative Polymerase Chain Reaction Genotype Detection in the Diagnosis of Urinary Tract Infections in Children

Abstract

Urinary tract infections (UTIs) are the most common serious bacterial infection in children with significant morbidity with delayed diagnosis. Polymerase chain reaction (PCR) is very accurate in detecting bacteria and widely available, but has never been evaluated to detect UTIs in children. To assess the utility of PCR as a rapid diagnostic tool, we conducted a prospective cohort study of 193 urine samples from children younger than 36 months undergoing evaluation for UTI in the emergency department over a 10-month period. A quantification cycle (Cq) threshold of 26.15 identified all Escherichia coli positive samples with sensitivity and specificity of 100% and 99.5%, respectively (95% CI = 71.5%-100% and 97.9%-99.5%, respectively). A Cq threshold of 19.03 identified E coli infections >100 000 colony forming units/mL with sensitivity and specificity of 100% (95% CI = 72.2%-100% and 98.6%-100%, respectively). PCR is very accurate in diagnosing E coli UTIs in young children and could be useful as a rapid diagnostic tool.

Diagnostic value of biomarkers for paediatric urinary tract infections in primary care: systematic review and meta-analysis

“…Bias was present for patient selection, caused by retrospective sampling ( n = 20) [ 16 , 19 , 24 , 34 – 36 , 38 , 43 , 50 , 52 , 53 , 69 , 71 , 74 , 76 , 81 , 82 , 86 , 88 , 90 ], convenience sampling ( n = 8) [ 21 , 37 , 39 , 41 , 46 , 51 , 61 , 65 ], or including a narrow spectrum of patients ( n = 4) [ 72 , 77 , 83 , 90 ]. All retrospective studies were considered at high risk for selection bias, because these studies might overestimate the diagnostic accuracy of the index test [ 26 ].…”

Clinical Features for the Diagnosis of Pediatric Urinary Tract Infections: Systematic Review and Meta-Analysis

“…The overall risk of bias was moderate to high. The high risk of selection bias was caused by retrospective sampling (n = 9), 16,24,25,33,44,45,47,51,52 recruiting a convenience or nonconsecutive sample (n = 5), 23,27,30,40,42 and including a narrow spectrum of patients (n = 4). 26,31,46,48 Studies were considered at high risk of bias for reference standard when the positivity threshold was not adapted to the sampling method (n = 5) 17,27,32,36,52 or was lower than the recommended threshold (n = 3).…”

“…The high risk of selection bias was caused by retrospective sampling (n = 9), 16,24,25,33,44,45,47,51,52 recruiting a convenience or nonconsecutive sample (n = 5), 23,27,30,40,42 and including a narrow spectrum of patients (n = 4). 26,31,46,48 Studies were considered at high risk of bias for reference standard when the positivity threshold was not adapted to the sampling method (n = 5) 17,27,32,36,52 or was lower than the recommended threshold (n = 3). 26,31,47 A high risk of bias for flow and timing was assumed when a urine sample was obtained from a small proportion of included children (n = 3) 41,43,53 or for inappropriate exclusions from the analyses (n = 2).…”

“…In 1 low-prevalence study, the LR+ was 6.27 (95% CI, 1.47-26.71), whereby hematuria might be considered a red flag. 15 Dysuria (LR+ 3.28; 95% CI, 2.22-4.86; n = 7) 4,15,26,28,33,35,46 and frequency (LR+ 2.21; 95% CI, 1.78-2.75; n = 4) 4,15,26,33 moderately increased the *References 16,17,[23][24][25]27,29,30,32,33,36,39,40,[42][43][44][45][46][47][49][50][51][52][53][15][16][17]24,25,[27][28][29][30][35][36][37]39,40,…”

A rapid microfluidic platform with real-time fluorescence detection system for molecular diagnosis

“…As the most advanced nucleic acid molecular diagnostic method in the world, qRT-PCR is widely used in clinical and biological researches. Furthermore, as a gold standard for molecular diagnosis, a strong consensus on its high sensitivity and good repeatability has been reached [4,5]. For example, in the past, hepatitis B virus (HBV), a highly infectious blood-borne agent related to liver, was just screened by the immunological screening technique.…”