Analysis of risk factors for bladder-ureteral reflux in children with urinary tract infection

Objective To explore the predictive factors for bladder-ureteral reflux (VUR) in children with urinary tract infection (UTI). Methods A total of 995 UTI children who were admitted to Department of Nephrology, Rheumatology, and Immunology, the Children's Hospital of Jiangnan University from October 2020 to November 2024 were enrolled. Their clinical data were collected for retrospective analysis. The children were stratified based on age (whether older than 2 years), and then divided into the VUR group and non-VUR group, according to the Results of micturating cystourethrography (MCU). Predictive factors for the occurrence of VUR in children with UTI in different age groups were identified. Receiver operating characteristic (ROC) curves were plotted and the area under the curve (AUC) was calculated. Results A total of 209 UTI children were included in the study. For UTI infants under 2 years of age, fever peak and red blood cell distribution width (RDW) were independent risk factors for the development of VUR. The ROC curve for the combined prediction of these two factors had an AUC of 0.774, a Youden index of 0.467, with sensitivity and specificity of 0.827 and 0.640, respectively. For UTI children aged 2 years and older, urine turbidity, RDW, abnormal radionuclide renal static imaging (DMSA), and abnormal urinary ultrasound were independent risk factors for the development of VUR. The ROC curve for the combined prediction of these four factors had an AUC of 0.865, a Youden index of 0.617, with sensitivity and specificity of 0.805 and 0.813, respectively. Conclusions For infants under 2 years of age, fever peak and elevated RDW; and for children aged 2 years and older with UTI, urine turbidity, elevated RDW, abnormal DMSA, and abnormal urinary system ultrasound, are all risk factors for the development of VUR. These findings are helpful for early identification and screening of VUR in clinical practice.