Urine Interleukin-1β Can Be Used for Early Prediction of Urinary Tract Infection in Children

Abstract

Objective: Interleukin 1 beta (IL-1β) is an essential proinflammatory mediator emerging early in bacterial infection. Urinary tract infections (UTI) are one of the most common bacterial infections during childhood. This prospective study aimed to explore whether urine levels of IL-1β could be used as a biomarker of UTI. The study also aimed to define the optimal cut-off level for urine IL-1β to detect UTI in children. Material and Method: Sixty patients with symptomatic UTI and 29 healthy controls were registered in the study. After taking informed consent, urine culture, urinalysis, serum urea and creatinine, C-reactive protein (CRP) and serum white blood cell count measurements were performed in both groups. Urine IL-1β was analyzed by enzyme-linked immunosorbent assay. Results: The mean urine IL-1β level was significantly greater in the UTI group than in the controls (21.14 pg/ml vs 2.60 pg/ml, p=0.0001), and using a cut-off of 6.11 pg/ml for urine IL-1β for early prediction of UTI, sensitivity and specificity were 100% and 93.1%, respectively (AUC: 0.971). The mean urine IL-1β/creatinine ratio (uIL-1β /Cr) was also significantly greater in the UTI group (46.87 pg/mgCr vs 3.29 pg/mgCr; p=0.0001), and using a cut-off of 9.45 pg/mgCr for uIL-1β/Cr for early prediction of UTI, sensitivity, and specificity were 96.7% and 89.7%, respectively (AUC: 0.963). Conclusion: Both urine IL-1β and uIL-1β/Cr can be used as a sensitive biomarker for early prediction of UTI. Further research with larger groups is necessary to support our results.