Urinary tract infection (UTI) is a common problem in children. Because clinical findings and commonly used blood indices are nonspecific, the distinction between lower and upper urinary tract infection cannot be made easily in this population. However, this distinction is important because renal infection can induce parenchymal scarring. The objective of this study was to determine the accuracy of procalcitonin (PCT) compared with C-reactive protein (CRP) rapid tests to predict renal involvement in children with febrile UTI.