In children with UTI, sensitivity of CRP (cut-off 20 mg/L) and PCT (cut-off 0.5 ng/mL) in predicting pyelonephritis is high (94% and 86%, respectively), but specificity varies (39% and 74%, respectively)).28 However, the number of studies in this systematic review was limited and the heterogeneity substantial. Here, CRP is linked to bacterial urinary tract infection.