Diagnostic Values of Immature Granulocytes Detected by the Sysmex XN 9000 Hematology Analyzer in Children with Urinary Tract Infections.

Immature granulocytes (IGs) are used as markers of infection and systemic inflammation. We aimed to investigate the diagnostic value of IGs in children with urinary tract infections (UTIs). Children with their first UTIs were included in this observational study. Blood samples were obtained before antibiotic therapy. The blood analysis was repeated 2 weeks after the treatment ended. In total, 194 children (95 with febrile UTI, 58 with cystitis, and 41 controls) were included. The percentage of IGs (IG%) and IG count (IGC) measured at the time of admission were higher in the patients with febrile UTI than in the patients with cystitis and the controls (P = 0.000). The IGC and IG% after treatment were higher in patients with renal scarring than in those without scarring (P = 0.012 and P = 0.021, respectively). Cox's regression analysis showed the significant associations of renal scarring with both IGC and IG% (hazard ratio: 8.181, P = 0.002; hazard ratio: 5.106, P = 0.033, respectively). Both IGC and IG% were positively associated with severe vesicoureteral reflux (VUR) [odds ratio (OR): 22.235, P = 0.025; OR: 15.597, P = 0.038, respectively]. In conclusion, the IG% and IGC, which can be easily measured in a routine complete blood count without the need for additional effort, could be used as biomarkers for predicting febrile UTI, renal scarring, and severe VUR in children.