The predictability of mean platelet volume as a biomarker of pyelonephritis among pediatrics with urinary tract infection

Introduction: Delayed diagnosis of acute pyelonephritis and its differentiation from cystitis can lead to irreversible complications in renal tissue, hypertension and even renal failure. Objectives: The present study aimed to evaluate the diagnostic value of platelet volume in acute pyelonephritis. Patients and Methods: This cross-sectional study was conducted on 110 children with febrile acute urinary tract infection (UTI) referred to our educational hospital in Qom, Iran. Individuals with inclusion criteria were examined for mean platelet volume (MPV), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cell (WBC) and platelet counts. Additionally, Tc 99m-dimercaptosuccinic acid scan (DMSA scan) was used as the gold standard for differentiation of cystitis from acute pyelonephritis. Urine culture was also used to confirm diagnosis of UTI. Results: The mean age of the participants was two years with a range of two months to 13 years. The MPV (P=0.001), CRP (P=0.001), ESR (P=0.001), platelet (P=0.013) and WBC count (P=0.001) were significantly higher in the pyelonephritis group compared to cystitis group. We showed that MPV has similar potency in differentiating pyelonephritis from cystitis compared to other inflammatory markers; however CRP was more accurate than other markers. The cut-off point for MPV was estimated 7.8 fl, with sensitivity of 91%, specificity of 92.7%, and positive predictive value of 92.6%. Conclusion: The high level of ESR is a risk factor to develop pyelonephritis. MPV as an inflammatory marker is similar to that of other inflammatory markers in segregating pyelonephritis in children, although further studies are needed to confirm the results of this study.