Is the mean platelet volume a predictive marker for the diagnosis of acute pyelonephritis in children?

Acute pyelonephritis (APN) can lead to renal scar formation, high blood pressure, and end-stage renal failure. Prompt and early diagnosis of APN is important for preventing future complications. Our goal was to study the mean platelet volume (MPV) as a predictor of APN in children. The records of 43 patients with APN and 51 patients with a lower urinary tract infection (UTI) were investigated prospectively. APN was confirmed using radioactive nuclide 99mTc-DMSA scanning. The white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP), and MPV of both groups were measured and compared. The WBC count, MPV and ESR values, and the serum concentration of CRP were higher in the APN group than in the lower UTI group (p < 0.05). In the children with APN, the optimal cut-off value for the MPV was 8.2 fl [area under the curve (AUC): 0.906], with sensitivity of 81.4 % and specificity of 86.3 %. The MPV was associated with APN (p = 0.001), and the sensitivity and specificity of the MPV for the diagnosis of APN were higher than those of the other inflammation markers. MPV > 8.2 fl yielded an adjusted OR of 7.8 (95 % CI 3.3-18.4, p < 0.001) for APN. MPV > 8.2 fl was significantly associated with late renal scar formation (adjusted OR 5.7, 95 % CI 2.3-13.8, p < 0.001). The MPV is a fast and reliable measurement with considerable predictive value for the diagnosis of APN and renal scars, and its predictive capacity is better than that of CRP, ESR, and WBC values.