Diagnostic Accuracy of Mean Platelet Volume in Cirrhotic Patients with Spontaneous Bacterial Peritonitis Presented to the Emergency Department

Background: The aim of this study was to investigate the diagnostic accuracy of mean platelet volume (MPV) in predicting SBP in cirrhotic patients. Methods: This was an observational, analytical, and retrospective study conducted on cirrhotic patients with abdominal ascites referred to the emergency department (ED) over a 1-year period. The cirrhotic patients with ascites were divided into two groups with or without SBP. The diagnostic accuracy of MPV for detecting SBP was measured and compared with the analysis of the ascites fluid obtained by paracentesis as a gold standard procedure in the absence of any secondary causes of peritonitis. The required data were documented in a checklist. Results: A total of 252 patients, 126 with SBP and 126 without SBP, were included in the study. The mean MPV in these patients was 8.36 ± 0.92 fL. Patients with SBP had a significantly longer duration of cirrhosis, more severe fever and abdominal pain, and higher ascites WBC and PMN counts and higher mean MPV (p<001). At the most appropriate cut-off point (i.e., 8.3 fL), MPV provided the sensitivity, specificity, positive predictive value, negative predictive value, and the diagnostic accuracy of 69.84%, 53.97%, 60.27%, 64.15%, and 61.90%, respectively, for the diagnosis of SBP. The receiver operating characteristic (ROC) curve showed that MPV had an acceptable diagnostic accuracy (AUC = 0.677). Conclusion: Mean platelet volume, as a non-invasive, simple, and accessible laboratory parameter, with acceptable diagnostic accuracy in cirrhotic patients with ascites may have a predictive role in the diagnosis of SBP.