Evaluation of Mean Platelet Volume Role in Prognosis of Spontaneous Bacterial Peritonitis

Abstract

Spontaneous bacterial peritonitis (SBP) (a complication of liver cirrhosis and ascites) is the infection of a previously sterile ascetic fluid without an apparent intra-abdominal source of infection. The diagnosis of spontaneous bacterial peritonitis (SBP) is based on a polymorph nuclear leukocytes (PMNs) exceeding 250/μL in ascetic fluid. The aim of the study was to evaluate MPV as diagnostic marker for detecting SBP and whether it could be used as prognostic factor to follow up response to treatment of SBP. A total of 198 patients with cirrhosis and ascites and 50 healthycontrolsubjectswere enrolled in this study. According to ascetic fluid analysis, they were divided into a SBP group including 100 patients, and a non-SBP group of 98 patients. All patients were subjected to full clinical assessment, laboratory test evaluation (Complete blood picture including Mean Platelet Volume, liver function tests, kidney function tests, coagulation profile, ascetic fluid analysis and ascetic fluid culture), Abdominal ultrasonography and calculation of Child Pugh score. Patients with SBP were treated and follow up MPV was done after five days. The ability of MPV values to predict SBP in cirrhotic patients was analyzed using receiver operator characteristic (ROC) curve analysis. Results revealed a statistically significant increase in MPV levels in cirrhotic patients with SBP compared to cirrhotic patients without SBP (p < 0.001) and healthy controls (p=0.05). A statistically significant increase was observed in the SBP group with respect to MPV, ESR and C-reactive protein (CRP). ROC curve analysis suggested that the optimum MPV level cut-off point for cirrhotic patients with SBP was 8.4 fl, with a sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of 73%, 85.7%, 75.7% and 83.9%, respectively (area under curve: 0.84), follow up patients with SBP after end of treatment showed statistically significant difference in MPV measured before 8.5±0.6 fl and after treatment 8.1±0.8 fl (P < 0.0001). We concluded that MPV is increased in cirrhotic patients with SBP. MPV measurement can be considered to be a rapid, easily applicable and valuable diagnostic tool of SBP in cirrhotic patients, Besides it can be used as a prognostic marker to follow up response to treatment.