Predictors of Spontaneous Bacterial Peritonitis Among Patients with Cirrhosis

Prevalence of spontaneous bacterial peritonitis (SBP) varies from approximately 4% among asymptomatic patients to 30% among those hospitalized [1, 2].Previous studies explored the role of several biomarkers, such as tumor necrosis factor-α, procalcitonin, and fecal calprotectin, for prediction of SBP The NLR is speculated to reflect immune regulatory mechanism (lymphocytes) and ongoing inflammation (neutrophils) . Assessing the diagnostic value of NLR for liver disease has gained particular interest, namely, among patients with nonalcoholic fatty liver disease and hepatocellular carcinoma . Direct interaction between platelets and bacteria lead to platelet activation . Platelet activation leads to change of platelet shape with increase in platelet size and anisocytosis, and consequent increase in both mean platelet volume (MPV) and platelet distribution width (PDW) .Acute phase reactants, such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), are elevated among patients with SBP, as a result of cytokine synthesis . Older patients, due to higher possibility of advanced liver disease and more frequent comorbidity, are more susceptible to SBP .

The Department of Tropical Medicine (Mansoura University) developed a simple scoring system for prediction of SBP among cirrhotic patients with ascites, which include four variables: age, MPV, NLR, and C-reactive protein (CRP) . The independent predictors of SBP were age of at least 55 years, MPV of at least 8.5 fL, NLR of at least 2.5, and CRP of at least 40 mg/dL . The progression of hospitalized patients with SBP can lead to an in-hospital mortality rate of approximately 17% .

Therefore, the sequelae of SBP highlight the increasing value of establishing reliable diagnostic biomarkers. The earlier the diagnosis, the lower the mortality rate.To our knowledge, only one, national study utilized MPV, NLR, and CRP for prediction of SBP among cirrhotic patients with ascites [3].We intend to further extend both the diagnostic utilities (by adding ESR to the previously mentioned tools) and the spectrum of prediction, to include mortality in addition to the development of SBP among cirrhotic patients with ascites.

The study aims at developing a local scoring system (RSS) for the prediction of SBP and its related mortality among cirrhotic patients with ascites admitted to Al-Rajhy Liver Hospital (Assiut University).

Our objective is to compare age, NLR, MPV, PDW, and CRP between cirrhotic patients with ascites complicated with SBP and those without SBP, and between surviving SBP patients compared to those with in-hospital mortality.