Importance of ascite PRO-BNP and cholesterol in differential diagnosis of portal hypertension

Introduction and Aim: Pathological fluid accumulation in the peritoneal cavity is defined as ascites. It can be seen in portal hypertension as well as non-portal causes. Serum – ascites albumin gradient (SAAG) is the most common used formula to differentiate these two groups. SAAG ≥ 1.1 mg/dL indicates portal hypertension and <1.1 mg/dL indicates non-portal hypertension. Congestive heart failure and vascular pathologies can cause portal hypertensive ascites even before cirrhosis occurs. Congestive heart failure can also lead to cirrhosis. In this study, we aimed to investigate the importance of ascites cholesterol and pro-BNP levels in predicting ascites etiology and the presence of cirrhosis. Patients and Method: One hundred fourteen patients with ascites followed in Istanbul University Faculty of Medicine Department of Gastroenterology between years 2017- 2020 were included in this study. Clinical findings, biochemical values, liver biopsies and radiological findings were used to diagnosed cirrhosis. Patients' demographic characteristics, laboratory findings, pro-BNP, ascites analysis (glucose, total protein, albumin, LDH, cholesterol, triglyceride, pro-BNP) were evaluated. Patients were grouped according to SAAG (as ≥ 1.1 mg/dL and <1.1 g/dL) and the presence of cirrhosis and were compared accordingly. Results: Of these 114 patients, 53.5% (61) were male, 46.5% were female and 62.2% (71) were cirrhotic and 37.8% (43) were non-cirrhotic. Mean serum - ascites albumin gradient was 2.0 ± 0.6 g/dL in cirrhotic patients and 1.5 ± 0.7 g/dL in non-cirrhotic patients (p=0.000). Mean ascites cholesterol was 27.0 ± 24.3 mg/dL in cirrhotic and 60.0 ± 31.8mg/dL in non-cirrhotic (p=0.000). Ascites cholesterol cut off point 50 mg/dL has a sensitivity of 79.5% and specificity of 75.0%. Mean ascites pro-BNP in patients with cardiac diseases were 2365.9 ± 1903.7 pg/mL, in patients with portal hypertensive (non-cardiac) ascites were 750.5 ± 3936.2 pg/mL and in patients with nonportal hypertension were 810.3 ± 2315.1 pg/mL (p=0.000). Cut-off value for ascites pro-BNP was calculated as 720.8 pg/mL in ROC analysis area under curve (AUC) as 0.898. Conclusion: In patients with cirrhosis, cholesterol cut off value was estimated as 50 mg/dL and in patients with malign ascites was also 50 mg/dL. Ascites pro-BNP higher than 720 pg/mL must be investigated for cardiac pathologies. These parameters must be in our routine work-up.