Our aim was to explore the relationship between liver cirrhosis (LC), portal hypertension (PH), and diabetes mellitus (DM). LC displayed hemodynamic alterations reflected by signs and symptoms of hypertension and hyperdynamic circulation. Portal hypertension also caused splenomegaly because of the blood flow into the spleen from the portal vessels and portal flow. The alcoholic cirrhosis displayed abnormal values (AST, ALT, AST/ALT, albumin, ammonia, bilirubin, blood platelet, erythrocytes, glucose, Hb, international normalized ratio (INR), PT, prothrombin index (PI), thymol test, white blood cell (WBC) count), which demonstrated the presence of portal hypertension, ascites, DM, infection, and coagulopathy. The evaluation of liver enzymes and other laboratories data helped to determine the severity of the condition and prognosis. Diabetes appeared to be less affecting the prognosis of patients with cirrhosis than LC itself, showing that hepatocellular failure was largely responsible for patients’ mortality rather than diabetes and its complications. Patients displayed a BMI correlating obesity, although affected by concomitant diseases that commonly cause a severe weight loss. The elevated BMI in this case was accentuated by the presence of ascitic fluid, which is responsible for the increase in weight and the inaccurate BMI evaluation. Ascites affect patients’ recovery from liver diseases. Obese patients with cirrhosis can be related to have a large amount of ascites and that physicians should be expecting to notice changes in their BMI pre- and postoperatively, subsequently making a prior classification as obese inappropriate. Disease severity could be assessed through the evaluation of PH stage, which was characterized by a significant depletion of WBC and as well as platelet counts.