Liver cirrhosis is a significant cause of death in Italy and one of the most frequent causes of hospitalization. The burden of cirrhotic patients on the National Health System is extremely high due to the frequent need for medical care. Acute peptic ulcer and upper gastrointestinal bleeding reportedly occur in over one-third of cirrhotic patients. Since Helicobacter pylori (H. pylori) infection strongly correlates with peptic ulcer, we wished to ascertain the prevalence of H. pylori infection in cirrhotic patients. In a case-control study we looked for this infection in 45 consecutive male patients suffering from hepatitis B virus (HBV)-related cirrhosis and 310 sex and age matched blood donors resident in the same area. Antibodies against H. pylori were present in 40/45 (89%) patients and 183/310 (59%) blood donors (P<0.001). This very high prevalence of H. pylori may explain the frequent occurrence of gastroduodenal ulcer in cirrhotic patients. (See Editorial p. 203)