[Lactulose fermentation and lactose absorption in Chilean patients with liver cirrhosis: importance for hepatic encephalopathy therapy].

BACKGROUND: Non-absorbable carbohydrates are widely used in the therapy of hepatic encephalopathy. It has been argued that their effects depend on intestinal fermentation. In some geographic areas other than Chile up to 27% of healthy inhabitants are not able to increase breath hydrogen after a lactulose load, a parameter of intestinal fermentation of carbohydrate. Lactose has been proposed as an alternative to non-absorbable disaccharides in patients with lactase deficiency. AIM: To investigate intestinal fermentation of lactulose and lactose malabsorption in Chilean patients with liver cirrhosis. PATIENTS AND METHODS: 22 healthy controls and 52 patients with liver cirrhosis (16 with hepatic encephalopathy) were prospectively studied by means of lactulose or lactose hydrogen breath tests and lactose tolerance test. MAIN RESULTS: In the control group, 19% were non-hydrogen excretors after lactulose, meanwhile a significant rise in breath hydrogen concentration was observed in all cirrhotic patients (p < 0.01). Lactose tolerance test was indicative of lactase persistance in 37% of cirrhotics and in 43% of controls (NS). Finally, 41% of cirrhotics and 50% of controls had a normal lactose hydrogen breath test (NS). These results were not significantly modified by the presence of hepatic encephalopathy. CONCLUSION: Our data suggest that a lack in bacterial fermentation is not a cause of lactulose therapy failure in Chilean patients with hepatic encephalopathy. Lactose might be an inappropriate substitute to lactulose treating a significant proportion of patients with this condition in our country.