Pathogenesis and clinical significance of liver injury in celiac disease.

Abnormalities of liver function are one of the manifold extraintestinal manifestations of celiac disease. Although the spectrum of liver manifestations associated with celiac disease is particularly wide, two main forms of liver damage namely, cryptogenic and autoimmune, appear to be strictly related to gluten-sensitive enteropathy. The most frequent finding is represented by a cryptogenic hypertransaminasemia, observed in about a half of untreated celiac patients, as an expression of a mild liver dysfunction with a histological picture of nonspecific reactive hepatitis (celiac hepatitis) reverting to normal after 6-12 months of a strict gluten-free diet. In a few cases, when celiac disease is diagnosed, a more severe liver injury, characterized by a cryptogenic chronic hepatitis or liver cirrhosis, is present. In these patients, liver damage can still improve after a gluten-free diet institution. Moreover, a close association between celiac disease and autoimmune liver disorders has been widely demonstrated. Indeed, celiac disease has been found in 3-7% of patients with primary biliary cirrhosis, in 3-6% with autoimmune hepatitis, and in 2-3% with primary sclerosing cholangitis. Differently from cryptogenic liver injury, autoimmune liver dysfunction, found in celiac disease, does not usually improve after a gluten-free diet. Presently, it is difficult to establish if the two main kinds of liver injury found in celiac disease (cryptogenic and autoimmune) are discrete entities with a different pathogenesis or if they are an expression of the same disorder where genetic factors and the duration of gluten exposure may determine the severity and the pattern of liver injury.