Little is known about the clinical significance of chronic alanine aminotransferase (ALT) elevation in HIV-infected patients without hepatitis B and C coinfection. Study aim is first to evaluate the prevalence of liver fibrosis and cirrhosis in HIV-infected patients with chronic ALT elevation and no chronic viral hepatitis using non-invasive diagnostic tests and second to find associated factors with significant fibrosis and cirrhosis. In a second longitudinal part we intend to assess fibrosis progression within 1 and 3 years.