AIDS is frequently expressed through gastrointestinal o abdominal symptoms. In addition, patients with AIDS or ARC frequently have hepatic and biliary symptoms, while pancreatic alterations are found in 4-30% of patients hospitalised for AIDS. Since AIDS patients are immunodepressed, they are subject to opportunistic infection often multifocal and the pathological processes can be present simultaneously. About 2/3 of patients have enlarged liver, steatosis, splenomegaly, lymphoadenopathy, cholecystic and biliary tract abnormalities, alterations of liver function tests, and abdominal discomfort in the upper right quadrant. Jaundice is rare and hepatic failure is not common. Hepatic biopsy is often necessary to establish the diagnosis. The hepatic localisation of an opportunistic pathogenic agent is generally a sign of systemic dissemination which is expressed as granulomatous hepatitis (atypical mycobacteria, frequently mycobacterium avium, or M. tuberculosis representing the reactivation of latent diseases), peliosis hepatis, infection from CMV, HSV, EBV, Pneumocystis carinii, and mycotic infections. Coinfections with the hepatic virus (HBV, HDV, HCV) are also often present. Pharmacological damage may also be present (mainly caused by antibiotic therapies). Neoplasia are rare (hepatic Kaposi's sarcoma associated with cutaneous and gastrointestinal manifestations, or generally metastatic lymphoma). Damage of the biliary tract usually develops after other manifestations of the illness; the most frequent pictures are cholestatic syndromes and cholangitis, while cholecystitis and jaundice are rare. Pancreatic lesions are generally asymptomatic. They are diagnosed during autopsy and are caused principally by opportunistic agents.