Abdominal tuberculosis is usually associated to pulmonary tuberculosis. The most frequent gastrointestinal form is ulcerative illeocecal tuberculosis. Esophageal, gastric and duodenal locations are rare; jejunal and proximal ileal tuberculosis are rare during tuberculous peritonitis. The most common form with liver and spleen involvement is miliary tuberculosis, the macronodular form being rare. Tuberculous peritonitis is a common manifestation of abdominal tuberculosis with various aspects according to the presence of ascitis and the predominant fibrotic reaction. Most common abdominal manifestation is represented by lymph node involvement with four patterns recognized on CT. In AIDS patients together with Mycobacterium tuberculosis infection, there may be Mycobacterium avium complex infection with often indistinguishable imaging findings. Patterns are similar to those of immunocompetent patients, except for markedly immunocompromised subjects in whom disseminated forms are observed.