Numerous abdominal manifestations were noted among 600 patients undergoing treatment at Hospital Laennec for various stages of infection by the acquired immunodeficiency virus. These included violent abdominal pain in 30% of cases, the development of abdominal lymphoma, and occasionally alarming pseudo-surgical syndromes. Diagnosis is difficult, all the more so since authentic emergencies may be aggravated by the immunodeficiency state. 18 cases were collected in 3 years and included 6 cases of acute cholecystitis and 2 of appendicitis. The gangrenous and extensive nature of infection was generally noted and required appropriate antibiotic therapy.