Tuberculosis of the gastrointestinal tract and peritoneum.

Gastrointestinal and peritoneal tuberculosis remain common problems in impoverished areas of the world, but is relatively infrequent in the United States. A resurgence of tuberculosis in America since the mid-1980s means that clinicians will continue to see cases. Immigrants and AIDS patients are two population groups at particular risk for abdominal tuberculosis in this country; the urban poor, the elderly, and Indians on reservations are others. The symptoms and signs of GI and peritoneal tuberculosis are nonspecific, and unless a high index of suspicion is maintained, the diagnosis can be missed or delayed resulting in increased morbidity and mortality. Only 15-20% of patients have concomitant active pulmonary tuberculosis. Tuberculous peritonitis needs to be considered in all cases of unexplained exudative ascites. Laparoscopy with directed biopsy currently is the best way to make a rapid specific diagnosis. The measurement of ascites adenosine deaminase levels represents a major diagnostic advance in tuberculous peritonitis, particularly in underdeveloped areas where the affliction is common and laparoscopy may not be available. With greater experience, this testing procedure could also supersede invasive studies in western countries, particularly in high-risk patient groups. The commonest sites of tuberculous involvement of the GI tract are the ileocecal area, the ileum and the colon, although any area of the gut can be involved. If the area of affected gut is within reach of the flexible endoscope, rapid diagnosis may be possible with biopsy (if acid-fast bacilli or caseating granulomas are seen). Not infrequently, the disease is not considered until it is diagnosed at the time of surgery. In countries with a high prevalence of intestinal tuberculosis, a therapeutic trial of antituberculous drugs may be reasonable if the clinical picture is compatible. The diagnosis of tuberculous enteritis can be taken as highly probable if the patient responds to treatment and this is followed by no recurrence. Serologic tests for diagnosing tuberculosis are being improved and evaluated in intestinal tuberculosis. Gastrointestinal and peritoneal tuberculosis are treated with antituberculous drugs. Surgery is reserved for complications or uncertainty in diagnosis. Six-, 9-, and 18- to 24-month regimens are all effective for extrapulmonary tuberculosis. Standard therapy of at least 9 months duration is also effective in most AIDS patients who are started on appropriate treatment in a timely fashion and who are compliant. The potential for multidrug resistance needs to be kept in mind and accounted for.