This article is a sub-article of Tuberculosis.
Intestinal Tuberculosis is also known as TB of the intestine or TB infection of the intestine. Tuberculosis is primarily a Lung Infection, but it can infect other areas of the body as well. Intestinal Tuberculosis frequently complicates Lung Infections with Tuberculosis. In addition, milk, which contains tuberculi bacteria, may also infect the intestine.
Intestinal tuberculosis occurs mainly in developing countries. This infection may not cause any symptoms but can cause abnormal swelling of tissues in the abdomen. This swelling may be mistaken for cancer.
Signs and Symptoms
- May have none
- Flatulence (“gas”)
- Food intolerance
- Abdominal cramps in lower right abdomen
- Abdomen distends after eating
- Weight loss
Mode of Transmission
- Mild right lower abdominal tenderness
- X-Rays may show colon irregularities
- Colonoscopy with biopsy may prove the diagnosis
Pathogen and routes of spread
Routes of GI infection include the following: (1) spread by means of the ingestion of infected sputum, in patients with active pulmonary TB and especially in patients with pulmonary cavitation and positive sputum smears; (2) spread through a hematogenous route from tuberculous focus in the lung to submucosal lymph nodes; and (3) local spread from surrounding organs involved by primary tuberculous infection (eg, renal TB causing fistulas into the duodenum).
Pathologically Intestinal TB is characterized by inflammation and fibrosis of the bowel wall and the regional lymph nodes. Mucosal ulceration results from necrosis of Peyer patches, lymph follicles, and vascular thrombosis. At this stage of the disease, the changes are reversible and healing without scarring is possible. As the disease progresses, the ulceration becomes confluent, and extensive fibrosis leads to bowel wall thickening, fibrosis, and pseudotumoral mass lesions. Strictures and fistulae formation may occur.
The serosal surface may show nodular masses of tubercles. The mucosa is inflamed with hyperemia and edema similar to that observed in Crohn’s disease. In some cases, aphthous ulcers may be seen in the colon. Caseation may not always be seen in the granuloma, especially in the mucosa, but it is almost always seen in the regional lymph nodes.
On gross pathologic examination, intestinal TB can be classified into 3 categories:
1. The ulcerative form of TB is seen in approximately 60% of patients. Multiple superficial ulcers are largely confined to the epithelial surface. This is considered a highly active form of the disease, with the long axis of the ulcers perpendicular to the long axis of the bowel.
2. The hypertrophic form is seen in approximately 10% of patients and consists of thickening of the bowel wall with scarring; fibrosis; and a rigid, masslike appearance that mimics that of a carcinoma.
Pasteurizing of milk may help prevent infection.
See TB Prevention for more information.
Hemorrhage and perforation are recognized complications of intestinal TB, although free perforation is less frequent than in Crohn’s disease.
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