Clinical Features of Abdominal Tuberculosis
Abdominal tuberculosis presents with a classic triad of fever (70-84%), abdominal pain (65-88%), and weight loss (36-68%), with the ileocecal region and terminal ileum involved in 50-90% of gastrointestinal cases. 1
Primary Clinical Symptoms
- Fever is present in 70-84% of cases, often accompanied by night sweats (30%) 1, 2
- Abdominal pain occurs in 65-88% of patients, typically chronic and localized to the right lower quadrant or periumbilical region 1, 3
- Weight loss affects 36-68% of patients and may be accompanied by anorexia (30-98%) 1, 4
- Abdominal swelling is reported in 67% of cases, often related to ascites 2
- Altered bowel habits including diarrhea (39-47%), constipation, or alternating patterns occur in 38-47% of patients 2, 3
Physical Examination Findings
- Ascites is present in 30-67% of cases and may be free or loculated 1, 2
- Abdominal tenderness is a common finding, particularly in the right lower quadrant 5, 4
- Palpable abdominal mass occurs in 13% of patients, often in the right iliac fossa due to ileocecal involvement 5, 2
- Fever is documented on examination in 73% of cases 2
- Doughy abdomen from peritoneal involvement is found in 9% of patients 2
- Cachexia and palleness reflect chronic disease and anemia (64.2% of cases) 5, 3
Anatomical Distribution
- The ileocecal region and terminal ileum are the most critical sites, involved in 50-90% of gastrointestinal TB cases 6, 1, 7
- Peritoneal tuberculosis is the most common form of abdominal TB, involving the peritoneal cavity, mesentery, and omentum 6
- Liver and spleen show the greatest involvement among solid organs (70% of solid organ cases) 6
- Multiple sites may be affected simultaneously, including gastrointestinal tract (58-60% of abdominal TB), lymph nodes (23%), and solid organs (10%) 6, 1
Laboratory Abnormalities
- Anemia is present in 64.2% of patients 3
- Tuberculin skin test (PPD) is positive in only 27-52% of cases, making it unreliable for diagnosis 2, 3
- T-SPOT test has much higher sensitivity at 86.4% and should be used preferentially when available 3
- TB antibody tests have low sensitivity (34.6%) 3
- Ascitic fluid analysis is diagnostic on smear/culture in only 33% of cases despite frequent ascites 2
Radiologic Findings
CT Scan Findings (Gold Standard Imaging)
- Abnormal CT abdomen is found in 80% of cases 2
- Ascites with thin mobile septa is a characteristic finding 8
- Smooth peritoneal thickening and enhancement suggests peritoneal involvement 8
- Conglomerate lymph nodes >20mm with peripheral enhancement and central hypodensity (necrosis) are highly suggestive 9, 8
- Misty mesentery with large lymph nodes is a typical pattern 8
- Smudged omental involvement may be visible 8
- Ileocecal changes including wall thickening and luminal narrowing 8
Endoscopic Findings
- Ulcerative type (52.7% of cases) is the most common endoscopic pattern 3
- Circumscribed annular ulcers occur in 52.7% of cases 3
- Patulous (gaping) ileocecal valve is seen in 65.5% of patients 3
- Mucosal hyperemia and edema affect 87.2% of cases 3
- Polypoid or nodular hyperplasia is present in 45-58% of patients 3
- Luminal stenosis occurs in 29.1% of cases and may lead to obstruction 3
Critical Diagnostic Pitfalls
- Up to 85% of patients with abdominal TB have no pulmonary involvement, so absence of lung disease does not exclude the diagnosis 6, 1, 7
- Clinical presentation mimics Crohn's disease, particularly in the ileocecal region, but night sweats and positive tuberculin skin test favor TB 1
- Treating presumed Crohn's disease with immunosuppression when the patient actually has TB can lead to fulminant TB progression and death 1
- The presentation is highly variable and non-specific, mimicking infectious, inflammatory, and even neoplastic conditions 6