This document discusses abdominal tuberculosis, providing information on pathogenesis, clinical presentation, diagnosis, and management. Some key points: - Abdominal TB can involve the gastrointestinal tract from mouth to anus, as well as the peritoneum and pancreatobiliary system. Extrapulmonary TB, including abdominal TB, is more common in HIV-positive patients. - Common symptoms include abdominal pain, fever, weight loss, and changes in bowel habits. Ileocecal region is most commonly involved site. - Diagnosis is challenging as findings are non-specific. Investigations include ascitic fluid analysis, colonoscopy, laparoscopy, and histopathology of biopsy samples. -

1. ABDOMINAL TUBERCULOSIS

2. Introduction
 TB can involve any part of GIT from mouth to
anus, peritoneum & pancreatobiliary system.
 Very varied presentation possible ⇒
TB of GIT- 6th most frequent extrapulmonary site.

3. HIV & TB
 Before era of HIV infection > 80% TB
confined to lung
 Extrapulmonary TB increases with HIV
 40 –60% TB in HIV+ pt - extrapulmonary
 Globally, propotion of coinfected pt > 8 %
 ~ 0.4 million people in India coinfected.
 16.6% abdominal TB pt in Bombay HIV +.

4. Incidence & severity of
abdominal TB will increase with
the HIV epidemic

5. Pathogenesis
 Mechanisms by which M. tuberculosis reach the
GIT:
 Hematogenous spread from primary lung focus
 Ingestion of bacilli in sputum from active pulmonary focus.
 Direct spread from adjacent organs.
 Via lymph channels from infected LN

6.  Most common site - ileocaecal region
 Increased physiological stasis
 Increased rate of fluid and electrolyte absorption
 Minimal digestive activity
 Abundance of lymphoid tissue at this site.

7. Distribution of tuberculous lesions
Ileum > caecum > ascending colon > jejunum
>appendix > sigmoid > rectum > duodenum
> stomach > oesophagus
 More than one site may be involved

8.  Peritoneal involvement occurs from :
 Spread from LN
 Intestinal lesions or
 Tubercular salpingitis
 Abdominal LN and peritoneal TB may occur without
GIT involvement in ~ 1/3 cases.

9. Peritoneal tuberculosis occurs in 3 forms.
• Wet type - ascitis.
• Encysted (loculated) type - localized swelling.
• Fibrotic type - masses composed of mesenteric &
omental thickening, with matted bowel loops.

10. Clinical Features
 Mainly disease of young adults
 ~ 2/3 of pt. are 21-40 yr old
 Sex incidence equal.
 Clinical presentation → Acute / Chronic / Acute on
Chronic.

11.  Constitutional symptoms
 Fever (40%-70%)
 Weight loss (40%-90%)
 Anorexia
 Malaise
 Pain (80%-95%)
 Colicky (luminal stenosis)
 Continous ( LN involvement)
 Diarrhoea (11%-20%)
 Constipation
 Alternating constipation and diarrhoea

12. Tuberculosis of esophagus
 Rare ~ 0.2% of total cases
 By extension from adjacent LN
 Low grade fever / Dysphagia / Odynophagia /
Midesophageal ulcer
 Mimics esophageal Ca

13. Gastroduodenal TB
 Stomach and duodenum each ~ 1% of total cases
 Mimics PUD - shorter history, non response to t/t
 Mimics gastric Ca.
 Duodenal obstruction - extrinsic compression by tuberculous
LN
 Hematemesis / Perforation / Fistulae / Obstructive jaundice
 Cx-Ray usually normal
 Endoscopic picture - non specific

14. Ileocaecal tuberculosis
 Colicky abdominal pain
 ‘Ball of wind’ rolling in abdomen
 Borborygmi
 Right iliac fossa lump - ileocaecal region,
mesenteric fat and LN

15. Obstruction
 Most common complication
Pathogenesis
 Hyperplastic caecal TB
 Strictures of the small intestine--- commonly multiple
 Adhesions
 Adjacent LN involvement → traction, narrowing and fixation of
bowel loops.

16. Perforation
 2nd
commonest cause after typhoid
 Usually single and proximal to a stricture
 Clue - TB Chest x-ray, h/o SAIO
 Pneumoperitoneum in ~ 50% cases

17. Malabsorption
 Pathogenesis
 bacterial overgrowth in stagnant loop
 bile salt deconjugation
 diminished absorptive surface due to ulceration
 involvement of lymphatics and LN

18. Segmental / Isolated colonic tuberculosis
 Involvement of the colon without involvement of the
ileocaecal region
 9.2% of all cases
 Multifocal involvement in ~ 1/3 (28% to 44%)
 Median symptom duration <1 year

19. Colonic tuberculosis
 Pain --- predominant symptom ( 78%-90% )
 Hematochezia in < 1/3 - usually minor
Overall, TB accounts for ~ 4% of LGI bleeding
 Other features--- fever / anorexia / weight loss /
change in bowel habits

20. Rectal and Anal Tuberculosis
 Hematochezia - most common symp. Due to mucosal
trauma by stool
 Constitutional symptoms
 Constipation
 Rectal stricture
 Anal fistula – usually multiple

21. Diagnosis and Investigations
 Non specific findings---
 Raised ESR
 Positive Mantoux test
 Anemia
 Hypoalbuminaemia

22. Immunological Tests
 ELISA
Response to mycobacteria variable & reproducibility poor
Value of immunological tests remain undefined

23. Ascitic fluid examination
 Straw coloured
 Protein >3g/dL
 TLC of 150-4000/µl, Lymphocytes >70%
 SAAG < 1.1 g/dL
 ZN stain + in < 3% cases
 + culture in < 20% cases

24. Adenosine Deaminase (ADA)
Aminohydrolase that converts adenosine  inosine
 ADA increased due to stimulation of T-cells by
mycobacterial Ag
 Serum ADA > 54 U/L
 Ascitic fluid ADA > 36 U/L
 Ascitic fluid to serum ADA ratio > 0.985
 Coinfection with HIV → normal or low ADA

25. Colonoscopy
Colonoscopy - mucosal nodules & ulcers
 Nodules
 Variable sizes (2 to 6mm)
 Non friable
 Most common in caecum especially near IC valve.
 Tubercular ulcers
 Large (10 to 20mm) or small (3 to 5mm)
 Located between the nodules
 Single or multiple
 Transversely oriented / circumferential contrast to Crohns
 Healing of these ‘girdle ulcers’→ strictures
 Deformed and edematous ileocaecal valve

32. Colonoscopic Diagnosis
 8 –10 Bx from ulcer edge
 Low yield on histopath as mainly submucosal disease
 Granulomas in 8%-48%
 Caseation in ~ 1/3 (33%-38%) of + cases
 AFB stains - variable
 Culture positivity in 40%
 Combination of histology & culture ⇒ diagnosis in 60%

33. Laparoscopic Findings
 Thickened peritoneum with tubercles-
 Multiple, yellowish white, uniform (~ 4-5mm) tubercles
 Peritoneum is thickened & hyperemic
 Omentum, liver, spleen also studded with tubercles.
 Thickened peritoneum without tubercles
 Fibro adhesive peritonitis
 Markedly thickened peritoneum and multiple thick adhesions
Caseating granulomas + in 85%-90% of Bx

35. Management
 ATT for at least 6 months including 2 months of Rif, INH,
Pzide and Etham
 However in practice t/t often given for 12 to 18 months
 2 recent reports → obstructing lesions may relieve with ATT
alone
However most will need surgery