Abdominal tuberculosis

Details about abdominal TB and difference between TB & Crohns disease briefly......

1. ABDOMINAL TUBERCULOSIS DR. MD. KAWSER HAMID Assistant Registrar Department of Gastroenterology SSMC & MH

2. INTRODUCTION Abdominal TB is an increasingly common disease that poses diagnostic challenge, as the nonspecific features of the disease which may lead to diagnostic delays and development of complications. The spread of the disease is aided by poverty, overcrowding and drug resistance.

3. Approximately 15% - 25% of cases with abdominal TB have concomitant pulmonary TB. Abdominal involvement may occur in the gastrointestinal tract, peritoneum, lymphnodes or solid viscera.

4. PATHOPHYSIOLOGY Tubercle bacilli enter the GI tract Mucosal layer can be infected Formation of epithelioid tubercles in lymphoid tissue of submucosa . after 2-4 wks Caseous necrosis of the tubercle lead to ulceration of overlying mucosa. later Spread into deeper layers and into adjacent lymphnodes & peritoneum.

5. Modes of involvement in abdominal tuberculosis By ingestion Infected food or milk - Primary intestinal TB Infected sputum - Secondary intestinal TB Hematogenous spread from distant tubercular focus Contagious spread from infected adjacent foci Through lymphatic channel

6. Classification of abdominal tuberculosis Tubercular lymphadenopathy Peritoneal tuberculosis Acute Chronic Wet ascitic type Fixed fibrotic type Dry plastic type Encysted/ loculated type

7. Visceral tuberculosis Liver, pancreas, spleen etc. Gastrointestinal TB Esophageal tuberculosis Gastric tuberculosis Duodenal tuberculosis Jejunal and ileocecal TB Colorectal tuberculosis

8. CLINICAL PRESENTATION Tubercular lymphadenopathy Most common manifestation of abdominal TB. Can affect any lymph node of abdomen. Most commonly – mesentaric , omental , those at porta hepatis , along with celiac axis and peripancreatic .

9. As a mass or lump of matted lymph nodes in the central abdomen or as vague abdominal pain. There is associated fever, night sweats and malaise .

10. Peritoneal tuberculosis Wet ascitic type : more common and associated with ascitis . Fixed fibrotic type : relatively less common and characterized by involvement of omentum & mesentary . Dry plastic type : characterized by peritoneal reaction, peritoneal nodules & presence of adhesions.

11. Visceral tuberculosis Occurs in 15% - 20% of all patients with abdominal TB. Genitourinary system is most commonly involved followed by liver, spleen and pancreas. Mode of spread – hematogenous route. Isolated involvement is relatively uncommon.

12. Gastrointestinal tuberculosis Most common site is ileocecal region , followed by jejunum and colon. Esophagus, stomach and duodenum are rarely involved. Three types of intestinal lesions are commonly seen – ulcerative,stricturous and hypertrophic.

13. E sophageal TB Extremely rare, common in AIDS patients. Middle third of the esophagus is most commonly affected due to proximity to mediastinal LNs. Symptoms are usually retrosternal pain, dysphagea & odynophagea . Rarely patient may present with bronchoesophageal fistula or diverticulum.

14. Gastric TB Primary involvement is rare due to bactericidal property of gastric acid, thick intact mucosa & scarcity of lymphoid tissue in gastric wall. Most common type is ulcerative lesion along lesser curvature & pylorus. Non specific symptoms like epigastric discomfort, wt loss & fever or may be gastric outlet obstrution .

15. Duodenal TB Most common site is third part of duodenum. Can be extrinsic or intrinsic. Most patients have symptoms of duodenal obstruction and history of dyspepsia. Complications may be perforation, fistula, obstructive jaundice & choledocho -duodenal fistula.

16. Jejunal and ileocecal TB Most common site of GI involvement is ileocecal region (64%). The terminal ileum, ileocecal junction & caecum are concomitantly involved in majority of cases. Clinical features – colicky abdominal pain, borborygmi & vomiting. Common complications are bowel obstruction & perforation.

17. The terminal ileum is more commonly involved because  Stasis. Presence of abundant lymphoid tissue. Increased rate of absorption at this site. Closer contact of bacili with mucosa.

18. Colorectal TB Isolated involement of colon is 10.8%. Multifocal involvement is seen in 28% - 44% of cases with colorectal TB. Most common site of involvement is caecum but usually contiguous with terminal ileum and IC junction. C/ Fs – abdominal pain followed by loss of weight & appetite and altered bowel habits.

19. Type Clinical presentations 1.Ulcerative Chronic diarrhea, malabsorption , intestinal perforation (occasional).Rectal bleeding is rare but reported occasionally in colonic tuberculosis. 2. Hypertrophic Intestinal obstruction or an abdominal ( ileocaecal ) lump. 3 . Stricturous / constrictive Recurrent subacute intestinal obstruction (e.g. vomiting , constipation,distention and colicky pain). There may be associated gurgling sounds or feeling of moving ball of wind in the abdomen and visible distended intestinal loops with visible peristalsis. These symptoms get relieved with passage of flatus /stool . Sometimes, acute int. obstruction may occur. 4. Anorectal Stricture or fistula-in- ano .

20. 5. Gastroduodenal Peptic ulcer with or without gastric outlet obstruction or perforation . 6. Liver and spleen Hepatosplenomegaly usually a part and parcel of disseminated TB is accompanied with fever, night sweats and decreased or loss of appetite. Microscopic involvement shows granulomatous hepatitis . 7. Peritoneum Abdominal distention and ascites, sometimes there may be a soft cystic lump due to loculated ascites. 8. Lymph node As a mass or lump of matted lymph nodes in the central abdomen or as vague abdominal pain associated fever, night sweats & malaise .

21. Diagnosis New criteria for the diagnosis were suggested by Lingenfelser as follows : i . Clinical manifestations suggestive of TB ii . Imaging evidence indicative of abdominal TB iii . Histopathological or microbiological evidence of TB and/or iv . Therapeutic response to treatment.

22. Investigations Blood examination: may show varying degree of anemia , leucopenia and raised ESR. 2. Serum biochemistry: Serum albumin level may be low . Serum transaminases are normal . A high level of serum ALP may be observed in hepatic tuberculosis.

23. 3. Montoux test : Supportive evidence to the diagnosis of abdominal TB in 55% - 70% (if positive). Negative result may be observed in one-third of patients. Both false positive & false negative reactions are common. Limited value due to its low sensibility & specificity.

24. 4. Imaging techniques Plain X-ray of abdomen & chest : Plain X-ray abdomen may show presence of multiple air fluid levels and dilated loops of gut in case of acute or sub-acute obstruction. Calcification in the abdominal lymph nodes also indicates TB. Plain X-ray chest done simultaneously but remind this, normal CXR doesn’t rule out the diagnosis.

25. (A) - SUPINE (B) - ERECT

26. Barium studies It has been documented that barium studies are useful in 75% patients with suspected intestinal tuberculosis. Different barium studies are used to diagnosis at the basis of involved site. Barium swallow Barium meal follow through Barium enema

27. In esophageal TB, barium swallow may show ulceration, stricture or traction diverticulum.

28. Long segment circumferential n arrowing in first and second p art of duodenum.

29. Ba meal follow through Best diagnostic test for intestinal lesions. In Ba studies features may be seen : Accelerated intestinal transit. Hyper-segmentation of Ba column(chicken intestine) Luminal stenosis with smooth but stiff contours(hourglass stenosis) Multiple strictures with segmental dilatation of bowel loops and matted.

30. Findings of barium meal follow through study in intestinal TB Group I Highly suggestive of intestinal tuberculosis if one or more of the following features are present. • Deformed ileocaecal valve with dilated ileum • Contracted caecum with abnormal ileocaecal valve or terminal ileum. • Stricture of ascending colon with shortening or involvement of ileocaecal region. Group II Suggestive of intestinal tuberculosis if one of the following is present: • Contracted caecum • Ulceration or narrowing of terminal ileum • Stricture of ascending colon • Multiple sites of narrowing and dilatation leading to formation of small bowel loops. Group III Non-specific changes Features of adhesions, dilatation and mucosal thickening of small bowel loops Group IV Normal study

31. Barium enema study The thickening of ileocaecal valve with triangular appearance, pulled up caecum and/or wide gaping of the valve with narrowing of the terminal ileum (an inverted umbrella sign, or Fleischner’s sign. Rapid transit and lack of retention of the barium in an inflamed segment of the small bowel constitutes Stierlin’s sign ”) A persistent narrowing or stenosis of the bowel leads to consistent narrowing of stream of barium called the “ string sign ”.

32. Ultrsonography Intra-abdominal fluid which may be free or loculated . “Club sandwich” or “sliced bread” sign due to interloop ascitis . Lymphadenopathy- discrete or matted. Bowel wall thickening in ileocecal region which is uniform & concentric. Pseudo kidney sign.

33. Multiple enlarged conglomerate lymphnodes in retroperitoneum with hypoechoic centers due to caseation.

34. CT scan Abdominal CT is better than USG. Contrast enhanced CT is preferred. Most common CT finding is concentric mural thickening of ileocecal region, with or without proximal intestinal dilatation. It also shows abdominal lymphadenopathy involving predominantly mesentaric , para -aortic, peri -portal.

35. Tuberculosis Crohn’s Disease Mural thickening without stratification. Strictures concentric. Fibrofatty proliferation of mesentary very rare. No vascular engorgement in mesentary . High dense ascitis . Mural thickening with stratification. Strictures eccentric. Fibrofatty proliferation of mesentary . Hypervascular mesentary . Abscesses.

36. Colonoscopy The TB ulcers tend to be circumferential and are usually surrounded by inflamed mucosa. A patulous valve with surrounding heaped up folds or a destroyed valve with a fish mouth opening is more likely to be caused by TB than CD. Site of frequent involvement- 32% ileocecal region, 28% ileocecal region with ascending colon, 26% segmental involvement.

37. Laparoscopy Laparoscopy facilitates an accurate diagnosis in 80% - 90% of patients. Laparoscopic biopsy may reveal AFB in 75% patients and caseating granuloma in 85% - 90% patients. It is effective method due to direct visualization of thickened inflammed peritoneum and adhesion or fibrous strands within turbid ascitis .

38. Histopathology In case of TB, typically shows granulomatous inflammation. Granuloma characteristically contains epithelioid macrophages, Langhans giant cells and lymphocytes. The center of granuloma often have charateristic caseation (cheese-like) necrosis. Above mentioned features strongly suggests TB but not pathognomonic.

39. TB granuloma Caseating . 5 or more granulomas in biopsies from one segment. Granulomas >400 µm in diameter. Located in sub mucosa or in granulation tissue, often epithelioid histiocutes . Confluent granulomas. Lymphoid cuff around granuloma. Crohn’s granuloma Non- caseating . Infrequent (<5) granulomas in biopsies from one segment. Usually < 200 µm in diameter. Located in mucosa.Poorly organized or discrete.Crypt inflammation present. No confluent granulomas. Not present.

40. Ascitic fluid study Protien : > 3 g/ dL . Total cell count : 150-4000/ µL, predominantly lymphocytes. SAAG : < 1.1 g/ dL . ADA level : > 36 U/L. ( normal or low in case of co-infection with AIDS ) Staining for AFB is positive in less than 3% of cases and positive culture is seen in only 20% of cases.

41. Newer techniques Quantiferon – TB Gold (QFT-G) Anti-Saccharomyces Cerevisiae Antibody (ASCA) T-cell Based Testing for Mycobacterium Tuberculosis (ELISPOT) Nucleic Acid Amplification. Gene Xpert Assay. MTBDR Plus. TB PCR.

42. Management Medical : All the diagnosed cases should receive 6 months anti-TB therapy which is highly effective. Now proven that 6 months therapy is as effective as 9 months therapy. Majority of ulcers, nodules, luminal narrowing, ileocecal valve deformities resolved with anti-TB after 4 weeks.

43. B. Surgical Surgeries performed in cases of non-resolving intestinal obstruction, perforation,massive bleeding and abscess or fistula formation. First type : Bypass the involved segments of bowel. Second type : Radical resection like right hemicolectomy . Third type : conservative like stricturoplasty .

44. Conclusion Abdominal TB is frequently rising extra-pulmonary TB now-a-days. The peritoneum and ileocaecal region are commonly involved in majority of the cases by hematogenous spread or through swallowing of infected sputum. The symptoms of abdominal TB can be non-specific.

45. Various imaging features and radiological signs have led to early diagnosis of this disease . Gastrointestinal TB is generally managed with medical therapy with antituberculous drugs and surgeries are usually conservative & are done only if absolutely indicated.