IMAGING IN ABDOMINAL TUBERCULOSIS

ABDOMINAL TUBERCULOSIS : ETIOLOGY, SPREAD AND IMAGING FEATURES....ON CONVENTIONAL AND CROSS SECTIONAL IMAGING

1. Imaging in
Abdominal
Tuberculosis
Presenter : Dr. Navni
Moderator : Dr. Ravi

2. • Tuberculosis can affect any organ system,
particularly in immunocompromised individuals.
•Can be divided into
Pulmonary TB (85-90 %)
Extrapulmonary TB (10-15% )

3. Extrapulmonary TB
•Genitourinary TB (MC)
•Bone and joint TB
•Miliary TB
•Meningeal TB
•Gastrointestinal ( abdominal ) TB : 3-4%

4. Abdominal Tuberculosis
•Defined as tuberculosis infection of the abdomen
involving the peritoneum and its reflections,
gastrointestinal tract, abdominal lymphatics and
solid visceral organs.
•Causative organisms : M. tuberculosis hominis, M.
bovis, Atypical mycobacterium (MAIC)

5. Routes of infection
•Ingestion of milk
•Swallowing of sputum in active PTB
•Hematogenous spread from active pulmonary
lesion, miliary tuberculosis to submucosal
lymph nodes
•Contiguous spread from infected foci like
fallopian tubes, mesenteric lymph node
•Very rarely as a consequence of peritoneal
dialysis

6. Only 15 % of patients with
abdominal TB have pulmonary
disease !!!!

8. Clinical spectrum
•Disease of young
•Slight female preponderance
•Children : more gastrointestinal disease
•Adults : adhesive peritoneal and lymph nodal
disease
•Can present as acute, chronic, acute on
chronic
•Most patients have constitutional symptoms

10. Classification of Abdominal Tb
1.Peritoneal tuberculosis and Tuberculosis of the
mesentery and its contents
2.Lymph node tuberculosis
3.Gastrointestinal tuberculosis
4.Tuberculosis of the solid viscera : Liver ,
Pancreas, Spleen

11. 1. Tubercular peritonitis
•Originate primarily as result of reactivation of
latent TB foci in the peritoneum or secondary
to a ruptured lymph node or due to tubercular
salpingitis
•The condition is subdivided into three main
types—
Wet ascitic type
Fibrotic fixed type
Dry /plastic type

12. Wet ascitic type
•Most common type ( 90%)
•Large amounts of free or loculated ascitic fluid
•USG: fine, multiple ,complete or incomplete,
mobile strands of fibrin and debris in ascitis

13. Wet ascitic type
• CT : usually slightly
hyperattenuating (20–45
HU) relative to water due to
its high protein and cellular
content
• Ascites (arrows) that is
hyperattenuating relative to
urine within the bladder
(arrowheads).

14. Fibrotic fixed type
• Large omental and
mesenteric cake like
masses with matting of
bowel loops.
•Occasionally ascitis may
be present
• CT :Omental thickening
(arrows) and ascitis (*)

15. Dry/ Plastic type
• Mesenteric thickening,
fibrous adhesions, and
caseous nodules.
•The omentum appears
smudged, caked, or
thickened (arrow
heads)
•Peritoneal thickening
with associated
enhancement occurs

16. Omentum
•Omental thickening seen in both TB and
peritoneal carcinomatosis
•TB : thin omental line ( fibrous wall covering
the infiltrated omentum )
•Peritoneal carcinomatosis : Irregularly
thickened outer contour of the infiltrated
peritoneum

19. Small bowel mesentry
•Mesentric nodular lesions ( solid or cystic
nodules , lymph node or abscess )
•Mesentric thickening ( > 15mm )
•Loss of normal mesentric configuration

20. USG
STELLATE SIGN
•Fixed loops of bowel
and mesentry standing
out as spokes radiating
out from the mesentric
root
CLUB SANDWICH SIGN
•Due to localised or focal
ascites radially oriented
bowel loops due to
local exudation from
inflamed bowel or
ruptured lymph nodes

21. CT
Large volume of high density ascitic fluid (*). It is also visible pronounced
peritoneal and
mesenteric thickening and enhancement (arrows).

22. Mesenteric thickening, with loss of normal mesenteric architecture and increased
vascularity (arrows). Thickened mesentery also shows contrast enhancement. Small
volume of ascites in the left parietocolic gutter is also visible in this section (*).

23. Sclerosing encapsulating peritonitis
( Abdominal cocoon)
•Small bowel loops
congregated to the
centre of abdomen
encased by a soft tissue
density mantle

24. 2. Tubercular lymphadenitis
•Abdominal lymphadenopathy is the most
common manifestation of abdominal
tuberculosis.
•Involvement of periportal, anterior
pararenal,upper paraaortic and lesser omental
lymph nodes.
•The characteristic pattern is mesenteric and
peripancreatic lymph node group
enlargement, with multiple groups affected
simultaneously .

25. Isolated retroperitoneal LN involvement highly
uncommon !!!!
Dorfman et al Radiology,1991 (29)

26. USG
•Discrete or
conglomerate masses
•Mixed heterogeneous
echotexture with
central hypoechoic area
•FIG : enlarged
hypoechoic nodes
(arrows) in a thickened
hyperechoic mesentery

28. USG
•D/D : Lymphoma : homogeneous hypoechoic
nodes
•Caseation and calcification : highly suggestive
of TB , uncommon in lymphoma

29. Rarely
•Biliary obstruction due to direct ductal
compression by infected nodes
•PV thrombosis and portal hypertension due to
involvement of hepatic hilar LN
•Renovascular hypertension due to vascular
compression by nodes
Caroli et al. j clin Gastroenterol 1997;25:541-43

30. Patterns of nodal enhancement on
CECT
1. Peripheral rim
enhancement with low
attenuation centre
•D/D : metastasis from
testicular tumors, head
and neck squamous cell
cancers,lymphoma,
whipples disease,
Crohns ds.

31. 2. Homogeneous
enhancement
Seen in patients with
MAIC infection and HIV
positive patients

32. 3. Inhomogeneous enhancement : less necrosis
4. Non enhancing low attenuation nodes

33. Multiple mesenteric lymphadenopathy forming a conglomerate mass (arrows)
Most enlarged nodes have central hypoenhancing areas due to necrosis.

34. A variety of patterns of contrast
enhancement on CT even within the
same nodal group may be seen in
tubercular adenitis, probably relating to
the different stages of the pathological
process !!!!

35. Role of MRI in TB
Lymphadenopathy

Differentiate enlarged nodes that are
abutting the pancreas from a cystic
neoplasm of the pancreas !!!

36. 3. Gastrointestinal tuberculosis
•Can involve any segment of bowel
•However, it almost always involves the
ileocecal region (90% of cases), usually both
the terminal ileum and the cecum

38. Esophageal TB
•Usually secondary to advanced pulmonary or
mediastinal disease
•MC involves the tracheal bifurcation
•C/F : dysphagia , odynophagia, chest pain or
cough

39. (A and B) Esophagograms showing a long
Stricture in the middle third of the esophagus with multiple diverticula

40. Mild esophageal wall thickening with
mediastinal lymphadenopathy

41. Gastric tuberculosis
•Rare ( 0.36-2.3% of patients with pulmonary
TB)
•Occurs due to spread from adjacent lymph
nodes or hematogeneous spread
•Usually affects antrum and distal body

42. Marked narrowing of the body of
stomach due to TB

43. Duodenal tuberculosis
•2 % of intestinal tb cases
•Lymph nodes causing extrinsic compression
on C loop of duodenum
•Ulcer /stricture
•Hyperplastic growth
•Incompetence of sphincter of oddi
•Perforation / fistula

44. Widening of the C loop of
duodenum

45. Long stricture of duodenum due to
TB

46. Tubercular enteritis
Stage 1
•Accelerated intestinal transit
•Disturbances in tone and peristaltic
contractions : hypersegmentation of barium
column (chicken intestine )
•Flocculation / dilution of barium
•Irregular , crenated intestinal contours
•Softened , thickened folds

47. Stage 2
•Ulcerations
•Fig : marked
spiculations in the asc
colon,caecum and
terminal ileum

48. Stage 3
•Hour glass stenosis of bowel
•Multiple strictures with segmental dilatation
•Fixity/ matting of loops

49. Ileocaecal tuberculosis
MC affected in small bowel TB because of
•Physiological statis
•Abundant lymphoid tissue
•Increased rate of absorption in the region and
closer contact of bacilli with the mucosa of the
region

50. Ileocecal involvement is
seen in 80%–90% of
patients with abdominal
tuberculosis.

51. Barium studies
•MOC for evaluating mucosal changes in
ileocecal TB.
•70-100 % sensitivity.
•Earliest finding: accelerated transit time due
to spasm and hypermotility of the bowel.

52. Fleischner sign
•Thickening of the
ileocaecal valve lips
and/or wide gaping of
the valve, with
narrowing of the
terminal ileum
•Inverted umbrella sign

53. Pulled up caecum
•Caecum becomes
conical, shrunken,
retracted out of the
illiac fossa due to
contraction of the
mesocolon

54. Goose neck deformity
•Loss of normal
ileocaecal angle and
dilated terminal ileum
appears as suspended
and hanging from a
retracted , shortened
caecum

55. Stierlin’s sign
•Conical and shrunken
cecum, widely open
ileocecal valves, narrowing
terminal ileum, rapid
emptying of diseased
segment
•Represents acute
inflammation superimposed
on a chronically involved
segment of the ileum,
caecum or ascending colon

56. String sign
•Persistent narrow
stream of barium in the
distal ileum

57. Both stierlin’s sign and string sign
are noted in Crohns disease and
should not be considered specific for
tuberculosis !!!

58. Group1: Highly s/o intestinal TB if one or more of the following
features are present
a. Deformed ileocaecal valve with dilatation of
terminal ileum
b. Contracted caecum with an abnormal
ileocaecal valve and/or terminal ileum
c. Stricture of the ascending colon with
shortening of and involvement of ileocaecal
region

59. Group 2 : suggestive if any of the following
features are present
a. Contracted caecum
b. Ulceration or narrowing of the terminal ileum
c. Stricture of the ascending colon
d. Multiple areas of dilatation, narrowing and
matting of small bowel loops

60. •Group 3 : non specific includes features of
matting,dilatation or mucosal thicekening of
small bowel loops
•Group 4 : normal study

61. USG
•Often reveals a mass made up of matted loops
of small bowel with thickened walls, diseased
omentum, mesentery and loculated ascites
•Regional lymph nodal enlargement

62. USG shows thlckened, echogenic
mesentery containing multiple enlarged
hypoechoic, discrete, and
conglomerate lymph nodes. Small
amount of ascites is seen (arrows).
Dilated, fluid-filled, thick-walled bowel loops at periphery.

63. Pseudo kidney sign
•Ileocaecal region is
pulled upto subhepatic
region

64. CT
Preferential thickening of the medial
caecal wall with an exophytic mass
engulfing the terminal ileum associated
with massive lymphadenopathy is
characteristic of tuberculosis !!!

65. Regular and concentric thickening of the ascending colon (arrow
in a) and cecum (arrow in b)

66. CT Enteroclysis
•Greater senstivity and specificity than NCCT in
detecting low grade small bowel obstruction
•Allows detection of luminal and extraluminal
pathology

67. MRI
•No added advantage
•Mucosal abnormalities are less well
demonstrated on MRI as compared to barium
Masserli G et al.Abdominal imaging 2006;29:326-34

68. Differential Diagnosis
MASS
•Appendicular mass
•Actinomycosis
•Crohns disease
•Caecal carcinoma
•Lymphoma

69. EJR 2005:55:173-80.

70. The ulceration in TB is
circumferential while that in
Crohn’s disease is along the
mesentric border !!!!

71. Colonic tuberculosis
•Involved in 9% of cases without small bowel
involvement
•Long or short segment involvement with
spiculation, rigidity, ulceration, inflammatory
polyps, perforation, fistulae, pericolic abscess
•D/D : UC, Crohns disease, amoebic colitis,
mailgnancy

73. Anorectal TB
•Fistula, stricture, chronic ischiorectal abscess
•Anal canal : ulcer fissures, fistulae, abscess,
warty growths

74. Pakistan Armed Forces Medical Journal:2012

75. 4. Visceral tuberculosis
•Hepatic Tb
•Spleenic Tb
•Pancreatic Tb

76. Hepatospleenic Tuberculosis
•Common in patients with disseminated disease and
is either micronodular- miliary or macronodular
•Miliary hepatic involvement is seen in patients with
miliary pulmonary tuberculosis
•Macronodular hepatic tuberculosis is uncommon
and occurs due to spread via portal vein or hepatic
artery from the para aortic or portal nodes.

77. In a patient with PUO, marked elevation
of serum alkaline phosphatase(3 to 6
times) with mild elevation of
S.transaminases, normal PT, S.albumin
and a slight increase in bilirubin hepatic
tuberculosis should be suspected !!!

78. Lesions are hypoattenuating at CT with irregular ill-defined margins and
minimal central but definite peripheral contrast enhancement

79. Multiple hepatic and splenic abscesses (arrows) appearing as
hypoenhancing, nodular, well defined lesions. They have a slightly rim
enhancement.

80. Spleenic involvement is common in HIV positive patients with TB,with
macronodular involvement seen in 15% of HIV positive patients.
Schunk K.Topics in MRI 2002 ;13(6): 409-25

81. • At MR imaging, these lesions are hypointense
with T1WI and hyperintense with T2WI.

82. Hepatic tuberculomas eventually tend to calcify, and the presence of calcified
granulomas at CT in patients with known risk factors and in the absence of a
known primary tumor should raise suspicion for tuberculosis.
•CT shows multiple
calcified granulomas
within the liver,
spleen, periportal
and peripancreatic
lymph nodes.

83. D/D
•Tuberculous microabscesses : metastases,
fungal infections (histoplasmosis), sarcoidosis
and lymphoma.
•Macronodular form : metastases, abscess and
primary malignancy.

84. Pancreatic tuberculosis
•Often associated with miliary tuberculosis and
occurs more often in immunocompromised
•May present as acute or chronic pancreatitis
•May mimic malignancy
•FNAC and biopsy are helpful

85. CECT : focal attenuated mass with peripheral
enhancement
USG : hypoechoic lesion
MRCP : pancreatic head mass compressing on CBD

87. Role of PET-CT IN TB

90. THANK YOU