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Diffuse Small Bowel Disease
Click on Blue Links for Imaging Examples
Sprue
• 3 diseases:
Celiac Disease of Children, Nontropical sprue and Tropical Sprue
• Celiac disease and Nontropical sprue improve on gluten-free diet
• Tropical sprue improves with antibiotics and folic acid
Imaging
• The hallmark
features are: dilatation and dilution, especially in jejunum
• Segmentation of the barium column occurs because it moves more
slowly through areas of excessive fluid and separates from the rest of the
column-not commonly seen with newer barium mixtures
• Fragmentation is an exaggerated example of the irregular
stippling of residual barium in the proximal bowel (which is normal)
• Intussusception is not uncommon but is usually
not obstructive; sprue has increased risk of
ca and lymphoma
• Moulage sign is caused by
dilated loop with effaced folds looking like tube into which wax has been
poured
Scleroderma
• Affects
esophagus, small bowel and colon, sparing the stomach
• Atrophy of the
muscular layers and replacement with fibrous tissue
• Associated with malabsorption
Imaging
• Whole small bowel
is usually dilated with close approximation of the valvulae (hide-bound appearance)
(stack-of-coins)
• Does not have
increased secretions as does sprue
• May be associated
with pneumatosis intestinalis
Whipple’s
Disease
• Glycoprotein in the lamina propria of the small bowel is Sudan-negative,
PAS-positive
• Clinically: arthralgia, abdominal pain, diarrhea and
weight loss
• Treated with long
term antibiotics-penicillin
• Very rare
Imaging
• The hallmarks of
the disease are nodules and a markedly thickened bowel wall (picket-fence)
• Small bowel may or
may not be dilated
• Affects jejunum
mostly
Amyloidosis
• GI involvement is
common
• Associated with malabsorption
Imaging
• Marked thickening of the valvulae (picket-fence)
• No dilatation or
dilution
• Affects entire
small bowel
Hypoproteinemia
• Hypoalbuminemia resulting from liver or kidney
disease lower than 1.5 grams per cent
• Usually
asymptomatic from intestinal edema itself
Imaging
• Changes are
present throughout small bowel
• Loops are
separated due to edema of walls
• Folds are quite
thick (picket-fence)
Giardiasis
• Giardia lamblia is
a flagellated protozoan, a normal parasite of the small bowel
• Clinically:
diarrhea and malabsorption
• Treated with metronidazole (Flagyl)
• Some patients have hypogammaglobulinemia and nodular lymphoid
hyperplasia associated with giardiasis
Imaging
• Usually limited to
duodenum and jejunum
• Thickening of
the folds
• Marked spasm
and irritability of the bowel
• Increased
secretions is common
Ischemic
Bowel Disease
• Thickening of the
wall due to edema and hemorrhage
• Localized
perforations can produce air in the bowel wall or in portal venous system
Imaging
• Spasm and
irritability early is replaced by an atonic bowel later
• Lumen is narrowed
• Folds are
thickened, sometimes producing “thumb-printing”
• Healing may result
in stricture formation
Intramural
Bleeding
• Suggested if
there is duodenal obstruction following trauma
• Localized lesions
occur with trauma
• Diffuse lesions
are seen with anticoagulants
Imaging
• Uniform, regular,
thickening of the folds
• Separation of the
loops
• Mass effect
• No spasm
Radiation
Enteritis
• Changes are
identical to ischemia since radiation changes
are actually secondary to an arteritis with occlusion of small vessels
• Localized to area
of radiation portal, especially pelvis in female 2° endometrial carcinoma treatment
• Previous adhesions
from surgery may anchor small bowel in pelvic portal and predispose to XRT
changes
• Mucosa is most
sensitive to radiation
Imaging
• Localized
thickening of the folds 2° edema and hemorrhage
• May result in
strictures later in course
Lymphoma
• Most commonly
involves terminal ileum
• Bowel wall becomes
markedly thickened and submucosa infiltrated
(picket-fence)
• “Thumb-printing“
may be seen
• Loops are widely
separated and there may be mass effect
• Another form may
have a large ulceration which is confined and produces so called “aneurysmal dilatation” of the bowel
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