Lower GI Tract - Part One
NFSC 370 - Clinical Nutrition
McCafferty
The Intestine
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“The” organ of digestion and absorption
Physical barrier against organisms
Contains numerous immune cells
Principles of Nutritional Care
Review:
 Fiber/Roughage
 high-fiber diet:
 low-fiber diet:
 Residue: fecal matter left after D&A of food and
bacterial fermentation
 bacteria
 water
 fiber
 mucosal cells
 mucus
 unabsorbed starches, sugars, protein, and minerals
 Low-residue diet
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Patients w/diarrhea, maldigestion, malabsorption
Minimizes foods that leave fecal residue
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Minimizes foods that increase GI secretions
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 Constipation
Fewer than 3 stools/week while on high residue diet
 More than 3 days without passage of stool
 Low stool volume/incomplete evacuation
Treatment:
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 Diarrhea
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Frequent evacuation of liquid stools
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Intractable diarrhea:
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Loss of fluid and electrolytes
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Symptom of disease state
Treatment
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If osmotic diarrhea:
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BRAT diet
 Steatorrhea
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Fat malabsorptionfatty diarrhea
Fat losses of up to 60g/day
Fecal fat test
Loss of fat in stool 
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 Treating Fat Malabsorption/Steatorrhea
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Fat-restricted diets:
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MCTs: C6-C12 FAs
• Do not require pancreatic lipase or bile for D&A
• Don’t form micelles -- absorbed directly into
portal vein rather than the lymphatic system
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Water-Miscible Fat-Soluble Vitamins:
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Oxalate-Restricted diets:
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Enzyme Replacement Therapy:
• When malabsorption is related to severe pancreatic
insufficiency or when steatorrhea is severe.
• Made from extracts of pork or beef pancreatic
enzymes.
Diseases of the Small Intestine
Celiac Disease
(Gluten-Sensitive Enteropathy)
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Causes flattening of the intestinal villi and
maldigestion/malabsorption.
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Requires strict adherence to the diet.
 Substitutes:
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Continuous adherence necessary, even if
consuming gliadin does not precipitate
symptoms.
Lactose Intolerance
 Causes
 Treatment
Inflammatory Bowel Diseases:
Crohn’s Disease &Ulcerative Colitis
 Both cause mucosal inflammation and
lesions.
 Etiology:
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linked to gene which causes faulty response to
microbes in the stomach
recall: GI tract = major immune system organ
may somehow trigger the immune system to
attack the intestinal lining
Crohn’s Disease:
 Inflammation and ulceration along the
length of the GI tract, often with
granulomas
 Most often affects ileum and colon, but can
occur anywhere along the GI tract.
 Can affect liver kidneys, joints, eyes, and
skin.
 No medical cure
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 Fistulas may develop
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 Inflammatory tissue changes are chronic.
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 most common between ages of 20-40
 symptoms:
 Bleeding can  anemia, secretions can cause loss of
proteins (albumin).
 Growth failure in kids is common.
 Deficiencies cause decreased immune fx.
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Ulcerative Colitis
 Usually confined to colon and rectum
 Inflammatory tissue changes are acute and
limited to mucosa and submucosal tissue
layers of the intestine
 age of onset: 15-30 and 50-60 yrs – more
common later in life
 Symptoms:
Nutrition Therapy for
Inflammatory Bowel Disease
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 Idea of “bowel rest” with TPN
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may be necessary in severe cases/fistula/obstruction
Nutrition Therapy for
Inflammatory Bowel Disease
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Small, frequent meals
Low-residue
 lactose if intolerant
Low fat w/ MCT oil if fat malabsorption present
Energy:
Protein:
MVI, Fe, Zn, vit. C, folate, B12, and fat-sol
vitamins
Drug Therapy
 Corticosteroids are effective at inducing
remission (prednisone)
 Anti-inflammatory agents
(aminosalicylates)
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Antidiarrheal (loperamide - “Lomotil”)
Antibiotics (sulfasalazine)
Immunosuppressants (cyclosporine)
May require bowel resection
Healed Crohn's