Updated: 1/21/2019

Malabsorption Syndrome

Topic
Review Topic
0
0
Evidence
2
0
0
Videos
1
Snap Shot
  • A 46-year-old female alcoholic with a long history of chronic pancreatitis presents with weight loss and a three-month history of frequent greasy stools. Physical exam shows pitting edema in the lower extremities, mild hepatomegaly, and scattered echymosis in the areas of trauma. An ultrasound of the pancreas shows calcifications. Endoscopic biopsy of multiple locations of the small bowel are normal.
Introduction
  • Malabsorption refers to 
    • ↑ fecal excretion of fat
    • concurrent deficiencies of fat soluble vitamins (A, D, E, and K), minerals, and proteins
  • Can be the result of
    • small bowel disease 
      • leading to decreased reabsorption of fat
        • due to ↓ absorbtive surface and ↓ lymphatic transport of absorbed fat
      • seen in Whipple's disease and abetalipoproteinemia
    • pancreatic insufficiency 
      • leading to improper breakdown of fats and proteins
        • due to the lack of lipases and trypsin
        • carbohydrate digestion is normal due to non-pancreatic sites producing amylases (e.g. salivary glands and brush border)
      • seen in cystic fibrosis, obstructing cancer, and chronic pancreatitis
    • bile salt deficiency 
      • leading to poor micellization of fat and absorption by the villi in the small intestine with lack of bile salt recycling
        • due to ↓ synthesis, ↓ transportation, and ↑ destruction
      • seen in cirrhosis, common bile duct stones, drug side effects (e.g. cholestyramine), Crohn's disease, and ileal resection
Presentation
  • Symptoms
    • hypovitaminosis symptoms
      • see Vitamins topic
    • steatorrhea
    • weight loss
    • weakness
  • Physical exam
    • pitting edema
      • result of hypoalbuminemia causing a ↓ plasma oncotic pressure
    • hepatomegaly
      • result of hypoproteinemia causing ↓ synthesis of apolipoproteins
        • necessary to surround the lipid VLDL before it is excreted into the blood
      • therefore may form due to fatty change
Evaluation
  • Quantitative stool fat test
    • >7 g/day is (+)
  • D-xylose absorption test
    • differentiates small bowel disease from pancreatic disease and bile salt deficiency
    • an oral form is given which does not need pancreatic enzymes to be broken down
    • if levels continue to be low then it is not being absorbed due to small bowel disease
  • Radioactive bile breath test 
    • used to rule out bile salt deficiency from bacterial overgrowth
 
 

Please rate topic.

Average 5.0 of 2 Ratings

Thank you for rating! Please vote below and help us build the most advanced adaptive learning platform in medicine

The complexity of this topic is appropriate for?
How important is this topic for board examinations?
How important is this topic for clinical practice?
ARTICLES (2)
VIDEOS (1)
Topic COMMENTS (8)
Private Note