142: Clinical Features of Malabsorption Flashcards
AH minor updates
Where in the GI tract is iron absorbed?
Duodenum
Where in the GI tract are monosaccharides and amino acids absorbed?
Jejunum
How is protein malabsorption diagosed?
Clinical presentation: signs/symptoms related to underlying cause (eg portal hypertension), possibly Diarrhea, edema, ascites, reduced muscle mass/function
alpha-1-antitrypsin clearance (rarely done in practice)
Which part of the GI tract is most affected by Celiac disease?
Small intestine
Proximal (duodenum) more affected than distal
- => problems with iron absorption*
- => marked villous blunting and increased intraepithelial lymphocytes*
=> HLA DQ2, DQ8
Which enzyme is useful in diagnosis in pancreatic exocrine insufficiency?
Elastase
- Low fecal elastase is consistent with pancreatic insufficiency
- Not included in PERT, therefore can still be measured in pts receiving exogenous pancreatic enzymes
Describe the presentation of fat malabsorption
-
Steatorrhea
- Greasy, foul-smelling stools that float
- Stick to toilet bowl, difficult to flush
- Weight loss
- Nutrient deficiencies
- Fat soluble vitamins: ADEK
Where in the GI tract are lipids abosrbed?
Ileum
Which mineral deficiency is associated with celiac?
Why?
Iron deficiency
- Iron is absorbed in the duodenum
- Celiac disease often affects the duodenum more than other parts of the GI tract
What nutrients are abosrbed in the ileum?
- Lipids
- Fat soluble vitamins (ADEK)
- Folate
- Terminal ileum
- Vitamin B12
- Bile salts
In a patient with pancreatic exocrine insufficiency, what do you expect from their:
- Fecal fat levels:
- Fecal elastase levels:
(In general)
- Fecal fat levels: high
- Fecal elastase levels: low
Fecal elastase isn’t really an important enzyme, but useful diagnostically b/c not part of pancreatic enzyme replacement therapy
Where in the GI tract is vitamin B12 absorbed?
Terminal ileum
BUT, intrinsic factor necessary for B12 absorption is produced in the stomach
