Eat your vitamins Ileum!

Take Home Points: Vitamin & Elemental Absorption and Clinical Deficiency Syndromes
To know what deficiencies a patient may be at risk for, you have to know where each nutrient is absorbed.
Stomach – stomach acid cleaves protein-bound elements (B12, copper, Iron) and produces intrinsic factor (IF)
 -> Affected in: gastrectomy, Roux-en-Y, atrophic gastritis
 -> Deficiency Syndromes
  • B12 – megaloblastic anemia, peripheral neuropathy, impaired proprioception, slowed mentation
  • Copper – needed for WBC, RBC, and nervous system – results in anemia, usually microcytic (as Rabih pointed out, may help distinguish from B12 deficiency!), neutropenia, ataxia
  • Iron – anemia
Duodenum/Proximal jejunum – responsible for absorption of most water-soluble vitamins and elements
-> Affected in: Roux-en-Y and duodenal switch bypasses, Crohn’s affecting this area
-> Deficiency Syndromes
  • Thiamine – Beriberi, “dry” – aphonia, peripheral neuropathy, wernicke’s encephalopathy (nystagms, ophthalmoplegia, ataxia), confusion, coma, “wet” = neuro changes ­+ cardiomyopathy, cardiomegaly, CHF
  • Zinc – delayed growth, impotence, impaired wound healing, dysgeusia and loss of taste, skin lesions
  • Selenium – skeletal muscle dysfunction and cardiomyopathy
  • Copper –anemia, usually microcytic, neutropenia, ataxia
  • Iron – anemia  
Jejunum – absorption of fat AND the fat soluble vitamins ADEK
-> Affected in: Roux-en-Y and duodenal switch as well as fat malabsorptive states (Celiac, CF, pancreatic insufficiency, Crohn’s)
-> Deficiency Syndromes
  • A – xerophthalmia, night blindness
  • D – rickets, osteoporosis
  • E – spinocerebellar neuromyopathy, hemolytic anemia in infants
  • K – impaired coagulation
Ileum – notable for B12 and bile acid absorption
-> Affected in: ileal resections (>100cm) and ileal disease stats (Crohn’s, lymphoma, etc)
->Deficiency Syndromes
  • Bile acids – may lead to fat malabsorption and deficiency of Vit ADEK + watery diarrhea from bile salt wasting
  • B12 – megaloblastic anemia, peripheral neuropathy, impaired prorprioception, slowed mentation

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s