Flashcards in Nutrition Deficiencies Deck (83)
Vitamin C Function
- Facilitates iron absorption (reduces to Fe2+)
- Hydroxylation of proline and lysine in collagen synthesis
- Necessary for DA beta-hydroxylase (converts DA to NE)
What can Vit C treat?
- Ancillary treatment for methemoglobinemia
Vit C deficiency?
Scurvy - swollen gums, bruising, petechiae, hemarthrosis, anemia, poor wound healing, perifollicular and subperiosteal hemorrhages, "corkscrew hair
- Weakened immune resopnse
- Fe-deficient anemia
Vit C excess?
N/v, diarrhea, fatigue
- Calcium oxalate nephrolithiasis
- Increased risk of iron toxicity in predisposed (transfusions, hereditary hemochromatosis)
- Milk, sun (stratum basale)
Storage form (measured in serum)
Calcitriol - Active form
- PTH regulation
Vit D Function
- Increased intestinal absorption of calcium and phosphate
- Increased bone mineralization at low levels
- Increased bone resorption at higher levels
Vit D Deficiency
Rickets (children), osteomalacia (adults)
- Hypocalcemic tetany
Who needs Vit D supplement?
Exclusively breastfed infants
What exacerbates Vit D deficiency?
Low sun exposure, pigmented skin, prematurity
What causes Vit D deficiency?
Low sunlight, malabsorption, liver/renal DZ, elderly
Vit D Excess
- Hypercalcemia, hypercalcuria, loss of appetite, stupor
When is Vit D excess seen?
Increased activation of Vit D by epithelioid macrophages
Antioxidant (protects RBCs and membranes from free radical damage)
Vit E Deficiency
Hemolytic anemia, acanthocytosis, muscle weakness
What part of the spinal cord is affected in Vit E deficiency?
- Posterior column and spinocerebellar tract demyelination
- Neuro presentation similar to B12 deficiency but no megaloblastic anemia, hypersegmented PMNs, or increased serum methylmalonic acid
Cofactor for gamma-carboxylation of glutamic acid residues on various proteins required for blood clotting
Where is Vit K synthesized?
Who gets vit K deficient?
- Neonates (sterile intestines) - increased PT and PTT, normal BT - given Vit K injection at birth
- Prolonged broad-spectrum ABx (kill gut bacteria)
Vit K antagonist?