Vitamins

Question 1

What are the fat soluble vitamins?

Answer 1

A, D, E + K

Question 2

Vitamin A

1. What does it do?
2. What clinical feature will be seen on deficiency?

Answer 2

1. • antioxidant
   • converted into retinal: am important visual pigment
2. night blindness

Question 3

Vitamin B1 (thiamine)

1. What is it important for?
2. What can cause its deficiency?
3. What conditions can be seen as side effect of thiamine deficiency?
4. When are oral thiamine supplements recommended?

Answer 3

1. catabolism of sugars and amino acids
   - > therefore consequences seen in highly aerobic tissues
2. • alcohol excess
   • malnutrition

3.

• wet beriberi: dilated cardiomyopathy
• wernicke’s: ataxia, ophthalmoplegia, nystagmus
• korsakoff’s: amnesia, confabulation
• dry beriberi: peripheral neuropathy

WKD - caused by drinking too much WKD

4. only in patients with chronic alcoholism

Question 4

Vitamin B3 (niacin)

1. What can cause it?
2. What clinical features will be seen in deficiency?

Answer 4

1. • Hartnup’s disease: hereditary disorder reducing the absorption of tryptophan
   • Carcinoid syndrome: increased tryptophan metabolism to serotonin
2. pellagra: dermatitis, diarrhoea, dementia

3Ds for B3 deficiency

Question 5

Vitamin B6 (pyridoxine)

1. What can cause it?
2. What features are seen in deficiency?

Answer 5

1. isoniazid
2. • peripheral neuropathy
   • sideroblastic anaemia (disorder of bone marrow where produces sideroblast instead of normal RBCs)

Question 6

Vitamin C

1. What are its functions?
2. What clinical features are seen in deficiency (scurvy)

Answer 6

1. • antioxidant
   • facilitates iron absorption
   • cofactor in norepinephrine synthesis
   • collagen synthesis
2. • easy bruising
   • poor wound healing
   • gingivitis with bleeding + receding gums
   • Sjogren’s syndrome
     arthralgia
   • oedema