1. Vitamins

2. Vitamins
organic substances with key roles in certain metabolic pathways; they are required in small amounts in food because they are not synthesized in the body .
body stores is varied
vit12 and vitA need years to deplete stores
folate and thiamine need weeks deplete

3. Vitamins Vitamins are fat-soluble (vitamins A, D, E and K)
water-soluble (vitamins of the B complex group and vitamin C).

4. Thiamin (vitamin B1) Function
thiamin pyrophosphate (TPP), is an essential cofactor in carbohydrate metabolism.
1. Involved in the oxidative decarboxylation of acetyl CoA in mitochondria.
2 .In the Krebs cycle, is the key enzyme for the decarboxylation of α-ketoacid.
3. Has role in peripheral nerve conduction (unknown mech.)

5. Thiamin (vitamin B1) Source many foodstuffs cereals, legumes
pork, as well as beef meat.
Coffee ,tea, raw fish decrease the vitamin .
milled and polished rice have little vitB1

6. Thiamin (vitamin B1) Deficiency
1. Cells cannot metabolize glucose aerobically this likely to affect the nervous system .
2 .There is accumulation of pyruvic and lactic acids, which produce vasodilatation and increased cardiac output.

7. Thiamin (vitamin B1) Causes
1. poor dietary intake, in severe prolonged hyper -emesis gravidarum
3 . where the only food consumed is polished rice
2 . In chronic alcohol-dependent patients
4. Chronic illness as cancer

8. Thiamin (vitamin B1) Clinical feature
Body stores are small and signs of deficiency quickly develop with inadequate intake.
Non specific at early stage : anorexia, fatigue, irritability
Two clinical forms
Dry beriberi
Wet beriberi

9. Thiamin (vitamin B1) Dry beriberi 1. peripheral neuropathy:
Sensory and motor pain and parasthesia
2.Cerebral involvement :
Wernicke-encephalopathy
mental impairment
cerebellar ataxia
ophthalmoplegia
horizontal nystagmus

10. Thiamin (vitamin B1) Korsakoff syndrome : loss of new memory
confabulation
Wet beriberi
high output failure (3 months)
peripheral neuropathy

11. Thiamin (vitamin B1) Diagnosis
measurement of the circulating thiamin concentration
enzymatic assay of transketolase activity.

12. Thiamin (vitamin B1) Treatment
100 mg/d of thiamine given parenterally for 7 days, followed by 10 mg/d orally until complete recovery.
Cardiovascular and ophthalmoplegic manifestations improve within 24 h .Others gradually clear
Wernicke-Korsakoff syndrome may be permanent or persist for several months.
VitB1 must be replaced in alcoholic patient after feeding

13. Riboflavin (B2 )
Riboflavin is a flavoprotein that is a cofactor for many oxidative reactions in the cell for energy production.
Source
widely distributed all plant and animal sources
(main source) cereals, milk, dairy products (good source) legume, Meat , fish , egg

14. Riboflavin (B2 ) Deficiency causes almost is dietary with other VitB
Clinical manifestations
1. Mucocutaneous lesion
angular stomatitis or
cheilosis
red inflamed tongue
2. Seborrhoeic dermatitis
(face around the nose)
scrotum or vulva.

15. Riboflavin (B2 ) 3.Conjunctivitis with vascularization of the cornea .
4. Anemia
5. Personality changes
Diagnosis
serum or urinary level
Treatment
Riboflavin 10 mg daily, usually given as the vitamin B complex.

16. Niacin (B3) two chemical forms, nicotinic acid, nicotinamide Function
Many oxidative steps in the production of energy and in DNA repair
source
many foodstuffs: plants, meat and fish.
can be synthesized in humans from Eggs, milk contain tryptophan.

17. Niacin (B3) Causes of deficiency
1. Dietary deficiency (corn based diet)
2. In malabsorption (rare)
3. In Hartnup's disease. (Tryptophan renal, GIT. absorption defect)

18. Niacin (B3) 4. In alcohol-dependent patients
5. In the carcinoid syndrome( tryptophan is needed for serotonine).
6.Isoniazid therapy ( lead to a deficiency of vitamin B6, which is needed for the synthesis from tryptophan).

19. Niacin (B3) Clinical features
Pellagra : dermatitis , diarrhoea and dementia
1. early non specific symptoms anorexia, weakness, irritability
2. bright red glossitis and angular stomatitis

20. Niacin (B3) 3. Dermatitis Scaling pigmented skin rash
exposed to sunlight
(casal s necklace)
4. Diarrhea
proctitis
esophagitis
(non infective)
5. Dementia
milder cases cause depression.
severe cases cause hallucinations and acute psychosis

21. Niacin (B3)
Diagnosis
assesing the urinary excretion of the 2 pyridone and 2 methyl nicotinamide.
Treatment
Nicotinamide 300 mg daily by mouth with a maintenance dose of 50 mg daily
NB. VitB3 used in RX of hyperlipidemia

22. Vitamin B6
Vitamin B6 exists as pyridoxine, pyridoxal and pyridoxamine.
Function
cofactor of many enzymes involved in the metabolism of many amino acids.
neurotransmitters synthesis
heme synthesis.
Vitamine metabolism as niacin

23. Vitamin B6 Source is found widely in plant and animal foodstuffs.
Cause of deficiency
1. Dietary deficiency ( isolated extremely rare)
2. Some drugs
isoniazid
hydralazine
methyldopa
penicillamine

24. Vitamin B6
Clinical features 1. mucosal changes 2. The peripheral neuropathy personality changes depression, confusion 3. Microcytic hypochromic anaemia Treatment 100 mg daily should not be exceeded. NB. VitB6 used as antiemetic especially in the pregnancy

25. Vitamin B12
function
cofactor for activation of the folate (demethylation of methyl THF polyglutamate to THF).
Coenzyme for many synthetic reactions
Source
animal sources meat, fish, eggs and milk, but not in plants.
The storage may take 2 years or more after absorptive failure before deficiency develops.

26. Vitamin B12 Deficiency 1. Low dietary intake, Vegans
2. Impaired absorption
Stomach : Pernicious anaemia Gastrectomy
Congenital deficiency of intrinsic factor
Pancreatic insufficiency
Small bowel: ilea disease or resection Bacterial overgrowth Diphyllobothrium latum
3. Abnormal utilization Congenital transcobalamin II deficiency

27. Vitamin B12 Clinical features megaloblastic anemia
glossitis and angular stomatitis.
The neurological changes
polyneuropathy
subacute combined degeneration of the spinal cord
psychiatric problems
Dementia
optic atrophy

28. Vitamin B12 polyneuropathy
symmetrical paraesthesiae in the fingers and toes
subacute combined degeneration
( posterior, lateral columns of the spinal cord)
loss of vibration sense and proprioception
sensory ataxia
progressive weakness
Paraplegia may result.

29. Vitamin B12 psychiatric problems depression hallucinations Dementia
optic atrophy

30. Vitamin B12 Investigations Hematological findings
features of a megaloblastic anemia
2. Bone marrow
features of megaloblastic erythropoiesis (
3. Serum bilirubin may be raised
result of ineffective erythropoiesis.
4. Serum vitamin B12
below the normal (160 ng/L)

31. Vitamin B12
Treatment
Hydroxocobalamin 1000 μg can be given intramuscularly.
improvement of the polyneuropathy may occur over 6-12 months,
long-standing spinal cord damage is irreversible.

32. Folates in food as in reduced dihydrofolate or tetrahydrofolate (THF)
function
coenzymes in the transfer of single carbon units in amino acid metabolism and DNA synthesis.
Source
Dietary intake Folate is found in green vegetables
Cooking causes a loss of 60-90% of the folate.

33. Folates Causes of folate deficiency 1. Nutritional major cause
Poor intake
Old age
Poor social conditions
anorexia
Gastrointestinal disease
partial gastrectomy
small bowel disease as coeliac disease
Antifolate drugs
Anticonvulsants:
Phenytoin, barbiturates
Methotrexate, , trimethoprim, sulphasalazine

34. Folate 2. Excess utilization Physiological Pregnancy Lactation
Pathological
Haematological disease with excess red cell production, e.g. haemolysis
Malignant disease with increased cell turnover
Inflammatory disease
Haemodialysis or peritoneal dialysis (loss with the fluid)

35. Folate Clinical features asymptomatic
symptoms of anaemia or of the underlying cause.
Glossitis can occur.
CNS manifestations does not occur.
Investigations
The haematological findings are those of a megaloblastic anaemia .
low levels of serum folate (4-18 μg/L).

36. Folate Treatment of folate deficiency
5 mg of folic acid daily for about 4 months to replace body stores.
Rx of underlying cause, e.g. coeliac disease.
Prophylactic folic acid is recommended for all women planning a pregnancy. (neuronal tube defect)
Prophylactic folic acid is also given in chronic haematological disorders

37. Vitamin C (Ascorbic acid)
function
It is involved in the hydroxylation of proline to hydroxyproline, which is necessary for the formation of collagen.
Source
Vitamin C is present in all fresh fruit and vegetables.

38. Vitamin C (Ascorbic acid)
Deficiency
1. is seen mainly in the elderly and single people who do not eat vegetables.
2. Increase need in the trauma, burn infection
3. drugs as steroid, indomethacin, aspirin, tetracycline

39. Vitamin C Ascorbic acid
Clinical features : scurvy
Per follicular hemorrhages
Swollen, spongy gums with bleeding and superadded infection
Spontaneous hemorrhage (git, joint, peritoneum)
Failure of wound healing

40. Vitamin C Ascorbic acid
Diagnosis
Plasma ascorbic acid is very low (less than 11 μmol/L) .
Treatment
200 mg of ascorbic acid daily and encouraged to eat fresh fruit and vegetables.
NB. Vitc in large amount used in upper respiratory tract infection

41. Thanks