2. The anaemias Flashcards
What are the main distinguishing features of an iron-deficient red cell?
Small with not much haemoglobin in them. (microcytic and hypochromic)
Why are the red cells microcytic?
Lack of iron impairs red cell synthesis
Sources of dietary iron
Red meat, fish and fortified foods.
There are other sources see list
Egg yolk
Wholemeal bread
Breakfast cereals
Vegetables and pulses
Nuts and prunes
Fortified foods
Reasons for increased iron requirements
Excess utilization, chronic blood loss, poor diet
What does serum ferritin measure?
Iron stores
By what processes does a red cell produce its energy?
Has to generate energy as ATP via the Embden-Meyerhof pathway
Generate reducing power as NADPH via the Hexose-monophosphate pathway
Where in the body is iron absorbed?
Small intestine
What is anaemia of chronic disorder?
A form of anaemia seen in or associated with chronic illness
Clinical features of iron deficiency anaemia
Pallor
Sore mouth
Brittle nails
Dysphagia
Glossitis
Abnormal appetite
Hair thinning
Lassitude
Fatigue
Tachycardia
What does a Prussian blue stain demonstrate?
Iron stores in tissue such as bone marrow and liver
Why is folate deficiency common in pregnancy?
Excess utilization of folate in pregnancy causes depletion of folic acid stores.The bodies store of folic acid will only last 3 months
Why does the plasma level of homocysteine rise in B12 deficiency?
B12 is a coenzyme for 2 biochemical reactions on of which is methylation of homocysteine to methionine. Without B12 homocysteine levels build up in the body.
Why does B12 deficiency cause neurological changes?
B12 is involved in myelin production. Myelin protects the nerve cells. B12 deficiency causes progressive damage to sensory nerves
Where is B12 absorbed?
Ileum
What is intrinsic factor?
Intrinsic factor is a glycoprotein produced by the parietal cells of the stomach. It is necessary for the absorption of vitamin B12
