Microcytic Anaemia Flashcards
Microcytic anaemia is caused by a defect where? This leads to problems with what?
The cytoplasm / Hb synthesis
An anaemia caused by deficient Hb synthesis could be described as what?
A microcytic, hypochromic anaemia
To make Hb, what do you need?
Globins and haem (formed of iron Fe2+ and porphyrin ring)
What are some generic causes of haem deficiency which could lead to a microcytic anaemia?
Reduced iron for erythropoiesis, problems with porphyrin synthesis
What are some causes of a lack of iron?
Iron deficiency due to low body iron or anaemia of chronic disease leading to lack of available iron
What are some causes of a lack of porphyrin synthesis?
Lead poisoning or pyridoxine responsive anaemias
What is a rare condition which causes haem deficiency which can lead to a microcytic anaemia?
Congenital sideroblastic anaemia
What is the main cause of globin deficiency?
Thalassaemia
To have a microcytic anaemia, there must be a deficiency of one of what two things?
Haem or globin
What is the most common cause of microcytic anaemia?
Iron deficiency
The vast majority of the iron in the body is found within where?
Haemoglobin
Describe the sequential consequences of a negative iron balance?
Exhaustion of iron stores leads to iron deficient erythropoiesis and a falling MCV causing microcytic anaemia.
Over time, iron deficiency can cause epithelial changes in the skin - what is an example?
Koilonychia
Iron deficiency can be confirmed as a diagnosis by what results?
Anaemia (low Hb) and reduced storage iron (low serum ferritin)
What are the 3 major causes of iron deficiency?
Not consuming enough to meet physiological requirements, losing too much or not absorbing enough iron
Relative deficiency of iron due to insufficient intake of iron can be seen in who? Why?
Women of child bearing age and children / they have increased demands for iron
Absolute deficiency of iron due to insufficient intake of iron can be seen in who?
Vegetarians
What are the 3 main ways people lose iron through blood loss?
Menorrhagia, GI blood loss and haematuria
If there is iron deficiency in a man or a post-menopausal women, what should you always consider as the cause?
GI bleed from a tumour, ulcer or NSAID overuse
What is the main cause of not enough iron being absorbed?
Coeliac disease
If a man is iron deficient, what should you always assume?
That it is pathological and not a dietary problem
