Anaemia Flashcards
What does PCV stand for? What else is it known as? What does it mean?
Packed cell volume
Haemocrit
Volume percentage of RBCs in blood.
What Is normal haemocrit/PCV in:
Men?
Women?
45% men
40% women
What are the 3 most common symptoms of anaemia?
Fatigue, faintness, breathlessness
What 2 symptoms can people experience when anaemia exists alongside atheromatous arterial disease?
Angina pectoris
Intermittent claudication
What are normal Hb levels for:
Males?
Females?
Males: 13.5 - 17.5
Females: 11.5 - 16
What does MCV stand for? What is it?
Mean corpuscular volume
- the mean red blood cell size
Why does microcytosis come about? How does it appear on a blood film?
Decreased Hb content within the RBC
Hypochromic
What are the 4 main causes of microcytic anaemia?
Iron deficiency
Anaemia of chronic disease
Thalassaemia
Sideroblastic anaemia
Why is iron related to anaemia?
It is necessary for the formation of haem
How much iron is absorbed from the diet?
10%
Where in the GI tract is iron absorbed?
Duodenum
Name 3 factors that increase intestinal iron absorption?
Gastric acid
Iron deficiency
Increased erythropoietic activity
Where is non haem iron found in the diet? (2)
Vegetables
Fortified cereals
Where is haem iron found?
Derived from haemoglobin and myoglobin in red or organ meats
Of haem and non-haem iron, which is better absorbed?
Haem iron
How is iron transported in the blood?
Transferrin
Where is transferrin synthesised?
Liver
How is the body’s iron incorporated into haemoglobin
In developing erythroid precursors and mature red cells
How is body irod stored?
As ferritin and haemosiderin in hepatocytes, skeletal muscle and reticuloendothelial macrophages
What are the 4 main reasons for iron deficiency?
Blood loss (most common) - e.g. menorrhagia or GI bleeding
Incr demands - eg. growth and pregnancy
Decreased absorption - eg. small bowl disease or post gastroctomy
Poor intake
What is the most common cause of iron deficiency worldwide?
Hookworm = intestinal blood loss
What are normal MCV values?
80 - 96
What does MCH stand for? What is it?
Mean corpuscular haemoglobin
Average mass of haemoglobin per RBC
What do ferritin levels represent?
Iron stores
When might ferritin levels be normal despite the presence of iron deficiency?
Inflammatory or malignant disease, it is an acute phase reactant
What will the total iron-binding capacity be in iron deficiency?
High
How do you work out transferrin saturation?
Serum iron/TIBC
What is the transferrin saturation in iron deficiency anaemia?
<19%
In anaemia of chronic disease:
- What happens to the serum iron-binding capacity?
- What is the MCV?
- What is the MCH?
- Serum ferritin levels?
- Low
- Normocytic or microcytic
- Normochromic
- Normal or increased (NB - acute phase reactant)
Name 5 chronic conditions in which anaemia might occur
Crohn's RA (chronic infections): TB Malignancy Chronic kidney disease
Why does sideroblastic anaemia come about?
There is impaired utilisation of iron delivered to developing erythroblasts
What is sideroblastic anaemia characterised by? (3)
- refractory anaemia
- hypochroic cells in peripheral blood
- ring sideroblasts in the BM
Sideroblastic anaemia may be inherited, alternatively it may be acquired - how? (4)
Myelodysplasia (ineffective production of blood cells)
Alcohol excess
Lead toxicity
Isoniazid
What is the first investigation to order in macrocytotic anaemia.
Serum B12 measurement and red cell folate
What are the 2 subdivisions of macrocytic anaemia? How is it determined?
Megaloblastic
Non-megaloblastic
Examination of the bone marrow
What do lymphoid stem cells give rise to?
Pre T cells (which become T suppressor, T helper, NK cells)
Pre B cells (which become B cells and plasma cells)