red blood cells and anaemia Flashcards
what hormone regulates erythropoiesis
erythropoietin (Epo)
where is the hormone erythropoietin found
90% in the kidney
where does red blood cell production start
in red bone marrow from stem cells, creating bursting forming units then colony forming units
what do red cells differentiate into when they eject their nuclei
reticulocytes
once differentiated what do reticulocytes digest
their organelles (Golgi)
what does a high reticulocyte count indicate
a high rate of new red blood cells are present (can occur after blood loss)
what is the transport molecule for iron in haemoglobin
transferrin
what is the advantages and disadvantages of red blood cells having an uncomplicated cell membrane
A - simple passage of oxygen
D - fragile so damage easily
what is the advantages and disadvantages of red blood cells having a lack of a nucleus and most cellular enzymes and organelles
A - flexibility to penetrate fine capillaries
D - cant make protective enzymes
what is the advantages and disadvantages of red blood cells having membranes that carry antigens
A - certain phenotypes confer resistance to malaria
D - incompatibility can trigger serious transfusion reactions
what is ferritin
an intracellular protein that stores iron.
what are some of the main symptoms of anaemia
dizziness, low BP, shortness of breath
main repercussions of anaemia
tiredness, (in children) decreased IQ, (in pregnancy) failure to breast feed
cardiovascular risk (myocardial infarction)
what are some of the main reasons for differences in symptom presentation
- Speed of onset (rapidly progressive produces more symptoms than slow )
- severity (mild doesn’t produce as many symptoms)
Age - (elderly more effected)
what factors make the oxygen disassociation curve to move to the right
physiological states where tissues require more oxygen such as during excersise
what does the oxygen disassociation curve moving to the right mean for the unloading of oxygen at target tissues
- makes it more difficult to bind to oxygen but makes it easier to unload to the tissues that require it
is foetal haemoglobin to the left or to the right of adult haemoglobin
to the left as it needs a to easily take up oxygen from adult haemoglobin
what is Haematocrit (HCT) a measurement of
the proportion of whole blood that is taken up by red blood cells
how is HCT calculated
(MCV x RBCC)/1000
what is Mean Cell Haemoglobin (MCH) a count of
the average Hb per red cell but does not consider its size.
how is MCH calculated
Hb/RBCC
what is Mean Cell Haemoglobin Concentration (MCHC) a measurement of
the average Hb per cell
taking into account MCV.
how is MCHC calculated
[Hb/(MCV x RBCC)] x 100
what can red blood cell distribution width indicate
can indicate a dual population of red
cells e.g. post transfusion, post treatment.
what is 1/2 classification of anaemia (and what are the main types within it )
size based
microcytic - small red blood cells
macrocytic - large red blood cells
normocytic - normal red blood cells
what is 2/2 classification of anaemia (and what are the main types within it )
variation based on colour
normochromic - normally stained red blood cells
hypochromic - less stained red blood cells
hyperchromic - more densely stained red blood cells
what does the biochemical test CRP (C reactive protein) indicate
gives indication to the level of inflammation so helps interpret ferritin levels
what are the 3 main biochemical tests for anaemia
-serum ferritin
- C reactive protein
- soluble transferrin receptors
why can drinking caffeine when eating cause anaemia
less iron is absorbed into the body
what are some treatments of hypochromic anaemia
correct diet, iron tablets
what is ferinject given for
rapid correction of iron levels before surgery
what happens if there is a lack of folate in the body
causes a lack of divisions in cells causing larger cells but fewer of them
what is the treatment for folate deficiency
correction of the diet
what is the treatment for pernicious anaemia
- either diet related correction
- or injections of hydroxocobalamin every 3 months
what are Haemoglobinopathies
are genetic (inherited) disorders of haemoglobin,
the oxygen-carrying protein of the red blood cells.
what are the 2 types of thalassaemia
alpha and beta
what are the treatment methods for beta thalassaemia
blood transfusions
iron chelation
prevention - antenatal haemoglobinopathy
screening & counselling
what is the three stage response to a haemorrhage
1 - hypovolemia and cardiovascular compensation
2 - transcapillary fluid redistribution and isovolemic anaemia
3 - renal fluid/ electrolyte conservation and haemopoiesis
