Exam Revision Flashcards
What blood cell attacks parasited
eosinophils
what is a circulating macrophage
monocyte
what do NK cells do
virus and tumour destruction
red cell lifespan
120 days
neutrophil lifespan
7-8 hours
platelet lifespan
7-10 days
what are blasts
nucleated precursor cells
what cell are megakaryocytes the precursor of
platelets
what cell are reticulocytes the precursor of
red cell
what are myelocytes the precursor for
neutrophils
where is the first site of haemopoesis in the fetus
yolk sac
what other sites of haemopoesis are there in the fetus
liver by 6 weeks
then spleen by 12 weeks
where is the site of haemipoesis in the adult
bone marrow
what covers the endosteum
osteoclast and osteoblasts
what is the endosteum
the interface between bone and bone marrow
what type of marrow increases in elderly
yellow (fatty) marrow
what happens to the myeloid:erythroid ratio in haemolysis
it shows evidence of erytroid hyperplasia so it is reduced
what stimulates the maturation of erythroid precursors to become rbcs
erythropoietin
what tests are used to look at immature cells
immunophenotyping
cytochemistry
CD20
b cells
cells of myeloid lineage
rbcs platelets granulocytes macrophages dendritic cells
cells of lymphoid lineage
t cells
b cells
nk cells
dendritic cells
what is normal haematocrit
50 percent
what is koilonychia a sign of
iron deficiency
leg ulcers sign of
sickle cell
bone deformities a sign of
thalassaemia
glossitis a sign of
B12 deficiency
if there is reduced MCV this indicated
problem with haemoglobinisation
if there is large MCV indicated
problem with maturation
where does haemoglobin synthesis occur
cytoplasm
what anaemias result from decreased porphyrin
lead poisoning
sideroblastic anaemia
difference between blood components and blood products
blood components - one donor - red cells, plasma
blood products- many donors - albumin, Ig, anti d
how much of a therapeutic dose of platelets can you get from one donor
one quarter
what anticoagulant is used in donated blood
citrate based
how quickly must you obtain a blood donation sample
within 15 mins
what temp and for how long are red cells kept at
4 degrees
35 days
how long and at what temp are platelets stored at
22 degrees
shelf life five days
how long and at what temp is fresh frozen plasma kept at `
-30
up to two years
what type of antibodies are ABO
IgM
what chormosomes is our blood group on
chromosome 9
what type of antibodies are anti d and irregular antibodies
IgG
how soon must red cells be transfused once they have left the fridge
within 4 hours
after been out for 30 mins must transfuse or disguard
what process means that a therapeutic dose of platelets can be obtained from a single donor
apheresis
indications for fresh frozen plasma
bleeding
anti coagulant over dose
DIC
what three actions should you take in ABO incompatability reaction
Stop transfusion
give IV saline
Obtain bloods!
do not remove cannula
why is direct coombs test usually negative in ABO reactions
no intact red cell material
what is a delayed transfusion reaction usually due to
irregular antibodies
is direct coombs test positive in delayed transfusion reaction
yes
who do febrile no haemolytic transfusion reactions tend to occur in
people who are transfused more often
what mediated febrile non haemolytic transfusion reactions
HLA exposure in previous transfusion
anti bodies to contaminated white cells
what mediated urticarial reactions
IgE
what bacterial infections occur in red cells
pseudomonas
yersinella
what bacterial infection occur in platelets
staph, strep, salmonella
what virsus cannot be tested for in blood transfusion products
JC virus
what is the risk of HIV infection after a transfucsion
1 in 7 million
what two things occur in red cell destruction
reticulocytes
erytroif hyperplasia
what is the normal level of reticulocytes in blood
0.3-3 percent
what products are produced in extravascular haemolysis
normal products:
unconjugated bilirubinaemia
urobilinogenaemia
what products are produced in intravascular haemolysis
haemoglobinaemia
haemoglobinurea
haemosiderinuria
give examples of intravascular haemolyissi
ABO G6pD malaria pnh pch DIC
what is the function of haptoglobin
it mops up free Hb in blood
what happens to haptoglobin levels in haemolysis
decrease
which type of coombs test is used to test for haemolytic anaemias
coombs
how is hereditary spherocytosis inherited
autosomal dominant
how is G6PD deficiency inherited
x linked
what is the problem in G6PD
unable to reduce glutathione which is an antioxidant