dums ppt Flashcards
life span of a red blood cell
120 days
life span of a neutrophil
7-8 hours
life span of a platelet
7-10 days
function of neutrophils
acute inflammation
what is this
neutrophil
what is this
eosinophils
function of eosinophils
allergy, parasites
what is this
basophil
function of basophils
IgE mediated reaction
what two types of stem cells does a blood stem cell produce
myeloid and lymphoid
what does a myeloid stem cell produce
-myeloblast
-erythrocyte
-megakaryocyte
what do myeloblasts produce
granulocytes
-basophil
-eosinophil
-neutrophil
what happens in hypoxia
Hypoxia sensed by the kidney, EPO produced by the kidneys, RBC production stimulated, EPO drops, repeat
what is the erythron
total mass of circulating RBC’s, their precursors and tissues that produce them
what does the spleen do
recycles old cells into iron, bilirubin and amino acids
what are the amino acids used for in erythropoiesis
to make globin
what does iron do in erythropoiesis
attached to heam
where is blood made in a foetus
-yolk sac til week 10
-liver from week 6
-spleen 3rd-7th month
-marrow starts week 16
where is blood made at birth
mostly bone marrow
-liver and spleen if needed
where is blood made in an adult
bone marrow in axial skeleton
what is the active form of marrow and why
red cause it contains blood stem cell whereas yellow is mostly fat
what is this
red pulp of spleen
what is this
white pulp of slpeenm
what is the red pulp in the spleen
-vascular sieve
-phagocytoses old RBC’s and breaks them into iron and bilirubin
white pulp in the spleen
immunological
-white cells
splenomegaly triad of symptoms
-dragging LUQ sensation
-discomfort eating
-pain
causes of increased spleen function
-haemolysis
-infection (mono)
-autoimmune disease
-extramedullary haematopoiesis
cause of increased blood flow into the spleen
portal hypertension
causes of hyposplenism
-splenectomy
-sickle cell disease
-coeliac disease
-sarcoidosis
-iatrogenic
what would hyposplenism cause to be seen on a blood film and why
abnormal red cells
-vascular sieve is lost
blood film after a splenectomy
howell-jolly bodies
target cells
how long should someone avoid contact sport for after EBV infection
2 months
-even if no splenomegaly
normal Hb
males >= 130
females >= 120
what is haemodilution
false anaemia caused by excess fluids
what does haematocrit measure
the proportion of RBCs in blood
if someone with anaemia doesn’t respond to iron treatment, which type of anaemia do they most likely have
sideroblastic
-as this type is an issue with attaching the iron to the haemoglobin not iron production
can you give someone who’s coeliac and has anaemia iron treatment
no
-because the issue is with iron absorption
where is iron absorbed
jejunum
what is seen on blood films in iron deficiency anaemia
-hypochromic cells (pale)
-small rbcs
-pencil poikilocytes
-target cells
what happens when iron is reduced in iron deficiency anaemia
iron/ferritin - low
transferrin - low
transferrin sats - low/normal
anaemia of chronic disease
iron/ferritin - low
transferrin - high
transferrin sats - low
iron deficiency
iron/ferritin - high
transferrin - high/normal
transferrin sats - high
iron overload
why are rbcs big in megaloblastic anaemia
impairment of DNA
-precursor cells fail to become smaller
-red cells have DNA impairment so increase in apoptosis leading to anaemia
where is folate absorbed
duodenum and jejunum
examples of increased demand for folate
-pregnancy
-haemolysis
-malignancy
-inflammatory disease
what drugs can cause folate deficiency
anti convulsants
what happens if you treat folate and B12 is low
will cause subacute degeneration of the spinal cord
where is B12 absorbed
terminal ileum
which drugs can cause B12 deficiency
PPI
when does IF bind to B12 and why
after the ampulla of Vater due to the change in pH brought about by pancreatic secretions
how can B12 deficiency cause neurological symptoms
because its involved in the production of the myelin sheath
what is the MCV in sickle cell anaemia
normal
is there reticulocytosis in sickle cell anaemia
yes
how long do sickle red blood cells live
10-12 days
-patient is in chronic haemolysis
chronic sickle cell anaemia issues
-sequestration in liver/spleen
-chronic haemolysis
-hyposplenism due to repeated infarcts = increased infection risk
what is aplastic anaemia
immune system attacking haemopoietic stem cells in marrow
causes of pancytopenia: decreased production
-inherited
-acquired 1 marrow failure
-acquired 2 marrow failure
causes of pancytopenia: increased destruction
hypersplenism
-slows transit of cells through spleen = more time to be broken down
what is compensated haemolysis
reticulocytosis and maintained Hb
what is decompensated haemolysis
present with signs, low Hb
what haemopoiesis for ALL
monoclonal
Auer rods
AML
