haematology intro Flashcards
what are the main 3 functions of blood
transports(e.g. hormones, nutrients)
regulation (pH buffers, temperature)
protection (clotting, antibodies )
what are the main physical properties of blood
-denser than water
-38*c and slightly alkaline
-bright red when saturated with oxygen, dark red when unsaturated
-sampled by venepuncture with a torniquet
what is haemopoiesis
the formation of blood cells
what type of feedback controls red blood cells count and platelet number
negative
what is the colour difference between new born bone marrow and adult bone marrow
new born is red and adult is yellow
what changes does acute leukaemia do to the bone marrow under the microscope
the marrow is filled with large leukemic blasts
- the cells are all immature and similar
what changes does aplastic bone marrow do to the bone marrow under the microscope
in severe cases its profoundly hypocellular
- with lots of gas present
what 2 subtypes of stem cells are produced by pluripotent stem cells
Myeloid stem cells & lymphoid stem cells
what are Myeloid stem cells and where do they develop
they develop in red bone marrow
- they give rise to platelets, monocytes and basophils
what are lymphoid stem cells and where do they develop
develop on red bone marrow
- they traverse and end in lymphatic tissues where they give rise to lymphocytes
what is the lymphatic system
a network of small vessels which carry lymph
what is lymph fluid and what’s its role in the body
- carry waste products around the body
- caries cells that are part of the immune system
- lymph vessels take fluid to lymph nodes
what do some myeloid cells differentiate into
progenitor cells
what do some precursor cells differentiate into
precursor cells
can Progenitor cells reproduce
no
what are Progenitor cells designated cell type that they form into
(CFU eg CFU-E)
what do precursor cells develop into
the formed elements of the blood like red bull cells
what are the main medical used of haemopoietic growth factors
- Recombinant growth factors
- Erythropoietin for kidney disease
- Granulocyte CSF for WBC
formation after chemotherapy - Thrombopoietin for chemotherapy
- Also used for clotting disorders & a
range of neonatal disorders
what is the other name of red blood cells
erythrocytes
how many red blood cells are produced every second
2 million
how many red blood cells are found on average in 1ml of blood
5 million
what is the role of basophils
they release heparin, histamine and serotonin
what is the role of eosinophils
they release histaminase
what are the 6 main types of white blood cells
mast cells, macrophages, monocytes, neutrophils , basophils, eosinophils
what are the characteristics of mast cells
- dilates blood cells and induces inflammation through the release of histamines
- recruits macrophages and neutrophils
what are the characteristics of macrophages
- phagocytic cell that consumes pathogens
- stimulates the response of other immune cells
what are the characteristics of monocytes
- differentiates into macrophages and dendritic cells in response to inflammation
what are the characteristics of neutrophils
releases toxins to kill bacteria
- also recruits other immune cells to the site of infection
what are the characteristics of basophils
responsible for the defence against parasites
- releases histamines that cause inflamation
what are the characteristics of eosinophils
releases toxins that kill bacteria and parasites but also causes tissue damage
what is a platelets lifespan
5-9 days
what are platelets
Small anucleate parts of cells required for haemostasis
what happens in blood vessels when an injury occurs
1- vascular spasm (arteries constrict to reduce blood flow)
2- platelet plug formation
3- blood clotting
why are different stoppers used when obtaining a blood sample
- as the blood will be used for different tests so will be needed for different things
- such as one stopper will stop the blood from clotting by removing the calcium from the blood
what are the 6 main blood tests
full blood count, erythrocyte sedimentation rate, coagulation screen, haematinic assays, immunophenotyping, genetic techniques
what abnormalities could be found in red blood cell count numbers
fewer red blood cells - indicates anaemia
too many red blood cells - indicates polycythaemia
what abnormalities could be found in red blood cell shape (known as poikilocytosis)
elliptocytes - elongated cells
schistocytes - tear drop shaped cells
what abnormalities could be found in red blood cell size (known as anisocytosis)
Normocyte - normal size
Macrocyte - larger than average
Microcyte - smaller than average
what does morphology mean in terms of blood film
refers to the examination of size shape and appearance of blood cells
what abnormalities could be found in red blood cell colour
polychromasia - if cells are a different colour
hypochromia - if cells are paler than normal (they contain less haemoglobin)
hyper chromia - if cells are darker than normal (caused by an excess of haemoglobin)
what is hypochromia and how is it caused
if cells are paler than normal (they contain less haemoglobin)
what is hyper chromia
if cells are darker than normal (caused by an excess of haemoglobin)
what does ‘philia’ mean
increase in number
what does ‘penia’ mean
decrease in number
what does pancytopenia mean
a lack of all cells
what does neutropenia mean
a lack of neutrophils
what does Eosinophilia mean
an increase in eosinophils
