MEH haemotology Flashcards
cause of pernicious anaemia?
Auto-antibodies interfering with the production or function of intrinsic factor
> essential for the absorption of vitamin B12
“Pernicious” means “deadly”
role of ferroportin
ferroportin transports it out of the erythrocytes across the basolateral membrane of the enterocytes and into the bloodstream.
role of hepcidin
inhibits iron transport by binding to ferroportin
> prevents iron from being exported into the bloodstream thereby reducing dietary iron absorption.
what facilitates uptake of ferrous iron (Fe2+) from the intestinal lumen into enterocytes?
Divalent metal transporter 1 (DMT1)
intracellular protein-iron complexes that are used to store iron?
Ferritin and haemosiderin
treatment option for a patient with severe hereditary haemochromatosis?
Therapeutic phlebotomy to remove excess iron
what is haemoglobin H disease?
type of alpha- thalassemia
reduced formation of alpha globin chains.
imbalance of global chains needed to form haemoglobin
- see skeletal abnormalities as RBCs are created in unusual places e.g. bone cortex and impair growth
effect of chronic haemolysis?
XS bilirubin >gall stone formation
Microangiopathic haemolytic anaemia?
type of anaemia that can result from red blood cells becoming damaged by the shear stress produced by a defective heart valve
role of janus kinase 2 receptor?
stimulate signalling pathways leading to erythrocyte production in response to the hormone erythropoietin.
megakaryocytes?
the cells that platelets (thrombocytes) ‘bud off’ from
what is primary myelofibrosis?
myeloproliferative neoplasm- proliferation of mutated hematopoietic stem cells results in reactive bone marrow fibrosis eventually leading to the replacement of marrow with scar tissue
> extra medullary haemopoesis occurs (haemopoesis outside of bone marrow e.g liver > enlarged liver
what is the name given to small red spots under the skin from broken capillaries?
Petechiae.
- seen in thrombocytopenia
(less than 3mm)- purpra over 3mm
what would cause an inc in hepcidin hormone?
cytokines- ACD/ inflammation
cause or normocytic anaemia?
chronic kidney disease
effect of urea on erythropoiesis?
increase in urea concentration in blood:
inhibit erythropoiesis
reduces the lifespan of existing red blood cells
inhibits platelet function
> can cause chronic bleeding from GI
what is Felty syndrome?
triad of symptoms
- Rheumatoid arthritis
- splenomegaly
- neutropenia (low)
what is a Leucoerythroblastic film
Blood film where Granulocyte precursors and nucleated RBCs are present
effects of XS iron?
cirrhosis, cardiomyopathy, diabetes mellitus, skin pigmentation, polyarthropathy hypogonadotrophic hypogonadism.
Which vitamin is involved in the synthesis of clotting factors?
Vit K
which condition show a red blood cell mean cell volume (MCV) lower than the normal range?
Iron deficiency anaemia
which conditions show a red blood cell mean cell volume (MCV) greater than the normal range?
Alcoholism
Liver disease
Haemolytic anaemia
Megaloblastic anaemia
term meaning increased variation in the size of red blood cells?
Anisocytosis
Define : Poikilocytosis Eliptocytosis Spherocytosis Anisocytosis Hypochromic
Poikilocytosis-abnormally shaped RBCs
Eliptocytosis- elliptical RBCs
Spherocytosis-spherical RBCs
Anisocytosis-increased variation in the size of RBCs
Hypochromic- RBCs that are paler than normal (due to less haemoglobin)
what is haematocrit?
volume percentage of red blood cells in blood
divide this (haematocrit) by the concentration of RBCs to get the mean corpuscular volume
which thalassemia is a cause of severe anaemia?
‘β-thalassaemia intermedia’
