Anaemias Flashcards
what is RBC a bag of?
enzymes
membranes
haemoglobin
whats the RBC membrane comprised of?
skeletal proteins that are responsible for maintaining RBC shape and deformability
what is the hereditary defect called in cell membrane?
hereditary spherocytosis
red cells spherical & removed from circulation
hereditary spherocytosis has defects in?
ankyrin alpha spectrin beta spectrin band 3 protein 4.2
hereditary spherocytosis presentation? (4)
anaemia
jaundice
splenomegaly
pigment gallstones
hereditary spherocytosis treatment?
folic acid
transfusion
splenectomy
why do a splenectomy?
as this is where RBC destroyed so they last longer but tried to avoid this
what can go wrong with the metabolic pathways of RBC?
glycolysis
pentose phosphate shunt (G6PD)
what is G6PD?
glucose 6 phosphate dehydrogenase
what does G6PD do?
protects red cell proteins from oxidative damage
how is G6PD linked?
X-linked
how does G6PD problem present?
anaemia
neonatal jaundice
splenomegaly
what can precipitate G6PD?
antimalarials
analgesics
anthelmintics
what is normal Hb A in adult haemoglobin?
Hb A: 97%
what happens to haemoglobin in Thalassaemia?
reduced or absent globin chain production
haemoglobin in sickle cell?
mutations leading to structurally abnormal globin chains
what is sickle haemoglobin composed of?
haem molecule and 2 a-chains and 2-b (sickle) chains
what does sickle cell lead to?
red cell injury cation loss dehydration haemolysis vaso-occlusion
how does sickle cell present?
painful vaso-occlusive crisis
stroke
infection
chest crisis
how to treat sickle cell?
hydration
O2
AVOID PETHIDINE
sickle cell management?
vaccine penicillin folic acid blood transfusion BM transplant
what is Thalassaemia?
reduced or absent globin chain production
what happens in b-thalassaemia major?
severe anaemia (3-6m age) expanded ineffective BM deformities splenomegaly growth retardation
life expectancy in b-thalassaemia major?
less than 1 year
treatment for b-thalassaemia major?
chronic transfusion support
when does death often happen in b-thalassaemia major?
2nd or 3rd decade due to heart/liver/endocrine failure
what can be used in b-thalassaemia major to increase life expectancy >40y?
iron chelation therapy
BM transplantation
normal Hg in males?
140-180
116-156 >70y
normal Hg in females?
120-160
108-143 >70
what can be seen on blood smears in sickle cell due to lack of spleen?
howell jolly bodies
