haemolytic anaemia Flashcards
intarvascular vs extravascular haemolysis causes
extravascular within reticuloendothelial system particularly spleen (autoimmune, alloimmune, hereditary spherocytosis)
intarvascular within vasculature examples: malaria, G6PD deficiency (malaria protective) . mismatch antibodies in transfusion, Cold agglutanins. drugs:dapsone dermatitis herpetiformis treatment in coeliacs), MAHA DIC, TTP, HUS HELLP me. Paroxysmal nocturnal Haemoglobinuria (haemoglobinuria and elevation of plasma lactate dehydrogenase due to rbc memebrane protein defiency, treat with eculizumab a complement antibody)
what is the stain
pearl (prussian blue) stain for haemosiderin, increase iron in liver biopsy (parenchyma and kupffer cells), seen in pyruvate kinsae deficiency, haemochromatosis
haemolytic anaemia increases reticulocytes except?
parvovirus b19, bone marrow suppression at early stage of maturation
haptoglobin levels in haemolytic anaemia ?
decrease haptoglobin in plasma as it binds Hb released by haemolysis of RBC
other features of haemolytic anaemia, anaemia increased reticuloyctes, hyperbillirubinaemia, increased LDH (glycolytic enzyme), haemoglobinuria, haemosiderinuria, polychromasia (dye taken up by reticulocytes)
test for spherocytosis
osmotic fragility test,increased sensitivity to lysis in hypotonic saline, eosin 5 maleimide dye.
hereditary spherocytosis blood film
dense stain
spherocytes
hyperchromic cells (no central pallor)
polychromatic (immature)
MCHC increased
howell jolly bodies
eosin 5 malemide
Hereditary elliptocyotisis vs Hereditary Pyropoikilocytosis
heterozygous elliptocytosis, blood count normal no polychromasia no significant haemolysis
pyropoikilocytosis is autosomal dominant
budding of rbc membrane on film
marked pokilocytosis and requires exchange transfusion
what is the function G6PD
enzyme in first step of pentose phosphate pathway generates NADPH to maintain intracellular glutathione (GSH) protects cells from oxidative stress. x-linked condition
neonatal jaundice, most common cause of kernicterus, acute haemolysis triggered by drugs fava beans. also chronic haemolytic anaemia
pyruvate kinase deficiency blood film
most common glycolysis pathway defieincy
echinocytes projections from rbcs
during dehydration RBC’s more spherical
echinocytes increase post splenectomy
what condition do you get basophillic stippling
pyrimidine 5 nucelotidase deficiency. pyrimidine nucleotides are toxic to rbc. stippling is basophilic granules dispersed through cytoplas of erythrocytes in smear. also seen in lead poisoning which inhibits the enzyme.
main investigations for haemolytic anaemia
thick and thin blood film : malaria
direct antiglobulin test : presence of Ig on RBC (AIHA)
urinary haemosiderin/haemoglobin : caused by intravascular haemolysis (LDH increase, haptoglobin decrease)
osmotic fragility (membrane defect) : hereditary spherocytosis
haemoglobin seperation A and F%: electropheresis, gas liquid chromotography
g6pd/pk deficiency
heinz body stains (crystal violet. methylviolet): denatured haemoglobin red cell injury
ham’s test: Paroxysmal nocturnal haemoglobinuria
management of haemolytic anaemia
folic acid supplementation
avoid precipitating factors
red cell transfusions
monitor for gallstones osteoporosis iron overload
splenectomy (extravascular for pk defiency and spherocytosis, sever elliptocytosis,thalaasaemia and autoimmune haemolytic anaemia
indications for splenectomy
transfusion dependence (regular and iron chelation)
growth delay( chronic anaemia)
physical limitation Hb < 8g/dl (F 12.5-15.5 , M13.5-17.5)
hypersplenism (pooling /exacerbation)
age not <3 due to role in early immunity
before age 10 to maximise pubertal growth
haemoglobin hammersmith
heinz body haemolytic anaemia, mutation disrupts haem contact reduced oxygen affinity
6months anaemia jaundice pigmenturia
