haemolytic anaemia Flashcards
(21 cards)
haptoglobin levels in haemolysis
LOW !
- haptoglobin produced in liver
- binds to free haemoglobin
low ADAMTS13
confirm diagnosis of thrombotic thrombocytopenic purpura (TTP)
LDH in haemolysis
raised ! due to increased cell turnover
hereditary spherocytosis inheritance
autosomal dominant (nothern europe descent)
causes fragile, sphere shaped red bloood cells that easily break when passing through the spleen
key findings for spherocytosis
failure to thrive
jaundice, gall stones
- (may be neonatal jaundice)
splenomegaly
aplastic crisis precipitated by parovirus
MCHC elevated
management of spherocytosis
acute crisis
- supportive
- transfusion if necessary
long term
- folate replacement !
- splenectomy
diagnosis of spherocytosis
if obvious fam hx + sign on blood film - clinical
if not –> EMA binding test
inheritance / epidemiology of G6PD def
X-linked recessive (male)
more common in mediterranean + africa
what can precipitate a crisis in G6PD
drugs
- antimalarials - primaquine
- ciprofloxacin
- sulph - group - sulfasalazine, sulfonylureas (gliclazide)
broad (fava) beans
infection
features of G6PD def
neonatal jaundice
intravascular haemolysis
gallstones
splenomegaly
heinz bodies
- bite + blister cells
diagnosing G6PD
G6PD enzyme assay
- check levels 3 months after an acute episode of haemolysis
commonest type of autoimmune haemolytic anaemia (AIHA)
warm !
warm autoimmune haemolytic anaemia (AIHA) pathophys
antibody (usually IgG) causes haemolysis best at body temp + haemolysis tends to occur in EXTRAvascular sites
–> e.g. spleen
causes of warm AIHA
idiopathic
autoimmune disease - SLE
neoplasia - lymphoma, CLL
drugs - methyldopa
management of warm AIHA
mx of underlying
steroids (+/- rituximab)
cold AIHA pathophys
usually IgM + causes haemolysis best at 4 degrees
haemolysis is mediated by complement + in more commonly INTRAvascular
features of cold AIHA
raynauds + acrocynaosis (blue fingers)
patients respond less well to steroids :(
causes of cold AIHA
neoplasia - lymphoma
infections - mycoplasma, EBV
key differences between warm and cold AIHA
warm
- extravascular haem
- IgG
- mx = steroids +/- rituximab
cold
- intravascular haem
- IgM
causes of microangiopathic haemolytic anaemia
HUS
DIC
thrombotic thrombocytopenic purpura (TTP)
SLE
cancer
acquired immune causes of haemolytic anaemia (coombs positive)
autoimmune - warm/cold
alloimmune - transfusion reaction, haemolytic disease of newborn
drugs - methyldopa, penicillin
