haemophilia + thalassaemia Flashcards
(18 cards)
inheritaance of haemophillia
x-llinked recesssive
haemophilia A
deficiency of factor VIII (8)
haemophilia B
lack of factor IX (9)
features of haemophilia
haemoarthroses
haematomas
prolonged bleeding after surgery or trauma
blood test findings in haemophilia
- prolonged aPTT
bleeding time, thrombin time, prothrombin time all normal
what is deficient in alpha-thalassaemia
deficiency of alpha chains in haemoglobin
- 2 separate alpha-globulin genes are located on each chromosome 16
different severities of alpha thalassaemia based on no. of chains affected
1 or 2 = normal Hb, blood hypchromic + normocytic
3 = hypochromic microcytic anaemia with splenomegaly = HbH disease
4 (all alleles affected) = death in utero (hydrops fetalis)
Beta-thalassaemia major
absence of beta globulin chains
chromosome 11
Beta-thalassaemia major presentation
failure to thrive in 1st year of life + hepatosplenomegaly
- microcytic anaemia
HbA2 & HbF raised
HbA absent
Beta-thalassaemia major management
repeated transfusion
however, this can lead to iron overload -> iron chelation therapy (desferrioxamine) also required
inheritance of Beta-thalassaemia trait
autosomal recessive
Beta-thalassaemia trait presentation
mild hypochromic, microcytic anaemia
-> microcytosis is disproportionate to the anaemia
HbA2 raised !
commonest inherited bleeding disorder
vin Willebrand disease
vin Willebrand disease mode of inheritance
autosomal dominant
vin Willebrand disease presentation
epistaxis
mehorrhagia
(NOT hamoarthroses/haematomas)
vin Willebrand disease investigation findings
prolonged bleeding time
APTT prolonged
factor VIII levels REDUCED
vin Willebrand disease management
mild bleeding = tranexamic acid
desmopression - raises levels of vWF
factor VIII concentrate
bleeding gums, joint pains
vit C deficiency (scurvy)
