haemophilia Flashcards
what are the two types of hemophilia ?
hemophilia type A and type B
what are the deficient factors in each type of hemophilia ?
A - factor 8
B - factor 9
what is the inheritance pattern of hemophilia ?
x-linked recessive
what are the features of hemophilia ?
1- hemarthrosis - bleeding of joints
2- soft tissue hematoma
3- prolonged bleeding after surgery or dental extractions
4- large deep ecchymotic patches
what gene mutation is hemophilia A associated with ?
defect in the F8 gene
what is the difference between congenital hemophilia and acquired hemophilia ?
congenital - deficiency in factor 8
acquired - autoimmune condition where there are antibodies against factor 8
what are the situations that may lead to a diagnosis of hemophilia ?
spontaneous joint bleeding
marked bruising after circumcision
excessive bleeding after surgery
what is seen on lab evaluation in cases of haemophilia ?
1- prolonged PTT due to affection of the intrinsic pathway
2- decreased factor 8 activity
3- mutations detected in F8 genee sequencing
what does the severity of hemophilia depend on ?
the clotting factor level
mild - 5-40
moderate - 1-5
severe - <1
what are the treatment options for hemophilia ?
replace the missing factors with concentrates - factor 8 replacement 2-3 times a week
increase endogenous factors
antifibrinolytics
platelets
what is considered curative therapy in hemophilia ?
liver transplant
gene therapy
what is the aim level of factor 8 ?
keep it above 1
what is the focus of both primary and secondary prophylaxis in hemophilia ?
1- primary prophylaxis - avoidance of any joint abnormality
2- secondary prophylaxis - avoidance of the progression of any arthropathy
what is the most serious bleeding symptom in hemophilia ?
intracranial haemorrhage
what is the most serious complication associated with hemophilia A ?
the development of anti factor 8 inhibitors
what is the cause of development off anti factor 8 inhibitors ?
caused by factor 88 replacement therapy
what are the two approaches associated with antibody formation against factor 8 ?
can either be high or low titre
low titre - below 5 , patient can continue using factor 8 products
high titre- above 5 patients won’t benefit from factor 8 products
how can high titre antibodies be resolved ?
immune tolerance induction
which monoclonal antibody has been used for the replacement of factor 88 ?
emicizumab
what is the epidemiology in hemophilia A ?
almost always in males with sporadic cases in females
how can you differentiate between inhibitors and deficiency ?
mixing study
