Haemophilia A/B Flashcards
What causes haemophilia A
Clotting factor 8 deficiency - function or quatntiity
INheritance of haemophilia A
X linked recessive - rarely AI or cancer induced - autoantibodies
What clotting screen is affected in haemopilia A
Prolonged APTT
What causes haemophilia B
Factor IX deficiency
What is classed as severe haemophilia
<1% of factor available
What is mild v mod haemophilia
1-5% = mod
5-50% = mild
Symptoms of haemophilia
Severe epistaxis
Bleeding gums
Haematuria - gross or microscopic
Intra-articular or IM bleeds - haemarthrosis
Excessive bruising/ecchymoses, confusions or spontaneous haemorrhage
Prolonged bleeding after surgical or dental procedure or post venepuncture
Less common bleeding presentations in haemophilia
ICH - neurological symptoms
Haematemesis, melaena and frank rectal bleeding
Haemoptysis
Compartment syndrome
Important qs w haemophilia
Secondary symptoms such as fatigue or frequent infections, as they may indicate alternative diagnoses (e.g. haematological malignancy).
Drug history: several different medications can alter the ability of the clotting cascade to function effectively (e.g. warfarin, aspirin, NOACs).
Social history: consider the possibility of violence as the cause of excessive bruising or bleeding (e.g. domestic violence).
Family history: given that most haemophilia is inherited, it’s essential that you take a comprehensive family history.
Platelet disorders vs haemophilia
Platelet - petechial haemorrhages and ecchymoses - bruising
Haemophilia - Haematomas and haemoarthroses
Investgiations
FBC + extended clotting screen
Biochemical findings with haemophilia
Prolonged APTT
Reduced factor VIII, IX activity
If recent bleed - low Hb and haematocrit
Normal platelets, PT, fibrinogen and vWF
Prophylaxis in haemophilia
Prophylactic factor infusions - until child reaches maturity, cont long term
slow IV bolus up to 3 x a week
Severe factor deficiency before surgery prophylactic plan
Factor activity increased to 50-100% for 2-7 days esp brain or prostate
What med inhibits fibrinolysis without increasing VTE risk
Tranexamic acid
