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
What should be monitored in haemophilia
Factor and factor inhbiotr levels
Haemophilia joint health score calculated frequently
Medical identifiction bracelet for emergencie
Lifestyle with haemophilia
Avoid competitive contact sports unneccessary manual labour
Encorugar swimming, racket sports etc
Vaccines against hep A and B subcutaneously
What give in acute bleeds in haemophilia
Facot infusions, FFP or cryoprecipitate
Goals for % factor major haemorrhage
100%
Coagulation tests and group and sace
Minor haemorrhage factor level goals
30-50%, maintatin for several days
What can acute bleeds in mild haemophilia be treated with
Desmopressin - DDAVP
Genetic testing in pregnancy
Chorionic villus sampling- 11-14 weeks
Amniocentesis - 15-20 weeks
What should be administered as soon as positive haemophilia diagnosis in neonates
Recombinant factor
Complications of haemophilia
Repeated haemoarthroses -> arthropathy - painful and reduced ROM
Joint deformity
Soft tissue haemorrhages
Retroperitoneal bleeds
Haemotoma formation
What concerns are there with old haemophila patients
Blood transfusions in the 80s -> blood borne viruses eg HIV, hepatitis
What can reduce efficacy of factor theray esp in haemophilia A patients
Antibody inhibitor formation
Recognise plasma factors as forieng
Results in anaphylaxis when exposed to any factor product
Treatment for inhibitor antibody formation
Immune toleration induction - small quantities over period of time until inhibitor antibodies decerase
Avoid in haemophilia B patients - less effective, risk of anaphylaxis
What can reduce the risk of antibody inhibitor formation
Immunosupressnats w mild disease
