Bleeding Disorders Flashcards
(21 cards)
what is haemorrhagic diathesis?
Hemorrhagic diathesis, also known as bleeding diathesis, is a condition that makes a person more likely to bleed or bruise easily. It can cause internal or external bleeding.
- can be caused by inhibition of function of platelets, von Willebrand (vWF) and coagulation factors.
The severity of bleeding in haemophilia depends on?
The residual coagulation factor activity:
- < 1% severe
- 1-5% moderate
- 5-30% mild
Haemophilia clinical features
- x-linked so usually male
- haemarthrosis
- muscle haematoma
- CNS bleeding
- retroperitoneal bleeding
- post surgical bleeding
What are the clinical complications of haemophilia?
- synovitis
- chronic haemophilic arthropathy
- neurovascular compression (compartment syndromes)
- other sequelae of bleeding (stroke)
what causes haemophilia A?
deficiency of factor VIII
what causes haemophilia B?
deficiency in factor IX
how is haemophilia diagnosed?
- clinical: family history and pattern of bleeding
- isolated prolonged APTT: normal PT, reduced FVIII or FIX
- genetic testing
what is the treatment for mild haemophilia?
On demand > if there is a bleeding episode and peri-operatively:
- recombinant factor concentrate
- desmopressin DDAVP (haemophilia A)
- tranexamic acid
what is the treatment for severe haemophilia?
Prophylaxis:
- recombinant factor concentrates: extended or short half life
- Emicizumab (antibody) for haemophilia A
On demand IV clotting factors
how are the symptoms of haemophilia treated?
- physio and analgesia
- synovectomy
- joint replacement
What are the complications of haemophilia treatment?
Inhibitors:
The body’s immune system can produce antibodies that attack clotting factors, making it harder to treat bleeding. This is called developing inhibitors. Usually anti FVIII antibodies.
Infections:
Transfusions can cause infections, but the risk is low due to strict blood testing. Clotting factors made from human blood can also carry viruses like HIV and hepatitis, but the risk is very small.
DDAVP (desmopressin) can cause MI in rare cases. Also can cause hyponatraemia in babies.
What is the most common inherited cause of abnormal and prolonged bleeding?
Von Willebrand disease (VWD)
- mostly autosomal dominant
What causes Von Willebrand Disease (VWD)?
A deficiency, absence or malfunctioning of a glycoprotein called von Willebrand factor (VWF).
VWF is important in platelet adhesion and aggregation in damaged vessels.
Describe the 3 types of VWD.
- type 1 involves a partial deficiency of VWF and is the most common and mildest type.
- type 2 involves reduced function of VWF.
- type 3 involves a complete deficiency of VWF and is the most rare and severe type.
Von Willebran Disease clinical presentation
Platelet type bleeding (muscosal):
- bleeding gums with brushing
- nosebleeds (epistaxis)
- easy bruising
- heavy menstrual bleeding (menorrhagia)
- heavy bleeding during and after surgical operations
- family history of heavy bleeding (e.g. menorrhagia) or VWD is relevant.
VWD management
Von Willebrand disease does not generally require daily treatment. Management is needed in response to significant bleeding or trauma (to stop bleeding) or in preparation for operations (to prevent bleeding). Options include:
- desmopressin (stimulates release of vWF)
- tranexamic acid
- VWF infusion
- factor VII + VWF infusion
options for heavy menstrual periods:
- tranexamic acid
- mefenamic acid
- Mirena coil
- COCP
- hysterectomy (severe cases)
what causes Thrombocytopenia?
- acquired bleeding disorder > low platelet count
- decreased platelet production e.g. marrow failure, aplasia, infiltration
- increased platelet consumption: immune ITP, DIC, hypersplenism
Thrombocytopenia clinical presentation
- mild may be asymptomatic and found incidentally
Platelet counts below 50 x 10^9/L will result in easy bruising and prolonged bleeding times. May present with:
- nosebleeds
- bleeding gums
- heavy periods
- easy bruising
- haematuria
- rectal bleeding
Platelet counts below 10 x 10^9/L are at high risk of spontaneous bleeding. Particularly concerning:
- intracranial haemorrhage
- gastrointestinal bleeding
What is Immune Thrombocytopenic Purpura (ITP)?
What is ITP associated with?
ITP is a condition where antibodies are created against platelets. An immune response against platelets leads to their destruction and a low platelet count (thrombocytopenia).
- associated with infections (esp EBV, HIV), lymphoma and drug-induced.
- characterised by purpura
Immune Thrombocytopenic Purpura (ITP) Management
acute vs chronic
Acute:
- Prednisolone (steroids)
- IV immunoglobulins
Longer-term:
- thrombopoietin analogues (Eltrombopag, Romiplostim, Avatrombopag)
- immunosuppression
- splenectomy (rare)
how is haemorrhagic disease of the newborn prevented?
Completely preventable by administration of vitamin K at birth (I.M vs P.O).
