Bleeding Disorders Flashcards
What is Haemophilia A?
Deficiency of factor 8
What is Haemophilia B?
Deficiency of factor 9
What is the most common inherited bleeding disorder?
Von Willebrand disease
Haemophilia A
What is the mode of inheritence of haemophilia A and B?
X linked recessive
How does heamophilia A and B present?
Haemarthrosis/bleeding into joint
- Tense swollen knee without injury
Haematuria
Muscle haematoma
CNS bleeding
Retroperitoneal bleeding
Post surgical bleeding
Secondary arthritis
What investigations are used in haemophilia A and B diagnosis?
Factor 8/9 Assay
Increased APTT
- As intrinsic pathway is affected
Normal PT, platelets and vWF
Genetic analysis
How is haemophilia A and B managed?
Haemophilia A
- Purified factor 8
- Desmopressin, which increases factor 8 levels
Haemophilia B
- Factor 9 injections
Tranexamic Acid
Gene therapy
What is the prophylactic management of haemophilia A and B?
Splints
Physiotherapy
Analgesia
Synovectomy
Joint replacement
Regular coagulation factor injections
What does Residual Coagulation Factor Activity assess?
Severity of bleeding
What is mild haemophilia?
5-30% residual coagulation factor activity
What is moderate haemophilia?
1-5% residual coagulation factor activity
What is severe haemophilia?
<1% residual coagulation factor activity
Give complications of haemophilia A and B
Synovitis
Chronic haemophilic arthropathy, arthritis caused by bleeding into joints
Compartment syndrome
Other sequelae of bleeding, such as stroke
What is type 1 Von Willebrand disease
Partial reduction in vWF
What is type 2 Von Willebrand disease?
Abnormal form of vWF
What is type 3 Von Willebrand disease?
Total lack of vWF, autosomal recessive
What mode of inheritence is von willebrand disease?
Various subtypes, however the most common is autosomal dominant
How does von willebrand disease present?
Mucosal/capillary bleeding
Easy bruising
What investigations are used in von willebrand disease?
Low or abnormal vWF
Slightly increased APTT
Normal PT
Normal platelets
Prolonged bleeding time
How is von willebrand disease managed?
vWF concentrate
Tranexamic acid for mild bleeding
DDVAP (Desmopressin) infusions
- Induces release of vwf
What is autoimmune thrombocytopenic purpura (ITP)?
Thrombocytopenia characterised by antibodies against the antigens on the platelet surface, resulting in removal via the reticuloendothelial system
What age group does ITP affect?
Middle aged women and children
How does ITP present?
Recurrent epistaxis
Ecchymosis/bruising
Gingival bleeding
Menorrhagia
Recent URTI
What investigations are used in ITP?
FBC
- Thrombocytonpenia
Blood film
Bone marrow biopsy
How is ITP managed?
Emergency
- Platelet transfusion
- IV methylprednisilone
- IV immunoglobulin
If platelet count is over 30
- Observation
If platelet count is less than 30
- Oral prednisilone, first line
- IV immunoglobulin
- If resistant, consider splenectomy
What is thrombotic thrombocytopenic purpura?
Deficiency of enzyme ADAMTS13 which breakdowns large multimers of von Willebrand’s factor
What causes thrombotic thrombocytopenic purpura?
Post-infection
Pregnancy
Drugs
- Ciclosporin
- Oral contraceptive pill
- Penicillin
- Clopidogrel
- Aciclovir
Tumours
SLE
HIV
What are features of thrombotic thrombocytopenic purpura?
Rare, typically adult females
Fever
Fluctuating neuro signs
Microangiopathic haemolytic anaemia
Thrombocytopenia
Renal failure
What is Wiskott-Aldrich syndrome?
Primary X linked recessive immunodeficiency due to a combined B and T cell dysfunction, caused by mutation in the WASP gene and characterised by recurrent bacterial infections, eczrma and thrombocytopaenia
At what platelet level is autoimmune thrombocytopenic purpura treated?
Only treat if platelets <30x10^9/l
What coagulation factors are affected with heparin?
Affects activation of 2 9 10 11
What factors are affected with warfarin?
Affects synthesis of 2 7 9 10
What coagulation factors are affected by DIC?
1 2 5 8 11
What coagulation factors are affected in liver disease?
1 2 5 7 9 10 11
What are the blood clotting results in haemophilia?
APTT inncreased
PT normal
Bleeding time normal
Describe the blood clotting results in vWd
APTT increased
PT normal
Bleeding time increased
Describe the blood clotting results in vitamin K deficiency
APTT increased
PT increased
Bleeding time normal
Give causes of thrombocytopenia
DIC
Haemotological malignancy
Aspirin
Diuretics
Alcohol
Liver disease
Hypersplenism
EBV, HIV, Hepatitis
Pregnancy
SLE, antiphospholipid syndrome
Vitamin B12 deficiency
What is the mode of action of LMWH?
Activates antithrombin III and forms a complex that inhibits factor Xa
What monitoring is used in LMWH?
Anti factor Xa, although routine monitoring is not necessary
What monitoring is used in standard heparin?
Increased APTT
What is the mode of action of standard heparin?
Activates antithrombin III and forms a complex that inhibits thrombin, factors Xa, IXa, Xia and XIIa
How is heparin induced thrombocytopenia managed?
Switch to a direct thrombin inhibitor, such as argatroban
