Bleeding Disorders Flashcards
haemorrhagic diathesis is any quantitative or qualitative abnormality inhibition of”
Platelets
vWF
coagulation factors
when taking a bleeding history what must you think about?
has the patient actually got a bleeding disorder? how severe? pattern of bleeding congenital or acquired mode of inheritance
how may you determine if a patient actually has a bleeding disorder?
o Bruising
o Epistaxis
o Post-surgical bleeding – dental surgery, circumcision, tonsillectomy, appendicectomy
o Menorrhagia
o Post-partum haemorrhage – most not due to bleeding disorders
o Post-trauma
how may you decide how severe the bleeding disorder is?
o How appropriate is the bleeding?
o Some might bleed only after major things e.g. surgery, trauma. Some just after mild
injury
o Unprovoked bleeding is pathological
o Mild provoked bleeding required investigation
what is platelet type bleeding?
§ Low platelets and vWF § Mucosal § Epistaxis – recurrent and doesn’t stop § Purpura + petchiae § Menorrhagia § GI
what is coagulation factor type bleeding?
§ Articular – bleeds into joints – commonly knees, ankles, shoulders, elbows,
(hips)
• Weight bearing joints, typically hinge joints
• Results in muscle atrophy
§ Muscle haematoma
• Not provoked
§ CNS – intracranial haemorrhage
how would you determine if a bleeding disorder is congenital or acquired?
o Previous episodes
o Age at first event
o Previous surgical challenges
o Associated history
discuss haemophilia A and B
- X-linked
- Identical phenotypes – depends on residual FVIII/IX
- 1 in 10,000 and 1 in 60,000
- Severity of bleeding depends on the residual coagulation factor activity
- <1% severe – bleed without any trauma at all, bleeds every couple of weeks
- 1-5% moderation
- 5-30% mild – need to be detected but don’t commonly have any issues
- A = FVIII
- B = FIX
clinical features of haemophilia
- Haemarthrosis – classically hinge and weight bearing
- Muscle haematoma – calf, biceps
- CNS bleeding
- Retroperitoneal bleeding
- Post-surgical bleeding – preventable with appropriate clinical preparation
complications of haemophilia
• Synovitis
o Macrophages produce inflammatory cytokines which destroy intra acticualr cartilage
• Chronic haemophilic arthropathy
• Neurovascular compression (compartment syndromes)
• Other sequelae of bleeding e.g. stroke
diagnosis of haemophilia
- Clinical
- Prolonged APTT – 12, 11, 10, 8, 9 deficiencies
- Normal PT – 7, 10, 5, 2, 1 deficiencies
- Normal BT
- Reduced FVIII or FIX
- Genetic analysis
- Most boys present between 6 months and 2 years
treatment of haemophilia
• Coagulation factor replacement FVIII/IX
• Now almost entirely recombinant products
• DDAVP
• Tranexamic acid
• Emphasis on prophylaxis in severe haemophilia
o With aim of keeping trough level of 2% as moderate haemophilia do not have
spontaneous bleeds
• Gene therapy?
Haemophilia Treatment
• Splints
• Physiotherapy
• Analgesia
• Synovectomy
• Joint replacement
complications of treatment of haemophilia
• Viral infection o Coagulation factor pre 1989 o HIV o HBV, HCV o Others/vCJD? • Inhibitors o Severely infected o First 20-50 days of exposure o Anti FVIII Ab – no F8 so make Ab on exposure o Rare in FIX – fewer null mutations • DDAVP – desmopressin o Releases F8 and vWF from endothelial cells, goes up for a day to allow dental surgery etc o MI – cannot give to high risk of vascular disease o Hyponatraemia (babies)
discuss von Willebrand disease
• Common 1 in 200 • Variable severity • Autosomal dominant • Platelet type bleeding – mucosal • Quantitative and qualitative abnormalities of vWF • Type 1 – quantitative deficiency • Type 2 (A,B,M,N) qualitative deficiency determined by the site of mutation in relation to vWF function • Type 3 – severe (complete) deficiency • Treatment o vWF concentrate or DDAVP o Tranexamic acid o Topical applications o OCP etc
name some acquired bleeding disorders
• Thrombocytopenia • Liver failure • Renal failure • DIC • Drugs o Warfarin, heparin, aspirin, clopidogrel, rivaroxaban, apixaban, dabigatran, bivalirudin
