Bleeding Disorders Flashcards
Define bleeding diathesis
Increased susceptibility to bleeding due to qualitative/quantitative defects of inhibition of the function of platelets, vWF or coagulation factors
What are the key questions in a bleeding history?
Has patient got a bleeding disorder?
How severe is it?
Pattern of bleeding - thrombocytopenic/vWF vs coagulation
Congenital vs acquired - prev. episode/age of onset
FH
Where do the bleeds occur in mucosal (thrombocytopenic/low vWF) bleeding?
Mucosal, GI, menorrhagia, petechiae/purpura, epistaxis
Where do bleeds occur in coagulation occur deficiencies?
Articular, muscle haematomas, CNS
What is a classical presentation for someone with haemophilia?
Young boy presenting with intra-articular bleeds (esp. knee, ankle, shoulder, elbow)
What is key about the petechiae in thrombocytopenic bleeding?
Non-blanching
Why do you get muscle wasting in haemophilia?
Disuse
Muscle haematomas
How would a boy with haemophilia present with an intracranial bleed?
Focal signs, headache, loss of consciousness
What should you ask in history of bleeding about previous bleeds?
Bruising Epistaxis Post-surgical/trauma - tonsillectomy, dental surgery, circumcision, appendectomy Menorrhagia PPH Post-trauma
HOW appropriate was the bleeding?
How is haemophilia inherited?
X-linked
How do the presentations of haemophilia A and B differ?
They don’t
What changes the severity of bleeding in haemophilia A and B?
The residual factor 8/9 in their circulation
<1% severe - unprovoked bleeding
1-5% moderate
5-30% - tend to be okay apart from maybe needing pre-surgical preventative measures
What is haemophilia A a deficiency of?
Factor 8
What is haemophilia B a deficiency of?
Factor 9
What are the clinical features of haemophilia?
Intra-articular bleeds (esp. into weight bearing, hinge joints)
Muscle haematomas (esp. calves and biceps)
CNS bleeding
Retroperitoneal bleeding
Post-surgical bleeding
What are the clinical complications of haemophilia?
Synovitis
Chronic haemophilic arthropathy
Neurovascular compression
Other sequlae of bleeding (stroke)
Why does chronic haemophilic arthropathy occur?
Macrophages eat blood in IA bleeds –> inflammatory cytokines released which drives degeneration of articular cartilage and joint –> end stage joint dx in young adulthood
What X-Ray findings will you get with end stage chronic haemophilic arthropathy?
Joint space narrowing
Development of osteophytes
How do you manage chronic haemophilic arthropathy?
Joint replacement
How do you diagnose haemophilia?
Typical history
Screening - APTT normal, AP normal (only screens for factors, 1, 2, 5, 7, 10)
Reduced factor 8/9 - check via assay
Genetic analysis to identify mutation
How do you treat haemophilia?
Recombinant factor 8/9 (3x week for 8, 2wkly for 9)
DDVAP if mild
Tranexamic acid
Also may require splints, physio, analgesia, synovectomy, joint replacement
How does DDVAP work?
Releases stored factor 8 and vWF from endothelium
In which groups of people can you not use DDVAP for treatment of haemophilia?
Elderly and young kids as if may put them at risk of hyponatraemia
What are the treatment complications of haemophilia?
HIV/HBV, HCV/vCJD transmission is kind of a thing of the past
Inhibitors - antibodies against factor 8 in nulmutations (as body not seen factor 8 before, don’t tend to get nulmutations in factor 9)
How common is vWF disease?
1 in 200
How many types are there?
3
First 2 AD
Type 3 is AR
What are the clinical features of vWF disease?
Mucosal bleeding - post-surgical, GI, menorrhagia, petechiae/skin, epistaxis
What is the deficit in type 1 vWF disease?
Quantitative deficiency
What is the deficit in type 2 vWF disease?
Qualitative defect
What is the deficit in type 3 vWF disease?
Complete, severe deficiency
How do you treat vWF disease?
vEF concentrate DDAVP Tranexamic acid Topical applications OCP
What are the acquired bleeding disorders?
Thrombocytopenia Liver failure Renal failure DIC Drugs (e.g. warfarin, clopidogrel, rivaroxaban, heparin, aspirin etc.)
What are the reasons for thrombocytopenia?
Decreased production - marrow failure, asplasia, infiltration (e.g. ALL)
Increased consumption - immune ITP, DIC, hypersplenism (platelets caught in spleen)
What is DIC?
Abnormal coagulation disorder that occurs in the context of burns, sepsis, eclampsia, malignancy etc.
Leads to widespread activation of coagulation –> microvascular thrombi –> organ ischaemia and failure & consumption of platelets –> bleeding elsewhere
What is the lifespan of platelets?
10 days
What are the clinical features of thrombocytopenia?
Petechiae (esp in legs)
Ecchymosis
Mucosal bleeding
Rarely CNS bleeding
What is ITP?
Idiopathic thrombocytopenic purpura
Low platelets in absence of bone marrow failure and no other known cause
Tends to be autoimmune
What are the two different presentations of ITP?
Acute in children
Chronic in adults
What things are associated with ITP?
Infections (EBV, HIV)
Collagenosis
Lymphoma
Drug induced (quinine)
How do you diagnose ITP?
Isolated thrombocytopenia
Blood film is fine
Tend not to need to check bone marrow
How do you manage ITP?
Acute - rescue therapy with steroids and IV Ig
Chronic - splenectomy, thrombopoetin analogues (eltrombopag)
How does liver failure affect clotting?
Rebalanced haemostasis –> less stable balance between coagulation and anti-coagulation as liver responsible for making factors contributing to both
What factors are produced by the liver?
1, 2, 5, 7, 8, 9, 10, 11
What APTT, PT and fibrinogen test results would you expect to see in liver failure?
Prolonged APTT, PT and reduced fibrinogen
When do patients with liver failure tend to be at the biggest risk of bleeding?
From structural abnormalities, e.g. varices after trigger (e.g. infection)
What are the vitamin K dependent factors?
2, 7, 9, 10
How can you help prevent bleeds in patients with liver failure?
Vit K
FFP
What is haemorrhagic disease of the newborn?
Newborn’s have an immature coagulation system and are deficient in vitamin K therefore are prone to fatal haemorrhage
How is haemorrhagic disease of the newborn completely prevented?
Vit K injection at time of birth
