Heritable Bleeding Disorders Flashcards

1
Q

How does platelet adhesion and activation occur?

A

Platelets adhere to damaged endothelium and undergo activation. Platelets aggregate into a thrombus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What types of bleeding disorders are there?

A
  • Congenital (single defect)
  • Acquired (multiple defects)
  • Coagulation defects (deep muscular & joint bleeds)
  • Platelet/vessel wall (skin & mucosal)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the primary & secondary formations of a haemostatic plug?

A
Primary= aggregation (platelets)-> clotting
Secondary= coagulation-> thrombin->fibrin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the differences between vascular/platelet and coagulation defects?

A
  • V= Petechiae & superficial bleeding, skin & mucous membranes, Spontaneous, bleeding immediate, prolonged, non-recurrent
  • C= Deep spreading haematoma, haemarthrosis, retroperitoneal bleeding, prolonged often recurrent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe von Willebrand disease

A
  • Absent molecule=severe
  • Reduced molecule= less severe
  • RCoF value below 30
  • Stops production of fibrin
  • Autosomal dominant
  • Males and females
  • Variable penetrance
  • Blood group O decreased chance
  • Treatment: Vaccinate Hepatitis, antifibrinolytics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Name some heritable coagulation factor deficiencies

A
  • XII=Autosomal
  • XI=Autosomal, rare
  • IX=Haemophilia B,X-linked
  • VIII=Haemophilia A, X-linked
  • VII=Autosomal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe haemophilia

A
  • X-linked recessive
  • Haem A= 1/5000, factor VIII deficiency
  • Haem B= 1/30000, factor IX deficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the intrinsic and extrinsic components of blood

A
E= Ca2+, Factor VII, tissue factor thromboplastin
I= Ca3+, platelet, factor 8,9,11,12, phospholipid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What bleeding/coagulation disorders are screened for?

A
  • Thrombocytopenia
  • Disorders of platelet function
  • Von Willebrand disease
  • Factor VIII deficiency
  • Vascular disorder
  • Disorder of fibrinolysis
  • Mild coagulation factor deficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the test used in a coagulation screen and are there any limitations?

A
  • platelet count & bleeding time for platelet function
  • Tests prothrombin time, fibrinogen & Activated Partial Thromboplastin Time
  • Not specific for cause, some individuals have constituents out of range but are normal, contamination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Name some acquired bleeding disorders

A
  • Vit K deficiency
  • Disseminated intravascular coagulation
  • Immunoglobulin-mediated factor deficiency/factor VIII deficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What combination of finding will be seen in von Willebrands syndrome?

A

Prothrombin time unaffected. Bleeding time: prolonged . Platelet count: unaffected.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which diagnostic test is used to measure the intrinsic coagulation pathway?

A

APTT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly