Defects in Coagulation factors Flashcards Preview

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Flashcards in Defects in Coagulation factors Deck (8)
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1

What are the general clinical features of secondary hemostasis ( coagulation cascade)?

Deep tissue bleeding into muscles and joints (hemarthrosis) and rebleeding after surgical procedures (eg circumcision and wisdom tooth extraction)

2

PT

Prothrombin Time
- Factor 7
- Factor 2, 5,10 and fibrinogen

Extrinsic pathway

3

PTT

Partial Thromboplastin Time
Intrinsic factors: 12, 11, 9, 8
Common: 2, 6, 10 and fibrinogen

4

Hemophilia A

Defect:

Labs:

Tx:

X-linked disorder
Factor 8 deficiency

Labs:
increase PTT, normal PT
Decrease factor 8
Normal platelet count and bleeding

Tx: recombinant factor 8

5

Hemophilia B

Defect

labs:

X linked disorder
Factor 9 deficiency

Labs:
increase PTT, normal PT
Decrease factor 9
Normal platelet count and bleeding

6

Von Willebrand disease

Defect

Presentation:

Labs:

Tx:

most common inherited coagulation disorder

vWF deficiency
Autosomal dominant

Presents: mucosal and skin bleeding
Low vWF impairs platelet adhesion

Labs:
Increase bleeding time
Increase PTT (factor 8 is stabilized by vWF)
Normal PT
Abnormal ristocetin test (induces platelt agglutination by causing vWF to bind to platelet GPIb)

Tx: Desmopressin

7

Coagulation factor inhibitor

Acquired antibody against factor 8 (most common) -- can be against any factor though,

Clinically similar to hemophilia A (if factor 8 is target)

PTT does not correct upon mixing with normal plasma
- Hemophilia A will correct

8

DIC

Wide spread activation of clotting due to pathological activation of coagulation cascade.

Causes: "STOP Making New Thrombi"

Sepsis
Trauma
Obstetric complication
acute Pancreatitis
Nephrotic syndrome
Transfusion

Lab: schiztocytes, increase fibrin split products (D-dimers), decrease fibrinogen, decrease V and 8