Coagulation Disorders

Question 1

How is the body’s clotting system balanced?

Answer 1

• Clotting factors (platelets, TF, etc)

- Anti-clotting factors (NO, protein C/S, etc)

Question 2

What are examples of vessel bound clot INHIBITORS?

Answer 2

• NO
• Prostacyclin
• Vascular endothelial ADPase

Question 3

What are examples of vessel bound clot initiators?

Answer 3

• TF
• vWF
• TXA2
• Collagen

Question 4

What does the cascade of soluble clotting factors consist of?

Answer 4

Intrinsic and extrinsic pathways leading to the common pathway

Question 5

Which blood test evaluates the extrinsic pathway of clotting?

Answer 5

PT

Question 6

Which blood test evaluates the intrinsic pathway of clotting?

Answer 6

aPTT

Question 7

What is the MC inherited bleeding disorder?

Answer 7

von Willebrand disease

Question 8

Describe vWF

Answer 8

• Promotes adhesion and aggregation of platelets

- Carrier of Factor VIII

Question 9

What breaks down ultra-large multimers of vWF?

Answer 9

ADAMTS13 enzyme

Question 10

MC type of vWF disease?

Answer 10

Type 1

Question 11

Describe Type 1 vWF disease

Answer 11

• Autosomal co-dominant
• MC type
• Decreased quantity of vWF and FVIII activity (results in increased bleeding)
• Tx: DDAVP (nasal spray or IV)

Question 12

What patients normally have low levels of vWF and F VIII?

Answer 12

Type O blood

Question 13

What type of vWF disease should NOT be treated with DDAVP?

Answer 13

Type 2b (excessively big multimers of vWF) - can worsen thrombocytopenia and precipitate abnormal clotting

Question 14

Describe hemophilia A

Answer 14

• Deficiency of F VIII

- X linked recessive (severe only in males)

Question 15

Clinical presentation of hemophilia A

Answer 15

Easy bruising or bleeding (especially in male toddlers)

Question 16

How to differentiate child abuse from hemophilia A?

Answer 16

Hemophilia A is NOT a/w fractures

Question 17

Treatment of hemophilia A

Answer 17

IV recombinant F VIII

prophylaxis also desirable

Question 18

Describe hemophilia B

Answer 18

• Deficiency of F IX
• X-linked recessive
• Clinically identical to hemophilia A

Question 19

Treatment of hemophilia B

Answer 19

Recombinant F IX concentrate

Question 20

Describe F XI deficiency

Answer 20

• Autosomal co-dominant

- MC in Jewish population

Question 21

Clinical presentation of F XI deficiency

Answer 21

• Few are symptomatic
• Most present in adulthood
• Similiar symptoms to hemophilia (easy bruising and bleeding)

Question 22

Treatment of F XI deficiency

Answer 22

FFP

Question 23

Describe Vitamin K including its role in clotting

Answer 23

• Fat soluble vitamin, absorbed through gut
• Activation of many proteins including clotting factors II, VII, IX, X
• Activation of anti-thrombotic proteins C and S

Question 24

Why can pathological bleeding/thrombosis occur in liver failure?

Answer 24

Liver is major homeostatic organ - dysfunction throws the hemostatic balance out of whack

Question 25

How to treat coagulopathy of liver disease?

Answer 25

FFP - then you can anticoagulate after if thrombosis is a significant problem

Question 26

Describe coagulopathy of kidney disease

Answer 26

Usually more mild than that of liver disease

Question 27

Treatment of coagulopathy of kidney disease

Answer 27

Restore renal function first! Then FFP/transfusion may help

Question 28

Clinical hallmark of DIC?

Answer 28

Diffuse bleeding frequently from mucosa/sites of previous surgery and organ failure d/t thromboses

Question 29

Lab findings characteristic of DIC

Answer 29

- Microangiopathic Hemolytic Anemia | - Thrombocytopenia

Question 30

How to differentiate DIC from TTP?

Answer 30

PT and aPTT should be NORMAL in TTP (also fibrin degradation products)

Question 31

How to treat DIC?

Answer 31

- First, address underlying cause - Next consider FFP - Use transfusions sparingly - Anticoag is risky

Question 32

What blood test monitors unfractionated heparin activity?

Answer 32

aPTT

Question 33

Describe hypercoaguable states in general

Answer 33

- Pathologic thrombosis (particularly in venous structures) | - Excessive activation of soluble clotting factors

Question 34

What are the inherited hypercoaguable states?

Answer 34

- Factor V Leiden | - Prothrombin gene mutation G20210A

Question 35

What is the MC inherited hypercoaguable state?

Answer 35

Factor V Leiden

Question 36

What does the Factor V Leiden mutation cause?

Answer 36

Resistance to the inhibitory effects of activated Protein C

Question 37

Situational risk factors for hypercoaguable states?

Answer 37

- Surgery - Immobilization - Pregnancy - HRT - HIT

Question 38

Acquired risk factors for hypercoaguable states?

Answer 38

- IBD - Portal HTN - Cancer and chemo - Nephrotic syndrome - Anti-phospholipid antibody syndrome (lupus anticoag)