Hemostasis And Related Disorders

Question 1

Explain the steps and players of primary hemostasis and the two main receptors involved and their role?

Answer 1

Injured vessel exposes collagen. Von willebrand factor binds collagen. Palettes bind VWF via gp1b. Platelets release ADP and thromboxane a2 to stimulate platelet aggregation. Platelets bind fibrinogen via gp2b/3a.

Question 2

Primary hemostasis disorders are caused by what two principles?
What are the clinical symptoms of primary hemostasis disorders?

Answer 2

Not enough platelets or platelets not working
Skin and mucosal bleeding, so epitaxis, hemoptysis, gi bleeding, hematuria, menorrhagia.
Petechia 1-2mm
Purpura greater than 3 mm
Ecchymoses greater 1cm

Question 3

What is a normal platelet count?

Answer 3

150-400k

Question 4

What is the most common cause of thrombocytopenia in kids and adults?
What are the two forms?
How to treat?

Answer 4

Immune thrombocytopenia purpura
Acute in kids, usually following a viral infection
Chronic, in adults, usually associated with a chronic or autoimmune disease like lupus
Steroids and if refractory, take the spleen out

Question 5

Two forms of microangiopathic hemolytic anemia and their causes?
Treatment of TTP?
Treatment of HUS?
Symptoms?

Answer 5

TTP, can’t break down VWF so continue to use platelets to create small clots
HUS, damage to endothelial cells because of infection or drugs, commonly ecoli
HUS, fluids, transfusion, dialysis, Plasmaphereis and steroids.
TTP, steroids
Purpura, anemia, diarrhea, fever, kidney problems in hus, CNS in TTP

Question 6

What is the intrinsic pathway of clotting?
Extrinsic?
What does pt and ptt measure?

Answer 6

12,11,9 and 8 activate 10, 10 and 5 activate 2, 2 activates 1 or fibrinogen and 13 cross links
7 to 10 and so on.
Ptt intrinsic and pt extrinsic

Question 7

What is the inheritance of hemophilia 8?
Clinical symptoms?
Treatment?

Answer 7

X linked recessive
Bleeding
Give 8

Question 8

What is the most common inheritance of VWF deficiency?
Test for it?
Treatment?

Answer 8

Autosomal dominant
Abnormal ristocetin, platelets don’t clump because no VWF
Desmopressin

Question 9

What clotting factors are activated by vitamin K?

How is vitamin k activated?

Answer 9

2,7,9,10. And protein c and s

Epoxide reductase in the liver

Question 10

What is the problem with DIC?
1 lab value and 1 symptom and 1 scenario of DIC?
Test?
Treatment?

Answer 10

Widespread activation of coagulation and then bleeding because everything is consumed
Low fibrinogen, anemia, sepsis
D dimer
Treat underlying problem and transfuse blood and coag products

Question 11

What is the most common inherited hypercoagulable disorder?

Answer 11

Factor 5 leiden

Factor 5 can’t be broken down by c and s