Abnormal Hemostasis

Question 1

Thrombocytopemia

Answer 1

decreased platelet count

Question 2

Thrombocytosis

Answer 2

benign increase

Question 3

thrombocythemia

Answer 3

neoplastic increase

Question 4

Heparin Induced Thrombocytopenia

Answer 4

thrombosis and thrombocytopenia

Heparin and PF4 complex and antibodies form against it

Question 5

ITP

Immune thrombocytopenia

Answer 5

Anti-2b3a antibodies-splenic macrophage consumption of platelet-antibody complex. Commonly due to viral illness

Lab

• increase in megakaryocytes on bone marrow biopsy
• Increased bleeding time, decreased platelets

Treatment steroids, IV immunoglobulin

Question 6

TTP

Thrombotic thrombocytopenic pupura

Answer 6

Inhibition or deficiency of ADAMTS 13 (vWF metalloprotease) –> degradation of vWF multimers

Pathogenesis: large vWF multimers–> increased platelet adhesion –> increased platelet aggregation and thrombosis

Labs: schistocytes, increased LDH

Symptoms: pentad of neurologic and renal symptoms, fever, thrombocytopenia, and microangiopathic hemolytic anemia

Treatment: plasmapheresis, steroids

Question 7

HUS

Answer 7

hemolytic uremic syndrome

Question 8

What are causes of decreased number of platelets?

Answer 8

1. alterations in bone marrow
2. hereditary thrombocytopenia
3. abnormal hematopoiesis
4. drug induced thrombocytopenia
5. dilutional

Question 9

What are causes of increased number of platelets?

Answer 9

1. splenectomy
2. reactive thrombocytosis
3. autonomous thrombocytosis-cluster of platelets-bleeding may occur

Question 10

What are causes of qualitative disorders of platelets?

Answer 10

1. disease induced platelet defects
2. drug induced platelet defects
3. diet induced platelet defects

Question 11

What are some congenital disorders that result in bleeding?

Answer 11

1. Glanzmann’s thrombasthenia
   - autosomal recessive
   - 2b3a defect
   - aggregation defect
   - bleeding time increased
2. Bernard-Soulier disease
   - autosomal recessive
   - 1b defect
   - adhesion defect
   - bleeding time increased
3. storage pool disease
   - decrease dense granule content, no aggregation
4. other disorders
   - purpura of unknown origin=gray platelet syndrome-lack of alpha granules

Question 12

What are some acquired disorders of platelets?

Answer 12

1. metabolic disorders-uremia

2. myeloproliferative disorders-polycythemia vera

Question 13

What are vascular disorders called?

Answer 13

nonthrombocytopenic purpuras

-easy bruising, bleeding from mucosa, purpura, vasculitis

Question 14

What is ehler danlos syndrome?

Answer 14

congenital subendothelial disorder of hypermobile joints

Question 15

Do hemophilias have an increased bleeding time? WHat about von willebrand’s disease?

Answer 15

hemophilias-no

von willebrand’s-yes

Question 16

What is digested by plasmin in secondary fibrinolysis?

Answer 16

fibrin and fibrinogen