Thrombocytopenia Flashcards Preview

Year 2 Hematology > Thrombocytopenia > Flashcards

Flashcards in Thrombocytopenia Deck (15)
1

definition: thrombocytopenia

less than 150k platelets

2

what is the regulator of platelet production?

thrombopoietin

3

what are the three general causes of thrombocytopenia?

1. underproduction
2. destruction
3. sequestration (loss)

4

which medications / drugs can cause thrombocytopenia?

1. chemotherapy agents
2. alcohol

5

what are the three subcategories of underproduction causing thrombocytopenia?

1. destruction of megakaryocytes
2. inadequate precursor elements
3. marrow replacement

6

what is the primary mechanism of pernicious anemia?

underproduction / ineffective production of precursors (B12)

7

what are the megakaryocyte levels in pernicious anemia?

normal or increased (trying to make more platelets)

8

what is a confirmatory test for pernicious anemia?

methylmalonic acid

9

what are the features of immune (idiopathic) thrombocytopenic purpura (ITP)?

1. accelerated destruction of platelets
2. normal or increased megakaryocytes
3. antiplatelet antibodies (IgG usually) - destroyed by spleen

10

what is the first line of defense in ITP treatment?

IV steroids (splenectomy is curative)

11

what are the features of heparin induced thrombocytopenia?

1. immune mediated destruction of platelets
2. antibodies form in response to heparin and platelet specific PF4 complex

12

pancytopenia is usually due to what cause?

underproduction

13

what is the most common cause of thrombocytopenia due to underproduction?

medications

14

for every unit of blood what is the increase in platelets?

5000

15

underproduction is usually associated with decrease in how many cell lines?

two or more