Flashcards in Thrombocytopenia Deck (15)
less than 150k platelets
what is the regulator of platelet production?
what are the three general causes of thrombocytopenia?
3. sequestration (loss)
which medications / drugs can cause thrombocytopenia?
1. chemotherapy agents
what are the three subcategories of underproduction causing thrombocytopenia?
1. destruction of megakaryocytes
2. inadequate precursor elements
3. marrow replacement
what is the primary mechanism of pernicious anemia?
underproduction / ineffective production of precursors (B12)
what are the megakaryocyte levels in pernicious anemia?
normal or increased (trying to make more platelets)
what is a confirmatory test for pernicious anemia?
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
what is the first line of defense in ITP treatment?
IV steroids (splenectomy is curative)
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
pancytopenia is usually due to what cause?
what is the most common cause of thrombocytopenia due to underproduction?
for every unit of blood what is the increase in platelets?