12 - Bleeding Disorders and Thrombocytopenia Flashcards
What hematologic condition is most associated with petechiae?
Thrombocytopenia! (Ecchymosis is more common with platelet dysfunction)
Your patient has the following lab results and peripheral blood smear. What is the primary defect in hemostasis in this patient?
Defect in platelet number.
What is immune thrombocytopenia (ITP)? How is it diagnosed?
Can be primary (no identified cause) or secondary (identified cause, such as underlying disease or drug exposure).
Disagnosed by measurement of platelet levels (<100 x 10^9/L) and exclusion fo non-autoimmune causes of thrombocytopenia.
- response to therapy is hte most compelling diagnostic evidence
- platelet-bound or circulating auto-Ab against platelet antigens found in ~60% of pts
How does immune thrombocytopenia usually present clinically?
- Petechiae and ecchymoses
- Spontaneous bleeding is uncommon when the platelet count is >20 x10^9 /L^2
- Bleeding episodes, most commonly mucocutaneous
- Intracranial hemorrhage and other major internal bleeding is rare
How does immune thrombocytopenia impact children? How does it compare to adult ITP?
Children may be affected at any age, but peak incidence is in early childhood (1-6 yo)
In contrast to adult ITP, pediatric ITP is more likely due to viral illness and usually resolved spontaneously without treatment.
- ~25% of childhood ITP becomes chronic
What are 4 immune modulation therapies that can be used to treat immune thrombocytopenia (ITP)?
- Corticosteroids including dexamethosone or prednisone.
- IVIg
- Splenectomy
- Rituximab
What are 2 platelet related therapies that can be used to treat immune thrombocytopenia (ITP)?
Increased platelet production via thrombopoietin agonists:
- Eltrombopag
- Romiplostim
What is DIC?
An acquired syndrome characterized by systemic intravascular coagulation.
Coagulation is always the initial event, typically followed by bleeding (consuptive coagulopathy)
What are the conditions associated with DIC?
There’s a LOT.
What does laboratory evaulation of DIC include (ie what tests are done and what are the results of those tests) - there are 4?
- Prolonged clotting times (PT, PTT, thrombin time)
- Decreased factor activities
- Elevated D-dimer
- Sometimes thrombocytopenia and hemolytic anemia.
DIC is associated with __________ __________ and __________. Bleeding complications are common.
Microvascular infarction and hemorrhage.
What organs, other than the vasculature, can be involved in DIC?
- Liver
- Kidneys
- CNS
What is the primary treatment of DIC?
It involves correction of the underlying cause of the disease.
Other supportive therapies include the replacement of clotting factors through the use of blood product transfusion (fresh frozen plasma, cryoprecipitate, and platelets).
What is hemophilia?
An inherited bleeding disorder in which there’s a deficiency or lack of:
Factor VIII (hemophilia A)
Factor IX (hemophilia B)
or
Factor XI (hemophilia C)
How would you treat hemophilia?
Treatment requires replacement of the deficient clotting factor, most commonly with recombinant or plasma-derived clotting factors.