Hematology

Question 1

thrombotic thrombocytopenic purpura pentad.

Answer 1

fever, microangiopathic hemolytic anemia, thrombocytopenia (with associated petechiae), renal dysfunction, and neurological or mental status changes

Question 2

Heparin induced thrombocytopenia

Answer 2

Is a type II hypersensitivity reaction, where antibodies form against and bind to heparin-platelet factor 4 complexes on the surface of platelets.

Question 3

Febrile nonhemolytic transfusion reaction

Answer 3

1-6 hours after a blood transfusion with fever (usually T 38-39 C) and chills.
Is due to the leaking of cyotkines from donor red blood cells due to long periods of storage or by host preformed antibodies to donor white blood cells in the transfusion resulting in a reaction.
The fever often resolves spontaneously within 30 minutes even without treatment

Question 4

Heparin induced thrombocytopenia

Answer 4

There are two forms
Type I is non-immune and occurs in the first 2 days of therapy.
Type II normally occurs 5-10 days after administration and is due to the autoimmune destruction of platelets.
More commonly occurs with unfractionated heparin, but can also occur with low-molecular-weight-heparin (LMWH).
Those receiving an IV infusion may also have a systemic/anaphylactic reaction including fever, chills, tachycardia and shortness of breath.
Initial management: discontinuing heparin and to prevent further clotting, direct thrombin inhibitors (i.e. argatroban) or factor Xa inhibitors (i.e. fondaparinux) can be used.

Question 5

What is the recommended timeline for vaccination against encapsulated organisms and the initiation of penicillin prophylaxis for a patient scheduled to undergo a splenectomy?

Answer 5

Vaccination at least 2 weeks prior to surgery, and 3-5 years of penicillin prophylaxis beginning at the time of surgery.