Pharmacotherapy is just like therapy, but one uses pharmaceutical drugs. Patients with HIT are at high risk for thrombotic events and are mostly prescribed to undergo pharmacotherapy. As a pharmacology student, what do you know about the process as a whole? Take up the quick quiz below on the pharmacotherapy of HIT topic and get to refresh your memory. All the best!
Onset is within 4 days
Onset is usually 5 to 10 days
Platelet count typically 100-150
Platelet count typically 20-150
Incidence is more common than HIT
Incidence is less common than HIT
Recovery is longer than with HIT
Recovery is shorter than with HIT
Caused by direct drug induced platelet aggregation
Cause is immune-mediated
Seroconversion
Isolated HIT
Heparin-induced thrombocytopenia thrombosis syndrome (HITTS)
Seroconversion
Isolated HIT
HITTS
Give the patient FULL therapeutic doses of an alternative anticoagulant such as a LMWH.
Give the patient FULL therapeutic doses of an alternative anticoagulant, such as lepirudin, argatroban, or fondaparinux.
If a thrombus is found, begin warfarin only after platelet count has substantially recovered (>150k).
Consider platelet transfusion.
Recent heparin (past 100 days).
Heparin duration > 2 days
UFH > LMWH
Female > male
Post surgery
Seroconversion
Isolated HIT
HITTS
Heparin: PF4 complex binds to the anchored IgG Ab and crosslinks with other IgG Abs on the platelet, producing additional PF4 which perpetuates further platelet activation.
B lymphocytes generate IgG antibodies to the complex, which then bind to the Fc receptors on platelet cell surfaces.
The platelets release PF4 and microparticles, which are thrombogenic and promote thrombin production.
Platelet counts fall below
Median platelet count is about 55x10^9/L
Most commonly thrombocytopenia occurs 5-10 days after heparin exposure.
IgG antibodies to heparin-PF4 complexes.
True
False
Lepirudin
Fondaparinux
Argatroban