hematology Flashcards
(98 cards)
pathophys of immune thrombocytponeic purpura?
autoimmune production of IgG against platelet antigens, ->consumed by splenic macrophages -> thrombocytopenia
which cells produce the antibodies in ITP?
splenic plasma cells
Lab findings in ITP
Decreased platelet count
Normal PT/PTT
Increased megakaryocytes on bone marrow biopsy
Treatment for ITP?
Corticosteroids, IVIG
-splenectomy for refractory cases - eliminates the site of the antibody production
Name two types of microangiopathic hemolytic anemia
- HUS
- TTP
thrombotic thrombocytopenic purpura pathophs (TTP)?
Decreased ADAMTS13 - ADAMST13 normally cleaves vWF multimers into smaller monomers for degradation. With decreased ADAMTS13, uncleaved monomers lead ot abnormal platelet adhesion - > microthrombi -> sheering of rbcs
Decreased ADAMTS13 is usually due to…
an acquired autoantibody
who usually gets HUS?
children with e coli O157:H7 infection
Clinical findings of microangiopathic hemolytic anemia (HUS and TTP)?
- skin and mucosal bleeding
- hemolytic anemia
- fever
- renal insufficiency (HUS)
- CNS abnormalities (TTP)
lab findings of microangiopathic hemolytic anemia (HUS and TTP)?
- thrombocytopenia with increased bleeding time
- normal PT/PTT
- anemia with schitocytes
- increased megakaryocytes on biopsy
uremia disrupts which parts of platelet function?
both adhesion and aggregation
bernard-soulier syndrome is due to a genetic deficiency of…
GPIb
what is the cause of glanzmann thrombasthenia?
genetic GPIIb/IIIa deficiency
Hemophilia A is a X linked deficiency of…
factor VIII
Hemophilia B =
Christmas Disease
Hemophilia B is a deficiency of…
factor IX
What is the most common coagulation factor inhibitor?
anti-FVIII
How can you differentiate hemophilia A from a coagulation factor inhibitor (autoantibody against factor VIII)
Upon mixing the patients plasma with normal plasma, the PTT will not correct due to the presence of the antibody (whereas it would correct with hemophilia A)
Most commonly inherited coag disorder?
Von Willebrand disease- genetic vWF deficiency
inheritance of most common type of vWF defieincy?
AD
lab findings of vWF disease?
- increased bleeding time
- increased PTT, normal PT
- abnormal ristocetin test
why is PTT increased in vWF disease?
VWF normally stabilizes factor VIII
treatment of vWF disease?
desmopressin
function of alpha 2 antiplasmin?
inactivates plasmin