Qualitative Platelet Defects Flashcards
What is the pathological defect in Bernard Soulier Disease and what laboratory wise do you see?
The GP 1b/V/IX receptor is missing and you will see thrombocytopenia with large platelets on peripheral smear.
What is the inheritance pattern of Bernard Soulier Disease?
Autosomal recessive
What do platelet aggregation studies show for Bernard Soulier Disease?
You will see absent or markedly reduced aggregation in response to Ristocetin and normal response to ADP, epinephrine, and Collagen.
What gene is affected in Gray Platelet Syndrome? What granule is missing?
NBEAL-2 (for the autosomal recessive form). Alpha granules are missing.
What are some clinical features of gray platelet syndrome? What are they predisposed to developing?
These patients will have thrombocytopenia (not all patients develop this) and gray platelets on peripheral smear. They are predisposed to developing Myelofibrosis
What are the aggregation study results you see in Grey Platelet Syndrome?
You will decreased aggregation to ADP and epinephrine. Ristocetin will be normal. Remember the granules are missing ADP and epinephrine. This affects the alpha granules.
What is an important medication to consider using for bleeding in chronic renal disease?
Desmopressin
What important medications used in CAD/MI are associated with drug induced thrombocytopenia?
IIb/IIIa inhibitors such as tirofiban, eptifibatide, abciximab
Plavix can cause what TMA disease?
TTP
What are the clinical features of Hermansky Pudlak Syndrome and what granules are affected? Mode of inheritance?
The clinical features include oculocutaneous albinism, pulmonary fibrosis, colitis, and neurological symptoms (nystagmus, seizures). The dense granules are affected. Autosomal recessive
In Chediak Higashi Syndrome what are the clinical features and what granules are affected?
Oculocutaneous albinism, immune deficiency, neurologic symptoms, cytoplasmic inclusions in diff cells. Dense granules are affected. Also autosomal recessive.
In Chediak Higashi syndrome, what gene is mutated on what chromosome?
Its the LYST gene (lysomsomal trafficking regulator) on chromosome 1.
With Quebec Platelet Disorder what granules are affected and what are the clinical features? What is deficient in aggregation studies?
The alpha granules are affected. They present with delayed bleeding. They have normal to reduced platelets. There is no aggregation to epinephrine.
What is the mode of inheritance with Quebec Platelet Disorder and what gene is affected?
It is autosomal dominant and PLAU (the uPA gene) on chromosome 10 is affected.
What clinical abnormalities are noted with RUNX1 mutations? What is the mode of inheritance?
It is autosomal dominant condition. Associated with variable thrombocytopenia, and variable platelet function defects, impaired megakarypoiesis, and predisposition to AML.
