Hemostasis Trivial Pursuit PLT/Vasculature

Question 1

What does the PFA-100 test measure

Answer 1

Closure time for platelet plug

Question 2

A patient has a normal PT, APTT and platelet count but an increased bleeding time.
Platelet aggregation studies showed abnormal curves for all aggregating agents – except
the ristocetin curve was normal. What is the patient lacking and what is the name of
this disorder?

Answer 2

GP-IIb/IIIa – Glanzmanns Thrombathenia

Question 3

Why is megakaryocyte hyperplasia of the bone marrow seen in ITP?

Answer 3

The immune
system is attacking the platelets and this is a healthy bone marrow response

Question 4

How does thrombopoietin (TPO) work?

Answer 4

TPO binds to receptors on platelets and is
degraded. Decreased platelets in the blood lead to increased TPO in circulation which
stimulates megakaryocyte production

Question 5

Which disorder is characterized by prolonged bleeding time, giant platelets, and platelet
aggregation studies normal with all agents except ristocetin (ristocetin curve is
abnormal)?

Answer 5

Bernard Soulier

Question 6

In HIT, the antibody is only active in the presence of what substance?

Answer 6

Heparin (Heparin-
induced thrombocytopenia

Question 7

What is the antibody associated with HIT/HITTS

Answer 7

It is an Anti-PF4/Heparin complex
(IgG)

Question 8

Patient results: bleeding time- increased, APTT- increased, PT- normal, platelet count-
normal. Platelet aggregation is normal with all aggregating agents except ristocetin
(ristocetin curve is abnormal). To further narrow it down, you’ve added normal donor
plasma to the patient PRP. The ristocetin aggregation curve is now normal. What is the
most likely diagnosis of this patient?

Answer 8

von Willebrands Disease (type 1)

Question 9

A patient has the following laboratory findings: thrombocytopenia, MAHA with
schistocytes, and fluctuating neurological dysfunction. What other symptom would you
expect from this patient?

Answer 9

Progressive renal failure (TTP)

Question 10

Name me. Auto-antibodies can be made against me, leading to TTP. I cleave multimers
for a living. My mother’s name is Weibel Palade

Answer 10

ADAMTS13

Question 11

Name me. My platelets could go well on a sandwich because they resemble this.
Dilation of my platelets’ canicular system leads to a deficient release reaction?

Answer 11

Hemansky- Pudlak syndrome – Swiss cheese platelet

Question 12

How do you differentiate between TTP and HUS?

Answer 12

TTP- progressive renal failure and
neurological symptoms; HUS- acute renal failure and absence of neurological symptoms
(possible recent enteric infection)

Question 13

What is the name of the vascular layer made of broad flat endothelial cells?

Answer 13

Tunica
intima

Question 14

What receptor does vWF adhere to on the platelet and name the disorder in which this
receptor is deficient?

Answer 14

GP-Ib – Bernard Soulier

Question 15

What is the mechanism by which aspirin will affect platelet function?

Answer 15

Aspirin will inhibit
the enzyme Cyclooxygenase, which renders it unable to produce Thromboxane A2
(TXA2). Reduced levels of TXA2 will reduce platelet aggregation

Question 16

A pregnant woman comes into the ER with a history of preeclampsia, and is
experiencing nausea, malaise, and a low platelet count. What might you expect to see
on the patient’s peripheral blood smear and why is this significant?

Answer 16

Schistocytes (rbc
fragments) – suspect HELLP syndrome

Question 17

What stimulates shape change in platelets?

Answer 17

Platelet activation induced by PLT adhesion

Question 18

How does prostacyclin contribute to vascular function in hemostasis

Answer 18

It normally inhibits
platelet adhesion (and is a vasodilator)

Question 19

At what point can platelet activation no longer be reversed?

Answer 19

after release rxn and dump of granules

Question 20

What substance is present in the underlying basement membrane of the tunica intima
that is important in binding Von Willebrand’s factor?

Answer 20

collagen

Question 21

Describe the phenomena of EDTA clumpers and their possible effect on the patient’s
platelet count and white blood cell count

Answer 21

Certain patient’s platelets form clumps when
exposed to EDTA. PLT CT= falsely decreased. WBC = falsely increase

Question 22

What is occurring in the infant that is responsible for the pathology of neonatal
alloimmune thrombocytopenia??

Answer 22

Mother’s antibody is attacking baby’s platelets

Question 23

Name this disorder: Easy bruising with recent manifestation of many bruises over most
of body. Normal PT, Normal APTT, Prolonged bleeding time, Normal platelet count and
Normal platelet aggregation studies. No history of bleeding, and has recently begun a
dietary cleanse

Answer 23

Scurvy (vitamin C deficiency – decreased synthesis of collagen

Question 24

Differentiate primary and secondary hemostasis

Answer 24

Primary – platelets aggregate and
form plug;
Secondary – fibrin develops and strengthens plug

Question 25

Delta storage pool deficiencies are cause by what defect?

Answer 25

lack of dense granules

Question 26

Gray platelet syndrome is caused by what defect

Answer 26

Lack of alpha granules in platelets
(results in hypo-granular platelets)

Question 27

Aspirin resistance may be associated with what type of hemostatic disorder?

Answer 27

thrombosis - 22% become resistant and have increased risk of thrombosing

Question 27

The capillary fragility test can be diagnostically significant in what infectious disease?

Answer 27

Dengue Fever