PLATELETS: QUANTITATIVE ABNORMALITIES

Question 1

Normal platelet count

Answer 1

150 -400 x10^9/L

Question 2

Thrombocytopenia

Answer 2

50- 100 x 10^9 /L

Question 3

Spontaneous hemorrhage

Answer 3

20 x 10^9 /L

Question 4

Life-threatening hemorrhage

Answer 4

< 10 x 10^9 /L

Question 5

• Childhood and adult ITP
• Caused by an auto-Ab to the patient’s platelets.
• Most common disorder causing severe isolated thrombocytopenia.
• Treatment: Splenectomy , Corticosteroid (Prednisone) and IVIG.

Answer 5

Idiopathic thrombocytopenic purpura

Question 6

caused by an alloantibody to HPA-1a
Dx- Complement Fixation, ELISA Tx- Plasmapheresis

Answer 6

Post-transfusion purpura (PTP)

Question 7

fetal-maternal incompatibility of platelet antigens, and destruction of fetal platelets by a transplacental transfer of maternal antibody.

Answer 7

Fetal/ neonatal alloimmune thrombocytopenia

Question 8

• The drug appears to be a hapten in which antibody binds to it and will attach to the platelets.
• The binding results to platelet injury and splenic sequestration and removal of platelet which causes the thrombocytopenia.

Answer 8

Drug-Induced Immune thrombocytopenia (DIIT)

Question 9

recognized as the most common cause of DIIT.

Answer 9

Quinine

Question 10

develops secondary to antibody produced to Platelet factor 4- Heparin complex.

Answer 10

Heparin- Induced thrombocytopenia and thrombosis (HITT)

Question 11

Involves with ADAMTS 13 gene

Answer 11

Thrombotic thrombocytopenic purpura (TTP)

Question 12

An umbrella term for “taking away” a blood component. From Roman aphairesis meaning to take away by force.

Answer 12

Apheresis

Question 13

A general term used to denote the automated, selective removal of plasma. Plasmapheresis uses centrifugation to
separate the blood components, in contrast to dialysis, which uses filtration to separate small molecules from the blood.

Answer 13

Plasmapheresis

Question 14

(also called therapeutic plasma exchange [TPE]) Removal of patient plasma and replacement with another fluid (eg,
donor plasma, colloid, crystalloid)

Answer 14

Plasma exchange

Question 15

Thrombocytopenia may occur in pregnancy owing to coincidental development of the disorders mentioned earlier or due to the pregnancy itself.

Answer 15

Pregnancy-associated thrombocytopenia