Thrombocytosis

Question 1

REACTIVE Thrombocytosis is sitmulated by the overproduction of _____ _____ or _____

Answer 1

Stimulated by the overproduction of PRO-INFLAMMATORY CYTOKINES or TPO

Question 2

AUTONOMOUS thrombocytosis is crowth factor and cytokines independent but due to an over production of ___ by _____ ______

Answer 2

Overproduction of platelets by clinical/neoplasticism megakaryocytes.

Autonomous thrombocytosis should be considered in patients with chronic thrombocytosis, normal iron stores and an intact spleen.

Question 3

Symptoms associated with an elevated platelet count that are commonly associated with autonomous thrombocytosis

Answer 3

Vasomotor symptoms (headache, visual symptoms, acral dysesthesia)

Thrombosis

Excessive bleeding

Question 4

3 broad causes of thrombocytosis

Answer 4

1. Reactive or secondary —- associated with other medical conditions
2. Autonomous or primary— due to megakaryocytes overproduction
3. Spurious

Question 5

Causes of spurious thrombocytosis (lab artifact)

Answer 5

• cryoglobulinemia, RBC fragments from severe hemolysis, burns.
• erroneously counted as platelet by automated cell counters

Confirm true thrombocytosis with -repeat CBC and peripheral blood smear

Question 6

Low serum ferritin would indicate ____ thrombocytosis

Answer 6

Reactive thrombocytosis to iron deficiency.

Question 7

The presence of Howell-Jolly bodies, target cells and abnormal RBC morphology suggesting reduced or absen ____ function

Answer 7

Splenic function

Question 8

Dohle bodies or toxic granulation presence would indicate ____ thrombocytosis

Answer 8

qReactive thrombocytosis to an infection

Question 9

An elevated crp, esr, ferritin and fibrinogen suggest an ___ state, and indicates that the observed thrombocytosis (clotting) is ____

Answer 9

An elevated crp, esr, ferritin and fibrinogen suggest an INFLAMMATORY state, and indicates that the observed thrombocytosis (clotting) is REACTIVE

Question 10

MOST COMMON ESENTIAL thrombocythemia that can cause thrombocytosis

Answer 10

Diagnosis of exclusion: essential thrombocythemia.

May be associated with acquired VWD due to increased removal of VWF multiverses caused by adsorption to platelets.

Question 11

Clonal marker for ET

Answer 11

JAK2 V617 or NO evidence of reactive thrombocytosis

Question 12

Autonomous thrombocytosis causes

Answer 12

essential thrombocythemia

• polycythemia vera
• chronic myeloid nous leukaemia
• primary myelofibrosis
• melodyplastic syndrome

Question 13

A person has super high platelet count and a bone marrow biopsy showing megakaryocytic proliferation. There is a clinical marker JAK2 present. What’re you suspecting?

Answer 13

Essential thrombocythemia. Basically a disease the cause PLATELETTS to be formed at a high rate.

Older age is more common.splenomegaly may be seen

Question 14

General management for ET

Answer 14

Reduce thrombotic risk factors.

• ASA daily

Platelet lowering agents
- hydroxyurea, interferon.

Management of acute complications
-thrombosis- anticoagulation.
Bleeding— consider platelet transfusion, DDVAP or VWF concentrates.

Question 15

Polycythemia Vera vs essential thrombocythemia

Answer 15

In PV, there is an increase in ALL BONE MARROW PRODUCTS— often associated with thrombocytosis and leukocytes.

ET only has platelet increase but not the other cells.

Both have JAK2 presence.

Question 16

Polycythemia Vera and Essential thrombocythemia cause an increase in bone marrow products. Soon, the bone marrow can “lose steam,” producing a condition where fibrotic tissue presence starts to increased. This is called ___ ___< and is characterized by:

Answer 16

Primary myelofibrosis. Characterized by anemia, leukoerythroblastic blood smear, thrombocytosis or thrombocytoPENIA, splenomegaly, and hepatomegaly (platelets can be high or low depending on how fibrotic)

• you’d see a lot of collagen fibres in the bone marrow.

Question 17

NOTE:

— Reactive causes are most common and are cytokine or growth factor
driven

– Autonomous causes are more commonly associated with symptoms as
a result of the elevated platelet count and are due to platelet
overproduction by clonal/neoplastic megakaryocytes

Answer 17

A comprehensive history and physical exam is required to distinguish between reactive and autonomous causes.