Polycythemia Vera and Secondary Polycythemia

Question 1

What is erythrocytosis?

Answer 1

Red blood cell count above normal range

Question 2

Define true/absolute erythrocytosis polycythemia.

Answer 2

Increase in red cells, which causes increased haematocrit and Hb concentration

Question 3

What is apparent polycythemia?

Answer 3

Red cell numbers are normal but are more concentrated due to less plasma

Question 4

True or False: Apparent polycythemia results in increased haematocrit and Hb concentration.

Answer 4

True

Question 5

What characterizes polycythemia vera?

Answer 5

Rare myeloproliferative cancer originating in bone marrow due to JAK2 mutation

Question 6

At what age is polycythemia vera typically diagnosed?

Answer 6

After 60 years old

Question 7

Who is more likely to develop polycythemia vera?

Answer 7

More common in men than women
Individuals with Jewish ancestry
History of Budd-Chiari syndrome

Question 8

What is secondary polycythemia?

Answer 8

Overproduction of erythrocytes due to chronic hypoxia triggering increased EPO synthesis

Question 9

Can secondary polycythemia occur at any age?

Answer 9

Yes

Question 10

What is the primary cause of polycythemia vera?

Answer 10

JAK2 point mutation causing neoplastic proliferation of hematopoietic progenitor cells

Question 11

List some risk factors for secondary polycythemia.

Answer 11

• Generalised hypoxia due to smoking, lung/cardiac disease, CO poisoning, high altitudes
• Renal hypoxia due to CKD
• Increased EPO production due to tumours
• Doping/medication with anabolic steroids, EPO, testosterone, diuretics
• Genetic mutations that upregulate EPO or code for hemoglobin variant with higher oxygen affinity

Question 12

What triggers increased EPO synthesis in chronic hypoxia?

Answer 12

Commonly due to conditions like chronic lung disease or living at high altitudes

Question 13

What is physiological polycythemia?

Answer 13

Form of secondary polycythemia caused by living at high altitudes

Question 14

Fill in the blank: Polycythemia vera is characterized by the overproduction of _______.

Answer 14

[erythrocytes]

Question 15

What are the clinical features of Polycythemia Vera?

Answer 15

Facial plethora, splenomegaly, gouty tophi, pruritus after warm water contact, fatigue, dizziness, neurological symptoms, GI symptoms.

Examples include swelling and puffiness with red/brown discoloration, early satiety, and discomfort.

Question 16

What are the complications associated with Polycythemia Vera?

Answer 16

Increased risk of thrombosis, major hemorrhage, progression to myelofibrosis or AML.

Thrombosis can lead to cardiovascular events such as stroke or heart attack.

Question 17

What investigations are used for Polycythemia Vera?

Answer 17

Bone marrow biopsy, FBC, JAK2 mutation test, serum EPO level.

Bone marrow biopsy shows hyperplasia of erythroid, granulocytic, and megakaryocytic lineages.

Question 18

What findings are expected in FBC for Polycythemia Vera?

Answer 18

Erythrocytosis, leukocytosis, thrombocytosis, high hematocrit.

Question 19

What are the clinical features of Secondary Polycythemia?

Answer 19

Abdominal mass, hypertension, cyanosis, nail clubbing, fatigue, dizziness, neurological symptoms, GI symptoms.

Abdominal mass could indicate EPO-secreting tumors.

Question 20

What investigations are used for Secondary Polycythemia?

Answer 20

FBC, LFTs, U&Es, serum EPO level, ECGs, chest X-ray.

FBC shows erythrocytosis and high hematocrit; serum EPO level is increased.

Question 21

What is a common laboratory finding in Secondary Polycythemia?

Answer 21

Increased serum EPO level and elevated serum uric acid.

Question 22

What is the first-line treatment for Polycythemia Vera?

Answer 22

Hydroxycarbamide/hydroxyurea or interferons (chemotherapy) and aspirin

Question 23

What is the second-line treatment for Polycythemia Vera?

Answer 23

The alternate first-line drug and aspirin, e.g., interferon is better for younger patients and pregnant women

Question 24

What are the third-line treatments for Polycythemia Vera?

Answer 24

Anagrelide (inhibits megakaryocyte maturation but increases risk of thrombotic and bleeding events) or ruxolitinib (JAK2 inhibitor)

Question 25

What additional procedure can be added to the treatment of Polycythemia Vera?

Answer 25

Venesection/phlebotomy (removing ~0.5 litres blood from a vein in the arm)

Question 26

How should secondary polycythemia be managed?

Answer 26

Treat the underlying cause