Polycythemia

Question 1

Define Polycythemia

Answer 1

An increased concentration of red cells or haemoglobin

Question 2

Describe the clinical features associated with primary polycythemia

Answer 2

1. Headache
2. Plethora(excess of a bodily fluid, esp. blood)
3. Pruritis (severe itching of the Skin)
4. Thrombosis
5. GIT bleeding
6. Splenomegaly
7. Elevated RCC (Red Cell Count)

Question 3

List the complications associated with Primary Polycythemia

Answer 3

1. Thrombosis,
   - Portal Vein Thrombosis
   - Cerebrovascular Accidents
   - Myocardial Infarction
   -Deep Vein Thrombosis
   -Pulmonaryn Emboli
2. GIT- higher incidence of Peptic Ulcers
3. Gout

Question 3

List the complications associated with Primary Polycythemia

Answer 3

1. Thrombosis,
   - Portal Vein Thrombosis
   - Cerebrovascular Accidents
   - Myocardial Infarction
   -Deep Vein Thrombosis
   -Pulmonaryn Emboli
2. GIT- higher incidence of Peptic Ulcers
3. Gout

Question 4

Describe the Laboratory Features of Primary Polycythemia

Answer 4

In the MARROW
1. Increased Erythropoiesis
2. Increased Granulopoiesis
3. Increased Megakaryopoiesis
4. In Advanced cases, there may be a degree of Myelofibrosis

Biochemically
Sp02 is normal
EPO is normal or reduced
Uric Acid concentration may be elevated
{NB:} PCR for JAK 2 mutation is positive in more than 90% of cases

Question 5

Describe the treatment of Primary Polycythemia

Answer 5

Iniatially all patients are treated with Phlebotomy, whch does not improve symptoms but normalises the Hct transiently

If that fails then for severe patients myelosuppressive agents are used, which would predispose the patient to Leukaemia

Question 6

there’s two types of secondary polycythemia, Appropriate and Inappropriate. Differenctiate between the two.

Answer 6

In appropriate polycythemia, erythropoietin levels are increased dur to hypoxia and Inapproprite polycythemia is due to inappropriate production of erythropoietin.

Question 7

Describe the pathogenesis of Appropriate secondary polycythemia.

Answer 7

High Altitude- Lows Sp02 leads to hypoxia and an increased production of EPO
Cardio-Pulmonary DIsease- leads to hypoxia and INcreased Production of EPO
Smoking Hb bound to carbon monoxide does not transport oxygen approppriately. The oxygen affinity of the remainder of the haemoglobin molecules will increase. This will result in tissue hypoxia with an increase in EPO production.
High Affinity Haemoglobinsresults in tissue hypoxia and increased Erythropoietin production.

Question 8

Describe the pathogenesis of Inappropriate secondary polycythemia

Answer 8

Familial Erythrocytosis– Inherited in an Autosomal Dominant fashion. Mutations in the EPO region.
Renal Polycythemia Solitary renal cysts, polycystic renal disease or hydronephrosis may result in the production
Neoplasms as Abberant sites of Production of Erythropoietin: Tumours which may produce excessive amounts of EPO include carcinoma of the Kidney and Hepatoma.

Question 9

Describe the differential diagnosis of polycythaemia.

Answer 9

1. Only in P vera there is a JAK 2 mutation
2. Only in P Vera there is Splenomegaly present
3. RCC, HB and Hct are increased in both P Vera and Secondary
4. WBCs and Platelets are raised in about 70% of cases and normal in secondary polycythemia unless there is infection.
5. SpO2 is normal in P Vera
6. Plasma Erythropoietin in NOT INCREASED IN PRIMARY POLYCYTHEMIA and INCREASED IN SECONDARY.