This document discusses polycythemia, which is characterized by an increased red blood cell mass. It can be absolute, due to increased red cell volume, or relative, due to decreased plasma volume. Causes of absolute polycythemia include primary polycythemia vera, which results from a clonal stem cell mutation, and secondary polycythemia, which is usually appropriate and resolves when the underlying cause is treated. Clinical findings of polycythemia vera include reddening of the skin and risk of blood clots. Treatment aims to maintain a normal blood count through phlebotomy, medications, or splenectomy.

1. Done by : Ala’a Abdullah
Polycythemia
Supervised by : Dr.Tariq Aladily

2. Polycythemia
• Polycythemia or erythrocytosis is characterized by an increase in the red cell
mass, measured as increased hemoglobin and hematocrit above the upper limit of
normal for the patient’s age and sex.
• Polycythemia is classified into:
 Absolute polycythemia (red cell mass (volume) is raised), which is
subdivided into primary and secondary polycythemia.
 Relative or pseudopolycythemia (red cell volume is normal but the plasma
volume is reduced ).

3. Causes of polycythemia veraCauses of absolute polycythemia
Primary
Polycythemia ( rubra ) vera
Secondary
Caused by physiologically appropriate
erythropoietin increase in :
 High altitudes
 Pulmonary disease and alveolar
hypoventilation (sleep apnea)
 Cardiovascular disease , especially
congenital with the cyanosis
 Increased affinity haemoglobin Familial
(congenital) polycythemia
 Heavy cigarette smoking
Caused by inappropriate erythropoietin
increase in :
 Renal cancer
 Tumors such as uterine , hepatocellular
carcinoma

4. Secondary polycythemia
• Secondary polycythemia is an increase in red cell mass due to some other
conditions. It resolves when the underlying cause is treated.
• It is due to increased erythropoietin effect, which may be either
physiologically appropriate (due to tissue hypoxemia) or physiologically
inappropriate (due to neoplasms, renal cysts, exogenous erythropoietin, androgen
excess).
• Causes of secondary polycythemia:
 High altitudes
 Pulmonary disease and alveolar hypoventilation
 Cardiovascular disease , especially congenital with the cyanosis
 Increased affinity haemoglobin (familial polycythaemia)
 Heavy cigarette smoking
 Renal cancer
 Tumors such as uterine , hepatocellular carcinoma

5. • This is a rare autosomal dominant condition.
• Caused by mutations in the EPO receptor gene which result in hypersenstivity to
erythropoiten.
• This hematological disorder is present at birth but the clinical symptoms, if they
develop, can be discovered at any time during childhood or adulthood.
familial (congenital) polycythemia

6. Relative polycythemia
• It is the result of plasma volume contraction, which means a normal TRCV (Total
Red Cell Volume).
• It is far more common than Polycythemia vera.
• Patients with chronic relative erythrocytosis have been described as having
Gaisböck syndrome, stress erythrocytosis, pseudopolycythemia (In this syndrome,
primarily occurring in obese men, hypertension causes a reduction in plasma
volume, resulting in a relative increase in red blood cell count).
• Causes of relative polycythemia:
 Stress
 Cigarette smoking
 Dehydration: water deprivation, vomiting
 Plasma loss: burns, enteropathy

7. Primary Polycythemia (rubra) vera
• Polycythaemia rubra vera (PRV), also known as polycythaemia vera and primary
proliferative polycythaemia, is a myeloproliferative disorder in which there is
increased production of red cells and sometimes also of granulocytes and platelets.
• In PRV, the increase in red cell volume is caused by a clonal malignancy of marrow
stem cell.
• The disease results from somatic mutation of a single haemopoietic stem cell which
gives it’s progeny a proliferative advantage .
• The JAK2 mutation is present in haemopoietic cells in almost 100% of patients.
• Polycythaemia vera is a rare chronic disease diagnosed in an estimated 2 to 3 people
per 100,000 population. Although it can occur at any age, polycythaemia vera
usually affects older people, with most patients diagnosed over the age of 55 years.
Polycythaemia vera is rare in children and young adults. It occurs more commonly
in males than in females.

8. Clinical Findings
Clinical features are the result of hyperviscosity , hypervolaemia or hypermetabolism:
• reddening, swelling, and pain in the digits.
• Headaches, dyspnea, numbness or tingling in the fingers.
• Blurred vision and night sweats.
• Redness of the skin especially the face, may look red, ruddy cyanosis.
• Weight loss.
• Hypertension.

9. Complications
Possible complications of polycythemia vera include:
 Blood clots - Polycythemia vera causes an increase in blood thickness
and decrease in blood flow, as well as abnormalities in the platelets, and
this increase the risk of blood clots. Blood clots can cause a stroke, a heart
attack, or blockage of an artery in the lungs (pulmonary embolism) or in
a vein deep within a muscle (deep vein thrombosis). It is the major cause
of death in 10-40% of patients.
 Blood clots may also block blood vessels that drain blood from the
liver (Budd-Chiari syndrome).

10. Complications
(cont.)
 Skin problems - Polycythemia vera may cause the skin to itch, especially after a
warm bath or shower, due to releasing histamine from basophiles. A burning or
tingling sensation in the skin may be experienced. The skin may also appear red,
especially on the face, palms and ear lobes.
 Problems due to high levels of RBCs – this may cause open sores on the inside
lining of the stomach, upper small intestine or esophagus (peptic ulcers),
inflammation in the joints (gout), and uric acid stones in the kidneys.
 Enlarged spleen (splenomegaly) - The increased number of blood cells caused
by polycythemia vera makes the spleen work harder than normal, which causes
it to enlarge. If the spleen becomes too large, it may need to be removed.

11. Laboratory findings
• The haemoglobin , haematocrit and red cell count are increased
(The hemoglobin may range from ~18 to 24 g/dL in male and ~ 16 to
22 g/dl in female; the hematocrit is usually >60% in men and >55%
in women).
• A neutrophil leukocytosis is seen in over half of patients , and some
have increased circulating basophils. a raised platelets count is
present in about half of the patients.
• The JAK2 mutation is present in the bone marrow and peripheral
blood granulocytes in nearly 100% of patients.
• The neutrophil alkaline phosphatase (NAP) score is usually
increased.

12. Laboratory findings
(Cont.)
• The bone marrow is hypercellular with prominent megakaryocytes , best assessed
by a trephine biopsy.
• Serum erythropoietin usually low in polycythemia vera but high in erthrocytosis
(secondry).
• Blood viscosity is increased.
• Plasma urate is often increased , the serum lactate dehydrogenase ( LDH) is normal
to slightly increased.
• Circulating erythroid progenitors ( erythroid colony –forming unit , CFU-E &
erythroid burst – forming BFU-E) are increased.

14. Blood film
• The peripheral blood film in polycythaemia of any etiology shows a ‘packed film’
appearance since the viscosity of the blood means that the film of blood is not
spread as thinly as normal.
• The WBC, neutrophil and basophil counts are increased in the majority of cases.
Monocyte and eosinophil counts are much less often increased.
• The platelet count is elevated in about two-thirds of cases and platelet size is
increased. Giant platelets or megakaryocyte fragments may be present.
Bone Marrow
• The bone marrow is hypercellular. There is an increase in all cell lines, with a
predominant increase in erythroid precursors, resulting in a decrease in the ratio of
myeloid to erythroid cells (M:E ratio).
• Mild fibrosis is present in ~10 to 15% of cases.
• Absence of stainable iron in the marrow.

15. ‘packed film’ consequent on post-transplant polycythaemia. The Hb
was 20 g/dl and the Hct 0.59. The MCV was increased to 114 fl.

16. The blood film of a patient with PRV complicated by iron deficiency,
showing anaemia and thrombocytosis and some hypochromic and
microcytic cells. There was an increased basophil count and there is one
basophil in the field.

17. Polycythaemia Rubra Vera; hypercellular
bone marrow trephine
Polycythemia Vera; a giant platelet.
Erythrocytes show signs of hypochromia

18. Criteria for diagnosis of polycythaemia (rubra) vera
Category A ( major ) Category B ( minor )
Elevated red cell mass
JAK2 mutation
Hypercellular bone marrow
Low erythropoietin ( EPO )
Splenomegaly

19. Treatment
• Treatment is aimed at maintaining a normal blood count.
• The haematocrit should be maintained at about 0.45 and the platelet
count below 400*10^9/L.
• Venesection or phlebotomy – to reduce the hematocrit to less than
0.45, useful when a rapid reduction of red cell volume is required.
However, it does not control the platelet count.
• Cytotoxic myelosuppression – considered if there is poor tolerance
of venesection, progressive spleenomegaly, thrombocytosis, weight
loss or night sweats.

20. • Hydroxyurea is valuable in controlling the blood count and may
need to be continued for many years.
• Phosphorus- 32 therapy – is the most effective myelosupressive
agent, and is only used for older patients with severe disease.
• Interferone - suppresses excess proliferation in the marrow,
valuable in controlling itching and it is the first-line drug for patients
less than 40 yrs old.
• Aspirin – reduces thrombotic complications.

21. Polycythaemia in neonates
• Most cases of polycythaemia occur in normal healthy infants and may result from a variety
of reasons.
 Causes of polycythaemia:
1. Placental red cell transfusion may be caused by :
• delayed cord clamping which may increase blood volume and red cell mass
• twin to twin transfusion syndrome, is a complication of unequal placental sharing ( single
placenta )
2. Placental insufficiency with increased fetal erythropoiesis secondary to intra-uterine hypoxia
• Placental insufficiency may occur in association with :
• Small for gestational age infants
• post mature infants
 Other causes of polycythaemia include:
• maternal substance use eg. smoking
• maternal diabetes
• large for gestational age infant
• chromosomal abnormality ( down syndrome )

22. A pair of newborn twins affected by TTTS. Both the recipient (left) and
donor (right) survived

23.  Signs and symptoms
• Many polycythaemic infants are asymptomatic. When present, the signs and
symptoms of polycythaemia are non-specific and include:
• feeding problem
• plethora
• laziness
• cyanosis
• respiratory distress
• hypotonia
• Hypoglycaemia
• Jaundice
• hypocalcaemia
• Thrombocytopenia
• Investigation for polycythaemia :
The diagnosis of polycythaemia is made on central or peripheral venous blood with
a haematocrit over 65%.

24. Treatment
 Treatment for polycythaemia :
• partial exchange transfusion (PET) to reduce the venous haematocrit below 60%.
• PET using normal saline as the replacement fluid is recommended in symptomatic
infants with a haematocrit above 70%.
• PET is best performed thorugh peripheral arterial and venous lines.

25. Thank you