Page 219 - Essential Haematology

Chapter 15 Myeloproliferative neoplasms / 205

(a)

Figure 15.3 Polycythaemia vera: facial plethora and

conjunctival suffusion in a 63 - year - old woman.
Haemoglobin 18 g/dL; total red cell volume 45 mL/kg.
3 Splenomegaly in 75% of patients (Fig. 15.4 ).
4 Haemorrhage (e.g. gastrointestinal, uterine, cer- (b)
ebral) or thrombosis either arterial (e.g. cardiac,

Figure 15.4 Splenomegaly: enlarged spleens in
cerebral, peripheral) or venous (e.g. deep or
male patients with (a) polycythaemia vera and

superficial leg veins, cerebral, portal or hepatic
(b) myelofi brosis.
veins) are frequent.
5 Hypertension in one - third of patients.
6 Gout (as a result of raised uric acid production;

Fig. 15.5 a). 5 The bone marrow is hypercellular with trilineage
growth (panmyelosis), best assessed by a trephine
biopsy (Fig. 15.6 a).
Laboratory fi ndings

6 Serum erythropoietin is low.
1 The haemoglobin, haematocrit and red cell count 7 Plasma urate is often increased; the serum lactate

are increased. The total red cell volume (Table dehydrogenase (LDH) is normal.
15.1 ) is increased. 8 Circulating erythroid progenitors (erythroid
2 A neutrophil leucocytosis is seen in over half of colony - forming unit, CFU E , and erythroid burst -

patients, and some have increased circulating forming unit, BFU E ; see p. 16 ) are increased
basophils. compared to normal and grow in vitro independ-
3 A raised platelet count is present in about half of ently of added erythropoietin (endogenous
patients. erythroid colonies).
4 Th e JAK2 mutation is present in the bone marrow 9 Chromosome abnormalities (e.g. deletions of 9p
and peripheral blood granulocytes in over 95% or 20q) are found in a minority of subjects and
of patients. mutations in TET - 2 occur in 10 – 20%.