Table I.
Diagnostic criteria for common myeloproliferative disorders
| Polycythaemia Vera | Essential Thrombocythaemia | Idiopathic Myelofibrosis | |
|---|---|---|---|
| A1 Raised Red Cell mass (>25% above mean predicted value) or Hct ≥ 0.6 males; ≥ 0.56 females | A2 Absence of cause for secondary erythrocytosis | 1. Platelet Count > 600 × 109/l* | NECESSARY CRITERIA |
| A) Diffuse Bone Marrow Fibrosis | |||
| B) Absence of Philadelphia Chromosome or BCR-ABL transcript in peripheral blood cells. | |||
| A3 Palpable splenomegaly | A4 Clonality marker i.e acquired abnormal marrow karyotype | 2. No evidence of overt polycythaemia/polycythaemia masked by co-existing Iron deficiency | OPTIONAL CRITERIA |
| (i) Splenomegaly of any grade | |||
| (ii) Anisopoikilocytosis with tear drop erythrocytes | |||
| B1 Thrombocytosis (platelet count > 400 × 109/l) | B2 Neutrophil Leucocytosis (neutrophil count >10 × 109 in non smokers; >12.5 × 109 in smokers) | 3. Absence of a Philadelphia chromosome | (iii) Presence of circulating immature myeloid cells |
| 4. Absence of peripheral blood and/or marrow appearances of myelodysplasia or myelofibrosis | (iv) Presence of circulating erythroblasts | ||
| B3 Splenomegaly (demonstrated on isotope/ultrasound scanning) | B4 Characteristic BFUE growth or reduced serum erythropoietin | 5. No known cause of reactive thrombocytosis. Care should be taken to exclude iron deficiency in premenopausal women | (v) Presence of clusters of megakaryoblasts and anomalous megakaryocytes in bone marrow sections. |
| (vi) Myeloid metaplasia | |||
| Diagnosis | * In asymptomatic patients the platelet count should be observed for a period. | Diagnosis of IMF if: | |
| A1+A2+A3 or A4 establishes PV A1+A2+any 2 B Criteria establishes PV | Diagnosis is made if all above 5 criteria are met. | The two necessary criteria (designated A and B) are present with optional criteria as follows | |
| (1) any two other features if splenomegaly present | |||
| Adapted from British Committee for Standards in Haematology Guidelines on Polycythaemia36 | Adapted from diagnostic criteria in PT-1 trial coordinated by UK MPD group38. | (2) any four optional criteria when splenomegaly absent. | |
| Adapted from Italian Consensus on Diagnostic Criteria for Myelofibrosis39. | |||