Absolute polycythemia classification
Primary (low EPO)
Acquired:
Polycythemia vera
Primary (low EPO)
Acquired:
Polycythemia vera
Congenital:
Primary familial polycythemia, AD, EPOR mut
Secondary (high EPO)
Acquired:
Increased physiological erythropoietin (EPO) production: decreased oxygen loading: hypoxia, high altitude; pulmonary disease; cyanotic heart disease; carboxyhemoglobinemia
EPO-secreting tumors or kidney diseases: Wilms' tumor, renal carcinoma; cerebellar hemangioma; hepatoma, polycystic kidney; renal artery stenosis
Decreased oxygen unloading: methemoglobinemia (cyanosis)
Congenital:
Decreased oxygen unloading:
1. high oxygen affinity hemoglobinopathy, AD, ( may not be detected by electrophoresis)
2. bisphosphoglycerate mutase deficiency, AR, decreased 2,3-DPG;
3. hemoglobin M, AD, cyanosis
4. congenital methemoglobinemia due to cytochrome b5 reductase deficiency, AR, cyanosis
Altered oxygen sensing, dysregulated pVHL/PHD/HIF system with increased EPO:
Chuvash polycythemia: AR, VHL mut, HIF2a increased and EPO increased, also pulmonary hypertension, no risk for tumor
PHD2 erythrocytosis: AD, loss-of-function mutations in PHD2 gene, increased HIF
HIF2α erythrocytosis: AD, Gain-of-function mutations, increased HIF activity
Pt's EPO: 9.5 mU/ml (within the reference range)
JAK2 mut: negative
Family history indicates a AD transmission. Normal EPO favors primary polycythemia.
Diagnosis: Pending more testing results. To be followed up.
Primary familial polycythemia, AD, EPOR mut
Secondary (high EPO)
Acquired:
Increased physiological erythropoietin (EPO) production: decreased oxygen loading: hypoxia, high altitude; pulmonary disease; cyanotic heart disease; carboxyhemoglobinemia
EPO-secreting tumors or kidney diseases: Wilms' tumor, renal carcinoma; cerebellar hemangioma; hepatoma, polycystic kidney; renal artery stenosis
Decreased oxygen unloading: methemoglobinemia (cyanosis)
Congenital:
Decreased oxygen unloading:
1. high oxygen affinity hemoglobinopathy, AD, ( may not be detected by electrophoresis)
2. bisphosphoglycerate mutase deficiency, AR, decreased 2,3-DPG;
3. hemoglobin M, AD, cyanosis
4. congenital methemoglobinemia due to cytochrome b5 reductase deficiency, AR, cyanosis
Altered oxygen sensing, dysregulated pVHL/PHD/HIF system with increased EPO:
Chuvash polycythemia: AR, VHL mut, HIF2a increased and EPO increased, also pulmonary hypertension, no risk for tumor
PHD2 erythrocytosis: AD, loss-of-function mutations in PHD2 gene, increased HIF
HIF2α erythrocytosis: AD, Gain-of-function mutations, increased HIF activity
Pt's EPO: 9.5 mU/ml (within the reference range)
JAK2 mut: negative
Family history indicates a AD transmission. Normal EPO favors primary polycythemia.
Diagnosis: Pending more testing results. To be followed up.