Polycythemia vera
Let's break it down. Poly = many, cyto = cell, hemia = blood, so lots of cells in blood, then vera - i have no idea! Can’t find any reference to it, if anybody does please let me know!
So, this is another of the myeloproliferative disorders, it mainly affects erythroid but also myeloid and megakaryocytic cell lines, affecting those around the age of 60. PV is a philadelphia chromosome negative myeloproliferative neoplasm, deriving form a genetically transformed hematopoietic, bone marrow stem cell that results in clonal myeloproliferative. Approximately 95% of patients with PV have the JAK2 mutation which leads to erythrocytosis and often thrombocytosis, leukocytosis and splenomegaly, all helping to increase the risk of thrombosis and haemorrhage.
Patients generally present with:
- Hyperviscosity syndrome
- End organ congestion - visual disturbances, neurological symptoms, cardiac symptoms
- Reduced blood flow - recurrent thrombosis, bleeding
- Pruritus and splenomegaly
- Occasionally patients may complain of acute and burning erythema of the hands and feet (known as erythromelalgia)
Patients will have elevated Hb/Hct, JAK2 mutation, hypercellular marrow and reduced erythropoietin levels.
Image: “1901 Composition of Blood” by OpenStax College, CC BY 3.0, via Wikimedia Commons.
Management is about keeping hematocrit low, which is achieved by weekly venesections, long-term aspirin or hydroxycamide can also be given to reduce risk of thrombosis.