Potpourri

Polycythemia Vera

  • General Information
    • Polycythemia
      • Defined as increase in # RBC in the peripheral blood
      • Men Hgb >18.5 or Hct >52
      • Women Hgb > 16/5 or Hct >48
    • Relative polycythemia
      • A decrease in plasma volume that elevates the Hct or Hgb
    • Absolute polycythemia
      • Primary – mutations such as polycythemia vera, idiopathic familial polycythemia, EPO R gene mutations
      • Secondary – chronic hypoxia (high altitude, smoking, cardiac shunts, pulmonary disease, sleep apnea, EPO producing tumors (RCC, HCC, pheo, uterine fibroids), other (use of EPO injection, steroids, blood doping)
  • Symptoms
    • Indicating the hyperviscosity: chest pain, abd pain, HA, change in vision or mentation
    • Indicating polycythemia vera: post bath pruritis, erthromelalgia, gout , arterial or venous thromboses
  • Diagnosis
    • Repeat testing to avoid testing transient increases
    • History and physical considering the prior diagnoses listed, the most common cause of polycythemia is hypoxia 2/2 pulmonary disease
    • Pulse ox and ABG, CBC, UA, LFTs, CXR
    • If etiology is unclear, consider checking EPO and JAKPCV
  • Management
    • Phlebotomy: often to a goal hct below 45 for men or 42 for women.
    • Low dose ASA to reduce thrombotic complications
    • Cytoreductive therapy: i.e. hydroxyurea
    • Other therapies:
      • Interferon
      • Anagrelide (inhibits platelet maturation): PCV with secondary thrombocytosis
      • Erlotinib
      • Selective JAK2 inhibitors are being investigated