Thrombocythaemia (essential)

Last updated: Saturday, 15, January, 2011
PresentationAppropriate Tests

Essential thrombocythaemia is a myeloproliferative disorder in which the haemopoietic stem cell proliferation leads to a predominant increase in platelet numbers, usually with neutrophilia. 

FBC, blood film; bone marrow aspiration and trephine biopsy.

JAK-2 mutation may be positive in 50% pts with ET.

See also Myeloproliferative disorders



  • Splenic infarction

Thrombosis (arterial or venous)



May be from a local lesion.

Platelet dysfunction

Variable abnormalities of platelet function have been described. The bleeding time does not predict spontaneous or surgical bleeding and is not indicated.

Acquired von Willebrand's disease


  • Cytotoxic therapy
  • Disease progression/transformation

Anaemia, especially

Disease progression/transformation to