The platelet count may rise above 400 as a result of:

• splenectomy
• malignant disease
• inflammatory disorders, such as rheumatoid arthritis and inflammatory bowel disease
• major surgery and haemorrhage
• myeloproliferative disorders
• iron deficiency.

Essential thrombocythaemia

Essential thrombocytosis is a myeloproliferative disorder caused by dysregulated megakaryocyte (platelet precursor) proliferation.

Epidemiology: The disease is most common in female patients aged 50-70 years old

PC

• Thrombosis (arterial or venous) - causes by a persistently elavated platelet count
• Bleeding (gastrointestinal or intracranial)
• Headache
• Dizziness/syncope (secondary to hyper-viscosity).

Signs: