Essential thrombocythaemia in a child of three years

Essential thrombocythaemia is a rare pathology in adults and extremely rare in children, making it a diagnostic challenge for paediatricians. The challenge is greater when patients are asymptomatic, despite an incidental discovery of thrombocytosis.We report the case of extreme thrombocytosis found in an asymptomatic child of 3 years with no personal history or familial history. Study protocol started by ruling out laboratory errors, infectious disease, haemolytic anaemia, iron deficiency anaemia and autoimmune diseases. Bone marrow sample confirmed elevated megakaryocyte production, with other cell lines within normal ranges. Genetic analysis (including JAK2 mutation) was also negative, leading to a differential diagnosis of essential thrombocythaemia. Hydroxyurea (10 mg/kg) and aspirin (5 mg/kg) were prescribed. A moderate reduction in platelet count was achieved after 4 weeks of treatment