Unexpected platelets elevation in a patient with idiopathic thrombocytopenia treated with oseltamivir for influenza infection.

Oseltamivir is a neuraminidase inhibitor approved for the prevention and treatment of influenza. Few haematological side effects have been reported with oseltamivir. We report herein the case of an unexpected platelet increase in a 46-year-old woman with idiopathic thrombocytopenia (ITP) treated with oseltamivir for influenza. The mechanism may involve the neuraminidase inhibition which decrease platelet surface sialic acid content and reduce their removal by the reticuloendothelial system. Oseltamivir may be responsible for platelet increase especially in patients with ITP.