Eltrombopag Dose Adjustment During Infection-Induced Thrombocytosis in a Patient With Chronic Idiopathic Thrombocytopenic Purpura.

Idiopathic thrombocytopenic purpura (ITP) is an immune disorder in which antibodies attack platelets, leading to platelet destruction and increased bleeding risk. Standard treatment is to maintain a platelet count sufficient to mitigate the bleeding risk. First-line therapies include steroids and IV immunoglobulins, and second-line therapy includes thrombopoietin receptor agonists like eltrombopag in combination with other medications (e.g., rituximab) to reduce immune attack. Eltrombopag is a nonpeptide oral thrombopoietin (TPO)-receptor agonist that increases platelet counts by binding to and activating the human TPO receptor. While using eltrombopag, the target platelet count range is usually between 50,000/mm³ and 200,000/mm³, so the dose should be adjusted accordingly. However, this dose adjustment is based on platelet count increments in response to eltrombopag administration. Adjusting the dose when the platelet count is elevated due to a different factor can be challenging. Data are not yet available on whether stopping the treatment or reducing the dose will harm the patient or result in an acute drop in platelet count and increased bleeding. We present the case of a 60-year-old woman with ITP on a stable eltrombopag regimen who completed an eltrombopag-free period after developing infection-induced thrombocytosis.