Eltrombopag-Induced Near-Fatal Hyperammonemic Encephalopathy – Case Report

An 8-year-old girl with chronic immune thrombocytopenic purpura treated with eltrombopag presented with lactic acidosis and severe hyperammonemic encephalopathy necessitating hemofiltration.Genetic metabolic disorders associated with hyperammonemia were excluded.Despite standard dosing, supratherapeutic plasma levels of eltrombopag were found, suggesting an adverse drug effect due to drug accumulation.Awareness of hyperammonemia as adverse reaction to eltrombopag is warranted.Close monitoring of transaminases is required in children and therapeutic drug monitoring could aid in tailoring effective treatment doses for children to mitigate risk in populations that are more susceptible to complications.