Checkpoint inhibitor-associated drug reaction with eosinophilia and systemic symptom syndrome.

Drug reaction with eosinophilia and systemic symptom syndrome is a potentially fatal drug reaction that must be recognized quickly. Ipilimumab and nivolumab are both important agents in the treatment of melanoma and continue to be studied in other malignancies. We believe the mainstay of therapy for immunotherapy-induced drug reaction with eosinophilia and systemic symptom syndrome is early recognition, discontinuation of the inciting agent, supportive care, and treatment with high dose corticosteroids with appropriate tapers that may reduce the length of internal organ injury in cases with liver or kidney involvement.