Drug-induced hypersensitivity syndrome(DiHS), often referred to as drug reaction with eosinophilia and systemic symptoms (DRESS), is a life-threatening multi-organ system reaction induced by drugs and associated with sequential reactivations of herpesviruses. This syndrome has several unique features, creating uncertainty over whether it represents true drug eruption. Areas covered: A literature review of all the cases was made by a Pub Med search. The delayed onset, paradoxical worsening of clinical symptoms after withdrawal of the causative drug and unexplained cross-reactivity to multiple drugs are unique features of this syndrome, which could prompt infection to be an initial consideration. Regulatory T cells (Tregs) are expanded at the acute stage but, upon clinical resolution, their function become gradually defective. Because such a gradual loss of Treg function occurring after resolution of DiHS/DRESS could increase the risk of developing autoimmune sequelae, systemic corticosteroids administered during the acute stage may serve to prevent not only tissue damage but also the gradual loss of Treg function by restoring the impaired Treg activity. Expert opinion: Systemic corticosteroids give promising results in terms of not only alleviating a variety of clinical symptoms at the acute stage but also of preventing the generation of autoimmune responses occurring at the resolution stage.
Keywords: Drug eruption; drug reaction with eosinophilia and systemic symptoms; drug-induced hypersensitivity syndrome; regulatory T cells.