DRESS syndrome presenting with acute hypoxic respiratory failure and delayed eosinophilia

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a rare, yet life-threatening hypersensitivity reaction. It typically presents with fever, lymphadenopathy, eosinophilia and systemic organ dysfunction. Atypical presentations of DRESS syndrome, including elevated liver enzymes and acute respiratory distress syndrome, have previously been reported in rare cases. Here, we describe an otherwise healthy male patient in his mid-50s who presented with a rash, myalgia, shortness of breath and delayed eosinophilia that rapidly progressed to acute respiratory failure with hypoxia after starting trimethoprim-sulfamethoxazole. Prompt identification and treatment of atypical manifestations of DRESS syndrome is critical to reduce morbidity and mortality.