Drug-Induced Hypersensitivity Syndrome/Drug Reaction With Eosinophilia and Systemic Symptoms: Predictive Score and Outcomes

BACKGROUND: We previously developed a drug-induced hypersensitivity syndrome (DIHS)/drug reaction with eosinophilia and systemic symptoms (DRESS) severity (DDS) score that may predict DIHS/DRESS-associated complications (DACs), including myocarditis, gastrointestinal bleeding, and autoimmune diseases. OBJECTIVE: To externally confirm the predictive accuracy of the DDS score, clarify its ability to identify patients at high risk of DACs and fatal outcome, and determine which treatments might reduce or increase the risk.METHODS: We conducted a nationwide multicenter retrospective study in which we followed 48 patients with DIHS/ DRESS at 5 university hospitals in Japan for 1 year after onset. Patients were divided into mild, moderate, and severe DIHS/ DRESS groups depending on their early DDS score.RESULTS: Eight cases had DACs in the severe group (n = 17); no DACs were observed in the mild group (n = 12). Receiver -operating characteristic curve analysis showed that a cutoff DDS score of double dagger 4.0 and 2.0 pound could differentiate patients who would and would not develop DACs, respectively. In the moderate-to -severe disease groups, DACs occurred only in patients who received corticosteroids and not in those who received supportive care. None of the patients who received early treatment for cytomegalovirus developed DACs. Autoimmune DACs were significantly more common in patients who received pulse corticosteroid therapy. Four deaths occurred within the 1-year follow-up; all were in patients with infectious DACs who received systemic corticosteroids.CONCLUSION: Our scoring system allows early identification of patients at increased risk for DACs. Risk factors for DACs include