[Diosmin-hesperidin-induced DRESS syndrome: immune reactivation by herpesvirus].

Background: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe cutaneous adverse reaction. The incidence is 1-1,000,000 with a mortality rate of 3.8-10%, and it is a disease associated with reactivation of the herpes simplex virus.

Case report: A 34-year-old woman with atopy and venous insufficiency presented with pruritic hives on her face and arms, which progressed to a morbilliform rash, facial edema, fever, lymphadenopathy, and scaling. A complete blood count showed no abnormalities: AST: 837 U/L, ALT: 11352 U/L. Due to the suspicion of DRESS syndrome, treatment with corticosteroids was initiated and a biopsy was obtained. Upon questioning, the patient reported having taken diosmin-hesperidin and undergone systemic sunscreen (Heliocare360°®) 21 days prior to the onset of the rash. Histopathological examination revealed atrophic epidermis, vacuolar degeneration, and inflammatory infiltrate. Systemic corticosteroids were administered for three weeks, with a satisfactory response. Two months later, the patient experienced reactivation of the dermatosis and hypertransaminasemia; the autoantibody panel and serology were positive for IgM for herpes simplex virus.

Conclusion: This case underscores the need to consider severe hypersensitivity reactions, even with commonly used and apparently low-risk drugs. The importance of a comprehensive approach, including identification of the suspected medication, exclusion of differential diagnoses, prolonged clinical follow-up, and surveillance for possible viral reactivation, is emphasized.