Supplementary Material for: DRESS syndrome that resembles graft versus host disease after chemotherapy in a pediatric patient: A case report

Introduction: Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a potentially life-threatening, drug-induced adverse reaction characterized by skin eruptions, lymphadenopathy, fever, and a broad range of other bodily manifestations. The spectrum of histopathologic and clinical presentations is wide; therefore, DRESS syndrome can mimic other diseases. Case Presentation: We present a case of a 4-year-old male patient who started chemotherapy with vincristine, cytarabine, and etoposide. The first clinical signs were fever, hemodynamic in-stability, and maculopapular erythema. Results: Biopsies of skin lesions were taken, and hyper-keratosis, focal parakeratosis, acanthosis with slight spongiosis, and intraepithelial dyskeratotic cells were observed. There was a perivascular lymphoid infiltrate with abundant eosinophils in the dermis, and eosinophil permeations to the acrosyringium and epithelium were found. Conclusion: DRESS syndrome is a drug-induced reaction that shares histopathological findings in skin biopsies with those seen in graft-versus-host disease. Although the histological findings are non-pathognomonic, they were characteristic enough to be of importance in the differential diagnosis.