A single-center analysis of clinical characteristics and prognosis of drug-induced hypersensitivity syndrome in adults

Background　Drug-induced hypersensitivity syndrome (DIHS) is a severe, potentially life-threatening adverse drug reaction marked by a prolonged latency period and frequent relapses, posing significant challenges for early clinical recognition. Objective　To analyze the clinical characteristics, distribution of culprit drugs, laboratory abnormalities, and prognostic factors in patients with drug-induced hypersensitivity syndrome (DIHS), so as to provide evidence for early clinical identification and treatment. Methods　This was a single-center, retrospective case series study. Clinical data were collected from patients with DIHS who were hospitalized in the Department of Dermatology, the First Medical Center of PLA General Hospital from January 2015 to December 2025. Patients with a RegiSCAR score ＞5 were defined as confirmed cases. The demographic characteristics, culprit drugs, clinical manifestations, laboratory findings, treatment, and outcomes of the patients were analyzed. Results　A total of 34 patients diagnosed with DIHS were enrolled in this study, including 16 males and 18 females, with a mean age of (43.6±16.5) years. Most patients (76.5%) were aged between 30 and 55 years. The incubation period of the disease ranged from 2 to 60 days, with a median of 21.0 (IQR, 11.0 - 30.0). d. In terms of clinical manifestations, aside from skin rash, liver function impairment had an extremely high incidence (28 cases, 82.4%). The main causative sensitizing drugs included 12 cases (35.3%) induced by antibacterial agents, 7 cases (20.6%) by traditional Chinese medicine, 5 cases (14.7%) by anti-gout drugs, and 4 cases (11.8%) by anti-epileptic drugs; in addition, 1 case was induced by an immunosuppressant and 1 case by a biological agent. Laboratory examinations revealed leukocytosis in 24 cases (70.6%) and eosinophilia in 17 cases (50.0%); concomitant viral or pathogen infections were detected as follows: cytomegalovirus infection in 14 cases (41.2%), herpes simplex virus infection in 12 cases (35.3%), Epstein-Barr virus positive infection in 11 cases (32.4%), rubella virus positive infection in 9 cases (26.5%), mycoplasma pneumoniae positive in 4 cases (11.8%), and Coxsackievirus positive in 1 case (2.9%). All patients received glucocorticoid therapy, and nearly half (16 cases, 47.1%) received combined treatment with intravenous immunoglobulin. All 34 patients achieved shortterm clinical remission after treatment, with an overall response rate of 100%; during long-term follow-up, 27 cases (79.4%) were cured and 7 cases (20.6%) experienced recurrence. The incubation period of the recurrence group was significantly longer than that of the non-recurrence group (34.9±19.0 d vs 20.2±11.4 d, P=0.015), indicating that a prolonged incubation period may be a risk factor or associated characteristic for DIHS recurrence. Conclusion　DIHS cases in our center are characterized by a relatively long latency period. Antibacterials and Chinese herbal medicines are the predominant culprit drugs, and liver function impairment is common. Early recognition, prompt withdrawal of the offending drug, and administration of systemic corticosteroids yields definite therapeutic efficacy. Viral infections may be associated with disease relapse, although the value of antiviral therapy remains to be validated. Individualized tapering of corticosteroids is emphasized.