Abstract: Objective: To analyze the clinical characteristics of adult patients with severe varicella, and enhance the understanding of this disease. Methods: The clinical data of 18 patients with severe varicella admitted to our hospital from January 2018 to March 2024 were retrospectively analyzed. Results: Of the 18 patients, 12 were males and 6 were females. The average age was 32.1 years (ranging from 18 to 50). Nine patients (50.0%) received long-term immunosuppressive drugs due to organ transplantation, rheumatoid arthritis, or other underlying diseases. Multiple laboratory abnormalities included decreased platelet count (12 cases, 66.7%), elevated liver enzyme (15 cases, 83.3%), elevated myocardial enzyme (18 cases, 100%), elevated NT-pro BNP(15 cases, 83.3%), elevated D-dimer(16 cases, 88.9%), and elevated procalcitonin(14 cases, 77.8%). Six patients(33.3%) discontinued treatment due to poor outcomes, of them, 3 cases died. There were 15 patients infected with pneumonia, and 11 patients had type Ⅰ respiratory failure. Conclusions: Severe varicella is more prevalent in adult males, and has a relatively high mortality rate. Immunocompromised adults are at higher risk for severe varicella infection. Type Ⅰ respiratory failure is frequently observed in adults with severe varicella complicated with pulmonary infection.

Key words: severe varicella, adult, varicella-zoster virus, pneumonia