Introduction: Varicella pneumonia is the most frequent and severe complication of varicella infection in adults, associated with a mortality of 30%.
Case Report: A 46-year-old female with ulcerative colitis that starts fever, increasing dyspnea and a generalized rash with vesicles two days after admission. Laboratory tests showed renal impairment, acute hepatitis, a highly inflammatory state and chest radiography shows bilateral shadows with a rapid clinical deteriorating despite the anticipated treatment with antibiotic. 24-hours after the first symptoms, she develops an acute respiratory distress syndrome and was admitted to the intensive unit care and initiated protective lung ventilation. Despite acyclovir treatment and ventilator strategy, she maintained severe hypoxemia and need to started extracorporeal membrane oxygenator venovenous (ECMO-vv). The lavage fluid polymerase-chain reaction and vesicular liquid returned highly positive for varicella zoster virus (VZV) and completed treatment for seven days. The patient maintained ECMO-vv during nine days, was extubated after 13 days of mechanical ventilation, with all dysfunctions resolved.
Conclusion: We can conclude that systemic varicella zoster virus infection, although rare, can cause serious and fatal complications. Early detection and proper treatment is mandatory for minimizing mortality and controlling infection, but often difficult because typical dermatological findings and the elevation of specific antibodies

Keywords: Acute respiratory distress syndrome, Acyclovir, Pneumonia, Varicella