Clinical description and outcome of overall varicella-zoster virus-related organ dysfunctions admitted in intensive care units: the VAZOREA cohort study.

Background: Due to aging population and increasing part of immunocompromised patients, a raise in life-threatening organ damage related to VZV can be expected. Two retrospective studies were already conducted on VZV in ICU but focused on specific organ injury. Patients with high-risk of VZV disease still must be identified. The objective of this study was to report the clinical features and outcome of all life-threatening VZV manifestations requiring intensive care unit (ICU) admission. This retrospective cohort study was conducted in 26 French ICUs and included all adult patients with any life-threatening VZV-related event requiring ICU admission or occurring in ICU between 2010 and 2019.

Results: One-hundred nineteen patients were included with a median SOFA score of 6. One hundred eight patients (90.8%) were admitted in ICU for VZV disease, leaving 11 (9.2%) with VZV disease occurring in ICU. Sixty-one patients (51.3%) were immunocompromised. Encephalitis was the most prominent organ involvement (55.5%), followed by pneumonia (44.5%) and hepatitis (9.2%). Fifty-four patients (45.4%) received norepinephrine, 72 (60.5% of the total cohort) needed invasive mechanical ventilation, and 31 (26.3%) received renal-replacement therapy. In-hospital mortality was 36.1% and was significantly associated with three independent risk factors by multivariable logistic regression: immunosuppression, VZV disease occurring in ICU and alcohol abuse. Hierarchical clustering on principal components revealed five phenotypically distinct clusters of patients: VZV-related pneumonia, mild encephalitis, severe encephalitis in solid organ transplant recipients, encephalitis in other immunocompromised hosts and VZV disease occurring in ICU. In-hospital mortality was highly different across phenotypes, ranging from zero to 75% (p < 0.001).

Conclusion: Overall, severe VZV manifestations are associated with high mortality in the ICU, which appears to be driven by immunosuppression status rather than any specific organ involvement. Deciphering the clinical phenotypes may help clinicians identify high-risk patients and assess prognosis.