Ventriculitis characteristics and outcomes (VELCRO): an international retrospective cohort study.

Ventriculitis is a dreaded complication of central nervous system infections, which has been scarcely described in the literature. We aimed to present a contemporary picture of ventriculitis, describing its characteristics and outcomes across the spectrum of aetiologies that may lead to ventriculitis. VELCRO is an international retrospective multicentre cohort study conducted at 34 hospitals in six countries. Adult patients fulfilling clinical, microbiological and imaging criteria of ventriculitis between 2010 and 2021 were included. Survival analyses were performed using a multivariable Cox proportional hazards regression model to identify risk factors for 1-year all-cause mortality. Overall, 436 patients with ventriculitis were included: 274 (62.8%) males, median age 58 years [interquartile range 48-68], 68 (15.6%) had diabetes mellitus and 62 (14.2%) were immunocompromised. The most common neuroimaging features of ventriculitis were ependymal enhancement (n=310/436, 71.1%), intraventricular pus (n=286/436, 65.6%) and intraventricular septations (n=85/436, 19.5%). To describe the cohort, patients were divided into three groups: ventriculitis with brain abscess(es) (V-BA, n=181), community-acquired ventriculitis without brain abscess (CA-V, n=88), and healthcare-associated ventriculitis without brain abscess (HCA-V, n=167). Intensive care unit admission was required for 351 patients (80.5%) and the median hospital length of stay was 45 days [26-74]. One-year mortality rate was 33.7% (n=147/436), with a lower rate in patients with V-BA (n=50/181, 27.6%) than in patients with CA-V (n=30/88, 34.1%) and HCA-V (n=67/167, 40.1%). On multivariable analysis, the predictive factors for 1-year mortality were: age > 60 years, immunosuppression, diabetes mellitus, Glasgow Coma Scale score < 13 at presentation, infection involving Enterobacterales or fungi, acute hydrocephalus, cerebral ischemia and intraventricular septations. Staphylococcal ventriculitis was associated with a lower 1-year mortality. Long-term unfavourable outcome (modified Rankin score (mRS) > 2 after 6 months of follow-up) occurred in 43.3% (n=91/210), considering that 26.7% (n=56) had a mRS > 2 before the onset of ventriculitis. Ventriculitis is associated with high mortality and neurological morbidity. Further large prospective studies are needed in this area of research.