Intraventricular rupture of brain abscess: A two-center observational cohort study.

BACKGROUND: Intraventricular rupture of brain abscess (IVROBA) remains one of the most devastating complications of bacterial brain abscess, historically associated with high mortality rates. Early identification of measurable predictors of rupture is essential for timely intervention and improved prognosis. METHODS: We analyzed a combined retrospective-prospective cohort of 104 patients treated for brain abscesses at two tertiary Moscow hospitals (2018-2023). Demographic, clinical, and radiological variables were assessed. Microbiological profiles, management strategies, and outcomes were evaluated. Logistic regression and receiver operating characteristic (ROC) analyses determined predictors of IVROBA and unfavorable outcomes. RESULTS: IVROBA occurred in 28 patients (26.9%), representing the strongest independent predictor of mortality (adjusted odds ratio [aOR] = 14.2, p < 0.001) and poor outcome (Glasgow outcome scale 1-4). Multivariate analysis confirmed minimal distance between the abscess capsule and the ventricular wall as the predominant risk factor. Abscesses within 0-2 mm, 2-5 mm, and 5-10 mm of the ventricles had progressively higher adjusted odds of rupture (aOR = 87.2, 48.6, and 8.1, respectively; all p < 0.05) compared with those >10 mm away. Immunodeficiency was an additional independent risk factor (aOR = 9.7, p = 0.049). ROC analysis identified ≤5 mm as the optimal cutoff (area under the curve = 0.872; sensitivity 84.6%, specificity 81.2%). CONCLUSION: Proximity to the ventricular system is the principal mechanical determinant of intraventricular rupture, surpassing other clinical and radiologic variables. Abscesses within 5 mm of the ventricle should be managed aggressively, favoring early surgical drainage to prevent fatal rupture and ventriculitis.