AUTHOR=Scoppettuolo Pasquale , Pothen Lucie , van Maanen Aline , Onofrj Valeria , Aydin Selda , Gheysens Olivier , Lhommel Renaud , Peeters André , van Pesch Vincent , Yildiz Halil 

TITLE=Comparison between primary and secondary central nervous system vasculitis in terms of clinical, biochemical, radiological, histopathological features, and outcomes: a single-center retrospective cohort study

JOURNAL=Frontiers in Neurology

VOLUME=Volume 16 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2025.1602427

DOI=10.3389/fneur.2025.1602427

ISSN=1664-2295

ABSTRACT=IntroductionPrimary angiitis of the CNS (PACNS) is a rare inflammatory disorder affecting blood vessels of the brain and spinal cord causing acute stroke. This study aimed to describe clinical, biochemical, imaging and histopathological findings of a retrospective single-center PACNS cohort in comparison to a cohort of secondary angiitis of CNS (SACNS).MethodsAll consecutive patients diagnosed with PACNS or SACNS between 2000 and 2023 were identified using our institutional database. Univariate comparison between both groups and multivariate analysis for independent predictors was performed, as well as Receiving Operating Characteristic analysis for white blood cell count predictive of PACNS. Kaplan–Meier curves were used for evaluating survival outcomes.ResultsWe identified 20 patients in each group. PACNS patients presented more frequently with seizures (40% vs. 5%, p = 0.02) and pseudotumoral lesions (45% vs. 10%, p = 0.014). In PACNS patients, median serum WBC count at diagnosis was lower (8.4×103/mm3 [6.4–9.9] vs. 11.2×103/mm3 [9–13.6] p = 0.027) and [18F]FDG-PET/CT (p = 0.001) was negative in all cases. No significant differences were observed for lumbar puncture profiles and diffusion weighted imaging patterns. Small-vessel vasculitis with a lymphocytic pattern was the most represented histologic phenotype in both groups. Serum WBC count ≤9.93 ×103/mm3 was the only independent predictor of PACNS using multivariate analysis [OR 95%CI 5.107, (1.177–22.159)]. Both groups did not differ in terms of mortality, relapse and clinical outcome.ConclusionIn our study, PACNS patients presented more often with pseudotumoral lesions, seizures and small-vessel involvement and lymphocytic histologic pattern. WBC count ≤9.93×103/mm3 was an independent predictor of PACNS diagnosis.