Primary CNS vasculitis: A systematic review on clinical characteristics associated with abnormal biopsy and angiography.

BACKGROUND: Primary Central Nervous System Vasculitis (PCNSV) remains a diagnostic challenge due to its variable and non-specific clinical manifestations. In part, the clinical heterogeneity of PCNSV may be a consequence of the modalities used for diagnosis; accordingly, there may be different subtypes of PCNSV based on whether the diagnosis was attained by biopsy or cerebral angiography.

OBJECTIVE: To examine the frequency of symptoms, laboratory, and radiological features associated with PCNSV, and to identify distinct clinical features between biopsy and angiography defined PCNSV.

METHODS: We conducted a systematic review of articles published in the English language from 1991 to 2019 that met all diagnostic criteria of PCNSV.

RESULTS: We identified 55 studies, reporting on 907 PCNSV cases. Median age was 45 (IQR 50-36), and 53% were women. Biopsy compared to angiography defined PCNSV had a higher percentage of cognitive impairment, and seizures on initial presentation, and were more likely to have a subacute or progressive onset, abnormal CSF profile, small vessel involvement on angiography, and tumor-like lesions and gadolinium enhancement on MRI. Angiography defined PCNSV were more likely to have an acute onset, focal weakness and visual impairment on initial presentation, medium vessel involvement on angiography, and infarcts on MRI. Brain biopsy was diagnostic of PCNSV in 71% of cases, and demonstrated an alternative diagnosis in 37% of cases, the most common being infection (19%) and lymphoproliferative disease (18%).

CONCLUSIONS: This study provides further evidence that there are distinct clinical features between biopsy and angiography defined PCNSV, which may aid in selecting patients for appropriate invasive tests.