Objective:

To assess if a combination of clinical, cerebrospinal fluid (CSF), and quantitative vessel-wall magnetic resonance imaging (VWMRI) markers can predict Primary Angiitis of the Central Nervous System (PACNS) with and without brain biopsy. 

Background:

Without brain biopsy, there are limited diagnostic predictors to differentiate PACNS from non-inflammatory cerebral vasculopathy.

Design/Methods:

In this cross-sectional study, we reviewed electronic medical records to identify patients (≥18 years old) who presented to our medical center between 01/2015 and 12/2021 with ischemic stroke due to biopsy-proven PACNS and probable PACNS (not-biopsy proven).  For the comparison group, we identified patients with non-inflammatory vasculopathy with intracranial atherosclerotic disease (ICAD).  Patients with no CSF or VWMRI data were excluded. Using logistic regression models in primary and sensitivity analyses, we assessed the diagnostic value of clinical, CSF and quantitative VWMRI variables in predicting PACNS in patients with and without brain biopsy.

Results:

Twenty-seven (45.8%) PACNS patients and thirty-two (54.2%) ICAD patients (54ꞏ2%) met the study inclusion criteria. Twenty-four (75%) ICAD patients and 6 (22ꞏ2%) biopsy-proven PACNS patients showed large vessel involvement and were included in the primary analysis. Encephalopathy (odds ratio [OR], 7ꞏ60; 95% confidence interval [CI], 1ꞏ07-54ꞏ09) and seizure (OR 23ꞏ00; 95% CI, 1ꞏ77-298ꞏ45) were significantly associated with PACNS. All patients were included in the sensitivity analysis, in which headache significantly predicted PACNS (OR 7ꞏ60; 95% CI, 1ꞏ07-54ꞏ09). In the primary analysis, for every 1 WBC/uL increase in CSF, there was a 47% higher odds of PACNS (OR 1ꞏ47; 95% CI, 1ꞏ04-2ꞏ07). On VWMRI, a C/E ratio >1 (OR 115ꞏ00; 95% CI, 6ꞏ11-2165ꞏ95), percent concentricity ≥50% (OR 55ꞏ00; 95% CI, 4ꞏ13-732ꞏ71), and percent irregularity <50% (OR 55ꞏ00; 95% CI, 4ꞏ13-732ꞏ71) indicated a significantly higher odds of PACNS compared to ICAD.

Conclusions:

Quantitative VWMRI metrics, CSF pleocytosis, and clinical features of encephalopathy, seizure, and headache significantly predict a diagnosis of probable PACNS.