Background/Purpose:  Coexistence of sporadic cerebral amyloid angiopathy (CAA) and primary central nervous system vasculitis (PCNSV) has been reported, particularly in patients with granulomatous vasculitis. This condition was termed Aβ–related angiitis (ABRA).  We analyzed the clinical, radiographic, and pathological findings in a series of consecutive patients with pathologically diagnosed CAA.  We describe the clinical characteristics of the patients with ABRA and compare them with the characteristics of patients with CAA without inflammation. Furthermore, we compare the features of patients with ABRA with those of PCNSV. Methods:  We reviewed all patients seen at the Mayo Clinic, Rochester, MN over the 25 year period of 1987 to 2011, who were diagnosed pathologically with CAA. Biopsy specimens were reviewed by one pathologist (CG) without knowledge of clinical information. Patients with changes of Alzheimer’s disease were excluded. Of 74 identified patients, 46 did not show inflammation, 23 had ABRA, and 5 CAA-related inflammation (perivascular only).  We also utilized our updated cohort of 131 consecutive patients with PCNSV seen over a 25 year period of 1983 to 2007 at Mayo Clinic, Rochester, MN.  The diagnosis of PCNSV was based on brain/spinal cord biopsy or cerebral angiography, or both.  14/131 patients had ABRA. 9 additional patients with ABRA were identified between 2008 and 2011. Results:  The 23 patients with ABRA were compared with the 46 cases with CAA without inflammation. The presence of altered cognition (15/23 or 65.2% vs 41/46 or 89.1%. p = 0.017), hemiparesis (3/23 or 13% vs 18/46 or 39.1%, p = 0.026), persistent neurologic deficit or stroke (5/23 or 21.7% vs 25/46 or 54.3%, p = 0.010), and intracranial hemorrhage (2/23 or 8.7% vs 31/46 or 67.4%, p < 0.001) at presentation  were significantly less frequent in patients with ABRA than in the others. More patients with ABRA showed meningeal gadolinium enhancing lesions at MRI (13/23 or 56.5% vs 7/26 or 26.9%, p = 0.035). No differences in the demographics and cerebrospinal fluid (CSF) findings were observed in the two groups.  Survival of the patients with CAA without inflammation was significantly lower compared to that of those with ABRA.  The 23 patients with ABRA were compared to the other 117 patients with PCNSV (excluding the 14 patients with ABRA). The median age of patients with ABRA was significantly higher at diagnosis (67 years vs 47 years, p < 0.001). In ABRA patients, hemiparesis occurred less frequently at presentation (3/23 or 13% vs 51/117 or 43.6%, p =0.006), while gadolinium enhanced meningeal lesions occurred more frequently (13/23 or 56.5% vs 12/104 or 11.5%, p < 0.001). CSF abnormalities (a protein level > 700 mg/L) were observed more frequently in patients with ABRA (15/20 or 75% vs 40/90 or 47.1%, p = 0.024). The median protein CSF levels were higher in patients with ABRA (995 mg/L vs 660 mg/L, p = 0.009). No differences in the survival were observed between these 2 groups. Conclusion:  ABRA  appears to represent a condition clinically distinct from CAA and PCNSV. However, the vasculitis seems to influence the clinical findings to a greater degree than the presence of amyloid deposits in the vessels.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/a%ce%b2-related-angiitis-comparison-with-patients-with-amyloid-cerebral-angiopathy-without-inflammation/