To evaluate the prevalence and clinical progression of cerebral amyloid angiopathy-related inflammation (CAA-RI).

CAA-RI is an autoimmune perivascular inflammatory response to cerebral amyloid angiopathy. The clinical course and optimal management of this disorder is not well established.

Electronic records of patients with suspected cerebral amyloid angiopathy treated at a single tertiary care center from 1/2010 – 12/2013 were reviewed. Inclusion criteria included possible or probable CAA by modified Boston criteria, available MRI with hemosiderin sensitive (SWI, T2*, or GRE) and T2/FLAIR sequences, with findings radiographically suggestive of CAA-RI as agreed upon by two independent vascular neurologists. Clinical course, imaging findings, and outcomes were reviewed and reported.

A total of 13 patients met imaging criteria compatible with CAA-RI. The median age (interquartile range) at time of first MRI consistent with CAA-RI was 75 (69-80). Two (15%) patients were male, ten (77%) were Caucasian, and two (15%) were African American. The most common presenting symptom at the time of first MRI was cognitive change (77%), macrohemorrhage (62%), seizure/epileptiform discharges (31%), headache (31%), transient neurological symptoms (31%), and ischemic stroke (15%). Of the 13 patients with radiographic features of CAA-RI, only three (23%) were clinically identified by the treating physician, while 77% remained undiagnosed. Of the three that received a formal diagnosis, only one was diagnosed at time of the earliest MRI and treated with steroids, while the other two patients were diagnosed later in the course of their disease (21 and 28 months respectively) and neither were treated. Nine (69%) patients died with median time to death from first MRI of 1.5 years (0.75-4.25).

CAA-RI is an often under-recognized and under-treated condition. This may be due to its highly variable clinical presentation and subclinical progression. Prospective studies are needed to better characterize this condition.