Inflammatory Episode in a Patient With Probable Iatrogenic Cerebral Amyloid Angiopathy: An ARIA Before the Storm?

INTRODUCTION: Amyloid related imaging abnormalities effusion/edema (ARIA-E) is seen in patients treated with antiamyloid antibodies. It resembles cerebral amyloid angiopathy (CAA) related inflammation (CAA-ri) caused by an inflammatory response to amyloid deposition in the walls of cortical and leptomeningeal vessels in patients with sporadic CAA. Recently, temporary inflammatory imaging findings that remained clinically silent have been described in patients with iatrogenic CAA (iCAA). RESULTS: We describe a case of probable iatrogenic CAA (iCAA), which demonstrated radiological features of CAA-ri that remained clinically silent and spontaneously resolved before the inaugural intracranial hemorrhage. Clinical and radiological features resembled ARIA-E. DISCUSSION: This case adds to the clinical and radiological spectrum of iCAA and suggests an immune-mediated response to amyloid deposition.