Fulminant Leptomeningitis Without Hemorrhagic Lesions as an Atypical Initial Presentation of Cerebral Amyloid Angiopathy-Related Inflammation.

Cerebral amyloid angiopathy related inflammation (CAA-ri) is a rare neuroinflammatory condition that may present with a wide spectrum of clinical and radiographic findings. Classic imaging features include areas of asymmetric subcortical white matter hyperintensities due to vasogenic edema, together with the classic hemorrhagic lesions of cerebral amyloid angiopathy (CAA) including microhemorrhages, superficial siderosis, or convexity subarachnoid hemorrhage. We describe a case of CAA-ri appearing as fulminant leptomeningitis without other obvious radiographic features of CAA at presentation.