Corticosteroid Treatment Guided by Peripheral Blood Mononuclear Cell Counts in Cerebral Amyloid Angiopathy-related Inflammation: A Case Report

Abstract

Background: Cerebral amyloid angiopathy-related inflammation (CAA-I), a rare variant of cerebral amyloid angiopathy, is one of treatable causes of rapidly progressive dementia. CAA-I usually occurs in the elderly and corticosteroids are most often used for treatment. Thus it is more necessary to develop an individualized dosing regimen to maximize efficacy yet minimize adverse effects of corticosteroids. We report a CAA-I patient successfully treated by corticosteroid therapy guided by dynamic monitoring of peripheral blood mononuclear cell (PBMC) count. Case presentation: A 68-year-old female presented with subacute step-wise cognitive decline. Medical history and current examination revealed multiple risk factors for cerebral amyloid angiopathy, including apolipoprotein E ε4/ε4 genotype, hyperhomocysteinemia, hypertension, and chronic renal failure, while brain susceptibility-weighted magnetic resonance imaging revealed diffuse lobar microbleeds associated with extensive lesions disturbed throughout cerebral grey and white matter on T1- and T2-weighted MRI. The CD19+ B-cell fraction of PBMCs was markedly elevated, as were inflammatory markers such as erythrocyte sedimentation rate and C-reactive protein. Cerebrospinal fluid total protein and T-tau levels were also elevated, while Aβ42 was low and P-tau levels were normal. Corticosteroid treatment guided by dynamic CD19+ B-cell number monitoring reversed these inflammatory signs, imaging manifestations, and acute cognitive decline. Conclusions: Corticosteroid treatment individualized by dynamic monitoring of PBMC CD19+ B-cell fraction may provide for maximum therapeutic efficacy with minimal adverse effects in patients with CAA-I.