PSEN2 Mutations May Mimic Frontotemporal Dementia: Two New Case Reports and a Review.

Background: Monogenic Alzheimer's disease (AD) has severe health and socioeconomic repercussions. Its rarest cause is presenilin 2 () gene mutations. We present two new cases with presumed PSEN2-AD with unusual clinical and neuroimaging findings in order to provide more information on the pathophysiology and semiology of these patients.

Brain Atrophy and Clinical Characterization of Adults With Mild Cognitive Impairment and Different Cerebrospinal Fluid Biomarker Profiles According to the AT(N) Research Framework of Alzheimer's Disease.

Introduction: This study aimed to evaluate, in adults with mild cognitive impairment (MCI), the brain atrophy that may distinguish between three AT(N) biomarker-based profiles, and to determine its clinical value.

Methods: Structural MRI (sMRI) was employed to evaluate the volume and cortical thickness differences in MCI patients with different AT(N) profiles, namely, A-T-(N)-: ; A+T-(N)-: ; and A+T+(N)+: . Sensitivity and specificity of these changes were also estimated.