Clinical and radiological features of Posterior Cortical Atrophy (PCA) in a GRN mutation carrier: a case report

Background: Posterior cortical atrophy (PCA) is a rare neurodegenerative syndrome, defined by a distinctive clinical-radiological profile, with Alzheimer's disease pathology accounting for the majority of cases. Here we present the case of a patient with impairment of visual and constructional abilities as initial manifestations.

Method: Patient underwent a multidimensional assessment, including neuropsychological evaluation, structural and functional imaging and genetic screening.

Results: Neurological and neuropsychological assessment showed an impairment of constructive and visuo-spatial skills, associated to dyscalculia, simultanagnosia, optic ataxia and oculomotor apraxia. In according to latest consensus criteria, a diagnosis of PCA was made. Coherent with clinical findings, structural and functional imaging showed a peculiar pattern of atrophy with primary involvement of right parieto-occipital cortices, whereas CSF biochemical analysis did not reveal a profile compatible with Alzheimer's pathology. Genetic screening pointed out a known pathogenic GRN mutation.

Conclusion: We present a case of PCA in a GRN mutation carrier in whom a concomitant Alzheimer's pathological process was excluded. Consequently, although lacking histological data, our case suggests GRN-related pathology causative of PCA. Through this report we want to provide further proof for a new neurodegenerative pathway leading to PCA, extending the clinical spectrum of GRN associated phenotypes.

Keywords: FDG-PET; GRN mutation; MRI; Posterior Cortical Atrophy.