Corticobasal syndrome with Balint syndrome: a clue for Alzheimer disease pathology

Context: Balint syndrome (BS), first described in 1909, has three core features: optic ataxia, oculomotor apraxia and simultanagnosia, and has been described after various conditions amongst vascular, infectious, demyelinating and degenerative diseases1 . It has already been reported concomitant with corticobasal syndrome (CBS)2 . Case report: 59 year-old male without history of previous diseases presented with behavior changes in the last two years. He had a previous diagnosis of “stroke” because frequent falls to the left side and difficulty in using his left hand for simple daily activities. After that, he gradually evolved with visual problems (bumped into objects inside his house), fear of walking or sitting, and required constant assistance for basic activities of daily living. On physical examination he presented with clear visuospatial dysfunction, characterized by simultanagnosia, oculomotor apraxia and optic ataxia. Bilateral asymmetric upper limb apraxia (worse on left side), dystonic posturing and stimulus-sensitive myoclonus in the left arm were also present. No signs of parkinsonism or language/speech disturbances were identified. Brain MRI showed severe asymmetric biparietal lobe atrophy (right more than left). DISCUSSION: The pathologic findings underlying CBS are variable, including Corticobasal Degeneration, Progressive Supranuclear Palsy, Frontotemporal Lobar Degeneration and Alzheimer Disease (AD). The association of BS and CBS favors the possibility of AD pathologic findings3 . Imaging methods like FDG-PET have recently been shown to be capable of distinguishing AD-related CBS from those associated with other pathologies4 . FDG-PET is not widely available in our country; than the presence of BS in CBS patients may individualize their treatment.