Cognitive impairment as a manifestation of SPG7: case report

Hereditary spastic paraplegia (HSP) is a group of genetic disorders caused by >80 genes that can be described as either pure or complex forms.We report a case of a patient with a complex form of SPG7 with significant cognitive impairment.A 42-year-old man presented with a 10-year history of dysarthria, 5 years of gait difficulties, and 3 years of cognitive symptoms. Neuropsychological analysis showed deficits involving speed of information processing, mental flexibility, ideational fluency, verbal concept formation, visual working memory, and visual-spatial perception. Next-generation sequencing on whole blood revealed 2 heterozygous pathogenic variants in SPG7 (c. 1049_1077del, p. Pro350Glnfs*36 and c. 1529C>T, p. Ala510Val).There are emerging reports of complex forms of SPG7 presenting with impairments in memory, executive dysfunction, language, visuospatial processing, social functioning, and emotional communication. In this report, we describe a complex SPG7 patient who underwent formal neuropsychological testing to assess cognitive status in depth. This revealed deficits in speed of processing, visuospatial working memory and perception, impaired non-verbal intellect, and overall lack of insight, which have not yet been described in the literature.