Neuropsychological assessment of Boucher-Neuhäuser syndrome: A case report

Boucher-Neuhäuser Syndrome (BNS) is a rare autosomal recessive disorder characterized by hypogonadotropic hypogonadism, spinocerebellar ataxia, and chorioretinal syndrome, and associated with a variant in the PNPLA6 gene. Although many reports have mentioned the presence of cognitive impairment, a neuropsychological assessment of a BNS case has never been published. Here, we provide a detailed description of a young adult patient with BNS who has a homozygous pathogenic variant in the PNPLA6 gene.

A 21-year-old man with progressive ataxia and a history of hypogonadotropic hypogonadism and chorioretinal dystrophy was diagnosed with BNS. A comprehensive cognitive evaluation was performed, requiring the ad hoc selection and adaption of neuropsychological tests to overcome visual and motor impairments that characterize this syndrome.

The patient presented an intact global cognitive profile with selective executive dysfunction and mild verbal reasoning dysfunction. In particular, attentional-inhibitory control, working memory, and set switching were impaired, and inadequate development of conceptual knowledge and abstract reasoning was observed.

This is the first report of an explicitly documented comprehensive neuropsychological assessment in a patient with BNS. The battery we composed is an example of a methodology that can be used to conduct a detailed cognitive examination without being penalized for physical impairment.Further studies are needed to define the typical cognitive features that characterize BNS and possibly identify its cognitive phenotype(s).