Prevalence of Autism Spectrum Disorder symptoms in children with neurofibromatosis type 1.

Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic condition. While considerable work has focused on cognitive functioning, several research groups also observed difficulties in social functioning as a prominent feature of NF1. These problems and the possible link between NF1 and Autism Spectrum Disorder (ASD) have become increasingly important in recent NF1 literature. The aim of the current study was to assess ASD characteristics in a hospital-based NF1 pediatric population (n = 82) using the standardized Children Social Behavior Questionnaire (CSBQ) and Social Responsiveness Scale (SRS) to account for the prevalence, severity, and nature of social problems. In a parallel study, comprehensive ASD assessment was performed in a subgroup of NF1 children with a strong suspicion of ASD (n = 31). Results indicate that NF1 children have more social problems than typical controls, more frequently reported above 8 years. The SRS shows that 63% is at risk of ASD symptoms. According to item analyses, most problems were observed on items measuring orientation in, understanding of and being tuned onto a social situation (CSBQ) and social cognition and communication (SRS). In the parallel study, 27 NF1 children were diagnosed with ASD. These children have a distinct phenotype compared to a heterogeneous ASD group, with pronounced social-communicative impairments and fewer restrictive/repetitive behaviors. This study provides a better understanding of social problems in NF1 and the phenotypical overlap with ASD symptomatology. Despite their willingness to engage with others, NF1 children with or without ASD encounter various difficulties in their social-communicative life.