A novel CHD3 variant in a patient with central precocious puberty: Expanded phenotype of Snijders Blok-Campeau syndrome?

Snijders Blok-Campeau syndrome is an autosomal dominant genetic disorder first described in 2018, mostly associated with de novo variants in the CHD3 gene that affects chromatin remodeling. This syndrome is characterized by developmental delay, speech delay, and intellectual disability, but only about 60 affected individuals have been reported to date. We report a de novo likely pathogenic CHD3 variant (c.5609G > A; p. (Arg1870Gln)) in a young female presenting with features of Snijders Blok-Campeau syndrome including speech delay, autism spectrum disorder, learning difficulties, characteristic facial dysmorphisms, and a feature not previously described in this syndrome, idiopathic central precocious puberty. Her puberty was controlled with monthly injections of a GnRH analogue. Targeted exome sequencing was negative for genes known to be responsible for central precocious puberty. Our case raises the possibility that variants in CHD3 gene may also result in central precocious puberty. Strengthening this association could expand the phenotypic spectrum of the Snijders Blok-Campeau syndrome and should be included in multigene panels for precocious puberty.

Canadian clinical capacity for fetal alcohol spectrum disorder assessment, diagnosis, disclosure and support to children and adolescents: a cross-sectional study.

OBJECTIVE: Canadian fetal alcohol spectrum disorder (FASD) guidelines encourage an age-specific interdisciplinary diagnostic approach. However, there is currently no standard-of-care regarding FASD diagnosis disclosure and few studies document Canadian FASD clinical capacity. Our objectives were to describe clinical capacity (defined as skills and resources) for FASD assessment, diagnosis, disclosure and support in Canada. DESIGN, SETTING AND PARTICIPANTS: Data were drawn from the CanDiD study, a cross-sectional investigation of Canadian FASD clinical capacity. Forty-one clinics participated in the study. Data were collected in 2021 on the number and types of health professionals included in the assessment and diagnostic teams, the presence (or absence) of a minor patient when the FASD diagnosis is disclosed to parents/guardians, who is responsible for the diagnosis disclosure, the use of explanatory tools, and the types of support/counselling services available. The proportion of clinics that follow the Canadian interdisciplinary diagnostic guidelines by age group is described among participating clinics. RESULTS: Overall, 21, 13 and 7 specialised FASD clinics were in Western/Northern, Central and Atlantic Canada, respectively. The number of referrals per year surpassed the number of diagnostic assessments completed in all regions. Approximately, 60% of clinics who diagnosed FASD in infants and preschool children (n=4/7 and 15/25, respectively) followed the interdisciplinary guidelines compared with 80% (n=32/40) in clinics who diagnosed school-aged children/adolescents. Diagnostic reporting practices were heterogeneous, but most used an explanatory tool with children/adolescents (67%), offered support/counselling (90-95%) and used case-by-case approach (80%) when deciding who would disclose the diagnosis to the child/adolescent and when. CONCLUSIONS: Limited diagnostic capacity and lack of FASD resources across Canada highlights a critical need for continued FASD support. This study identifies gaps in assessment, diagnosis and reporting practices for FASD in children/adolescents across Canada.