Neurodevelopmental impairments in children with septo-optic dysplasia spectrum conditions: a systematic review

Abstract Background Septo-optic dysplasia (SOD) is a rare condition diagnosed in children with two or more of the following: hypopituitarism, midline brain abnormalities, and optic nerve hypoplasia. Children with SOD experience varied visual impairment and endocrine dysfunction. Autistic-like behaviours have been reported; however, their nature and prevalence remain to be fully understood. The present systematic review aimed to explore the type and prevalence of neurodevelopmental impairments in children with SOD spectrum conditions. Methods The search was conducted in PubMed, EMBASE, and PsycInfo. Hand-searching reference lists of included studies was conducted. All peer-reviewed, observational studies assessing behavioural and cognitive impairments or autism spectrum disorder (ASD) symptoms in children (< 18 years) with SOD, optic nerve hypoplasia, and SOD-plus were included. Studies were excluded if they did not report standardised measures of neurodevelopmental impairments or ASD outcomes. Results From 2132 screened articles, 20 articles reporting data from a total of 479 children were included in prevalence estimates. Of 14 studies assessing cognitive-developmental outcomes, 175 of 336 (52%) children presented with intellectual disability or developmental delay. A diagnosis of ASD or clinical level of symptoms was observed in 65 of 187 (35%) children across five studies. Only five studies assessed for dysfunction across behavioural, emotional, or social domains and reported impairments in 88 of 184 (48%) of children assessed. Limitations Importantly, high heterogeneity among the samples in relation to their neuroanatomical, endocrine, and optic nerve involvement meant that it was not possible to statistically assess the relative contribution of these confounding factors to the specific neurodevelopmental phenotype. This was further limited by the variation in study designs and behavioural assessments used across the included studies, which may have increased the risk of information bias. Conclusions This systematic review suggests that the prevalence of neurodevelopmental impairments in children within the SOD spectrum may be high. Clinicians should therefore consider including formal assessments of ASD symptoms and neurodevelopmental impairments alongside routine care. There is, additionally, a need for further research to define and validate a standardised battery of tools that accurately identify neurodevelopmental impairments in SOD spectrum conditions, and for research to identify the likely causal mechanisms

Exceptional diazoxide sensitivity in hyperinsulinaemic hypoglycaemia due to a novel HNF4A mutation

Diazoxide is the first-line treatment for patients with hyperinsulinaemic hypoglycaemia (HH). Approximately 50% of patients with HH are diazoxide resistant. However, marked diazoxide sensitivity resulting in severe hyperglycaemia is extremely uncommon and not reported previously in the context of HH due to HNF4A mutation. We report a novel observation of exceptional diazoxide sensitivity in a patient with HH due to HNF4A mutation. A female infant presented with severe persistent neonatal hypoglycaemia and was diagnosed with HH. Standard doses of diazoxide (5 mg/kg/day) resulted in marked hyperglycaemia (maximum blood glucose 21.6 mmol/L) necessitating discontinuation of diazoxide. Lower dose of diazoxide (1.5 mg/kg/day) successfully controlled HH in the proband, which was subsequently confirmed to be due to a novel HNF4A mutation. At 3 years of age, the patient maintains age appropriate fasting tolerance on low dose diazoxide (1.8 mg/kg/day) and has normal development. Diagnosis in proband’s mother and maternal aunt, both of whom carried HNF4A mutation and had been diagnosed with presumed type 1 and type 2 diabetes mellitus, respectively, was revised to maturity-onset diabetes of young (MODY). Proband’s 5-year-old maternal cousin, also carrier of HNF4A mutation, had transient neonatal hypoglycaemia. To conclude, patients with HH due to HNF4A mutation may require lower diazoxide than other group of patients with HH. Educating the families about the risk of marked hyperglycaemia with diazoxide is essential. The clinical phenotype of HNF4A mutation can be extremely variable

Central Diabetes Insipidus in Children and Adolescents:Twenty-Six Year Experience from a Single Centre

INTRODUCTION: Paediatric cohorts of central diabetes insipidus (CDI) have shown varying prevalence for different causes of CDI. The objective of this study was to determine the causes of CDI and long-term outcome in children and adolescents from a Tertiary Paediatric Endocrinology unit. METHODS: The clinic database was searched to identify patients with CDI managed between 1993 and 2019. Relevant clinical information was collected from patient records. RESULTS: A total of 138 CDI patients, median age 6 years (range <1–18) at presentation, were identified. Principal CDI aetiologies were craniopharyngioma (n = 44), acute central nervous system (CNS) insult (n = 33), germinoma (n = 15), postneurosurgery (indication other than craniopharyngioma and germinoma, n = 20), midline CNS malformation (n = 14), Langerhans cell histiocytosis (n = 5), and familial (n = 2). Idiopathic CDI in this cohort was infrequent (n = 5). Patients with CNS malformations/infections presented with CDI at a younger age compared to patients with CNS tumours (p < 0.0001). Five patients, initially presenting as idiopathic CDI, were subsequently diagnosed with germinoma after a median interval of 3.3 years. All patients with CDI related to craniopharyngioma and nearly all (87%) patients with CDI related to germinoma had concomitant GH, ACTH, and TSH deficiency. The majority of patients who manifested CDI due to acute CNS insult either deceased (30%) or had transient CDI (33.3%). CONCLUSION: Surgery for craniopharyngioma was the most common underlying aetiology of CDI with ubiquitous occurrence of panhypopituitarism in these patients. Manifestation of CDI in patients with acute CNS insult carries poor prognosis. We affirm that neuroimaging assessment in idiopathic CDI should be continued beyond 3 years from diagnosis as a significant number of patients exhibited progression of infundibular thickening 3 years post-CDI diagnosis