Angelman syndrome presenting with a rare seizure type in a patient with 15q11.2 deletion: a case report

A multidisciplinary approach and consensus statement to establish standards of care for Angelman syndrome

BACKGROUND

Angelman syndrome (AS) is a rare neurogenetic disorder present in approximately 1/12,000 individuals and characterized by developmental delay, cognitive impairment, motor dysfunction, seizures, gastrointestinal concerns, and abnormal electroencephalographic background. AS is caused by absent expression of the paternally imprinted gene UBE3A in the central nervous system. Disparities in the management of AS are a major problem in preparing for precision therapies and occur even in patients with access to experts and recognized clinics. AS patients receive care based on collective provider experience due to limited evidence-based literature. We present a consensus statement and comprehensive literature review that proposes a standard of care practices for the management of AS at a critical time when therapeutics to alter the natural history of the disease are on the horizon.

METHODS

We compiled the key recognized clinical features of AS based on consensus from a team of specialists managing patients with AS. Working groups were established to address each focus area with committees comprised of providers who manage >5 individuals. Committees developed management guidelines for their area of expertise. These were compiled into a final document to provide a framework for standardizing management. Evidence from the medical literature was also comprehensively reviewed.

RESULTS

Areas covered by working groups in the consensus document include genetics, developmental medicine, psychology, general health concerns, neurology (including movement disorders), sleep, psychiatry, orthopedics, ophthalmology, communication, early intervention and therapies, and caregiver health. Working groups created frameworks, including flowcharts and tables, to help with quick access for providers. Data from the literature were incorporated to ensure providers had review of experiential versus evidence-based care guidelines.

CONCLUSION

Standards of care in the management of AS are keys to ensure optimal care at a critical time when new disease-modifying therapies are emerging. This document is a framework for providers of all familiarity levels.

Low-Density Neuronal Cultures from Human Induced Pluripotent Stem Cells

Induced pluripotent stem cell (iPSC)-based technologies offer an unprecedented possibility to investigate defects occurring during neuronal differentiation in neuropsychiatric and neurodevelopmental disorders, but the density and intricacy of intercellular connections in neuronal cultures challenge currently available analytic methods. Low-density neuronal cultures facilitate the morphometric and functional analysis of neurons. We describe a differentiation protocol to generate low-density neuronal cultures (∼2,500 neurons/cm²) from human iPSC-derived neural stem cells/early neural progenitor cells. We generated low-density cultures using cells from 3 individuals. We also evaluated the morphometric features of neurons derived from 2 of these individuals, one harboring a microdeletion on chromosome 15q11.2 and the other without the microdeletion. An approximately 7.5-fold increase in the density of dendritic filopodia was observed in the neurons with the microdeletion, consistent with previous reports. Low-density neuronal cultures enable facile and unbiased comparisons of iPSC-derived neurons from different individuals or clones.

An unusual case of adolescent type 2 diabetes mellitus: Prader-Willi syndrome

Prader-Willi syndrome (PWS) is a complex genetic disorder, characterized by neonatal hypotonia, developmental delay, short stature, childhood obesity, hypogonadism, and characteristic facial features. Here we report a 21-year-old male who presented with uncontrolled glycemic status. He was diagnosed to have diabetes mellitus at the age of 15 with osmotic symptoms - polyuria, polydipsia, and polyphagia. In the early period, after diagnosis, his blood sugars were reasonably controlled with oral hypoglycemic agents. However, a year back, he was switched onto insulin therapy due to secondary OHA failure. On examination, his body mass index was 36 kg/m(2). He had bilateral gynecomastia, decreased biparietal diameter, almond shaped eyes with esotropia. He had hypogonadism and also had mild cognitive impairment. He did not have any proximal myopathy or other focal neurological deficits. Hormonal evaluation showed low testosterone and inappropriately normal fluorescence in situ hybridization suggestive of central hypogonadism. With fetal and neonatal hypotonia, delayed developmental milestones, hypogonadism, and early onset diabetes, he fulfilled the clinical criteria for the diagnosis of PWS. Multidisciplinary approach of clinicians together with family and social support are essential to bring out the optimal outcome for such syndromic cases.