Missense variants in RPH3A cause defects in excitatory synaptic function and are associated with a clinically variable neurodevelopmental disorder.

PURPOSE: RPH3A encodes a protein involved in the stabilization of GluN2A subunit of N-methyl-D-aspartate (NMDA)-type glutamate receptors at the cell surface, forming a complex essential for synaptic plasticity and cognition. We investigated the effect of variants in RPH3A in patients with neurodevelopmental disorders. METHODS: By using trio-based exome sequencing, GeneMatcher, and screening of 100,000 Genomes Project data, we identified 6 heterozygous variants in RPH3A. In silico and in vitro models, including rat hippocampal neuronal cultures, have been used to characterize the effect of the variants. RESULTS: Four cases had a neurodevelopmental disorder with untreatable epileptic seizures [p.(Gln73His)dn; p.(Arg209Lys); p.(Thr450Ser)dn; p.(Gln508His)], and 2 cases [p.(Arg235Ser); p.(Asn618Ser)dn] showed high-functioning autism spectrum disorder. Using neuronal cultures, we demonstrated that p.(Thr450Ser) and p.(Asn618Ser) reduce the synaptic localization of GluN2A; p.(Thr450Ser) also increased the surface levels of GluN2A. Electrophysiological recordings showed increased GluN2A-dependent NMDA ionotropic glutamate receptor currents for both variants and alteration of postsynaptic calcium levels. Finally, expression of the Rph3AThr450Ser variant in neurons affected dendritic spine morphology. CONCLUSION: Overall, we provide evidence that missense gain-of-function variants in RPH3A increase GluN2A-containing NMDA ionotropic glutamate receptors at extrasynaptic sites, altering synaptic function and leading to a clinically variable neurodevelopmental presentation ranging from untreatable epilepsy to autism spectrum disorder.

Somatosensory cortex of macaque monkeys is designed for opposable thumb.

The evolution of opposable thumb has enabled fine grasping ability and precision grip, therefore the ability to finely manipulate the objects and refined tool use. Since tactile inputs to an opposable thumb are often spatially and temporally out of sync with inputs from the fingers, we hypothesized that inputs from the opposable thumb would be processed in an independent module in the primary somatosensory cortex (area 3b). Here we show that in area 3b of macaque monkeys, most neurons in the thumb representation do not respond to tactile stimulation of other digits and receive few intrinsic cortical inputs from other digits. However, neurons in the representations of other 4 digits respond to touch on any of the 4 digits and interconnect significantly more. The thumb inputs are thus processed in an independent module, whereas there is a significantly more interdigital information exchange between the other digits. This cortical organization reflects behavioral use of a hand with an opposable thumb.

Process evaluation of paediatric fellowship training programs at a University Hospital in Pakistan.

BACKGROUND: Fellowship programs offer training in a subspecialty focusing on distinct and advanced clinical/academic skills. This advanced postgraduate training allows physicians, who desire a more specialized practice, to further develop clinical, academic, research, and leadership/administrative skills. The Aga Khan University (AKU) is one of the few institutes offering paediatric sub-specialty training in Pakistan. We aimed to evaluate the current Paediatric fellowship programs at AKU. METHODS: Process evaluation of six paediatric fellowship programs (cardiology, neurology, endocrinology, critical care medicine, neonatology, and infectious disease) was conducted from September 2020 to April 2021 by senior clinicians and medical educationists. Evidence was collected through document review (using existing postgraduate medical education program information form), observation of teaching and learning support, and focused group discussions/interviews with program faculty and fellows were conducted. A review of the evaluation report was done as part of this study. This study received an exemption from the ethical review committee. The quantitative data were analyzed using SPSS (22.0) while the reports of discussion with fellows and friends underwent content analysis. RESULTS: All fellowship programs met the criteria for having a robust competency-based fellowship curriculum as per the institutional and national guidelines. Formative assessment in the form of continuous evaluation was found to be integrated into all the fellowship programs, however, most of the programs were found to lack a summative assessment plan. Fellows in training and program faculty were satisfied with the opportunities for mentorship, teaching, and learning. Thematic analysis of the discussion reports with faculty and fellows revealed three key themes including, program aspects translating into strengthening the training, gaps in the training program in delivering the expectations, and making ways to reach par excellence. CONCLUSIONS: The process evaluation of paediatric fellowship programs provided an opportunity to holistically review the current strengths and quality of the training in individual programs along with the unmet needs of the trainees. This will help the program stakeholders to prioritize, align and allocate the resources to further enhance the quality of training and outcome of individual fellowship programs to ensure wider impacts at a regional, national, and international health system level.

Mutation Of TBC1 Domain Containing Kinase (TBCK) With Associated Intellectual Disability And Hypotonia.

Infantile Hypotonia with Psychomotor Retardation and Characteristic Facies-3 (IHPRF-3) Syndrome is a rare pathology occurring due to mutations in the TBC1 domain containing kinase (TBCK). This is a neurodevelopmental disorder presenting with a neurological and dysmorphic feature including intellectual disability, limb and craniofacial abnormalities. We present a case of TBCK mutation of the variant (p.Gln164*), present on Exon 6; this sequence change creates a premature translational stop signal (p.Gln164*) in TBCK, creating a disrupted protein leading to a loss of function. This variant has not yet been reported in genetic databases. We need to establish a better understanding of this disorder by reporting these novel genetic mutations so that these complex patients can be successfully managed by multidisciplinary teams.

Potassium Voltage-Gated Channel Subfamily H Member 1 (KCNH1) Missense Mutation Causing Epileptic Encephalopathy And Autistic Behaviour.

The phenotypically similar genetic diseases Zimmermann Laband syndrome (ZLS) and Temple-Baraitser syndrome (TMBTS) cause neurodevelopmental problems. Mutations in the gene coding for potassium voltage-gated channel, primarily KCNH1, cause these symptoms. An uncommon mutation in KCNH1 (p.Arg357Trp) present on Exon 7, reported to replace arginine with tryptophan at codon 357 of the KCNH1 protein c.1069C>T, caused pharma coresistantseizures and autistic behaviour in a 2.7-year-old boy. This mutation causes problems with protein modelling and has yet to be documented in any genetic databases around the world. This mutation was overlapped with GPHN gene, c.828+1G>A, in our patient, causing GPHN related spectrum disorder (autosomal dominant) along with molybdenum cofactor deficiency (autosomal recessive) leading to a neuropsychiatric presentation including autistic behaviour, making diagnosis and management even more complicated.

Early Infantile Epileptic Encephalopathy In Asparagine-Linked Glycosylation Thirteen (ALG13) Gene Defect And Dramatic Response With Ketogenic Diet.

Asparagine-linked glycosylation thirteen (ALG13) gene-related congenital disorders of glycosylation (CDGs) include early onset epileptic encephalopathy (EIEE), developmental delays (DD) with intellectual disability (ID), speech and visual abnormalities, and haematologic and endocrine dysfunctions. Worldwide there is a scarcity of available data on this. To add to this scarce data, we report the case of a young girl with this rare genetic mutation who showed remarkable improvement in her seizures by addition of ketogenic diet (KD) to her management regimen. With an already high rate of consanguineous marriages, metabolic and genetic errors are widely prevalent; hence, to bridge the huge gap in the understanding of such diseases, further research and trials are needed to be carried out to improve identification of the disease along with outcomes.

Potassium Channel Subfamily T Member 1(KCNT1) Pathological Variant Causing Epilepsy Of Infancy With Migrating Focal Seizures: A Case Report.

Pathological mutation of potassium channel subfamily T member 1 (KCNT1) gene causes an autosomal dominant disorder characterised by secondarily generalised seizures/migratory focal seizure, cyanosis, and dysmorphic features. We report the case of a five-month old male with pathological KCNT1 variant who presented with focal clonic seizures, Mongol spots, and grade two systolic murmur at the left lower sternal border and loud P2. The seizures were refractory to most anti-epileptic drugs but showed some response to Valproic acid. This case demonstrated that EIMFS is a grave infantile epileptic encephalopathy which is refractory to anti epileptic drugs and can present with a wide spectrum of neurogenic and cardiogenic symptoms.

Urinary metabolomics using gas chromatography-mass spectrometry: potential biomarkers for autism spectrum disorder.

BACKGROUND: Diagnosis of autism spectrum disorder (ASD) is generally made phenotypically and the hunt for ASD-biomarkers continues. The purpose of this study was to compare urine organic acids profiles of ASD versus typically developing (TD) children to identify potential biomarkers for diagnosis and exploration of ASD etiology. METHODS: This case control study was performed in the Department of Pathology and Laboratory Medicine in collaboration with the Department of Pediatrics and Child Health, Aga Khan University, Pakistan. Midstream urine was collected in the first half of the day time before noon from the children with ASD diagnosed by a pediatric neurologist based on DSM-5 criteria and TD healthy controls from August 2019 to June 2021. The urine organic acids were analyzed by Gas Chromatography-Mass Spectrometry. To identify potential biomarkers for ASD canonical linear discriminant analysis was carried out for the organic acids, quantified in comparison to an internal standard. RESULTS: A total of 85 subjects were enrolled in the current study. The mean age of the ASD (n = 65) and TD groups (n = 20) was 4.5 ± 2.3 and 6.4 ± 2.2 years respectively with 72.3% males in the ASD group and 50% males in the TD group. Parental consanguinity was 47.7 and 30% in ASD and TD groups, respectively. The common clinical signs noted in children with ASD were developmental delay (70.8%), delayed language skills (66.2%), and inability to articulate sentences (56.9%). Discriminant analysis showed that 3-hydroxyisovalericc, homovanillic acid, adipic acid, suberic acid, and indole acetic were significantly different between ASD and TD groups. The biochemical classification results reveal that 88.2% of cases were classified correctly into ASD& TD groups based on the urine organic acid profiles. CONCLUSION: 3-hydroxy isovaleric acid, homovanillic acid, adipic acid, suberic acid, and indole acetic were good discriminators between the two groups. The discovered potential biomarkers could be valuable for future research in children with ASD.

The pro-inflammatory effects of combined exposure to diesel exhaust particles and mineral particles in human bronchial epithelial cells.

BACKGROUND: People are exposed to ambient particulate matter (PM) from multiple sources simultaneously in both environmental and occupational settings. However, combinatory effects of particles from different sources have received little attention in experimental studies. In the present study, the pro-inflammatory effects of combined exposure to diesel exhaust particles (DEP) and mineral particles, two common PM constituents, were explored in human lung epithelial cells. METHODS: Particle-induced secretion of pro-inflammatory cytokines (CXCL8 and IL-1ß) and changes in expression of genes related to inflammation (CXCL8, IL-1α, IL-1ß and COX-2), redox responses (HO-1) and xenobiotic metabolism (CYP1A1 and CYP1B1) were assessed in human bronchial epithelial cells (HBEC3-KT) after combined exposure to different samples of DEP and mineral particles. Combined exposure was also conducted using lipophilic organic extracts of DEP to assess the contribution of soluble organic chemicals. Moreover, the role of the aryl hydrocarbon receptor (AhR) pathway was assessed using an AhR-specific inhibitor (CH223191). RESULTS: Combined exposure to DEP and mineral particles induced increases in pro-inflammatory cytokines and expression of genes related to inflammation and redox responses in HBEC3-KT cells that were greater than either particle sample alone. Moreover, robust increases in the expression of CYP1A1 and CYP1B1 were observed. The effects were most pronounced after combined exposure to α-quartz and DEP from an older fossil diesel, but enhanced responses were also observed using DEP generated from a modern biodiesel blend and several stone particle samples of mixed mineral composition. Moreover, the effect of combined exposure on cytokine secretion could also be induced by lipophilic organic extracts of DEP. Pre-incubation with an AhR-specific inhibitor reduced the particle-induced cytokine responses, suggesting that the effects were at least partially dependent on AhR. CONCLUSIONS: Exposure to DEP and mineral particles in combination induces enhanced pro-inflammatory responses in human bronchial epithelial cells compared with exposure to the individual particle samples. The effects are partly mediated through an AhR-dependent pathway and lipophilic organic chemicals in DEP appear to play a central role. These possible combinatory effects between different sources and components of PM warrant further attention and should also be considered when assessing measures to reduce PM-induced health effects.

Hypermanganesaemia with dystonia polycythemia and cirrhosis.

Hypermanganesaemia with dystonia, polycythemia, and cirrhosis (HMDPC) is a rare genetic and autosomal recessive disorder that occurs due to mutation of the SLC3A10 gene, which encodes the manganese (Mn) transporter in the body; as a result, Mn accumulates in the brain, liver and muscles. This accumulation leads to symptoms of generalized dystonia, polycythemia, and hypermanganesaemia. In this report, we present the case of a 2½-year-old baby girl (patient) with complaints of lower limb weakness and increased difficulty in walking for six months. Her laboratory test results showed deranged values with increased Mn levels in the body. The patient was put on six cycles of EDTA therapy, which showed an improvement in her condition. This case report is presented to create awareness about a rare genetic disorder with an effective treatment in some cases. Thus, more work and research is required to understand and develop better treatment options for this disease.

Altered Expression of Reorganized Inputs as They Ascend From the Cuneate Nucleus to Cortical Area 3b in Monkeys With Long-Term Spinal Cord Injuries.

Chronic deafferentations in adult mammals result in reorganization of the brain. Lesions of the dorsal columns of the spinal cord at cervical levels in monkeys result in expansion of the intact chin inputs into the deafferented hand representation in area 3b, second somatosensory (S2) and parietal ventral (PV) areas of the somatosensory cortex, ventroposterior lateral nucleus (VPL) of the thalamus, and cuneate nucleus of the brainstem. Here, we describe the extent and nature of reorganization of the cuneate and gracile nuclei of adult macaque monkeys with chronic unilateral lesions of the dorsal columns, and compare it with the reorganization of area 3b in the same monkeys. In both, area 3b and the cuneate nucleus chin inputs expand to reactivate the deafferented neurons. However, unlike area 3b, neurons in the cuneate nucleus also acquire receptive fields on the shoulder, neck, and occiput. A comparison with the previously published results shows that reorganization in the cuneate nucleus is similar to that in VPL. Thus, the emergent topography following deafferentations by spinal cord injuries undergoes transformation as the reorganized inputs ascend from subcortical nuclei to area 3b. The results help us understand mechanisms of the brain plasticity following spinal cord injuries.

Menkes disease: A rare disorder.

Menkes disease (MD) (OMIM: 309400) is also known as kinky hair disease, trichopoliodystrophy, and steely hair. A 7-months-old, male infant presented to our outpatient department in June 2016 with history of developmental delay and seizures. Seizures started at 3 months of age and worsened progressively to clusters of extensor spasms. Physical examination showed sparse and kinky hair. Neurological examination revealed a central hypotonia with marked decrease in muscle power with normal deep tendon reflexes. The serum ceruloplasmin level and serum copper level were decreased. Ultrasound KUB showed Hutch diverticulum along left ureteric orifice. Magnetic resonance imaging (MRI) carried out at five months of age showed frontal cortical atrophy. His EEG was consistent with hypsarrythmia pattern. Patients with classic MD usually exhibit a severe neurodegenerative course, with poor long term outcome and death before the third year of life.

Hemimegalencephaly with intractable epilepsy: A case report.

Isolated Hemimegalencephaly (iHME) is a rare form of congenital malformation of cortical development.It is characterized by enlargement of all or part of one cerebral hemisphere. It typically presents with intractable seizures, mental retardation, developmental delay, contralateral hemiparesis and hemianopia. The patient was a five and half month's old baby girl who presented first with focal seizures at 10th day of life. No other physical or behavioral abnormality was noted. However, Initial EEG showed excessive sharp EEG transients more over the right hemisphere, repeated EEG showed spikes, polyspikes, sharps and slow wave discharges predominately over right hemisphere. MRI brain showed asymmetric enlargement of the right cerebral hemisphere, suggestive of hemimegalencephaly. Initial treatment with anti-epileptics was successful in controlling the seizures but later on the seizures became intractable even on polytherapy. Identification of this and similar cases of iHME can help us better understand this disorder and its associated symptoms and eventually help us develop better treatment options for it.

Intracortical and Thalamocortical Connections of the Hand and Face Representations in Somatosensory Area 3b of Macaque Monkeys and Effects of Chronic Spinal Cord Injuries.

Brains of adult monkeys with chronic lesions of dorsal columns of spinal cord at cervical levels undergo large-scale reorganization. Reorganization results in expansion of intact chin inputs, which reactivate neurons in the deafferented hand representation in the primary somatosensory cortex (area 3b), ventroposterior nucleus of the thalamus and cuneate nucleus of the brainstem. A likely contributing mechanism for this large-scale plasticity is sprouting of axons across the hand-face border. Here we determined whether such sprouting takes place in area 3b. We first determined the extent of intrinsic corticocortical connectivity between the hand and the face representations in normal area 3b. Small amounts of neuroanatomical tracers were injected in these representations close to the electrophysiologically determined hand-face border. Locations of the labeled neurons were mapped with respect to the detailed electrophysiological somatotopic maps and histologically determined hand-face border revealed in sections of the flattened cortex stained for myelin. Results show that intracortical projections across the hand-face border are few. In monkeys with chronic unilateral lesions of the dorsal columns and expanded chin representation, connections across the hand-face border were not different compared with normal monkeys. Thalamocortical connections from the hand and face representations in the ventroposterior nucleus to area 3b also remained unaltered after injury. The results show that sprouting of intrinsic connections in area 3b or the thalamocortical inputs does not contribute to large-scale cortical plasticity. Significance statement: Long-term injuries to dorsal spinal cord in adult primates result in large-scale somatotopic reorganization due to which chin inputs expand into the deafferented hand region. Reorganization takes place in multiple cortical areas, and thalamic and medullary nuclei. To what extent this brain reorganization due to dorsal column injuries is related to axonal sprouting is not known. Here we show that reorganization of primary somatosensory area 3b is not accompanied with either an increase in intrinsic cortical connections between the hand and face representations, or any change in thalamocortical inputs to these areas. Axonal sprouting that causes reorganization likely takes place at subthalamic levels.

Hereditary Sensory Autonomic Neuropathy II, a rare disease in a large Pakistani family.

Hereditary Sensory Autonomic Neuropathy II (HSAN II) is a rare genetic disorder, characterized by severe loss of pain, temperature and touch sensation. Injuries in these patients can progress to necrosis and shedding of digits and limbs. Here we report two cases of HSAN II belonging to a Pakistani family. Individual 1, a forty five year old man, had complete loss of pain sensation since birth. Self-mutilation and complication of injuries resulted in the shedding of all the digits and right foot and surgical amputation of left leg. Individual 2, a five year old girl,had delay in healing of wounds and self-mutilation. Examination showed a complete lack of pain sensation throughout her body and hyporeflexia. As the genetic cause of HSAN II is unknown, identification of more patients will allow further research on this disease and possibly develop a cure.

The upsurge of SSPE--a reflection of national measles immunization status in Pakistan.

Subacute sclerosing panencephalitis (SSPE) is a rare disorder in the developed world. However, an upsurge has been seen lately in our part of the world owing to inadequate measles immunization coverage. At the midst of our struggle against polio, we are struggling with the war against other vaccine-preventable childhood illnesses like measles. The increasing numbers of SSPE that we reported over the past half decade suggest an underlying periodic measles epidemic in Pakistan. In addition, children are now presenting with SSPE in early childhood, warranting a relook, reinforcement and strengthening of primary immunization and mandatory two-dose measles vaccination for all children nationwide. Previously undertaken Measles Supplementary Immunization Activity were a failure in terms of providing the expected cover against measles in young children. Intensive surveillance and establishment of SSPE registers at the district level is essential for eradication of this easily preventable disorder. Unless timely efforts are made to achieve global immunization, SSPE is bound to add to the national disability burden.

Experiences of identifying pre-school children with disabilities in resource limited settings - an account from Malawi, Pakistan and Uganda.

Although access to effective medical care for acutely sick children has improved globally, the number of children surviving but who may not be thriving due to disability, is increasing. This study aimed to understand the views of health professionals, educators and caregivers of pre-school children with disabilities in Malawi, Pakistan and Uganda regarding early identification, referral and support. Using applied thematic analysis, we identified themes relating to; limited 'demand' by caregivers for services; different local beliefs and community perceptions regarding the causes of childhood disability. Themes relating to 'supply' of services included inability to respond to community needs, and inadequate training among professionals for identification and referral. Stepwise, approaches provided to the families, community health worker and higher-level services could include training for community and primary care health workers on basic identification techniques and enhanced awareness for families and communities on the importance of early identification of children with disabilities.

Lack of collaboration between the community and health services may lead to entrenched pessimistic views of what can be done to support children with disabilities - generating a greater mistrust and low parental take-up of vital health services.If parents do not receive help at the community and clinic level, then, there is a need to move away from trying to provide a 'specific diagnosis' to working more on a level of assessing the child's functioning in terms of what their limitations are and how they can be addressed.Any identification and referral programme needs to consider the varying local beliefs, the stigma of having a child with a disability and feelings of blame, right from the start.A stepwise, incremental approaches, ranging from the provision of basic information, such as using brief materials highlighting 'red flag' milestones and conditions which are linked to guidance for support to families, community health workers, as well as higher levels of medical services, are likely to work best.

Structural Changes in the Brain on Magnetic Resonance Imaging in Malnourished Children: A Scoping Review of the Literature.

BACKGROUND: This review was conducted to summarize the current evidence on the structural findings seen in brain magnetic resonance imaging (MRI) in malnourished children and the effect of optimized nutritional supplementation on brain development as studied through MRI. METHODS: A systematic search was carried out in PubMed, Embase, The Cochrane Library, Web of Science (Clarivate Analytics), WHO ICTRP Clinical Trials in Children, and ClinicalTrials.gov using a predefined search criterion for relevant literature from inception to January 2022. The primary outcome of the study was structural changes observed in the brain on MRI. RESULTS: The most common abnormal findings on MRI in malnourished infants were cerebral atrophy and dilated ventricles. Furthermore, a higher proportion of breast milk, calorie, and lipid intake in the diet was significantly associated with increased brain volumes; this also increased the likelihood of normal MRI scores at term. When followed till adolescence, it was observed that these infants had increased neonatal weight gain and a higher intelligence quotient when compared with the group. CONCLUSIONS: In conclusion, most children with moderate/severe malnutrition had abnormal MRI findings, mostly cerebral atrophy with or without ventricular dilatation. Since none of the studies measured the degree of atrophy or ventricular dilatation, it was not possible to assess the effect of the severity of malnutrition on brain atrophy. A universal measurement or scoring system for assessing the degree of brain atrophy is needed to help correlate the severity of malnutrition with the degree of brain atrophy and monitor the effects of nutritional rehabilitation over time.

Spectrum of Common Pediatric Neurological Disorders: A Cross-Sectional Study From Three Tertiary Care Centres Across Pakistan.

BACKGROUND: There is dearth of information on the spectrum of neurological disorders among children less than 18 years of age. The aim of this study is to identify the commonly presenting neurological disorders among children aged ≤ 18 years in Pakistan. METHODS: We conducted a cross-sectional study at three tertiary care hospitals in Pakistan. RESULTS: A total of 17,176 children were included in our study; 61.8% were boys and 38.2% females. The most commonly presenting neurological disorder was epilepsy (36%), followed by behavior disorders (16%) and cerebral palsy (10.5%). There was significant difference between children less than 5 years and greater than 5 years age groups, with less than 5 years age group showing higher prevalence for behavioral disorders (P < 0.001), cerebral palsy (P < 0.001), infections (P = 0.014), sequalae (P < 0.001), and developmental disorders (P < 0.001). Gender-wise distribution showed epilepsy to be the most common neurological disorder among both genders, with a significant difference being reported between gender and epilepsy (P = 0.009), headache disorders (P < 0.001), neuroinflammatory disorders (P = 0.025), neurocutaneous syndromes (P < 0.001), behavioral diseases (P < 0.001), cerebral palsy (P = 0.009), and movement disorders (P < 0.001). CONCLUSIONS: The result of this analysis helps to assess the commonly presenting neurological disorders in children. This study will help health care workers in resource-poor settings within Pakistan to be mindful of the common neurological disorders while diagnosing a child with neurological symptoms in an outpatient setting. Health care providers need to be trained to identify and treat these common conditions; however, there is still a dire need for more trained neurologists across the country.