The Spectrum of Inherited Gray Matter Degenerative Brain Disorders (DBD) in Children: A Single-Center Study.

Objectives: To study the clinical spectrum of inherited gray matter degenerative brain disorders (DBD) in children. Methods: This cross-sectional study evaluated children up to 12 y of age, diagnosed with an inherited gray matter DBD in a tertiary care pediatric hospital between July 2019 and December 2020. Results: A total of 314 children with progressive neuroregression were screened. Of these, 117 children with inherited gray matter DBD were included in the study. The clinic-based prevalence of DBD was 8.2%, and inherited gray matter DBD was 3.1%. The proportion of the inherited gray matter DBD was 37.3% among the overall DBD cases. Children were categorized into three groups based on the age at onset of disease: below 2 years (N = 57, 48.7%), between 2 and 5 years (N = 32, 27.3%), and between 6 and 12 years (N = 28, 23.9%). Based on the predominant cerebral structure involved, gray matter DBD were classified as cerebral gray matter disorders (53%), basal ganglia disorders (34.1%), and cerebellar disorders (12.8%). Overall, the most common disorders were Wilson disease (18%), neuronal ceroid lipofuscinosis (NCL) (17%), and neurodegeneration with brain iron accumulation (NBIA) (16%). The most common gray matter DBD in children <2 years of age were NBIA (n = 11), Rett syndrome (n = 11), and gangliosidoses (n = 10). NCL (n = 14) and ataxia telangiectasia (n = 6) were most common in the age group of 2-5 years. Wilson disease (n = 19) was the most common disorder in the age group of 6-12 years followed by NCL (n = 4) and NBIA (n = 3). Conclusion: Our study highlights the burden and spectrum of gray matter DBD in children. The clinic-based prevalence of DBD was 8.2%, and of inherited gray matter DBD was 3.1%. The proportion of inherited gray matter DBD was 37.3% among the overall DBD cases. Wilson disease, NCL, and NBIA are the most common gray matter DBD in children. Timely diagnosis is important for the prevention of recurrence in subsequent pregnancies.

The Challenge of Severe Acute Malnutrition in Inborn Errors of Metabolism: Does Medical Food Alone Suffice?

Glutaric aciduria type 1 (GA-1) is a treatable inborn error of metabolism caused by glutaryl-CoA dehydrogenase deficiency. This enzyme deficiency leads to accumulation of glutaric acid, 3-hydroxy glutaric acid, and glutaconic acid which are potentially neurotoxic. Patients with GA-1 have characteristic clinical and neuroimaging features that help us to clinch the diagnosis. Early diagnosis by newborn screening helps us to prevent the motor problems such as dystonia and spasticity. Treatment includes low-protein diet along with carnitine supplementation which may lead to deficiency of essential amino acids and hence malnutrition. Managing malnutrition in a child with inborn errors of metabolism (IEM) is challenging. Here, we describe a patient, a case of GA-1 on medical food, presenting with severe acute malnutrition, who improved with a combination of medical and home-made foods along with lysine-free, tryptophan-reduced amino acid supplements.

Peripheral Neuropathy in Children With Chronic Kidney Disease: Are We Looking Enough?

Background: Peripheral neuropathy in chronic kidney disease (CKD) is the most common neurological complication. We aimed to look at the prevalence and patterns of neuropathy in children with CKD. Methods: This cross-sectional study was conducted over 1 year in children with CKD, stage III and above. Nerve conduction studies (NCS) were performed as per standard protocols using surface electrodes on the muscles and by supramaximal stimulation of the corresponding nerves. Presence of electrophysiological abnormalities in the absence of clinical symptoms or signs was considered as subclinical neuropathy. Results: Nearly 45 children were evaluated. The majority were males (n = 39, 86.7%). The mean age was 7.9 ± 3 years (range 2-14). The mean estimated glomerular filtration rate (GFR) at enrolment was 23.3 ± 14.6 mL/min/1.73 m2 (range 5-67). The majority of children were in stage III (n = 19, 42%), followed by stages V (n = 15, 33%) and IV (n = 11, 25%). There was no evidence of clinical neuropathy; 13 children (29%) showed subclinical neuropathy. All the nerves had an axonal pattern of involvement. Motor polyneuropathy was most common type of peripheral neuropathy. The commonest nerves involved were tibial and common peroneal nerves. There were no biochemical or clinical predictors of neuropathy in our cohort. Conclusion: The prevalence of subclinical neuropathy is high in children with CKD, stage III and above. Axonal motor polyneuropathy is the predominant pattern. Electrophysiological assessment of nerve function should be routinely done in children with advanced stages of CKD to prevent chronic complications.

Deflazacort dose optimization and safety evaluation in Duchenne muscular dystrophy (DOSE): A randomized, double-blind non-inferiority trial.

BACKGROUND: US food and drug administration has recently approved deflazacort for Duchenne muscular dystrophy (DMD) and recommended the dosage of 0.9 mg/kg/d for patients aged ≥5years. However, data assessing the minimal efficacious dose and need of dose-titration based on age or disease severity is limited. OBJECTIVE: To determine whether deflazacort 0.45 mg/kg/d (proposed lower dosage) is non-inferior to 0.9 mg/kg/d among newly diagnosed patients with DMD. METHOD: A double-blinded, non-inferiority, randomized trial, conducted between December 2018 and July 2020. Newly diagnosed patient aged 5-15 years with genetic or muscle biopsy confirmed DMD and baseline 6-min walk distance (6MWD) > 150 m were screened. Patients were randomly assigned (1:1), stratified to prespecified subgroups by age (≤7years and >7years), and baseline 6MWD (≤350 m and >350 m), to receive either 0.45 mg/kg/d or 0.9 mg/kg/d regimens. The primary endpoint was the change in 6MWD, from baseline to week-24 of intervention. The trial was powered with a predefined, non-inferiority margin of 30 m. The analyses were by modified intention-to-treat (mITT). RESULT: A total of 97 patients were enrolled, 40 receiving 0.45 mg/kg/d and 45 receiving 0.9 mg/kg/d deflazacort comprised of mITT population. For primary endpoint analysis the mean (SD) change in 6MWD from baseline to week-24 was 9.7 m (41.5) in deflazacort 0.45 mg/kg/d, and 34.7 m (43.5) for 0.9 mg/kg/d. The mean difference in change in 6MWD across the group was 24.8 m (95% CI 6.7 to 43, p value 0.008). The mean difference in change in 6MWD in the subgroups of boys ≤7 years of age was 21.8 m (95% CI -0.82, 44.5, p = 0.059), with baseline 6MWD of >350 m was 19.9 m (95% CI -2.4, 42.4; p = 0.08). The incidence of combined moderate to severe treatment-related adverse events was significant in the 0.9 mg/kg/d group by week 24 (odds ratio 0.36 [95% CI, 0.14 to 0.89], p = 0.03). DISCUSSION: The efficacy of proposed low dose deflazacort in comparison to the standard dose did not meet the prespecified criteria for non-inferiority. The low dose deflazacort was non-inferior in subgroup of patients with age ≤7 years and baseline 6MWD of >350 m. TRIAL REGISTRATION: Clinical Trial Registry-India Identifier: CTRI/2019/02/017388.

Hereditary Sensory and Autonomic Neuropathy: A Case Series of Six Children.

Objectives: Hereditary sensory and autonomic neuropathy (HSAN) is a group of rare disorders affecting the sensory and autonomic neurons. Herein, we describe the clinical and genetic profile of six children with HSAN. Methods: Hospital records of six children diagnosed with HSAN over 7 years (2011-2018) were retrieved. Clinical features, electrophysiological studies, and genetic reports were collected from the case files. Results: The presenting clinical features in these six cases were developmental delay, recurrent febrile episodes, rhinitis, recurrent nonhealing ulcers, burns, self-mutilations, chronic osteomyelitis, and corneal ulcers. Electrophysiology studies showed predominant sensory axonal neuropathy. Autonomic features noted were recurrent fever, constipation, abdominal distension, hypertension, and vasomotor rhinitis. Genetic testing was done with next-generation sequencing in all six children. Causative genetic variants were identified in the NTRK1, PRDM12, DST gene, and a novel compound heterozygous variant in the FLVCR1 gene. The diagnosis of HSAN was delayed in most of our children due to variable presentation and lack of awareness among the treating paediatricians. Conclusions: Although the clinical presentation of HASN is highly variable, it is dominated by pain and temperature insensitivity and self-mutilation. Our report of six children with HSAN expands the existing knowledge on phenotype and genotype spectrum of HSAN.

Comparison of Five Different Electrophysiological Criteria for Childhood Guillain Barre Syndrome.

BACKGROUND: Internationally approved electrodiagnostic criteria for Guillain Barre syndrome lack in children. We intended to compare the diagnostic accuracy of the currently available five electrophysiological criteria for childhood Guillain Barre Syndrome (GBS) at the time of sentinel assessment. METHODOLOGY: In this single-center study, data of children diagnosed with GBS between January 2013 to December 2017 were retrieved. Patient charts were reviewed for clinical features, electrophysiological recordings. The electrodiagnostic results (4 motor nerves and two sensory nerves in upper limbs and lower limbs) were reanalyzed and were classified based on Dutch group; Ho; Hadden; Hughes and Rajabally criteria for GBS. RESULTS: During this study period, of the 205 children with clinical features of GBS, 15 children had incomplete electrophysiological data, and four children were excluded due to missing data. The mean age of onset of the 186 children enrolled was 77 months; the median duration from symptom onset to electrodiagnostic evaluation was seven days; pure motor and motor-sensory form of GBS was seen in 71 and 115 children. Based on the Hadden criteria, a demyelinating pattern was noted in 57 children; axonal in 37; Inexcitable in 84 and Equivocal in 8 children. The sensitivity of the various criteria ranged from 71% to 100% for demyelination, 97% to 100% for axonal. The degree of agreement using Hadden and Rajabally criteria for Equivocal subtypes was 0.93. CONCLUSIONS: The Rajabally criteria showed the best sensitivity, specificity and diagnostic accuracy for electrodiagnosis of GBS in children when compared against Hadden criteria.

Biotin-Thiamine-Responsive Basal Ganglia Disease in Children: A Treatable Neurometabolic Disorder.

Biotin-thiamine-responsive basal ganglia disease is a rare, autosomal recessive, treatable, neurometabolic disorder associated with biallelic pathogenic variations in the SLC19A3 gene. The condition may present as an early-childhood encephalopathy, an early-infantile lethal encephalopathy with lactic acidosis, with or without infantile spasms, or a late-onset Wernicke-like encephalopathy. The key radiological features are bilateral, symmetrical lesions in the caudate, putamen, and medial thalamus, with variable extension into the brain stem, cerebral cortex, and cerebellum. Treatment is life long and includes initiation of high dose biotin and thiamine. Genetic testing confirms the diagnosis. The prognosis depends on the time from diagnosis to the time of vitamin supplementation. The genotype-phenotype correlations are not clear yet, but the early infantile phenotype portends a poorer prognosis. We provide a brief overview of the disorder and emphasize the initiation of high-dose biotin and thiamine in infants and children with unexplained encephalopathy and basal ganglia involvement.

Bone density and bone health alteration in boys with Duchenne Muscular Dystrophy: a prospective observational study.

OBJECTIVES: Boys with Duchenne Muscular Dystrophy (DMD) are at increased risk for compromised bone health, manifesting as low-impact trauma long bone fractures and vertebral compression fractures. METHODS: In a prospective observational study, we studied bone health parameters in North Indian boys with DMD. We consecutively enrolled ambulatory boys with DMD on glucocorticoid therapy. Bone health was evaluated with X-ray spine, Dual-energy X-ray absorptiometry (DXA), serum calcium, vitamin D3 (25[OH]D), 1,25-dihyroxyvitamin D3 (1,25[OH]2D3), serum osteocalcin, osteopontin, and N terminal telopeptide of type 1 collagen (Ntx) levels. RESULTS: A total of 76 boys with DMD were enrolled. The median age was 8.5 (interquartile range [IQR] 7.04-10.77) years. Among these, seven (9.2%) boys had long bone fractures, and four (5.3%) had vertebral compression fractures. Fifty-four (71%) boys underwent DXA scan, and among these 31 (57%) had low bone mineral density (BMD, ≤-2 z-score) at the lumbar spine. The mean BMD z-score at the lumbar spine was -2.3 (95% confidence interval [CI] = -1.8, -2.8), and at the femoral neck was -2.5 (95% CI = -2, -2.9). 25(OH)D levels were deficient in 68 (89.5%, n=76) boys, and 1,25(OH)2D3 levels were deficient in all. Mean serum osteocalcin levels were 0.68 ± 0.38 ng/mL (n=54), serum osteopontin levels were 8.6 ± 4.6 pg/mL (n=54) and serum Ntx levels were 891 ± 476 nmol/L (n=54). Boys with low BMD received glucocorticoids for longer duration, in comparison to those with normal BMD (median, IQR [16.9 (6-34) months vs. 7.8 (4.8-13.4) months]; p=0.04). CONCLUSIONS: Bone health is compromised in North Indian boys with DMD. BMD at the lumbar spine is reduced in more than half of boys with DMD and nearly all had vitamin D deficiency on regular vitamin D supplements. Longer duration of glucocorticoid therapy is a risk factor for low BMD in our cohort.

Etiologic Profile of Childhood Stroke from North India: Is It Different from Developed World?

OBJECTIVE: To describe the etiology of childhood arterial-ischemic stroke from a developing country and assess short-term neurologic outcome. METHODS: Prospective observational study. Consecutive children between the age of >28 days to <12 years, admitted with the diagnosis of arterial-ischemic stroke were enrolled during the study period from January 2017 to December 2018. Short-term neurologic outcome was assessed with Pediatric Cerebral Performance Category (PCPC) scale and Pediatric Stroke Outcome Measure (PSOM). RESULTS: We enrolled 76 children with arterial-ischemic stroke, with a median age of 24 months (interquartile range 12-69), and 43 (57%) were boys. The most common risk factor for childhood arterial-ischemic stroke was arteriopathy in 59 (77%), followed by cardiovascular disorder in 12 (16%) children. Among 59 children with arteriopathy, 32 (42%) had infection-associated arteriopathies, 10 (13%) had mineralizing angiopathy, 10 (13%) had moyamoya disease. Pediatric stroke risk factors were classified according to Pediatric Stroke Classification and CASCADE primary classification. Short-term neurologic outcome was assessed at 3 months in 62 (82%) survivors. Among stroke survivors, 33 (61%) had sensory-motor deficits, and 24 (39%) had severe neurologic disability (PCPC ≥ 4). The presence of fever, encephalopathy, low Glasgow coma score at presentation, seizures, and infection-associated arteriopathy predicted severe neurologic disability at follow-up. CONCLUSION: The risk factors for pediatric arterial-ischemic stroke are different from developed countries in our cohort. Infection-associated arteriopathies, mineralizing angiopathy, and moyamoya disease are the most common risk factors in our cohort. Two-thirds of pediatric stroke survivors have neurologic disability at short-term follow-up.

The Expanding Spectrum of Dystrophinopathies: HyperCKemia to Manifest Female Carriers.

Background: X-linked dystrophinopathies have a wide spectrum of manifestation. The most common forms are severe Duchenne muscular dystrophy (DMD) and Becker's muscular dystrophy (BMD). However, less common manifestations are isolated cardiomyopathy, myalgia, cramps, rhabdomyolysis, hyperCKemia, and manifest female carriers. Materials and Methods: This case series is a part of an ongoing long-term prospective cohort of children with DMD and BMD from the year 2013. The clinical details are maintained in the clinic files and standard management protocols are followed. For this case series, clinical details were collected from the clinic files and recorded on a case record proforma. Details of cardiology, radiology, and genetic investigations were collected. Results: We report cases of classical DMD, BMD, manifest female carrier with proximal pelvic girdle weakness, a female carrier with isolated dilated cardiomyopathy, and infantile-onset asymptomatic hyperCKemia. We also report less common but notable clinical presentations of DMD, autism, intellectual disability, epilepsy, and asymptomatic transaminitis. Conclusions: It is important for clinicians to be aware of these less common clinical presentations for prompt diagnosis, and to avoid unnecessary investigations. Here, we report the clinical spectrum of dystrophinopathies seen in pediatric neuromuscular clinic and emphasize the variability and expanding knowledge about different manifestations of dystrophinopathies.

Consensus guidelines for the diagnosis and management of pyridoxine-dependent epilepsy due to α-aminoadipic semialdehyde dehydrogenase deficiency.

Pyridoxine-dependent epilepsy (PDE-ALDH7A1) is an autosomal recessive condition due to a deficiency of α-aminoadipic semialdehyde dehydrogenase, which is a key enzyme in lysine oxidation. PDE-ALDH7A1 is a developmental and epileptic encephalopathy that was historically and empirically treated with pharmacologic doses of pyridoxine. Despite adequate seizure control, most patients with PDE-ALDH7A1 were reported to have developmental delay and intellectual disability. To improve outcome, a lysine-restricted diet and competitive inhibition of lysine transport through the use of pharmacologic doses of arginine have been recommended as an adjunct therapy. These lysine-reduction therapies have resulted in improved biochemical parameters and cognitive development in many but not all patients. The goal of these consensus guidelines is to re-evaluate and update the two previously published recommendations for diagnosis, treatment, and follow-up of patients with PDE-ALDH7A1. Members of the International PDE Consortium initiated evidence and consensus-based process to review previous recommendations, new research findings, and relevant clinical aspects of PDE-ALDH7A1. The guideline development group included pediatric neurologists, biochemical geneticists, clinical geneticists, laboratory scientists, and metabolic dieticians representing 29 institutions from 16 countries. Consensus guidelines for the diagnosis and management of patients with PDE-ALDH7A1 are provided.

Seven novel genetic variants in a North Indian cohort with classical homocystinuria.

Classical homocystinuria is the most common cause of isolated homocystinuria. The variants of the CBS gene remain unidentified in Indian children with this disorder. Based on the hallmark clinical features, family history, and/or biochemical clues for classical homocystinuria, 16 children below the age of 18 years were evaluated by Sanger sequencing of the coding exons of CBS gene with flanking intronic regions. The common C677T variant of the MTHFR gene was also screened by restriction fragment length polymorphism. Fifteen children were clinically suspected of having classical homocystinuria and one asymptomatic child with positive family history. Only seven children had biochemical features of classical homocystinuria. Sanger sequencing of the CBS gene confirmed 15 different pathogenic or likely pathogenic variants in 14 cases. Of these, seven variants were novel (three frameshift deletions, two nonsense, one missense, one splice site variant) and were predicted to be deleterious by Mutation Taster software. Seven cases were homozygous, another six were compound heterozygous, and one case was single heterozygous in the study. None of the three most frequent mutations reported worldwide viz., I278T, G307S, and IVS 11-2A>C were found in our cohort. No variants were detected in the exons 2, 8, 12, and 14 as compared to reported literature. Eleven out of 15 variants were associated with the conserved catalytic domain of the CBS polypeptide. The MTHFR polymorphism C677T was observed in heterozygous state in six cases. Our study reports the detailed genotype and seven novel variants in the CBS gene, causing classical homocystinuria in Indian children. The genetic analysis will help to offer accurate genetic counseling, prenatal diagnosis, and development of mutation-based novel therapeutic strategies.