Etiological involvement of KCND1 variants in an X-linked neurodevelopmental disorder with variable expressivity.

Utilizing trio whole-exome sequencing and a gene matching approach, we identified a cohort of 18 male individuals from 17 families with hemizygous variants in KCND1, including two de novo missense variants, three maternally inherited protein-truncating variants, and 12 maternally inherited missense variants. Affected subjects present with a neurodevelopmental disorder characterized by diverse neurological abnormalities, mostly delays in different developmental domains, but also distinct neuropsychiatric signs and epilepsy. Heterozygous carrier mothers are clinically unaffected. KCND1 encodes the α-subunit of Kv4.1 voltage-gated potassium channels. All variant-associated amino acid substitutions affect either the cytoplasmic N- or C-terminus of the channel protein except for two occurring in transmembrane segments 1 and 4. Kv4.1 channels were functionally characterized in the absence and presence of auxiliary ß subunits. Variant-specific alterations of biophysical channel properties were diverse and varied in magnitude. Genetic data analysis in combination with our functional assessment shows that Kv4.1 channel dysfunction is involved in the pathogenesis of an X-linked neurodevelopmental disorder frequently associated with a variable neuropsychiatric clinical phenotype.

Prognostic relevance of quantitative and longitudinal MOG antibody testing in patients with MOGAD: a multicentre retrospective study.

BACKGROUND: IgG antibodies against myelin oligodendrocyte glycoprotein (MOG-IgG) define a subset of associated disorders (myelin oligodendrocyte glycoprotein associated disorders (MOGAD)) that can have a relapsing course. However, information on relapse predictors is scarce. The utility of retesting MOG-IgG over time and measuring their titres is uncertain. We aimed to evaluate the clinical relevance of longitudinal MOG-IgG titre measurement to predict relapses in patients with MOGAD. METHODS: In this retrospective multicentre Italian cohort study, we recruited patients with MOGAD and available longitudinal samples (at least one >3 months after disease onset) and tested them with a live cell-based assay with endpoint titration (1:160 cut-off). Samples were classified as 'attack' (within 30 days since a disease attack (n=59, 17%)) and 'remission' (≥31 days after attack (n=295, 83%)). RESULTS: We included 102 patients with MOGAD (57% adult and 43% paediatric) with a total of 354 samples (83% from remission and 17% from attack). Median titres were higher during attacks (1:1280 vs 1:640, p=0.001). Median onset titres did not correlate with attack-related disability, age or relapses. Remission titres were higher in relapsing patients (p=0.02). When considering the first remission sample available for each patient, titres >1:2560 were predictors of relapsing course in survival (log rank, p<0.001) and multivariate analysis (p<0.001, HR: 10.9, 95% CI 3.4 to 35.2). MOG-IgG seroconversion to negative was associated with a 95% relapse incidence rate reduction (incidence rate ratio: 0.05, p<0.001). CONCLUSIONS: Persistent MOG-IgG positivity and high remission titres are associated with an increased relapse risk. Longitudinal MOG-IgG titres could be useful to stratify patients to be treated with long term immunosuppression.

Interstitial 2q24.2q24.3 Microdeletion: Two New Cases with Similar Clinical Features with the Exception of Profound Deafness.

Interstitial 2q24.2q24.3 microdeletions are rare cytogenetic aberrations associated with heterogeneous clinical features depending on the size of the deletion. Here, we describe 2 patients with overlapping de novo 2q24.2q24.3 deletions, characterized by array-CGH. This is the smallest 2q24.2q24.3 region of overlap described in the literature encompassing only 9 genes (SLC4A10, DPP4, GCG, FAP, IFIH1, GCA, KCNH7, FIGN, GRB14). We focused our attention on SLC4A10, DPP4, and KCNH7, genes associated with neurological features. Our patients presented similar features: intellectual disability, developmental and language delay, hypotonia, joint laxity, and dysmorphic features. Only patient 2 showed profound deafness and also carried a heterozygous mutation of the GJB2 gene responsible for autosomal recessive deafness 1A (DFNB1A: OMIM 220290). Could the disruption of a gene present in the 2q24.2q24.3 deleted region be responsible for her profound hearing loss?

The spectrum of intermediate SCN8A-related epilepsy.

OBJECTIVE: Pathogenic variants in SCN8A have been associated with a wide spectrum of epilepsy phenotypes, ranging from benign familial infantile seizures (BFIS) to epileptic encephalopathies with variable severity. Furthermore, a few patients with intellectual disability (ID) or movement disorders without epilepsy have been reported. The vast majority of the published SCN8A patients suffer from severe developmental and epileptic encephalopathy (DEE). In this study, we aimed to provide further insight on the spectrum of milder SCN8A-related epilepsies. METHODS: A cohort of 1095 patients were screened using a next generation sequencing panel. Further patients were ascertained from a network of epilepsy genetics clinics. Patients with severe DEE and BFIS were excluded from the study. RESULTS: We found 36 probands who presented with an SCN8A-related epilepsy and normal intellect (33%) or mild (61%) to moderate ID (6%). All patients presented with epilepsy between age 1.5 months and 7 years (mean = 13.6 months), and 58% of these became seizure-free, two-thirds on monotherapy. Neurological disturbances included ataxia (28%) and hypotonia (19%) as the most prominent features. Interictal electroencephalogram was normal in 41%. Several recurrent variants were observed, including Ile763Val, Val891Met, Gly1475Arg, Gly1483Lys, Phe1588Leu, Arg1617Gln, Ala1650Val/Thr, Arg1872Gln, and Asn1877Ser. SIGNIFICANCE: With this study, we explore the electroclinical features of an intermediate SCN8A-related epilepsy with mild cognitive impairment, which is for the majority a treatable epilepsy.

Tubulin-related cerebellar dysplasia: definition of a distinct pattern of cerebellar malformation.

OBJECTIVE: To determine the neuroimaging pattern of cerebellar dysplasia (CD) and other posterior fossa morphological anomalies associated with mutations in tubulin genes and to perform clinical and genetic correlations. METHODS: Twenty-eight patients harbouring 23 heterozygous pathogenic variants (ten novel) in tubulin genes TUBA1A (n = 10), TUBB2B (n = 8) or TUBB3 (n = 5) were studied by a brain MRI scan performed either on a 1.5 T (n = 10) or 3 T (n = 18) MR scanner with focus on the posterior fossa. RESULTS: Cerebellar anomalies were detected in 24/28 patients (86%). CD was recognised in 19/28 (68%) including cortical cerebellar dysplasia (CCD) in 18/28, either involving only the cerebellar hemispheres (12/28) or associated with vermis dysplasia (6/28). CCD was located only in the right hemisphere in 13/18 (72%), including four TUBB2B-, four TUBB3- and five TUBA1A-mutated patients, while in the other five TUBA1A cases it was located only in the left hemisphere or in both hemispheres. The postero-superior region of the cerebellar hemispheres was most frequently affected. CONCLUSIONS: The cerebellar involvement in tubulinopathies shows specific features that may be labelled as 'tubulin-related CD'. This pattern is unique and differs from other genetic causes of cerebellar dysplasia. KEY POINTS: • Cortical cerebellar dysplasia without cysts is suggestive of tubulin-related disorder. • Cerebellar dysplasia in tubulinopathies shows specific features labelled as 'tubulin-related CD'. • Focal and unilateral involvement of cerebellar hemispheres has important implications for counselling.

Long-term outcome and need of re-operation in gastro-esophageal reflux surgery in children.

BACKGROUND: Fundoplication is considered a mainstay in the treatment of gastro-esophageal reflux. However, the literature reports significant recurrences and limited data on long-term outcome. AIMS: To evaluate our long-term outcomes of antireflux surgery in children and to assess the results of redo surgery. METHODS: We retrospectively analyzed all patients who underwent Nissen fundoplication in 8 consecutive years. Reiterative surgery was indicated only in case of symptoms and anatomical alterations. A follow-up study was carried out to analyzed outcome and patients' Visick score assessed parents' perspective. RESULTS: Overall 162 children were included for 179 procedures in total. Median age at first intervention was 43 months. Comorbidities were 119 (73 %), particularly neurological impairments (73 %). Redo surgery is equal to 14 % (25/179). Comorbidities were risk factors to Nissen failure (p = 0.04), especially children suffering neurological impairment with seizures (p = 0.034). Follow-up datasets were obtained for 111/162 = 69 % (median time: 51 months). Parents' perspectives were excellent or good in 85 %. CONCLUSIONS: A significant positive impact of redo Nissen intervention on the patient's outcome was highlighted; antireflux surgery is useful and advantageous in children and their caregivers. Children with neurological impairment affected by seizures represent significant risk factors.

Structural brain abnormalities in Pallister-Killian syndrome: a neuroimaging study of 31 children.

BACKGROUND: Pallister-Killian syndrome (PKS) is a rare genetic disorder caused by mosaic tetrasomy of 12p with wide neurological involvement. Intellectual disability, developmental delay, behavioral problems, epilepsy, sleep disturbances, and brain malformations have been described in most individuals, with a broad phenotypic spectrum. This observational study, conducted through brain MRI scan analysis on a cohort of patients with genetically confirmed PKS, aims to systematically investigate the neuroradiological features of this syndrome and identify the possible existence of a typical pattern. Moreover, a literature review differentiating the different types of neuroimaging data was conducted for comparison with our population. RESULTS: Thirty-one individuals were enrolled (17 females/14 males; age range 0.1-17.5 years old at first MRI). An experienced pediatric neuroradiologist reviewed brain MRIs, blindly to clinical data. Brain abnormalities were observed in all but one individual (compared to the 34% frequency found in the literature review). Corpus callosum abnormalities were found in 20/30 (67%) patients: 6 had callosal hypoplasia; 8 had global hypoplasia with hypoplastic splenium; 4 had only hypoplastic splenium; and 2 had a thin corpus callosum. Cerebral hypoplasia/atrophy was found in 23/31 (74%) and ventriculomegaly in 20/31 (65%). Other frequent features were the enlargement of the cisterna magna in 15/30 (50%) and polymicrogyria in 14/29 (48%). Conversely, the frequency of the latter was found to be 4% from the literature review. Notably, in our population, polymicrogyria was in the perisylvian area in all 14 cases, and it was bilateral in 10/14. CONCLUSIONS: Brain abnormalities are very common in PKS and occur much more frequently than previously reported. Bilateral perisylvian polymicrogyria was a main aspect of our population. Our findings provide an additional tool for early diagnosis.Further studies to investigate the possible correlations with both genotype and phenotype may help to define the etiopathogenesis of the neurologic phenotype of this syndrome.

Comparison of Qualitative and Quantitative Analyses of MR-Arterial Spin Labeling Perfusion Data for the Assessment of Pediatric Patients with Focal Epilepsies.

The role of MR Arterial-Spin-Labeling Cerebral Blood Flow maps (ASL-CBF) in the assessment of pediatric focal epilepsy is still debated. We aim to compare the Seizure Onset Zone (SOZ) detection rate of three methods of evaluation of ASL-CBF: 1) qualitative visual (qCBF), 2) z-score voxel-based quantitative analysis of index of asymmetry (AI-CBF), and 3) z-score voxel-based cluster analysis of the quantitative difference of patient's CBF from the normative data of an age-matched healthy population (cCBF). Interictal ASL-CBF were acquired in 65 pediatric patients with focal epilepsy: 26 with focal brain lesions and 39 with a normal MRI. All hypoperfusion areas visible in at least 3 contiguous images of qCBF analysis were identified. In the quantitative evaluations, clusters with a significant z-score AI-CBF ≤ −1.64 and areas with a z-score cCBF ≤ −1.64 were considered potentially related to the SOZ. These areas were compared with the SOZ defined by the anatomo-electro-clinical data. In patients with a positive MRI, SOZ was correctly identified in 27% of patients using qCBF, 73% using AI-CBF, and 77% using cCBF. In negative MRI patients, SOZ was identified in 18% of patients using qCBF, in 46% using AI-CBF, and in 64% using cCBF (p < 0.001). Quantitative analyses of ASL-CBF maps increase the detection rate of SOZ compared to the qualitative method, principally in negative MRI patients.

Multimodal approach in the pre-surgical evaluation of focal epilepsy surgery candidates: how far are we from a non-invasive ESI-based "sourcectomy"?

The management of drug-resistant patients with focal epilepsy is often challenging. Surgery is recognised as a useful and effective treatment option. The identification of the epileptogenic zone relies on the integration of clinical, neurophysiological, and neuroimaging findings. The role of non-invasive functional neuroimaging techniques has been reported to add diagnostic accuracy to first-line evaluations, avoiding invasive presurgical examinations in selected cases. In this view, we report the case of a 16-year-old male suffering from drug-resistant focal epilepsy with episodes rarely evolving to a bilateral tonic-clonic seizure. Conventional 1.5T and 3T MRI were considered uninformative. Based on electro-clinical data, focal cortical dysplasia was suspected. The epileptogenic zone was identified with the integration of further non-invasive functional neuroimaging techniques ([18F]-fluorodeoxyglucose positron emission tomography and arterial spin labelling), where electrical source imaging played the main role. All techniques pointed towards a cortical region, where a 7T brain MRI identified a signal alteration consistent with focal cortical dysplasia. A tailored resection of the lesion located in the inferior frontal sulcus was performed, guided by intraoperative electrocorticography (strip and depth electrodes). Postoperative seizure freedom was achieved. The histopathology confirmed the suspicion of focal cortical dysplasia type IIa. With this case report, we highlight the importance of a multimodal approach in the presurgical evaluation of candidates for epilepsy surgery, which, in selected cases, may allow invasive procedures, such as stereo-EEG, to be avoided in the investigation of the epileptogenic zone. Moreover, we underline the pivotal role of EEG source imaging, especially when focal cortical dysplasia is suspected.

Total oesophago-gastric dissociation in neurologically impaired children: Laparoscopic vs robotic approach.

PURPOSE: To evaluate and compare the feasibility and short-term results of laparoscopic and robotic total oesophago-gastric dissociation (TOGD) with a Roux-en-Y oesophago-jejunostomy. Minimal invasive surgery has multiple advantages in neurologically impaired patients. Robotic approach has overcome disadvantages linked to laparoscopy, in particular, referring to the surgeon fatigue. METHODS: A retrospective study comparing five laparoscopic and five robotic TOGD was conducted between February and October 2016 in Giannina Gaslini Children's Hospital and Section of Pediatric Surgery of Siena. Neurologically impaired children scheduled for TOGD were included. Age, sex, weight, symptomatology, presence of epilepsy, and preoperative X-ray contrast were considered. Operative time, hospital stay, postoperative complications, redo surgery, nutrition rehabilitation, and X-ray contrast study after 5 days and after 1 month from the intervention were recorded. RESULTS: In our series, there were no intraoperative complications, no conversions to open surgery, and no vagal lesions. In two of five robotic cases, a pyloroplasty was necessary. The median operative time was statistically longer in the robotic group. One dehiscence in the robotic group was recorded, and no dumping episodes occurred. No statistical differences in terms of complications were detected. CONCLUSION: TOGD is feasible both with laparoscopic and robotic-assisted surgery with similar results. Robotic approach is considered feasible. At the same time, high laparoscopic skills allow to reach the same results as robotic approach with shorter operative time.

Cell-based assays for the detection of MOG antibodies: a comparative study.

BACKGROUND: The detection of antibodies to myelin oligodendrocyte glycoprotein (MOG) is fundamental for the identification of MOG antibody-associated disorders (MOGAD), and the differential diagnosis of acquired demyelinating syndromes of the CNS, among which multiple sclerosis (MS). We compared the diagnostic performance of four cell-based assays (CBAs) for their detection. METHODS: Consecutive sera from 204 patients with 'possible MOGAD' (55), MS (112), and other neurological disorders (OND, 37) were tested for MOG-IgG with a live-CBA with anti-heavy-and-light chain secondary-antibody (LCBA-IgGH+L), and a live-CBA for IgG1 (LCBA-IgG1). A subgroup of 71 patients was additionally tested with a live-CBA with anti-Fcγ secondary-antibody (LCBA-IgGFcγ), and a commercial fixed-CBA with anti-Fcγ secondary-antibody (FCBA-IgGFcγ). RESULTS: Fifty-seven/204 patients (27.9%) were MOG-IgG-positive. Sensitivity was 89.1% (CI:77.8-95.9) and specificity 93.3% (CI:88.0-96.7) for LCBA-IgGH+L, and 74.6% (CI:61.0-85.3) and 100% (CI:97.6-100) for LCBA-IgG1. Eighteen of 57 (31%) samples showed discrepant results (all negative on LCBA-IgG1); of these, three with 'possible MOGAD' showed high-titer MOG-IgG (≥ 1:640), and positivity for MOG-IgG2, whereas 15/18 had low-titer MOG-IgG (1:160/1:320) and mixed diagnoses (5 'possible MOGAD', 6 MS, 4 OND). In the subgroup analysis, sensitivity was 92.3% (CI:79.1-98.4) and specificity 97.0% (CI:83.8-99.9) for LCBA-IgGFcγ, and 87.2% (CI:72.6-95.7) and 97.0% (CI:83.8-99.9) for FCBA-IgGFcγ. CONCLUSIONS: LCBA-IgG1 showed the highest specificity but can miss MOG-IgG2 reactivities, whose meaning warrants further investigations. Titration of samples tested with LCBA-IgGH+L/ IgGFcγ is important for meaningful interpretation of the results. In the subgroup analysis, LCBA-IgGFcγ yielded the highest accuracy, and FCBA-IgGFcγ good specificity, but it was at risk of false-negative results.

Acute hyperkinetic movement disorders in Italian paediatric emergency departments.

INTRODUCTION: Limited data exist on epidemiology, clinical presentation and management of acute hyperkinetic movement disorders (AHMD) in paediatric emergency departments (pED). METHODS: We retrospectively analysed a case series of 256 children (aged 2 months to 17 years) presenting with AHMD to the pEDs of six Italian tertiary care hospitals over a 2-year period (January 2012 to December 2013). RESULTS: The most common type of AHMD was tics (44.5%), followed by tremors (21.1%), chorea (13.7%), dystonia (10.2%), myoclonus (6.3%) and stereotypies (4.3%). Neuropsychiatric disorders (including tic disorders, psychogenic movement disorders and idiopathic stereotypies) were the most represented cause (51.2%). Inflammatory conditions (infectious and immune-mediated neurological disorders) accounted for 17.6% of the cases whereas non-inflammatory disorders (including drug-induced AHMDs, genetic/metabolic diseases, paroxysmal non-epileptic movements and idiopathic AHMDs) accounted for 31.2%. Neuropsychiatric disorders prevailed among preschoolers and schoolers (51.9% and 25.2%, respectively), non-inflammatory disorders were more frequent in infants and toddlers (63.8%), whereas inflammatory conditions were more often encountered among schoolers (73.3%). In 5 out of 36 Sydenham's chorea (SC) cases, tics were the presentation symptom on admission to emergency department (ED), highlighting the difficulties in early diagnosis of SC. Inflammatory disorders were associated with a longer hospital stay and a greater need of neuroimaging test compared with other disorders. CONCLUSIONS: This study provides the first large sample of paediatric patients presenting to the ED for AHMDs, helping to elucidate the epidemiology, aetiology and clinical presentation of these disorders.

Robotic-Assisted Minimally Invasive Total Esophagogastric Dissociation for Children with Severe Neurodisability.

BACKGROUND: Around 70% of children with neurodisability (ND) present pharyngeal neuromuscular incoordination and severe gastroesophageal reflux disease (GORD). METHODS: This is a pilot study with the Robotic-assisted minimally invasive total esophagogastric dissociation (TOGD). RESULTS: We included 4 patients, 2 males and 2 females, with ND and severe GORD refractory to medical treatment. CONCLUSIONS: Pharmacological management of GORD is often unsuccessful and antireflux surgery is common, but it has a high failure rate with symptom recurrence, requiring re-do surgery. TOGD is a good option for these patients.

Gluten Psychosis: Confirmation of a New Clinical Entity.

Non-celiac gluten sensitivity (NCGS) is a syndrome diagnosed in patients with symptoms that respond to removal of gluten from the diet, after celiac disease and wheat allergy have been excluded. NCGS has been related to neuro-psychiatric disorders, such as autism, schizophrenia and depression. A singular report of NCGS presenting with hallucinations has been described in an adult patient. We report a pediatric case of a psychotic disorder clearly related to NCGS and investigate the causes by a review of literature. The pathogenesis of neuro-psychiatric manifestations of NCGS is unclear. It has been hypothesized that: (a) a "leaky gut" allows some gluten peptides to cross the intestinal membrane and the blood brain barrier, affecting the endogenous opiate system and neurotransmission; or (b) gluten peptides may set up an innate immune response in the brain similar to that described in the gut mucosa, causing exposure from neuronal cells of a transglutaminase primarily expressed in the brain. The present case-report confirms that psychosis may be a manifestation of NCGS, and may also involve children; the diagnosis is difficult with many cases remaining undiagnosed. Well-designed prospective studies are needed to establish the real role of gluten as a triggering factor in neuro-psychiatric disorders.

RORB gene and 9q21.13 microdeletion: report on a patient with epilepsy and mild intellectual disability.

Copy number variants represent an important cause of neurodevelopmental disorders including epilepsy, which is genetically determined in 40% of cases. Epilepsy is caused by chromosomal imbalances or mutations in genes encoding subunits of neuronal voltage- or ligand-gated ion channels or proteins related to neuronal maturation and migration during embryonic development. Here, we report on a girl with mild intellectual disability and idiopathic partial epilepsy. Array-CGH analysis showed a 1.040 Mb de novo interstitial deletion at 9q21.13 band encompassing only four genes, namely RORB, TRPM6, NMRK1, OSTF1, two open reading frames (C9orf40, C9orf41), and a microRNA (MIR548H3). RORB encodes a nuclear receptor highly expressed in the retina, cortex, and thalamus. We hypothesize its role in producing the phenotype of our patient and compare this case with other ones previously reported in the literature to better identify a genotype-phenotype correlation.

Neuropsychological profile and clinical effects of arginine treatment in children with creatine transport deficiency.

BACKGROUND: SLC6A8, an X-linked gene, encodes the creatine transporter (CRTR) and its mutations lead to cerebral creatine (Cr) deficiency which results in mental retardation, speech and language delay, autistic-like behaviour and epilepsy (CRTR-D, OMIM 300352). CRTR-D represents the most frequent Cr metabolism disorder but, differently from Cr synthesis defects, that are partially reversible by oral Cr supplementation, does not respond to Cr treatment even if precociously administrated. The precursors of Cr are the non-essential amino acids Glycine (Gly) and Arginine (Arg), which have their own transporters at the brain-blood barrier level and, therefore, their supplementation appears an attractive and feasible therapeutic option aimed at stimulating Cr endogenous synthesis and, in this way, at overcoming the block of Cr transport within the brain. However, until now the effects of Arg and/or Gly supplementation on Cr brain levels and behaviour have been controversial. METHODS: In this study five Italian male patients affected by CRTR-D were supplemented with oral L-Arg at a dosage of 300 mg/kg/day divided into 3 doses, for 24-36 months. Biochemical and plasmatic amino acids examinations and thyroid hormone dosages were periodically performed. Moreover, Proton and Phosphorus Magnetic Resonance Spectroscopy (MRS) was monitored during follow-up in concurrence with neuropsychological evaluations. RESULTS: During L-Arg treatment a clinical improvement in motor skills and to a lesser extent in communication and attention was observed. In addition, all patients had a reduction in the number and frequency of epileptic seizures. Daily living skills appeared also to be positively influenced by L-Arg treatment. Moreover, Total Cr and especially PhosphoCr, evaluated by proton and phosphorus spectroscopy, showed a mild increase, although well below the normal range. CONCLUSION: This study provides information to support the effectiveness of L-Arg supplement treatment in CTRT-D patients; in fact the syndromic pattern of cognitive and linguistic deficit presented by CRTR-D patients was partially altered by L-Arg supplementation especially at a qualitative clinical level. Oral L-Arg may represent not only a protective factor towards a further cognitive decline, but can lead to the acquisition of new skills.