Evaluation of the Patients with the Diagnosis of Pontocerebellar Hypoplasia: A Multicenter National Study.

Pontocerebellar hypoplasia (PCH) is a heterogeneous group of neurodegenerative disorders characterized by hypoplasia and degeneration of the cerebellum and pons. We aimed to identify the clinical, laboratory, and imaging findings of the patients with diagnosed PCH with confirmed genetic analysis. We collected available clinical data, laboratory, and imaging findings in our retrospective multicenter national study of 64 patients with PCH in Turkey. The genetic analysis included the whole-exome sequencing (WES), targeted next-generation sequencing (NGS), or single gene analysis. Sixty-four patients with PCH were 28 female (43.8%) and 36 (56.3%) male. The patients revealed homozygous mutation in 89.1%, consanguinity in 79.7%, pregnancy at term in 85.2%, microcephaly in 91.3%, psychomotor retardation in 98.4%, abnormal neurological findings in 100%, seizure in 63.8%, normal biochemistry and metabolic investigations in 92.2%, and dysmorphic findings in 51.2%. The missense mutation was found to be the most common variant type in all patients with PCH. It was detected as CLP1 (n = 17) was the most common PCH related gene. The homozygous missense variant c.419G > A (p.Arg140His) was identified in all patients with CLP1. Moreover, all patients showed the same homozygous missense variant c.919G > T (p.A307S) in TSEN54 group (n = 6). In Turkey, CLP1 was identified as the most common causative gene with the identical variant c.419G > A; p.Arg140His. The current study supports that genotype data on PCH leads to phenotypic variability over a wide phenotypic spectrum.

Effectiveness and Safety of Epilepsy Surgery for Pediatric Patients with Intractable Epilepsy: A Clinical Retrospective Study from a Single-Center Experience.

INTRODUCTION: Pediatric epilepsy surgery is an effective treatment modality for patients with drug-resistant epilepsy (DRE). Early pediatric surgery yields favorable results for DRE in terms of seizure control and neurophysiological outcome. In this study, pediatric patients were categorized based on their age (above 3 years old and below 3 years old) to demonstrate the effectiveness and safety of surgical procedures. METHODS: In this retrospective, single-center study, 60 pediatric patients who underwent epilepsy surgery at Istanbul Faculty of Medicine between 2002 and 2018 were evaluated. Overall morbidity and mortality rates, as well as seizure outcomes of the patients, were assessed and compared based on two age groups: those aged 3 years old or younger and those older than 3 years old. The effectiveness of invasive monitoring was also evaluated in relation to pathological results. The postoperative seizure outcome rates were evaluated using Engel's classification, with an average follow-up period of 8.7 years. RESULTS: Out of the total number of patients, 47 (78.4%) underwent resective surgery, while 13 (21.6%) had palliative surgery. Ten patients (16.6%) had invasive monitoring. Among all patients, 34 were classified as Engel I and II (56.6%), while 26 were classified as Engel III and IV (43.4%) postoperatively. 47% of patients who were under 3 years old, 60.4% of patients who were over 3 years old, and 50% of patients who underwent invasive monitoring had a favorable seizure outcome (Engel I-II). Postoperative morbidity and mortality rates were 35% (n = 21) and 1.6% (n = 1), respectively. CONCLUSION: Pediatric epilepsy surgery is an important treatment modality for preserving cognitive abilities and providing effective treatment for pediatric DRE. In our study, we claim that both invasive monitoring and epilepsy surgery lead to favorable seizure outcomes for all age groups. Further clinical studies should be conducted to provide more reliable data on the safety and effectiveness of the surgery, particularly in patients under the age of three.

Shared Biological Pathways and Processes in Patients with Intellectual Disability: A Multicenter Study.

BACKGROUND: Although the underlying genetic causes of intellectual disability (ID) continue to be rapidly identified, the biological pathways and processes that could be targets for a potential molecular therapy are not yet known. This study aimed to identify ID-related shared pathways and processes utilizing enrichment analyses. METHODS: In this multicenter study, causative genes of patients with ID were used as input for Disease Ontology (DO), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes enrichment analysis. RESULTS: Genetic test results of 720 patients from 27 centers were obtained. Patients with chromosomal deletion/duplication, non-ID genes, novel genes, and results with changes in more than one gene were excluded. A total of 558 patients with 341 different causative genes were included in the study. Pathway-based enrichment analysis of the ID-related genes via ClusterProfiler revealed 18 shared pathways, with lysine degradation and nicotine addiction being the most common. The most common of the 25 overrepresented DO terms was ID. The most frequently overrepresented GO biological process, cellular component, and molecular function terms were regulation of membrane potential, ion channel complex, and voltage-gated ion channel activity/voltage-gated channel activity, respectively. CONCLUSION: Lysine degradation, nicotine addiction, and thyroid hormone signaling pathways are well-suited to be research areas for the discovery of new targeted therapies in ID patients.

Recurrent Blistering Skin Lesions and Reversible Monocular Abducens Paralysis in a Patient with CD59 Deficiency.

Congenital CD59 deficiency is an autosomal recessive disease characterized by mild-to-moderate chronic intravascular hemolysis, relapsing demyelinating peripheral neuropathies, and recurrent ischemic central nervous system strokes. We report a 2-year-old Turkish girl with a history of two episodes of Guillain-Barré syndrome-like acute weakness, reversible monocular abducens paralysis, and recurrent blistering skin lesions during periods of upper respiratory tract infections. Reversible monocular abducens palsy and recurrent blistering skin lesions have not been reported previously in cases of congenital CD59 deficiency.

Clinical and electrophysiological predictors of behavioral disorders in patients with benign childhood epilepsy with centrotemporal spikes.

PURPOSE: Long-term seizure and developmental outcomes of benign childhood epilepsy with centrotemporal spikes (BECTS) are thought to be good. Studies have shown that behavioral disorders may accompany BECTS. We aimed to investigate the frequency of behavioral disorders in patients with BECTS and evaluate their relationship to epilepsy features. METHODS: Data for 41 patients with BECTS followed up at our clinic between December 2019 and June 2020 were analyzed. Behavioral disorders and intelligence were evaluated by the Turgay Diagnostic and Statistical Manual of Mental Disorders 4th Edition - Disruptive Behaviour Disorders Rating Scale and Wechsler Intelligence Scale for Children Revised, respectively. Patients with a diagnosis of BECTS were divided into 2 groups: children with a behavioral disorder and children without a behavioral disorder. Demographic characteristics, clinical and electroencephalography (EEG) findings, and intelligence level were compared between the two groups. RESULTS: Twelve of the patients (29%) were classified as having attention-deficit/hyperactivity disorder (ADHD) and 2 (5%) were classified as having oppositional defiant disorder (ODD). The age at seizure onset was earlier in patients with behavioral disorders (p = 0.023). Bilateral interictal epileptic discharges (IEDs) were more common in children with behavioral disorders than children without behavioral disorders (p = 0.039). The most preferred antiseizure medication was carbamazepine, followed by levetiracetam and valproic acid. The intelligence score of the patients with BECTS was in the normal range in both groups. The total, verbal, and performance scores were lower in patients with a behavioral disorder than in patients without a behavioral disorder, but there was no statistically significant difference between the two groups. CONCLUSION: Behavioral disorders may be present in approximately one-third of patients with BECTS. Early onset of seizures and the presence of bilateral IEDs may be risk factors for behavioral disorders in children with BECTS.

Biallelic Variants in OTUD6B Cause an Intellectual Disability Syndrome Associated with Seizures and Dysmorphic Features.

Ubiquitination is a posttranslational modification that regulates many cellular processes including protein degradation, intracellular trafficking, cell signaling, and protein-protein interactions. Deubiquitinating enzymes (DUBs), which reverse the process of ubiquitination, are important regulators of the ubiquitin system. OTUD6B encodes a member of the ovarian tumor domain (OTU)-containing subfamily of deubiquitinating enzymes. Herein, we report biallelic pathogenic variants in OTUD6B in 12 individuals from 6 independent families with an intellectual disability syndrome associated with seizures and dysmorphic features. In subjects with predicted loss-of-function alleles, additional features include global developmental delay, microcephaly, absent speech, hypotonia, growth retardation with prenatal onset, feeding difficulties, structural brain abnormalities, congenital malformations including congenital heart disease, and musculoskeletal features. Homozygous Otud6b knockout mice were subviable, smaller in size, and had congenital heart defects, consistent with the severity of loss-of-function variants in humans. Analysis of peripheral blood mononuclear cells from an affected subject showed reduced incorporation of 19S subunits into 26S proteasomes, decreased chymotrypsin-like activity, and accumulation of ubiquitin-protein conjugates. Our findings suggest a role for OTUD6B in proteasome function, establish that defective OTUD6B function underlies a multisystemic human disorder, and provide additional evidence for the emerging relationship between the ubiquitin system and human disease.

Monogenic lupus due to spondyloenchondrodysplasia with spastic paraparesis and intracranial calcification: case-based review.

Spondyloenchondrodysplasia (SPENCD) is a rare skeletal dysplasia characterized with platyspondyly and metaphyseal lesions of the long bones mimicking enchondromatosis, resulting in short stature. SPENCD often coexists with neurologic disorders and immune dysregulation. Spasticity, developmental delay and intracranial calcification are main neurologic abnormalities. Large spectrum of immunologic abnormalities may be seen in SPENCD, including immune deficiencies and autoimmune disorders with autoimmune thrombocytopenia and systemic lupus erythematosus as the most common phenotypes. SPENCD is caused by loss of tartrate-resistant acid phosphatase (TRAP) activity, due to homozygous mutations in ACP5, playing a role in non-nucleic acid-related stimulation/regulation of the type I interferon pathway. We present two siblings, 13-year-old girl and 25-year-old boy with SPENCD, from consanguineous parents. Both patients had short stature, platyspondyly, metaphyseal changes, spastic paraparesis, mild intellectual disability, and juvenile-onset SLE. The age at disease-onset was 2 years for girl and 19 years for boy. Both had skin and mucosa involvement. The age at diagnosis of SLE was 4 years for girl, and 19 years for boy. The clinical diagnosis of SPENCD was confirmed by sequencing of ACP5 gene, which revealed a homozygous c.155A > C (p.K52T), a variant reported before as pathogenic. Juvenile-onset SLE accounts for about 15-20% of all SLE cases. But, the onset of SLE before 5-years of age and also monogenic SLE are rare. Our case report and the literature review show the importance of multisystemic evaluation in the diagnosis of SPENCD and to remind the necessity of investigating the monogenic etiology in early-onset and familial SLE cases.

FAM160B1 deficit associated with microcephaly, severe intellectual disability, ataxia, behavioral abnormalities and speech problems.

Intellectual disability (ID) varies in severity and is often associated with a variety of other clinical features. In consanguineous populations ID is usually inherited in an autosomal recessive fashion. Many genes are known for the condition, but many more are yet to be identified. By linkage analysis and exome sequencing we identified homozygous early truncating variant c.115G > T (p.Glu39*) in FAM160B1 in a 38-year-old woman with severe ID, microcephaly, behavioral abnormalities, speech problems, mild ataxia and mild facial dysmorphism. Recently homozygous missense c.248 T > C (p.Leu83Pro) was reported to underlie the ID syndrome in a 7-year-old boy and his two younger siblings. Some findings for those siblings overlap with those for our patient, but our patient does not have cutis laxa. Our findings confirm FAM160B1, with unknown function, as a syndromic ID gene and indicate that FAM160B1 is not essential for survival but is vital for proper functioning of the nervous system, delineate the FAM160B1-related ID, and describe the disease in a much older age.

Neonatal sepsis and simple minor neurological dysfunction.

BACKGROUND: This study examined potential risk factors for and consequences of simple minor neurological dysfunction (SMND), in a group of very low-birthweight newborns followed until preschool age. METHODS: This was a prospective longitudinal study. Children with birthweight <1500 g were assessed at 4-6 years of age. Twenty-eight children with normal neurological examination and 35 children with SMND were included in the final analysis. Risk factors for the development of SMND and its association with certain neuropsychiatric conditions were studied. RESULTS: Based on neonatal data, in children with SMND, Apgar score at 1 min (6.13 ± 2.37 vs 7.66 ± 1.04, P = 0.008) and at 5 min (8.63 ± 1.29 vs 9.45 ± 0.65, P = 0.019) was lower, duration of hospital stay was longer (45.8 ± 21.8 vs 35.1 ± 18.2 days, P = 0.037), and the frequency of sepsis was higher (73.5 vs 25%, P < 0.001). Sepsis was found to be an independent risk factor for SMND (OR, 7.6; 95% CI: 2.2-26.0; P = 0.001). The children with SMND had lower intelligence quotient and higher prevalence of hyperactivity and refraction error. CONCLUSION: Postnatal sepsis was the single most important risk factor for the development of SMND, and these children with SMND are at great risk for certain neuropsychiatric conditions. Preventive strategies, particularly for sepsis in the neonatal period, and early diagnosis and rehabilitation of future neuropsychiatric disorders are needed for better management of these cases.

New hyperekplexia mutations provide insight into glycine receptor assembly, trafficking, and activation mechanisms.

Hyperekplexia is a syndrome of readily provoked startle responses, alongside episodic and generalized hypertonia, that presents within the first month of life. Inhibitory glycine receptors are pentameric ligand-gated ion channels with a definitive and clinically well stratified linkage to hyperekplexia. Most hyperekplexia cases are caused by mutations in the α1 subunit of the human glycine receptor (hGlyR) gene (GLRA1). Here we analyzed 68 new unrelated hyperekplexia probands for GLRA1 mutations and identified 19 mutations, of which 9 were novel. Electrophysiological analysis demonstrated that the dominant mutations p.Q226E, p.V280M, and p.R414H induced spontaneous channel activity, indicating that this is a recurring mechanism in hGlyR pathophysiology. p.Q226E, at the top of TM1, most likely induced tonic activation via an enhanced electrostatic attraction to p.R271 at the top of TM2, suggesting a structural mechanism for channel activation. Receptors incorporating p.P230S (which is heterozygous with p.R65W) desensitized much faster than wild type receptors and represent a new TM1 site capable of modulating desensitization. The recessive mutations p.R72C, p.R218W, p.L291P, p.D388A, and p.E375X precluded cell surface expression unless co-expressed with α1 wild type subunits. The recessive p.E375X mutation resulted in subunit truncation upstream of the TM4 domain. Surprisingly, on the basis of three independent assays, we were able to infer that p.E375X truncated subunits are incorporated into functional hGlyRs together with unmutated α1 or α1 plus ß subunits. These aberrant receptors exhibit significantly reduced glycine sensitivity. To our knowledge, this is the first suggestion that subunits lacking TM4 domains might be incorporated into functional pentameric ligand-gated ion channel receptors.

Adult phenotype and further phenotypic variability in SRD5A3-CDG.

BACKGROUND: SRD5A3 is responsible for SRD5A3-CDG, a type of congenital disorder of glycosylation, and mutations have been reported in 15 children. All the mutations are recessive and truncating. CASE PRESENTATION: We present 2 brothers at the age of 38 and 40 years with an initial diagnosis of cerebellar ataxia. We found the candidate disease loci via linkage analysis using data from single nucleotide polymorphism genome scans and homozygous truncating mutation SRD5A3 p.W19X, which was previously reported in 3 unrelated children, by exome sequencing.Clinical investigations included physical and ocular examinations and blood tests. Severe ocular involvement with retinal bone spicule pigmentation and optic atrophy are the most prominent disabling clinical features of the disease. The serum transferrin isoelectric focusing (TIEF) pattern is abnormal in the patient investigated. CONCLUSION: Our patients are older, with later onset and milder clinical phenotypes than all patients with SRD5A3-CDG reported so far. They also have atypical ocular findings and variable phenotypes. Our findings widen the spectrum of phenotypes resulting from SRD5A3 mutations and the clinical variability of SRD5A3-CDG, and suggest screening for SRD5A3 mutations in new patients with at least a few of the clinical symptoms of SRD5A3-CDG.

Compound Heterozygous ROBO3 Mutation in Two Siblings Presenting with Horizontal Gaze Palsy without Scoliosis: Case-Based Review.

Horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare, autosomal recessively inherited disorder characterized by a congenital absence of conjugated horizontal eye movements with progressive scoliosis developing in childhood and adolescence. HGPPS is caused by mutations of the ROBO3 gene that disrupts the midline crossing of the descending corticospinal and ascending lemniscal sensory tracts in the medulla. We present two siblings, 5-year-old and 2-year-old boys with HGPPS, from non-consanguineous parents. The older brother was brought for the evaluation of moderate psychomotor retardation. He had bilateral horizontal gaze palsy with preserved vertical gaze and convergence. Scoliosis was absent. Cranial MRI showed brainstem abnormalities, and diffusion tensor imaging showed absent decussation of cortico-spinal tracts in the medulla. Clinical diagnosis of HGPPS was confirmed by sequencing of ROBO3 gene, IVS4-1G > A (c.767-1G > A) and c.328_329delinsCCC (p.Asp110Profs*57) compound heterozygous variations were found, and segregated in parents. The younger boy was first reported at 16 months of age and had the same clinical and neuroradiological findings, unlike mild psychomotor retardation. ROBO3 gene analysis showed the same variants in his brother. Our cases show the importance of evaluating eye movements in children with neurodevelopmental abnormalities and looking for brainstem abnormalities in children with bilateral horizontal gaze palsy.

Retinal and Choroidal Vascularity Evaluation in Pediatric Radiologically Isolated Syndrome and Multiple Sclerosis.

BACKGROUND: To assess vessel density (VD) and flow of retinal plexuses and peripapillary region related with the pediatric radiologically isolated syndrome (RIS) and multiple sclerosis (MS). METHODS: We analyzed 24 eyes of 12 participants with the diagnosis of RIS, 24 eyes of 12 participants with the diagnosis of MS, and 26 eyes of 13 age- and sex-matched healthy controls in this prospective, cross-sectional study. The superficial capillary plexus (SCP) and deep capillary plexus, foveal avascular zone, and the flow of choriocapillaris were investigated using optical coherence tomography angiography. RESULTS: Parafoveal VD and all subregion parameters in SCP were significantly decreased in the MS group compared with the controls, whereas only nasal and inferior VD were significantly decreased in the pediatric RIS group compared with the controls. Ganglion cell layer (GCL) thickness of all subregions of the inner ring was significantly decreased in the pediatric MS group compared with the control group. No significant difference was observed between the pediatric RIS group and the control group regarding thickness. CONCLUSIONS: We showed lower parafoveal VD in all subregions of SCP in pediatric MS, whereas only parafoveal nasal and inferior VD were decreased in pediatric RIS. GCL thickness of inner ring was significantly decreased in the pediatric MS, whereas GCL thickness did not change in pediatric RIS. Therefore, a decrease of parafoveal nasal and inferior VD without a decrease in thickness implies an early impairment of microvasculature in the RIS before impairment of thickness and that microvascular alterations begin from highly vascular superficial parafovea.

Autoimmune Hemolytic Anemia Due to Spondyloenchondrodysplasia with Spastic Paraparesis and Intracranial Calcification due to Mutation in ACP5.

Spondyloenchondrodysplasia (SPENCD) is a rare spondylometaphyseal skeletal dysplasia with characteristic lesions mimicking enchondromatosis and resulting in short stature. A large spectrum of immunologic abnormalities may be seen in SPENCD, including immune deficiencies and autoimmune disorders. SPENCD is caused by loss of tartrate-resistant acid phosphatase activity, due to homozygous mutations in ACP5 , playing a role in nonnucleic-acid-related stimulation/regulation of the type I interferon pathway. In this article, we presented a 19-year-old boy with SPENCD, presenting with recurrent autoimmune hemolytic anemia episodes since he was 5 years old. He had short stature, platyspondyly, metaphyseal changes, intracranial calcification, spastic paraparesis, and mild intellectual disability. He also had recurrent pneumonia attacks. The clinical diagnosis of SPENCD was confirmed by sequencing of the ACP5 gene, and a homozygous c.155A > C (p.K52T) variation was found, which was reported before as pathogenic. In conclusion, in early onset chronic autoimmune cytopenias an immune dysregulation may often have a role in the etiology. Associating findings and immunologic functions should be carefully evaluated in such patients in the light of the literature. The present case shows the importance of multisystemic evaluation for the detection of SPENCD that has a monogenic etiology.

Evaluation of mental performance and cognitive functions of children and adolescents diagnosed with radiologically isolated syndrome.

BACKGROUND: Radiologically isolated syndrome (RIS) is a condition characterized by asymptomatic, incidentally detected demyelinating plaques in the CNS in a patient without typical clinical findings of multiple sclerosis (MS). This study aimed to compare the mental status and cognitive functions of child and adolescent RIS cases with healthy controls and to investigate the relationship between psychometric test results and the demyelinating lesion characteristics. METHODS: The mental status and cognitive functions of 12 RIS cases and 12 healthy controls were compared. Semi-structured interviews, behavioral evaluations, depression and anxiety scales, neuropsychological test battery, and an intelligence test were applied for the evaluation of mental state and cognitive functions. These results were compared with the number and localization of demyelinating lesions. RESULTS: Sustained attention, visual-motor coordination, short-term memory skills, and ability to use visual-spatial information were found worse in the RIS group. There was no correlation between mental state and cognitive functions, and the number and localization of demyelinating lesions. CONCLUSION: Our study showed that pediatric RIS cases may have worse cognitive performance than healthy controls, but no correlation was found between the number and location of demyelinating lesions and psychiatric findings. Although it is controversial whether psychiatric disorders and cognitive disabilities have predictive value in terms of MS conversion in pediatric RIS cases, these subjects were not included in the scope of this study.

A Retrospective Review of 18 Patients With Childhood-Onset Hereditary Spastic Paraplegia, Nine With Novel Variants.

BACKGROUND: Hereditary spastic paraplegias (HSPs) are a group of genetically heterogeneous neurodegenerative disorders. Our objective was to determine the clinical and molecular characteristics of patients with genetically confirmed childhood-onset HSPs and to expand the genetic spectrum for some rare subtypes of HSP. METHODS: We reviewed the charts of subjects with genetically confirmed childhood-onset HSP. The age at the disease onset was defined as the point at which the delayed motor milestones were observed. Delayed motor milestones were defined as being unable to hold the head up by four months, sitting unassisted by nine months, and walking independently by 17 months. If there were no delayed motor milestones, age at disease onset was determined by leg stiffness, frequent falls, or unsteady gait. Genetic testing was performed based on delayed motor milestones, progressive leg spasticity, and gait difficulty. The variant classification was determined based on the American College of Medical Genetics standard guidelines for variant interpretation. Variants of uncertain significance (VUS) were considered disease-associated when clinical findings were consistent with the previously described disease phenotypes for pathogenic variants. In addition, in the absence of another pathogenic, likely pathogenic, or VUS variant that could explain the phenotype of our cases, we concluded that the disease is associated with VUS in the HSP-causing gene. Segregation analysis was also performed on the parents of some patients to demonstrate the inheritance model. RESULTS: There were a total of 18 patients from 17 families. The median age of symptom onset was 18 months (2 to 84 months). The mean delay between symptom onset and genetic diagnosis was 5.8 years (5 months to 17 years). All patients had gait difficulty caused by progressive leg spasticity and weakness. Independent walking was not achieved at 17 months for 67% of patients (n = 12). In our cohort, there were two subjects each with SPG11, SPG46, and SPG 50 followed by single subject each with SPG3A, SPG4, SPG7, SPG8, SPG30, SPG35, SPG43, SPG44, SPG57, SPG62, infantile-onset ascending spastic paralysis (IAHSP), and spastic paraplegia and psychomotor retardation with or without seizures (SPPRS). Eight novel variants in nine patients were described. Two affected siblings had a novel variant in the GBA2 gene (SPG46), and one subject each had a novel variant in WASHC5 (SPG8), SPG11 (SPG11), KIF1A (SPG30), GJC2 (SPG44), ERLIN1 (SPG62), ALS2 (IAHSP), and HACE1 (SPPRS). Among the novel variants, the variant in the SPG11 was pathogenic and the variants in the KIF1A, GJC2, and HACE1 were likely pathogenic. The variants in the GBA2, ALS2, ERLIN1, and WASHC5 were classified as VUS. CONCLUSIONS: There was a significant delay between symptom onset and genetic diagnosis of HSP. An early diagnosis may be possible by examining patients with delayed motor milestones, progressive spasticity, gait difficulties, and neuromuscular weakness in the context of HSP. Eight novel variants in nine patients were described, clinically similar to the previously described disease phenotype associated with pathogenic variants. This study contributes to expanding the genetic spectrum of some rare subtypes of HSP.

Optic neuritis in Turkish children and adolescents: A multicenter retrospective study.

BACKGROUND: Various etiologies may underlie optic neuritis, including autoantibody-mediated disorders described in the last decade. We re-examined demographic, clinical, laboratory features and prognostic factors in pediatric patients with autoimmune optic neuritis according to current knowledge. METHODS: Cases of pediatric ON from 27 centers in Türkiye diagnosed between 2009 and 2022 were included for retrospective evaluation. RESULTS: The study included 279 patients, 174 females and 105 males, with a female-to-male ratio of 1.65. The average age at onset was 12.8 ± 3.4 years, and mean follow-up, 2.1 years (range: 1-12.1 years). Patients <10 years old were grouped as "prepubertal" and those ≥10 years old as "others". The diagnoses made at the end of follow-up were multiple sclerosis associated optic neuritis (n = 90, 32.3 %), single isolated optic neuritis (n = 86, 31 %), clinically isolated syndrome (n = 41, 14.7 %), myelin oligodendrocyte glycoprotein antibody associated optic neuritis (n = 22, 7.9 %), and relapsing isolated optic neuritis (n = 18, 6.5 %). Predominant diagnoses were myelin oligodendrocyte glycoprotein antibody associated optic neuritis and acute disseminated encephalomyelitis associated optic neuritis in the prepubertal group and multiple sclerosis associated optic neuritis in the older group. Recurrences were observed in 67 (24 %) patients, including 28 with multiple sclerosis associated optic neuritis, 18 with relapsing isolated optic neuritis, 11 with myelin oligodendrocyte glycoprotein antibody associated optic neuritis, 8 with aquaporin-4 antibody related optic neuritis, and 2 with chronic relapsing inflammatory optic neuropathy. Recurrences were more common among female patients. Findings supporting the diagnosis of multiple sclerosis included age of onset ≥ 10 years (OR=1.24, p = 0.027), the presence of cranial MRI lesions (OR=26.92, p<0.001), and oligoclonal bands (OR=9.7, p = 0.001). Treatment in the acute phase consisted of intravenous pulse methylprednisolone (n = 46, 16.5 %), pulse methylprednisolone with an oral taper (n = 212, 76 %), and combinations of pulse methylprednisolone, plasmapheresis, or intravenous immunoglobulin (n = 21, 7.5 %). Outcome at 12 months was satisfactory, with 247 out of 279 patients (88.5 %) demonstrating complete recovery. Thirty-two patients exhibited incomplete recovery and further combination treatments were applied. Specifically, patients with relapsing isolated optic neuritis and aquaporin-4 antibody related optic neuritis displayed a less favorable prognosis. CONCLUSION: Our results suggest optic neuritis is frequently bilateral in prepubertal and unilateral in peri­ or postpubertal patients. Age of onset 10 or older, presence of oligoclonal bands, and brain MRI findings reliably predict the development of multiple sclerosis. The risk of developing multiple sclerosis increases mostly during the second and third years of follow-up. Relapsing isolated optic neuritis remains a separate group where the pathogenesis and outcome remain unclear. Investigation of predisposing and diagnostic biomarkers and long follow-up could help to define this group.

A frameshift mutation of ERLIN2 in recessive intellectual disability, motor dysfunction and multiple joint contractures.

We present a family afflicted with a novel autosomal recessive disease characterized by progressive intellectual disability, motor dysfunction and multiple joint contractures. No pathology was found by cranial imaging, electromyography and muscle biopsy, but electron microscopy in leukocytes revealed large vacuoles containing flocculent material. We mapped the disease gene by SNP genome scan and linkage analysis to an ∼0.80 cM and 1 Mb region at 8p11.23 with a multipoint logarithm of odds (LOD) score of 12. By candidate gene approach, we identified a homozygous two-nucleotide insertion in ERLIN2, predicted to lead to the truncation of the protein by about 20%. The gene encodes endoplasmic reticulum (ER) lipid raft-associated protein 2 that mediates the ER-associated degradation of activated inositol 1,4,5-trisphosphate receptors and other substrates.

Fine motor skills in children with rolandic epilepsy.

This study aimed to evaluate fine motor skills in children with rolandic epilepsy (RE). The research included 44 children diagnosed with typical RE and 44 controls matched in terms of age, gender, and level of education. Fine motor skills were evaluated with the Purdue Pegboard Test, and intelligence was measured with the Wechsler Intelligence Scale for Children. After controlling for the effect of intelligence on fine motor skills, the results showed that the children with RE did not perform as well as the controls in the PPT dominant hand, both hands, and assembly subtests. Epileptic focus, treatment status, type of antiepileptic treatment, age at the time of the first seizure, time since the last seizure, and total number of seizures did not affect motor skills. Rolandic epilepsy negatively affected fine motor skills regardless of the children's level of intelligence.

Mild hemolytic anemia, progressive neuromotor retardation and fatal outcome: a disorder of glycolysis, triose- phosphate isomerase deficiency.

A two-month-old male infant presented with jaundice, pallor, and hepatomegaly. The first child of non-consanguineous parents had also suffered from hemolytic anemia and neuromotor retardation and died at the age of 21 months. The patient required phototherapy and transfusion in the newborn period but hemolysis was mild thereafter. The patient had neuromotor retardation, and at the age of 14 months, ventilatory support was necessary, and the patient lived until 17 months. Triose-phosphate isomerase (TPI) deficiency, which is a rare autosomal recessive multisystem disorder of glycolysis, was detected. There was homozygous missense mutation in the TPI1 gene (p.Glu105Asp). This is the most common mutation with a severe phenotype that requires ventilator support in the second year of life. In patients with hemolysis and neuromotor retardation, TPI deficiency must be considered. There is no specific treatment, but detection of the index case may provide the opportunity for genetic counseling and prenatal diagnosis.