Objective:To investigate the clinical phenotype and genetic characteristics of developmental epileptic encephalopathy 18 (DEE18) caused by SZT2 gene variants. Methods:Clinical data of 2 children with SZT2 related DEE18 who visited the Department of Pediatric Neurology, Linyi People′s Hospital in March 2020 and July 2023 were collected. The whole exome sequencing (WES) and Sanger sequencing were applied to verify the child and their parents. SWISS-MODEL software was used to perform protein 3D modeling for the selected SZT2 gene variants. Results:Both of the 2 cases showed severe global developmental delay, epileptic seizures, autism, megacephaly, facial deformity, hypotonia, corpus callosum malformation, persistent cavum septum pellucidum, and slow background activity and focal discharge in video electroencephalography. Case 1 was easy to startle and thin in stature; case 2 had immune deficiency and clustered seizures. WES results showed that case 1 carried a compound heterozygous variant of c.5811G>A (p.W1937X) (paternal) and c.9269delG (p.S3090Ifs *94) (maternal), while case 2 carried a compound heterozygous variant of c.6302A>C(p.H2101P) (paternal) and c.7584dupA (p.E2529Rfs *20) (maternal), the parents of both patients with normal clinical phenotypes. The 4 mutations mentioned above were novel variations that had not yet been reported domestically or internationally. According to the American College of Medical Genetics and Genomics variant classification criteria and guidelines, the p.S3090Ifs *94 variant was interpreted as pathogenic; p.W1937X variant was interpreted as pathogenic; p.E2529Rfs *20 variant was interpreted as likely pathogenic; p.H2101P variant was interpreted as uncertain significance. 3D modeling showed that the variant of p.H2101P resulted in a significant change in the hydrogen bond around the 2 101st amino acid encoded, leading to a decrease in protein stability. The other 3 variants led to early truncation of peptide chain and obvious changes in protein structure. Conclusions:DEE18 caused by SZT2 gene mutation is mainly an autosome recessive genetic disease, and its clinical manifestations include global developmental delay, epileptic seizures, autism, craniofacial malformation, hypotonia, epileptic discharge, corpus callosum malformation, persistent cavum septum pellucidum, shock, small and thin stature, and immune deficiency. Four novel variants related to the SZT2 gene may be the genetic etiology of DEE18 patients in this study.

Objective:To investigate the clinical phenotype and genetic characteristics of infantile epileptic spasm syndrome caused by BRWD3 gene mutation. Methods:Clinical data of a child with BRWD3 related infantile epileptic spasm syndrome who was admitted to Department of Pediatric Neurology of Linyi People′s Hospital on August 2, 2019 were collected and followed up, whole exome sequencing technology and Sanger sequencing were applied to verify the child and his parents, and the pathogenicity of mutation site was analyzed. The studies till June 2023 were searched with keywords of " BRWD3" in both English and Chinese databases of China National Knowledge Infrastructure, Wanfang, Online Mendelian Inheritance in Man, and PubMed. The clinical phenotype and genetic characteristics of patients with BRWD3 related epilepsy were summarized. Results:The patient was a 4 years and 4 months old boy, with a clinical phenotype including severe global development delay, focal seizures (the onset age was 4 months), epileptic spasm (the onset age was 6 months), autism, megacephaly, high forehead as well as hypsarrhythmia. The whole exome sequencing results showed a de novo and frameshift variation c.4318_4319del(p.Q1441Efs*20)(NM_153252) in the BRWD3 gene, and the variation was interpreted as pathogenic (PVS1+PS2+PM2) according to the American College of Medical Genetics and Genomics variant classification criteria and guidelines. A total of 7 English literature articles were retrieved reporting 16 cases of BRWD3 gene related epilepsy in children (including 1 case of infantile epileptic spasm syndrome), and there has been no report in China yet. Totally there were 17 cases of BRWD3 gene related epilepsy including this case. All the cases showed X chromosome dominant inheritance, of whom 15 cases showed minor variations, including 7 missense variations, 3 frameshift variations, 3 splicing variations, 2 nonsense variations, and the remaining 2 cases showed large segment deletions. A total of 15 different variants were found. The phenotypes of the 17 patients mainly included epileptic seizures (17/17), intellectual disability (10/17), motor development disorder (7/17), speech impairment (9/17), megacephaly (8/17), facial malformation (8/17), autism (4/17) and hypotonia (4/17). The common seizure types were found to be focal seizures, occasionally epileptic spasm seizures and tonic seizures. Conclusions:BRWD3 gene variation related epilepsy is an X chromosome dominant genetic disease with a wide clinical phenotype spectrum. BRWD3 gene mutation c.4318_4319del(p.Q1441Efs *20) could cause infantile epileptic spasm syndrome, manifested as severe global developmental delay, epileptic spasm, focal seizures, autism, craniofacial malformation and hypsarrhythmia. This research enriches BRWD3 gene mutation spectrum.

Objective:To analyze the clinical phenotypes and TSC1/TSC2 gene variations in 52 children with tuberous sclerosis complex. Methods:The clinical data of 59 children with tuberous sclerosis complex hospitalized in Linyi People′s Hospital between January 2017 and October 2022 were collected. The analysis of TSC1 and TSC2 gene variations on main family members was performed, and then bioinformatics analysis followed. The positive children were divided into TSC1 gene group and TSC2 gene group, and the difference of clinical characteristics between the two groups was analyzed. Results:Among 59 children, 52 cases were detected TSC1/ TSC2 gene variations (17 cases in the TSC1 gene group and 35 cases in the TSC2 gene group). Of the 52 children, 28 (53.8%) were male, 24 were female (46.2%); 17 (32.7%) were familial cases (10 with TSC1 gene variations and 7 with TSC2 gene variations), 35 (67.3%) were sporadic cases; 46 (88.5%) had hypomelanotic macules, 13 (25.0%) had facial angiofibromas, 5 (9.6%) had shagreen patches, 49 (94.2%) had subependymal nodules/calcifications, 47 (90.4%) had cortical nodules, 2 (3.8%) had subependymal giant cell astrocytomas, 39 (75.0%) had intellectual/developmental disabilities, 49 (94.2%) had epileptic seizures, 8 (15.4%) had cardiac rhabdomyomas, 9 (17.3%) had renal angiomyolipomas, and 4 (7.7%) had retinal hamartomas. Of the 52 children, 49 variations were detected, including 4 large fragment deletion/duplication variations, and 45 point variations; 41 pathogenic variations, 7 likely pathogenic variations, and 1 variation of uncertain significance. In this study, 16 point mutations and 1 large fragment duplication mutation which had not been reported at home and abroad, and 3 high-frequency mutation sites (p.Arg692 *, p.Arg228 *, and p.Arg1200Try) were found. There was a statistically significant difference in the proportion of familial cases [10/17 vs 7/35(20%), χ2=7.838, P=0.005], median onset age of epilepsy [38.0(0.5-134.0) months vs 8.0(0.1-63.0) months, Z=3.506 , P<0.001] and the incidence of developmental retardation/intellectual impairment [8/17 vs 31/35(88.6%), χadj2=8.423, P=0.004] between the TSC1 gene and TSC2 gene groups. Conclusions:Tuberous sclerosis compiex has widespread phenotypes, can affect every body system, especially the skin and nervous system. The pathogenic gene is TSC1/ TSC2. The TSC1 gene group has more familial cases. The TSC2 gene group has an earlier onset age of epilepsy and a higher incidence of developmental retardation/intellectual impairment. In this study, 16 novel point mutations, 1 novel large fragment duplication mutation, and 3 hotspot mutations were identified, expanding the gene variation spectrum of tuberous sclerosis complex.

Objective To explore the oral mucosal manifestations of Sweet's syndrome and provide a reference for its early detection and correct diagnosis.Methods The oral mucosal manifestations of a 60-year-old female patient with Sweet's syndrome are described in detail,followed by a discussion of the related literature.Results The patient had skin erythema of both lower extremities,which was accompanied by oral mucosal ulceration and pain for 3 days.The patient presented with mild cutaneous lesions and diffuse large-scale erosion in the oral mucosa with obvious pain.During the onset of the disease,the patient was accompanied by fever with a temperature of 38.5℃.After visiting the Department of Stomatology,laboratory tests showed an increase in C-reactive protein(35.2 mg/L)and an accelerated erythrocyte sedimentation rate(77.00 mm/h).Scattered red plaques and mild tenderness were observed in the knees and lower limbs.Histopathological examination of the skin lesions revealed scattered infiltration of immature neutrophils across the entire dermis.The patient responded well to glucocorticoid therapy.According to the clinical signs and labo-ratory examination,combined with the lesion histopathological results,a diagnosis of Sweet's syndrome was given.The patient was administered 1 mL compound Betamethasone injection only once intramuscularly.In the meantime,the pa-tient was asked to gargle with compound chlorhexidine solution and topically apply recombinant bovine basic fibroblast growth factor solution to the damaged mucosa three times a day for 1 week.After 4 days of medication,the patient's body temperature had returned to normal and the oral lesions were significantly reduced.After 2 weeks,the erythema in the leg and knee had almost all subsided,and the oral mucosal lesions had disappeared.The patient was followed up 6 months after treatment,with no recurrence of skin lesions.After 2 years of follow-up,the disease was stable with no re-currence.A review of the relevant literature shows that Sweet's syndrome is a rare inflammatory reactive dermatosis with unknown etiology,which can be divided into three clinical types:specific,tumor-related,and drug-induced.The male/female prevalence ratio is 1:4.The salient clinical manifestations are abrupt onset of painful erythematous plaques or nodules most commonly involving the extremities,often accompanied by pyrexia,elevated neutrophil count,elevation of the erythrocyte sedimentation rate,and positive C-reactive protein.The use of glucocorticoids is the most common treatment for this disease,and most patients see a rapid improvement in skin lesions;however,some may experience infection or recurrence after withdrawal.Some patients with Sweet's syndrome are accompanied by oral lesions,but cases of oral mucosal damage have been rarely reported,and this condition is easily misdiagnosed.Conclusion Oral mucosal lesions may be extraterritorial manifestations of Sweet's syndrome,and the patient's systemic condition should be comprehensively considered.Skin biopsy should be completed as soon as possible to make a clear diagnosis,so as not to delay the disease.J Prev Treat Stomatol Dis,2024,32(8):620-624.

Objective:To explore the clinical and genetic characteristics of five children with epilepsies due to variants of SCN8A gene. Methods:Clinical data of five children (four males and one female) admitted to Linyi People′s Hospital due to hereditary epilepsies between August 2015 and August 2022 were collected. Whole exome sequencing was carried out for these children, and candidate variants were verified by Sanger sequencing.Results:All of the five children were found to harbor variants of the SCN8A gene. Case 1, who had benign familial infantile epilepsy, inherited a known pathogenic c. 4840A>G variant from his father with similar symptoms. Cases 2 to 4 had presented with intermediate epilepsy. Among these, case 2 has harbored a de novo c. 3967G>A variant which was rated as pathogenic (PS1+ PS2+ PM1+ PM2_Supporting+ PP3) based on the guidelines from the American College of Medical Genetics and Genomics. Cases 3 and 4 were found to respectively harbor a de novo c. 415A>T and a c. 4697C>T variant, which were both rated as likely pathogenic (PS2+ PM1+ PM2_Supporting+ PP3). Case 5, who had early-onset infantile epileptic encephalopathy transformed into Lennox Gastaut-like syndrome, has harbored a de novo c. 5615G>A variant, which was known to be pathogenic. The children had their age of onset ranging from 2 to 14 months, and all had focal seizures and generalized tonic clonic seizures. Four children (cases 1, 2, 3 and 5) had cluster seizures, four (cases 1 to 4) had become seizure-free after single or dual treatment and showed normal growth and development, whilst case 5 was drug-resistant and showed severe developmental retardation. Conclusion:The five children had new features such as cluster seizures, occasional benign seizures in adulthood, and intermediate epilepsy which are prone to relapse after discontinuation of medication, which may be attributed to the pathogenic variants of the SCN8A gene.

Objective:To explore the clinical manifestations and pathogenic variant in a family with epilepsy, developmental delay and brain deformity.Methods:Clinical data of the child and his family members who had visited the Department of Pediatrics, Linyi People's Hospital on July 2, 2022 were collected. The child, his sister and parents were subjected to high-throughput sequencing, and the result was verified by Sanger sequencing.Results:The child was a 6-year-old boy with developmentally delay and had epileptic seizures with fever sensitivity for four years. Cranial imaging showed brain dysplasia, while the video electroencephalogram showed abnormal discharge. High-throughput sequencing showed the child has harbored a heterozygous c. 5G>T (p.Arg2Leu) variant of TUBB2A gene, which was unreported previously. His sister also carried the variant and had similar clinical manifestations, whilst his parents were of the wild-type and had normal clinical phenotypes. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as pathogenic (PS2+ PM2_Supporting+ PM5+ PP1+ PP2+ PP3). Conclusion:The heterozygous c. 5G>T (p.Arg2Leu) variant of the TUBB2A gene, in the form of gonadal mosaicism, probably underlay the disorders in this family.

Objective:To explore the clinical features and genetic etiology of a child with SPONASTRIME dysplasia (SD).Methods:A 9-month-old female who had presented at the Linyi People′s Hospital in August 2022 for short stature was selected as the study subject. Clinical data of the child were collected, and whole exome sequencing (WES) was carried out. Sanger sequencing was used for validating the candidate variants.Results:The child has manifested short stature, mid-face hypoplasia, joint laxity, internal knee rotation, irregularities in the metaphysis of long bones, and flat and concave lumbar vertebrae. WES revealed that she has harbored compound heterozygous variants of the TONSL gene, namely c.3088G>T (p.Glu1030*) and c. 3053G>A (p.Arg1018His), which were inherited from her phenotypically normal parents. Neither variant was reported previously. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c. 3088G>T variant was classified as likely pathogenic (PVS1+ PM2_Supporting), whilst the c. 3053G>A was classified as a variant of uncertain significance (PM2_Supporting+ PM3+ PP3). Conclusion:The c. 3088G>T and c. 3053G>A compound heterozygous variants of the TONSL gene probably underlay the pathogenesis in this patient. Above finding has facilitated the clinical diagnosis and genetic counseling for her family.

Objective:To explore the clinical phenotype and genetic characteristics of children with childhood absence epilepsy caused by KMT2E gene variants. Methods:The clinical data of 1 case of KMT2E gene variant-associated childhood absence epilepsy admitted to the Department of Pediatric Neurology of Linyi People′s Hospital in January 2023 were collected and followed up, and the child and her family were genetically examined by using whole-exome sequencing and Sanger sequencing, and the pathogenicity of mutation loci was analyzed. The Online Mendelian Inheritance in Man, Human Gene Mutation Database, PubMed database, China National Knowledge Infrastructure, and Wanfang database were consulted with the search term " KMT2E" to summarize the clinical phenotype and genetics of the children with epilepsy associated with KMT2E gene variant. Results:The child is a female, presented with typical absence seizures at the age of 3 years and 8 months, with normal development, video electroencephalogram showing widespread spikes and slow waves around 3 Hz accompanied by typical absence seizures. Seizures decreased after valproic acid was applied at full dosage, and were controlled after combination with lamotrigine. Her clinical diagnosis of childhood absence epilepsy was made. The results of whole-exome sequencing showed that the child had a de novo frameshift variant c.2404dup (p.Arg802Lysfs *8) in the KMT2E gene (NM_182931.3), which had not yet been reported domestically or internationally. The c.2404dup variant was interpreted as a pathogenic variant (PVS1+PS2_Supporting+PM2_Supporting) according to the American Society of Medical Genetics and Genomics variant classification criteria and guidelines. Her parents, older brother and younger sister did not carry the variant and had a normal clinical phenotype. A total of 22 patients with epilepsy associated with KMT2E gene variants were retrieved (including this case, a total of 23 cases), including 10 females and 13 males. All of them were autosomal dominant inheritance, with 20 minor variations, including 8 frameshift variants, 7 missense variants, 2 splicing variants, 2 nonsense variants, 1 synonymous variant, and the remaining 3 cases had large fragment deletions (including 2 cases of the whole gene). Clinical manifestations mainly included epileptic seizures (5 cases of absence seizures, 7 cases of focal seizures with or without secondary tonic-clonic seizures, 9 cases of tonic-clonic seizures, 1 case of spasm seizures, 1 case of myoclonic seizures, tonic seizures, and atonic seizures, 3 cases of epileptic status, and 5 cases of refractory epilepsy, with the onset age of epilepsy ranging from neonatal to adolescence), mental retardation (21/23 cases, 4 mild, 5 moderate, and 5 severe), peculiar facial features (11/23), and autism (3/23), etc. Conclusion:KMT2E gene variant-associated epilepsy is an autosomal dominant disorder with a wide spectrum of clinical phenotypes, and the novel variant c.2404dup in the KMT2E gene identified in the present study can lead to childhood absence epilepsy, which enriches the spectrum of mutations and clinical phenotype of the KMT2E gene.

Objective:To investigate the clinical phenotype and genetic characteristics of a family with mitochondrial DNA depletion syndrome (MTDPS8B) caused by RRM2B gene mutation. Methods:Data of a family with MTDPS8B admitted to Department of Pediatric Neurology, Linyi People's Hospital in November 2019 were collected. Whole exome sequencing, mitochondrial loop gene sequencing and Sanger sequencing were used for genetic test in the child and family members, and pathogenicity analysis and protein 3D modeling on the mutation sites were conducted. The clinical phenotype and genetic characteristics of the family members were summarized.Results:Six subjects in these 8 individuals from the three generations of this family underwent genetic test. Four subjects had c.627G>A(p.M209I) (NM_001172477) heterozygous variation in RRM2B gene on the chromosome 8, and the variation was highly conserved; and no report on this variation has been found in domestic and foreign databases yet. Protein 3D modeling found that this variation may affect protein stability and function. The proband (male) and two older sisters carried the same variant had MTDPS8B, manifested as gastrointestinal dysfunction and progressive decline in motor function and intelligence, while the mother carried the same variant only had intellectual disability; the father and eldest sister did not carry the mutation and had normal clinical phenotype; the maternal grandparents had normal clinical phenotype and had passed away without genetic test; variation and disease were isolated in this family. The variation was interpreted as pathogenic (PM1+PM2+PP1+PP3) according to the American College of Medical Genetics and Genomics variant classification criteria and guidelines. Conclusion:The c.627G>A variant can cause RRM2B gene-related disease, and family members carried the same variants vary in clinical severity.

Objective:To summarize the clinical and genetic characteristics of children with epilepsy associated with SCN2A gene variations. Methods:A retrospective study was performed. Eleven children with epilepsy admitted to Department of Pediatric Neurology, Linyi People's Hospital from January 2017 to December 2022 were included; all of them had pathogenic SCN2A gene mutation. Genetic results and clinical data as epileptic seizure type/frequency, intelligence and motor development of these 11 children were collected. Epilepsy-related variations and pathogenesis of SCN2A gene were analyzed, and their correlations with clinical phenotypes in these children were analyzed. Results:Among the 11 patients, 6 had self-limited epilepsy (4 with variation in the intracellular domain and 2 in the transmembrane domain), 1 had febrile convulsion accompanied by childhood absent epilepsy (with variation in the intracellular domain), and 4 had developmental epileptic encephalopathy (2 with variation in the extracellular domain and 2 with variation in the transmembrane domain). SCN2A gene was missense mutation in these 11 children, and the mutation site in 6 children was not reported before. Various forms of video EEG discharge were noted, and 1 child with self-limited epilepsy showed transient multifocal epileptic discharge during frequent seizures. Oxcarbazepine and topiramate were effective for self-limiting epilepsy, and lamotrigine was effective in 1 child with late-onset epileptic encephalopathy. Eleven patients were followed up for (66±32) months; the age ranged from 8 months to 11 years and 6 months at the last follow-up; 10 patients had seizure remission and 1 had uncontrolled seizure. Conclusions:Besides self-limited epilepsy and developmental epileptic encephalopathy, SCN2A gene mutations are also associated with febrile convulsion and childhood absent epilepsy. Phenotypic differences are highly correlated with mutation locations; developmental epileptic encephalopathy associated variants are mostly located in extracellular domains, while self-limited epileptic variants are mostly located in intracellular domains.