Clinical, genetic characteristics and outcome of four Chinese patients with Bartter syndrome type 3: Further insight into a genotype-phenotype correlation.

Aim: To investigate the characteristics of 4 Chinese patients with Bartter syndrome type 3 (BS Type 3). Methods: The clinical data, genetic analysis, and outcome of four cases with Bartter syndrome type 3 were retrospectively summarised. Results: Gene sequencing analysis showed that all children carried a compound heterozygous mutation in the CLCNKB gene and were diagnosed with BS type 3. All types of mutations were detected, including two missense mutations, one nonsense mutation, one small fragment deletion mutation, two large deletion mutations and one splice-site mutation. The splice-site mutation c.100 + 1 (IVS2) C > T was novel. Two cases carried large deletion mutations. The patients presented as classic BS with modest manifestations. The most common sign was growth retardation. There was no polyhydramnios or preterm delivery. All cases were treated with potassium chloride supplementation and indomethacin. During long-term follow-up, clinical symptoms and growth retardation improved significantly. Nephrocalcinosis or renal dysfunction was not observed. Conclusion: The clinical manifestations of BS type 3 are mostly presented as cBS. Growth retardation is a common sign. BS type 3 had a good long-term prognosis. There were various types of mutations in the CLCNKB gene. Large deletions were the most common.

Influence of disease course and comprehensive management on blood glucose level in children and adolescents with type 2 diabetes mellitus.

AIMS/INTRODUCTION: The aim of the present study was to evaluate the status of glycemic control, and assess the effects of the disease course and comprehensive management measures on the blood glucose level in children and adolescents with type 2 diabetes mellitus. MATERIALS AND METHODS: The study collected the clinical data of type 2 diabetes patients in Beijing Children's Hospital from January 2015 to September 2020. Patients were grouped based on the disease course to compare their glycated hemoglobin (HbA1c) level, islet ß-cell function, insulin resistance and comprehensive management measures. RESULTS: Of the 170 participants, the median disease course was 2.0 years (interquartile range [IQR] 1.0-4.0 years). The baseline HbA1c was 11.2% (IQR 9.2-12.4%). According to the grouping by the disease course, the median HbA1c was the lowest (5.7% [IQR 5.3-6.1%]) in the half-year course group and the highest in the 4-year course group (9.0 [IQR 6.8%-11.3%]). Compared with the group with a disease duration <2 years, patients in the >4 years group had a lower proportion of patients with HbA1c <7% (29.2% vs 66.2%), a lower homeostasis model assessment of ß-cell function, and a lower proportion with a controlled diet, moderate-intensity exercise, regular follow up and no drug treatment. We deemed HbA1c as the dependent variable, and found that disease duration, homeostasis model assessment of ß-cell function at follow up, continuous moderate-intensity exercise, regular review and treatment regimen were significant influencing factors for glycemic control. CONCLUSIONS: Children and adolescents with type 2 diabetes and a prolonged disease course showed poor glycemic control and decreased islet ß-cell function. A good lifestyle, especially moderate-intensity exercise, can help such cases better control their blood glucose level.

Novel OBSL1 Variant in a Chinese Patient with 3M Syndrome and the c.458dupG Mutation May Be a Potential Hotspot Mutation in the Chinese Population.

3M syndrome is an autosomal recessive disorder characterized by short stature and skeletal developmental abnormalities. In this study, a Chinese patient with 3M syndrome was presented. A novel OBSL1 (obscurin-like 1 gene) variant was found. The patient is a 2-year-old girl who presented with short stature and had intrauterine growth retardation and low birth weight. Gene analysis revealed compound heterozygote mutations in the OBSL1 gene: c.458dupG (p.L154Pfs*100) and c.427dupG (p.A143Gfs*111). The c.427dupG mutation is novel. The c.458dupG mutation has been documented in 5 cases, occurring only in Chinese individuals, indicating ethnic specificity. In cases of short-statured children presenting intrauterine growth retardation, low birth weight, and skeletal developmental abnormalities, 3M syndrome should be considered. The c.458dupG mutation might be a hotspot mutation in the Chinese population.

A synonymous KCNJ11 variant leading to MODY13: A case report and literature review.

Background: Maturity-onset diabetes of the young, type 13 (MODY13) is a specific subclass of monogenic diabetes mellitus that does not exhibit the typical clinical manifestations of diabetes, necessitating the use of genetic testing for accurate diagnosis. With the progression of monogenic diabetes and MODY, the number of reported MODY13 cases has reached a minimum of 22. Nevertheless, there remains a dearth of information regarding patients diagnosed with MODY13 presenting synonymous variants. Case presentation: This study presents a description of the clinical and genetic features of a 9-year-old male patient diagnosed with MODY13. A noteworthy finding in this case was the occurrence of a "separation phenomenon" between C-peptide and insulin during the standard meal test. Whole exome sequencing (WES) identified a KCNJ11 c.843C > T (p.L281=) mutation in exon 1, which contradicted the previously reported phenotype. Following the onset of ketosis, the patient underwent insulin therapy for a duration of one month, during which the insulin dosage was gradually modified based on blood glucose levels. In order to maintain normoglycemia, he adhered to a diabetic dietary regimen and participated in 1-2 h of moderate exercise daily. Conclusion: The study implies that patient with KCNJ11 variant shows a "separation phenomenon" between C-peptide and insulin in standard meal test. Our report also enriched the genotype and phenotype spectrums of MODY13 and highlighted the importance of genetic testing in patients without characteristic clinical symptoms of diabetes.

Glutamate dehydrogenase hyperinsulinism: mechanisms, diagnosis, and treatment.

Congenital hyperinsulinism (CHI) is a genetically heterogeneous disease, in which intractable, persistent hypoglycemia is induced by excessive insulin secretion and increased serum insulin concentration. To date,15 genes have been found to be associated with the pathogenesis of CHI. Glutamate dehydrogenase hyperinsulinism (GDH-HI) is the second most common type of CHI and is caused by mutations in the glutamate dehydrogenase 1 gene. The objective of this review is to summarize the genetic mechanisms, diagnosis and treatment progress of GDH-HI. Early diagnosis and treatment are extremely important to prevent long-term neurological complications in children with GDH-HI.

Case report: Clinical manifestations and genotype analysis of a child with PTPN11 and SEC24D mutations.

Background: The PTPN11 gene, located at 12q24. 13, encodes protein tyrosine phosphatase 2C. Mutations in the PTPN11 gene can lead to various phenotypes, including Noonan syndrome and LEOPARD syndrome. The SEC24D gene is located at 4q26 and encodes a component of the COPII complex, and is closely related to endoplasmic reticulum protein transport. Mutations in SEC24D can lead to Cole-Carpenter syndrome-2. To date, dual mutations in these two genes have not been reported in the literature. Methods: We report a patient with short stature and osteogenesis imperfecta as the primary clinical manifestation. Other clinical features were peculiar facial features, deafness, and a history of recurrent fractures. Whole exome sequencing was performed on this patient. Results: After whole-exome sequencing, three mutations in two genes were identified that induced protein alterations associated with the patient's phenotype. One was a de novo variant c.1403C>T (p.Thr468Met) on exon 12 of the PTPN11 gene, and the other was a compound heterozygous mutation in the SEC24D gene, a novel variant c.2609_2610delGA (p.Arg870Thrfs*10) on exon 20 and a reported variant c.938G>A (p.Arg313His) on exon 8. Conclusions: Concurrent mutations in PTPN11 and SEC24D induced a phenotype that was significantly different from individual mutations in either PTPN11 or SEC24D gene. Personalized genetic analysis and interpretation could help us understand the patient's etiology and hence develop treatments and improve the prognosis of these patients.

Phosphomannomutase 2 hyperinsulinemia: Recent advances of genetic pathogenesis, diagnosis, and management.

Congenital hyperinsulinemia (CHI), is a clinically heterogeneous disorder that presents as a major cause of persistent and recurrent hypoglycemia during infancy and childhood. There are 16 subtypes of CHI-related genes. Phosphomannomutase 2 hyperinsulinemia (PMM2-HI) is an extremely rare subtype which is first reported in 2017, with only 18 families reported so far. This review provides a structured description of the genetic pathogenesis, and current diagnostic and therapeutic advances of PMM2-HI to increase clinicians' awareness of PMM2-HI.

C.487C>T mutation in PAX4 gene causes MODY9: A case report and literature review.

RATIONALE: Maturity-onset diabetes of the young (MODY) is a group of autosomal dominant monogenic diabetes mellitus with a wide range of clinical manifestations that require distinct treatment strategies. MODY9 (OMIM # 612225) is a rare type of MODY, caused by a mutation in the Paired box gene 4 (PAX4). PATIENT CONCERN: A 19-months boy was admitted to the department of endocrinology at Beijing Children's Hospital due to excessive water drinking, polyuria for over half a month, and wheezing for 3 days. DIAGNOSE: The whole-exon sequencing analysis demonstrated that the child carried the heterozygous missense mutation of c.487>T in the 7th exon region of PAX4 gene and diagnosed MODY9. INTERVENTION: The patient was treated with fluid therapy, ketosis correction, insulin, and anti-infection treatment. OUTCOMES: After 17 days in the hospital, the blood glucose levels remained stable and the patient was discharged. LESSONS: In Chinese children, the heterozygous mutation of c.487C>T in the PAX4 gene can lead to the occurrence of MODY9.Gene sequencing analysis is of great significance in the diagnosis and classification of MODY.

Genetic pathogenesis, diagnosis, and treatment of short-chain 3-hydroxyacyl-coenzyme A dehydrogenase hyperinsulinism.

Congenital hyperinsulinism (CHI), a major cause of persistent and recurrent hypoglycemia in infancy and childhood. Numerous pathogenic genes have been associated with 14 known genetic subtypes of CHI. Adenosine triphosphate-sensitive potassium channel hyperinsulinism (KATP-HI) is the most common and most severe subtype, accounting for 40-50% of CHI cases. Short-chain 3-hydroxyacyl-coenzyme A dehydrogenase hyperinsulinism (SCHAD-HI) is a rare subtype that accounts for less than 1% of all CHI cases that are caused by homozygous mutations in the hydroxyacyl-coenzyme A dehydrogenase (HADH) gene. This review provided a systematic description of the genetic pathogenesis and current progress in the diagnosis and treatment of SCHAD-HI to improve our understanding of this disease.

Retrospective analysis of 23 Chinese children with congenital hyperinsulinism undergoing pancreatectomy.

INTRODUCTION: The aim of the study was to discuss therapeutic effect and prognosis of pancreatectomy in the treatment of congenital hyperinsulinism (CHI). MATERIAL AND METHODS: A total of 23 Chinese children with CHI, who had undergone pancreatectomy, were selected as the study objects. The clinical data, the results of the ¹8Fluoro-L-3-4 dihydroxyphenylalanine positron emission tomography/computerized tomography (¹8F-DOPA PET/CT) scanning, and the diagnosis, treatment, and follow-up were analysed retrospectively. RESULTS: Among the 23 cases, 14 patients were diagnosed with focal-type CHI via a ¹8F-DOPA PET/CT scan prior to the operation, with the lesions removed via partial pancreatectomy. After the operation, ten patients (71%) had normal blood glucose levels, while frequent feeding was required in four patients (29%) to control the hypoglycaemia. Three cases were diagnosed as diffuse-type CHI via preoperative scanning, two of which were treated by subtotal pancreatectomy. The other case was treated by near-total pancreatectomy, and the blood glucose level was normal following the operation. The remaining six cases were not diagnosed via the pancreatic scanning prior to the operation due to the limitation of certain conditions. Here, pancreatectomy was performed directly due to severe hypoglycaemia. CONCLUSIONS: ¹8F-DOPA PET/CT scanning was a reliable method for determining the histological type and localizing the lesion before the operation. Partial pancreatectomy for focal-type CHI had a high cure rate.

Analysis of clinical and genetic characteristics of Chinese children with congenital hyperinsulinemia that is spontaneously relieved.

OBJECTIVE: This study aimed to analyze the clinical and genetic characteristics of Chinese children with congenital hyperinsulinemia (CHI) that is spontaneously relieved. METHODS: The patient group comprised 200 children with CHI that were treated at the Beijing Children's Hospital from January 2006 to December 2018. The patients were divided into two groups according to their prognosis: the spontaneous remission group (n = 92) and the nonspontaneous remission group (n = 108). The clinical characteristics, pathogenic genes, diagnosis and treatment process, and follow-up data of both groups were analyzed retrospectively. RESULTS: Of the 200 children with CHI, 92 achieved spontaneous remission. The age of spontaneous remission was between one month and nine years, and 47 of the children were relieved before the age of one year. The median age of onset was 85 days (range: 1-2825 days) in the spontaneous remission group and 2 days (range: 1-210 days) in the nonspontaneous remission group (P < 0.05). The mean birth weight was 3.44 ± 0.76 kg for the spontaneous remission group and 3.95 ± 0.75 kg for the nonspontaneous remission group (P < 0.05). Of the 92 children in the spontaneous remission group, 65 were treated with diazoxide with effective rate of 81.5% (53/65). In 12 cases in which diazoxide treatment failed, octreotide was used with an effective rate of 83.3% (10/12). Of the 108 children in the nonspontaneous remission group, 88 were treated with diazoxide with an effective rate of 43.2 % (38/88), and 29 children were treated with octreotide with an effective rate of 48.28% (14/29). Of the 30 children in the spontaneous remission group that underwent mutation analysis of CHI-related pathogenic genes, 10 children (10/30, 33.3%) carried mutations. Of the 48 children in the nonspontaneous remission group that underwent mutation analysis of CHI-related pathogenic genes, 37 children (37/48, 77.1%) were found to carry mutations. All of the differences in the indices mentioned above were statistically significant. CONCLUSIONS: The rate of spontaneous remission of CHI was significantly higher in children with late age of CHI onset, light birth weight, effective diazoxide treatment, and no common pathogenic gene mutations. Spontaneous remission was also possible for a small number of children that carried mutations in the ABCC and KCNJ11 genes and in whom diazoxide treatment failed.

MODY10 caused by c.309-314del CCAGCT insGCGC mutation of the insulin gene: a case report.

OBJECTIVE: This study aims to report the clinical features and gene mutation of a rare MODY10 patient in China. METHODS: This study summarizes the clinical data of a MODY10 child in the Endocrine Department of our hospital and an analysis and discussion of the results of the gene sequencing of the child. RESULTS: The child was a two-year-old boy. The main reason for his visit to our hospital was "founding hyperglycemia for 3 days". The fasting blood glucose was between 8.1-10.7 mmol/L, and two-hour postprandial blood glucose was between 10.6-12.6 mmol/L. Glycosylated hemoglobin was 8.5%, fasting C-peptide was 0.6 ng/mL, fasting insulin was 2.9 µIU/mL, and the islet antibody series were all negative. Whole-genome/exon sequencing results: Exon 3 of the insulin gene in the child carried a c.309-314del CCAGCT insGCGC heterozygous mutation. The mutation was a nonsense mutation, and family sequencing showed that the mutation originated from the mother of the child. The mother of the child was diagnosed with diabetes when she was a year old and developed bilateral fundus hemorrhage and right retinal detachment at the age of 23. CONCLUSION: Among Chinese children, the insulin gene c.309-314del CCAGCT insGCGC mutation may induce MODY10. For diabetic children with a negative islet autoantibody, gene detection and analysis is helpful for the diagnosis and typing of MODY.

[Floating-Harbor syndrome: a case report and literature review].

Floating-Harbor syndrome (FHS) is an autosomal dominant genetic disease caused by SRCAP mutation. This article reports the clinical features of a boy with FHS. The boy, aged 11 years and 7 months, attended the hospital due to short stature for more than 8 years and had the clinical manifestations of unusual facial features (triangularly shaped face, thin lips and long eyelashes), skeletal dysplasia (curvature finger), expressive language disorder, and retardation of bone age. Genetic detection revealed a novel heterozygous mutation, c.7330 C>T(p.R2444X), in the SRCAP gene. The boy was diagnosed with FHS based on these clinical manifestations and gene detection results. FHS is rare in clinical practice, which may lead to missed diagnosis and misdiagnosis, and gene detection may help with the clinical diagnosis of FHS in children.

Analysis on the pathogenic genes of 60 Chinese children with congenital hyperinsulinemia.

This study aims to summarize and analyze the clinical manifestations, genetic characteristics, treatment modalities and long-term prognosis of congenital hyperinsulinemia (CHI) in Chinese children. Sixty children with CHI, who were treated at Beijing Children's Hospital from January 2014 to August 2017, and their families, were selected as subjects. The CHI-related causative genes in children were sequenced and analyzed using second-generation sequencing technology. Furthermore, the genetic pathogenesis and clinical characteristics of Chinese children with CHI were explored. Among the 60 CHI children, 27 children (27/60, 45%) carried known CHI-related gene mutations: 16 children (26.7%) carried ABCC8 gene mutations, seven children (11.7%) carried GLUD1 gene mutations, one child carried GCK gene mutations, two children carried HNF4α gene mutations and one child carried HADH gene mutations. In these 60 patients, 8 patients underwent 18F-L-DOPA PET scan for the pancreas, and five children were found to be focal type. The treatment of diazoxide was ineffective in these five patients, and hypoglycemia could be controlled after receiving partial pancreatectomy. Conclusions: ABCC8 gene mutation is the most common cause of CHI in Chinese children. The early genetic analysis of children's families has an important guiding significance for treatment planning and prognosis assessment.

Differential stem cell aging kinetics in Hutchinson-Gilford progeria syndrome and Werner syndrome.

Hutchinson-Gilford progeria syndrome (HGPS) and Werner syndrome (WS) are two of the best characterized human progeroid syndromes. HGPS is caused by a point mutation in lamin A (LMNA) gene, resulting in the production of a truncated protein product-progerin. WS is caused by mutations in WRN gene, encoding a loss-of-function RecQ DNA helicase. Here, by gene editing we created isogenic human embryonic stem cells (ESCs) with heterozygous (G608G/+) or homozygous (G608G/G608G) LMNA mutation and biallelic WRN knockout, for modeling HGPS and WS pathogenesis, respectively. While ESCs and endothelial cells (ECs) did not present any features of premature senescence, HGPS- and WS-mesenchymal stem cells (MSCs) showed aging-associated phenotypes with different kinetics. WS-MSCs had early-onset mild premature aging phenotypes while HGPS-MSCs exhibited late-onset acute premature aging characterisitcs. Taken together, our study compares and contrasts the distinct pathologies underpinning the two premature aging disorders, and provides reliable stem-cell based models to identify new therapeutic strategies for pathological and physiological aging.

Mutational analysis of ABCC8, KCNJ11, GLUD1, HNF4A and GCK genes in 30 Chinese patients with congenital hyperinsulinism.

We conducted a cohort study to elucidate the molecular spectrum of congenital hyperinsulinism (CHI) in Chinese pediatric patients. Thirty Chinese children with CHI were chosen as research subjects, 16 of whom were responsive to diazoxide and 13 of whom were not (1 patient was not given the drug for medical reasons). All exons of the adenosine triphosphate (ATP)-sensitive potassium channel (KATP channel) genes KCNJ11 and ABCC8, the hepatocyte nuclear factor 4 α (HNF4A) gene, and the Glucokinase (GCK) gene as well as exons 6 and 7 and 10-12 of the glutamate dehydrogenase 1 (GLUD1) gene were amplified from genomic DNA and directly sequenced. Mutations were identified in 14 of 30 patients (47%): 3 in GLUD1 (10%) and 11 in the KATP channel genes (37%). Six patients had paternally derived monoallelic KATP channel mutations predictive of the focal CHI form. We found a novel de novo ABCC8 mutation, p. C1000*, a novel paternally inherited ABCC8 mutation, D1505H, and a dominantly inherited ABCC8 mutation, R1217K. The GLUD1 activating mutation R269H was found in 2 patients: 1 de novo and the other paternally inherited. A de novo S445L mutation was found in 1 patient. No significant HNF4A or GCK mutations were found. CHI has complex genetic onset mechanisms. Paternally inherited monoallelic mutations of ABCC8 and KCNJ11 are likely the main causes of KATP-CHI in Chinese patients. Glutamate dehydrogenase-CHI is the second most common cause of CHI, while HNF4A and GCK are rare types of CHI in Chinese patients.

KCNJ11 gene mutation analysis on nine Chinese patients with type 1B diabetes diagnosed before 3 years of age.

AIM: The term type 1B diabetes mellitus (T1BDM) refers tonon-autoimmune-mediated type 1 diabetes. Recent studies revealed that monogenic mutations contribute to the genetic onset mechanism of this group. In this study, nine patients with T1BDM were selected as research subjects, and the 5' untranslated region and the exon of KCNJ11 gene were sequenced in order to study the genetic onset mechanism of T1BDM. METHODS: Nine patients with T1BDM diagnosed before 3 years of age were selected as research subjects. Genomic DNA was extracted from peripheral leukocytes using standard procedures. The 5' untranslated region and the exon of the KCNJ11 gene were sequenced using PCR-DNA assay techniques. RESULTS: A heterozygous c.1096G>T (G366W) mutation was identified in a patient diagnosed as type 1B diabetes at the age of 19 months, and the patient's father carried the same mutation. The genotype of the patient's mother was normal, indicating that this mutation was autosomal dominantly inherited. No KCNJ11 mutations were found in other patients. This patient suffered only from type 1B diabetes, not accompanied with neurological developmental abnormalities. CONCLUSION: Monogenic mutation may be one of the main causes of early onset T1BDM. A KCNJ11 gene G366W mutation can lead to the onset of T1BDM in Chinese children. The patient with KCNJ11 G366W mutation suffered only type 1B diabetes, without neurological developmental abnormalities.

Clinical analysis on 33 patients with hypothalamic syndrome in Chinese children.

AIM: To investigate the etiology and clinical characteristics of hypothalamic syndrome in Chinese children. METHODS: Thirty-three cases of hypothalamic syndrome were analyzed for etiology, initial symptoms, and clinical characteristics. RESULTS: All of the 33 patients manifested symptoms of hypothalamic dysfunction and disorders of the hypothalamus-hypophysis-target gland axis. Fourteen patients were diagnosed with an intracranial tumor by magnetic resonance imaging (MRI) examination, four patients had postoperative intracranial tumors, one had received radiotherapy for suprasellar germinoma, one was hypothalamic-pituitary dysplasia, one had a history of viral encephalitis, and in 12 patients, the cause was unknown. The most common presenting symptoms were polydipsia/polyuria and eating disorders. CONCLUSION: Intracranial tumor is an important cause of hypothalamic syndrome in children, with germinoma the most common. Polydipsia, polyuria, and eating disorders are typical presenting symptoms. Long-term follow-up is needed for patients presenting with central diabetes insipidus, eating disorders or hypothalamic syndrome of unknown etiology. In addition, periodic pituitary MRI scanning is necessary to find potential intracranial tumors that may arise at any time.