OBJECTIVE: To explore the clinical characteristics and genetic basis for three children with Congenital chlorine diarrhea (CCD). METHODS: Three children with CCD who attended the Affiliated Children's Hospital of Capital Pediatric Institute from June 2014 to August 2020 were selected as the research subjects. Peripheral blood samples of the three children and their parents were collected for genetic testing. And the results were verified by Sanger sequencing. RESULTS: The clinical manifestations of the three children have included recurrent diarrhea, with various degrees of hypochloremia, hypokalemia and refractory metabolic alkalosis. Genetic testing revealed that the three children have all carried variants of the SLC26A3 gene, including homozygous c.1631T>A (p.I544N) variants, c.2063_1G>T and c.1039G>A (p.A347T) compound heterozygous variants, and c.270_271insAA(p.G91kfs*3) and c.2063_1G>T compound heterozygous variants. Sanger sequencing confirmed that all of the variants were inherited from their parents. CONCLUSION The variants of the SLC26A3 gene probably underlay the CCD in these children. Above finding has enriched the spectrum of SLC26A3 gene variants.
Humans ; Child ; Chlorine ; Genetic Testing ; Hypokalemia/genetics* ; Homozygote ; Diarrhea/genetics* ; Mutation

Objective:To investigate the clinical and genetic characteristics of congenital isolated adrenocorticotropic hormone (ACTH) deficiency.Methods:The clinical and laboratory characteristics of 5 cases with congenital isolated ACTH deficiency diagnosed in the Department of Endocrinology of the Children′s Hospital, Capital Institute of Pediatrics from January 2019 to March 2021 were retrospectively analyzed. The general conditions, clinical manifestations, laboratory examinations, genetic charcteistics, treatment and follow-up (up to October 2021) were analyzed.Results:Of the 5 cases, 1 was female and 4 were males, aged from 13 months to 6 years at the time of consultation. The symptoms of hypoglycemia and convulsion were presented in infancy, and 4 cases had infantile cholestasis. Glucose level of 5 cases ranged from 0.79-2.20 mmol/L, ACTH ranged from <1.00-4.17 ng/L, and cortisol ranged from 0.2-3.8 &mu;g/L. Whole exon sequencing revealed that 3 cases carried homozygous TBX19 variations, and 2 cases had compound heterozygous TBX19 variations, including 3 variants that had been reported before and 3 novel variants were found. After the diagnosis was confirmed, all the cases were treated with hydrocortisone. Hypoglycemia was all corrected during the follow-up, and 4 cases no longer had convulsions.Conclusion:Congenital isolated ACTH deficiency should be considered in neonates and infants with cholestasis and hypoglycemia, and the diagnosis can be confirmed by genetic testing.

A 15-month-old baby girl presenting with hypoglycemia was admitted in Children′s Hospital of Capital Institute of Pediatrics in October 2019. The blood glucose level was 2.4 mmol/L at admission, she showed asymmetry of left and right limbs. The levels of D-3-hydroxybutyric acid, urinary ketone body and free fatty acid were all decreased during hypoglycemia attack, the hyperglycemic hormone was increased, but insulin level was<0.2 &mu;IU/ml. The whole exon gene testing showed that the patient had heterozygous mutation of AKT2 gene c.49G>A (p.E17K), which was mosaicism; then the patients was diagnosed as hypoinsulinemic hypoketotic hypo-fatty-acidemic hypoglycemia due to mutation of AKT2 gene. Blood glucose levels were dynamically monitored, high carbohydrate diet was administered and raw corn starch supplementation was given before bedtime. After 18 months of treatment, the growth and development of the patient was normal, the frequency of hypoglycemia attacks decreased, and bilateral limb asymmetry improved. The relevant literature was searched from Wanfang Database, CNKI and PubMed from January 1980 to March 2021 by using search term"hypoglycemia"and"AKT2 gene". Five cases of hypoglycemia caused by AKT2 mutation were retrieved, all were reported from other countries, no one case from China. The clinical manifestation of this disease is similar to hyperinsulinemic hypoglycemia, but insulin could not be detected during the attack of hypoglycemia, and the patients may have hemihypertrophy. The study suggests that if the patient has hypoglycemia accompanied by hypoinsulinemia and hemihypertrophy, we should consider the possibility of AKT2 gene mutation, and genetic testing should be recommended.

OBJECTIVE: To summarize clinical manifestations and results of genetic testing in 12 children with Gitelman syndrome (GS). METHODS: Clinical data of the children was collected. Whole exome sequencing(WES) was carried out to screen potential variants of genomic DNA. Candidate variants were verified by Sanger sequencing. RESULTS: The patients have included 10 boys and 2 girls, whom were diagnosed at between 2.8 to 15.0 year old. Six patients were due to infections, 5 were due to short stature, and 1 was due to lower limb weakness. All patients were found to carry variants of SLC12A3 gene, which included 11 with compound heterozygous variants and 1 with homozygous variant. All of the 19 alleles of the SLC12A3 gene carried by the patients were delineated, which included 15 missense variants, 2 frameshift variants and 2 splice region variants. These variants were unreported previously, which included c.578_582dupCCACC (p.Asn195Profs*109), c.251C>T (p.Pro84Leu) and c.2843G>A (p.Trp948X). CONCLUSION The clinical symptoms of GS in children are atypical and often seen in older children. For children with occasional hypokalemia associated with growth failure, GS should be suspected. The majority of GS children carry two pathogenic variants of the SLC12A3 gene, mainly compound heterozygotes, among which p.Thr60Met is the most common one. The discovery of new variants has enriched the spectrum of SLC12A3 gene variants.
Adolescent ; Child ; Child, Preschool ; DNA ; Female ; Genetic Testing ; Gitelman Syndrome/genetics* ; Humans ; Hypokalemia/genetics* ; Male ; Solute Carrier Family 12, Member 3/genetics*

Objective:To analyze the clinical and genetic characteristics of primary hypoparathyroidism in children.Methods:The clinical data including age, symptoms, laboratory examination and cranial CT of 13 children with primary hypoparathyroidism diagnosed in the Capital Institute of Pediatrics from May 2017 to December 2019 were collected and analyzed retrospectively. These children and their parents also had gene detected by whole exome sequencing and (or) copy number variation sequencing.Results:Among the 13 patients, 7 were male and 6 female. The onset age was 3 years (1 day-12 years) old. The time from onset to confirmed diagnosis was 2 months (2 days-10 years). The clinical manifestations included convulsion (9 cases), tetany (2 cases), muscle pain (1 case), mental retardation (5 cases), deafness (1 case), and initially misdiagnosed epilepsy (5 cases). The lab examination showed average blood calcium level of (1.7±0.3) mmol/L, blood phosphorus of (2.8±0.4) mmol/L, and parathyroid hormone of 8.2 (3.9-28.7)ng/L. Head CT found 7 cases of ectopic calcification. Among the 7 cases who had genetic abnormalities according to the gene detection, 5 had heterozygous deletion of 22q11.2 region, and only one of whom was diagnosed with typical DiGeorge syndrome. As for the rest 2 cases, one had autosomal dominant hypocalcemia caused by novel heterozygous variation of CaSR gene c.2495T>G (p.F832C), and the other was hypoparathyroidism-deafness-renal dysplasia syndrome caused by GATA3 c.708dupC (p.S237Qfs*66) novel heterozygous variation.Conclusions:Primary hypoparathyroidism in children is mainly characterized by hypocalcemia and usually accompanied with diverse symptoms which may indicate genetic disorders. The detection of large fragment deletion should be considered to exclude 22q11.2 deletion syndrome.

OBJECTIVE: To explore the genetic basis for a child with neonatal severe hyperparathyroidism. METHODS: Genomic DNA was extracted from peripheral blood samples from the patient and her parents. Whole exome sequencing was carried out to screen potential mutations. Suspected mutation was verified by Sanger sequencing. RESULTS: The proband was found to carry compound heterozygous variants c.179G>A (p.Cys60Tyr) and c.1525G>A (p.Gly509Arg) of the CaSR gene. The c.179G>A variant was derived from her mother and was unreported previously. The c.1525G>A variant was derived from her father and known to be pathogenic. CONCLUSION The compound heterozygous variants of c.179G>A and c.1525G>A of the CaSR gene probably underlie the disease in the patient. The results of genetic testing has enabled diagnosis and genetic counseling for her family.
Female ; Genetic Counseling ; Genetic Testing ; Humans ; Hyperparathyroidism/genetics* ; Infant, Newborn ; Infant, Newborn, Diseases/genetics* ; Mutation ; Pedigree ; Receptors, Calcium-Sensing/genetics* ; Whole Exome Sequencing

Objective: To investigate the clinical features and genetic characteristics of patients with ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) gene variants. Method: The clinical data of a patient with ENPP1 homozygous variants from Capital Institute of Pediatrics was collected, the related literature was searched from China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, National Center from Biotechnology Information and PubMed by using search term "ENPP1" , "hypophosphatemic rickets" . The literature retrieval was confined from 1980 to February 2017. The clinical manifestations, bone metabolism examinations, X-RAY and genotypes were reviewed. Result: Our patient was an 11 years old girl, with 7 years history of lower limb malformation. She showed significant valgus deformity of the knee (genu valgum). Metabolic examination revealed reduced level of plasma phosphate (0.86 mmol/L), a normal level of plasma calcium (2.30 mmol/L) and an elevated alkaline phosphatase level of 688 IU/L. The calcium-phosphorus product was 25.9. A homozygous nonsense variants of ENPP1 gene, c.783C>G (p.Tyr261X) in exon 7 was identified in the patient. Both parents were heterozygous carriers. Literature review identified 3 Chinese patients from one publication and 17 cases from twenty one publications around the world. None of the patients was found PHEX variants which is the most common variants among hypophosphatemic rickets patients. The disease onset age was 11 months to 10 years. Eight patients had short stature, five patients had the history of generalized arterial calcification of infancy. Four suffered from deafness, three showed localized calcifications of arteries, three patients manifested pseudoxanthoma elasticum and two suffered from ossification of posterior longitudinal ligament. Nine missense variants, six splicing variants and 4 nonsense variants were reported among these twenty patients. c.783C>G was found in two Chinese patients. Conclusion ENPP1 gene mutation was a cause of patient with hypophosphatemic rickets. Comorbid features included generalized arterial calcification of infancy, early onset hearing loss, pseudoxanthoma and ossification of posterior longitudinal ligament. ENPP1 gene testing should be performed on hypophosphatemic rickets patients without PHEX gene variants. Long-term follow up is recommended. The most common types of ENPP1 gene variants were nonsense/splicing variants. The gene c.783C>G was the most common variants in Chinese patients.

Objective To report clinical characteristics and genetic results of two sisters suffered from congenital adrenal cortex hyperplasia (17-α-hydroxylase deficiency), and relevant literatures were reviewed. Methods Clinical manifestation and laboratory examination data of two sister cases of 17-α-hydroxylase deficiency enrolled in Capital Institute of Pediatrics in March 2016 were analyzed. Sanger sequencing and MLPA for CYP17A1 genes were performed and the parents' genes were also verified. Results The two patients were four years and 10 years old, both suffered from hypokalemia after infections, and hypergonadotrophin gonad hypofunction. One case was with slightly high blood pressure. Laboratory test results showed potassium fluctuation tendency in 1.9~4.0 mmol/L, 17-OHP and DHEA was decreased. Enhanced CT showed different degree of adrenal gland enlargement. Chromosome examination of the older sister is 46, XY. Both sisters demonstrated heterozygous mutation of CYP17A1 gene. The molecular genetic analysis suggested a c.985_987delTACinsAA from father and a deletion spanning exons 1-7 of the CYP17A1 gene from mother. Conclusion 17-α-hydroxylase enzyme deficiency can be diagnosed before adolescence. Clinical hypokalemia with unknown reason and high blood pressure may indicate the disease. The diagnosis can be confirmed with gene sequencing of CYP17A1.

Objective:To investigate the relationship between DNA methyltransferase (DNMT1) and EZH2 gene expression levels and their clinical significance in patients with acute myeloid leukemia (AML). Methods:The mRNA expression levels of DNMT1 and EZH2 in 50 AML cases and 30 healthy controls were quantified through real-time PCR. The relationship among DNA methyltransferase (DNMT1) and EZH2, clinicopathological factors, and prognosis was analyzed. Results:The mRNA expression of DNMT1 in the AML cases (2.72 ± 0.73) was significantly higher than that in the healthy controls (0.89 ± 0.27) (P<0.01). The mRNA expression of EZH2 in the AML cases (4.39±1.06) was also significantly higher than that in the healthy controls (1.87±0.33) (P<0.01). The expression of DNMT1 was positive-ly associated with that of EZH2 (r=0.51, P=0.002). The expression of DNMT1 was also associated with PB%and WBC≥50 × 109/L (P<0.05). The overall survival of the group with a high-mRNA-expressing DNMT1 was 15 months (95%CI=9-19 months). This period was significantly shorter than that of the group with low-mRNA-expressing DNMT1 (32 months, 95%CI=27-40 months;P=0.006). Conclu-sion:DNMT1 and EZH2 expression levels were downregulated. These levels were associated with poor AML prognosis. The expression of DNMT1 was also positively associated with that of EZH2.

Objective To analyze the stability and accuracy of the equipment for three-dimensional ultrasound-based image-guided radiation therapy (3DUS-IGRT) in daily practice, and to provide a basis for clinical application of radiotherapy for soft tissue tumors.Methods A specific calibration phantom was used for continuous calibration and quality control of the 3DUS-IGRT equipment in a year.The method for daily quality control of ultrasound-guided equipment was explored, and its stability and accuracy were monitored.Results The phantom position errors in both Sim and Guide stations of the 3DUS-IGRT equipment were within 1 mm.Conclusions The 3DUS-IGRT equipment has a stable performance with the support of a complete set of stringent and accurate calibration and quality control, which provides a new image-guided method for precise radiotherapy for soft tissue tumors.