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, eight 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. In conclusion, 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.
Zi-Di Xu, Wei Zhang, Min Liu, Huan-Min Wang, Pei-Pei Hui, Xue-Jun Liang, Jie Yan, Yu-Jun Wu, Yan-Mei Sang, Cheng Zhu and Gui-Chen Ni
Peng Fan, Chao-Xia Lu, Di Zhang, Kun-Qi Yang, Pei-Pei Lu, Ying Zhang, Xu Meng, Su-Fang Hao, Fang Luo, Ya-Xin Liu, Hui-Min Zhang, Lei Song, Jun Cai, Xue Zhang and Xian-Liang Zhou
Background: Liddle syndrome (LS) is a monogenetic autosomal dominant disorder. Clinically, misdiagnosis or missing diagnosis is common, since clinical phenotypes are variable and nonspecific, always mimicking primary aldosteronism (PA). We report a family with clinical suspicion of PA, but identify as LS with a pathogenic frameshift mutation of the epithelial sodium channel (ENaC) β subunit.
Patients and methods: DNA samples were collected from a 32-year-old proband and 31 other relatives in the same family. They were sequenced for mutations in exon 13 of the α-ENaC, β-ENaC and γ-ENaC genes, using amplification by polymerase chain reaction and direct DNA sequencing.
Results: Genetic analysis of the proband revealed a novel frameshift mutation c.1838delC (p.P613Qfs*63) in exon 13 of SCNN1B. This heterozygous mutation involved the deletion of a cytosine from a string of three consecutive cytosines located at codons 612 to 613 and resulted in deletion of the crucial PY motif and elongation of the β-ENaC protein. The identical mutation was also found in 12 affected family members. Amiloride was effective in alleviating LS for patients. There were no SCNN1A or SCNN1G mutations in this family.
Conclusions: Our study emphasizes the importance of considering LS in the differential diagnosis of secondary hypertension. And it indicates that genetic testing is confirmatory evidence in management of suspected LS patients. The identification of a novel frameshift mutation of SCNN1B enriches the genetic spectrum of LS, and has allowed treatment of this affected family to prevent complications.