To explore the approaches and diagnostic yield of genetic testing for renal disease in children, we describe the genotype and phenotype of the national cohort of children with renal disease from 13 different regions of China recruited from 2014 to 2018 by building up the multicenter registration system (Chinese Children Genetic Kidney Disease Database, CCGKDD). Genetic diagnosis was confirmed in 42.1% of our cohort of 1001 pediatric patients with clinical suspicion of a genetic renal disease. Of the 106 distinct monogenetic disorders detected, 15 accounted for 60.7% of genetic diagnoses. The diagnostic yield was 29.1% in steroid resistant nephritic syndrome (SRNS), 61.4% in cystic renal disease, 17.0% in congenital anomalies of the kidney and urinary tract (CAKUT), 62.3% in renal tubular disease/renal calcinosis, and 23.9% for chronic kidney disease (CKD) 3 to 5 stage with unknown origin. Genetic approaches of target gene sequence (TGS), singleton whole‐exome sequencing (WES) and trio‐WES were performed with diagnostic rates of 44.8%, 36.2%, and 42.6%, respectively. The early use of trio‐WES could improve the diagnostic rate especially in renal tubular disease and calcinosis. We report the genetic spectrum of Chinese children with renal disease. Establishment of the CCGKDD will improve the genetic work on renal disease.

BackgroundThe incidence of AKI appears to have increasing trend. Up to now, prospective, multi-center, large-sample epidemiological study done on pediatric AKI on aspects of epidemiological characteristics, causes and outcomes have not reported. It is necessary to develop prospective, multi-center, large-sample epidemiological study in our country on pediatric AKI. The aim of this study was to determine the clinical features, etiology, and outcomes of acute kidney injury (AKI) in Chinese children.MethodPaediatric patients (≤18 years old) admitted to 27 hospitals (14 children’s hospitals and 13 general hospitals) affiliated with the Medical University were investigated. AKI was defined using the 2005 Acute Kidney Injury Network criteria.ResultsDuring the study period, 388,736 paediatric patients were admitted. From this total, AKI was diagnosed in 1,257 patients, 43 of whom died. The incidence and mortality of AKI was 0.32% and 3.4% respectively. The mean (± SD) age of patients was 48.4 ± 50.4 months. Among the 1,257 AKI paediatric patients, 632 were less than one year old. Among the AKI paediatric patients, 615 (48.9%) were in stage 1, 277 (22.0%) in stage 2, and 365 (29.0%) in stage 3. The most common causes of AKI were renal causes (57.52%), whereas postrenal (25.69%) and prerenal (14.96%) causes were the least common. The three most common causes of AKI according to individual etiological disease were urolithiasis (22.35%), of which exposure to melamine-contaminated milk accounted for the highest incidence (63.7%); acute glomerulonephritis (10.10%); and severe dehydration (7.48%). A total of 43 AKI patients (3.4%) died during their hospital stay; 15 (34.9%) of the 43 died as a result of sepsis.ConclusionPrimary renal diseases are a major risk factor for paediatric AKI in China. In terms of specific etiological disease, urolithiasis (postrenal disease) was the leading cause of paediatric AKI in 2008, when the disease was linked to exposure to melamine-contaminated milk. Sepsis is the leading cause of death in Chinese paediatric AKI patients. Future studies should focus on effective ways of controlling renal disorders and sepsis to improve the clinical management of paediatric AKI in China.

Background/Aims: The study aims to elucidate the roles of 1,25(OH)₂D₃ and vitamin D receptor (VDR) in the pathogenesis of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) by regulating the activation of CD4⁺ T cells and the PKCδ/ERK signaling pathway. Methods: From January 2013 to December 2015, a total of 130 SLE patients, 137 RA patients and 130 healthy controls were selected in this study. Serum levels of 1,25(OH)₂D₃ and VDR mRNA expression were detected by ELISA and real-time fluorescence quantitative PCR (RT-qPCR). Density gradient centrifugation was performed to separate peripheral blood mononuclear cells (PBMCs). CD4⁺ T cells were separated using magnetic activated cell sorting (MACS). CD4⁺T cells in logarithmic growth phase were collected and assigned into 9 groups: the normal control group, the normal negative control (NC) group, the VDR siRNA group, the RA control group, the RA NC group, the VDR over-expressed RA group, the SLE control group, the SLE NC group, and the VDR over-expressed SLE group. The mRNA and protein expressions of VDR, PKCδ, ERK1/2, CD11a, CD70 and CD40L were detected by RT-qPCR and Western blotting. Bisulfite genomic sequencing was conducted to monitor the methylation status of CD11a, CD70 and CD40L. Results: Compared with healthy controls, serum 1,25(OH)₂D₃ level and VDR mRNA expression in peripheral blood were decreased in SLE patients and RA patients. With the increase of concentrations of 1,25(OH)₂D₃ treatment, the VDR mRNA expression and DNA methylation levels of CD11a, CD70 and CD40L were declined, while the expressions of PKCδ, ERK1/2, CD11a, CD70 and CD40L were elevated in SLE, RA and normal CD4⁺T cells. Compared with the SLE contro, RA control, SLE NC and RA NC groups, the expressions of PKCδ, ERK1/2, CD11a, CD70 and CD40L decreased but DNA methylation levels of CD11a, CD70 and CD40L increased in the VDR over-expressed SLE group and VDR over-expressed RA group. However, compared with the normal control and normal NC groups, the expressions of PKCδ, ERK1/2, CD11a, CD70 and CD40L increased, but DNA methylation levels of CD11a, CD70 and CD40L decreased in the VDR siRNA group. Compared with the normal control group, the expressions of PKCδ, ERK1/2, CD11a, CD70 and CD40L increased, but DNA methylation levels of CD11a, CD70 and CD40L decreased in the SLE control and RA control groups. Conclusion: Our study provide evidence that 1,25(OH)₂D₃ and VDR could inhibit the activation of CD4⁺ T cells and suppress the immune response of SLE and RA through inhibiting PKCδ/ERK pathway and promoting DNA methylation of CD11a, CD70 and CD40L.