Genetic analysis of a child with atypical Hemolytic uremic syndrome and nephrotic-range proteinuria / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical characteristics and genetic etiology for a child with atypical Hemolytic uremic syndrome (aHUS) in conjunct with nephrotic level proteinuria.@*METHODS@#A child patient who had visited the Affiliated Hospital of Qingdao University on June 25, 2020 was selected as the study subject. Clinical data of the patient was collected. Whole exome sequencing (WES) was carried out for the child, and candidate variant was verified by Sanger sequencing of the child and his parents.@*RESULTS@#The child, an 8-month-old male, had presented mainly with edema, oliguria, hematuria, nephrotic level proteinuria, anemia, thrombocytopenia, increased creatinine and urea, hypercholesterolemia but normal complement levels. Genetic testing revealed that he has harbored compound heterozygous variants of the DGKE gene, namely c.12_18dupGAGGCGG (p.P7fs*37) and c.1042G>T (p.D348Y), which were respectively inherited from his father and mother. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variants were classified as likely pathogenic and variant of uncertain significance, respectively. By combining his clinical manifestations and results of genetic testing, the child was diagnosed with aHUS with nephrotic level proteinuria.@*CONCLUSION@#For infants and young children with aHUS in conjunct with nephrotic level proteinuria, variants of the DGKE gene should be screened. Above finding has expanded the mutational spectrum of the DGKE gene.

Proteinuria in cystic fibrosis: a possible correlation between genotype and renal phenotype / Proteinúria na fibrose cística: possível correlação entre genótipo e fenótipo renal

Objective: To assess proteinuria in patients with cystic fibrosis (CF), and to correlate proteinuria with genotype, CF-related diabetes and disease severity. Methods: A prospective study was carried out over a six-month period and involving 22 CF patients. After the collection and analysis of 24-h urine samples, the patients were divided into two subgroups: protein excretion < 150 mg/day (low-proteinuria); and protein excretion ≥ 150 mg/day (highproteinuria). Patient charts were reviewed to obtain data on genotype and CF-related diabetes. Disease severity was assessed based on acute exacerbations in the last six months and FEV1 measured during the study period. To assess the correlation between genotype and proteinuria, the two main mutations (ΔF508 and R334W) were evaluated. Due to the existence of genotype ΔF508/R334W, two categories were created to enable statistical analysis, ΔF508 being evaluated in category 1 and R334W being evaluated in category 2. Results: The ΔF508 mutation tended to be associated with normal protein excretion: 100% of the low-proteinuria subgroup patients were consideredΔF508 in category 1, compared with 86.7% in category 2. Protein excretion tended to be higher in patients withthe R334W mutation: 60.0% of the high-proteinuria subgroup patients were considered R334W in category 1, compared with 80.0% in category 2 (p = 0.009 and p = 0.014, respectively). No significant association was foundfor any of the other variables. Conclusions: The results suggest that genotype is associated with renal phenotype, depending on the mechanism by which the genotype alters the function of the cystic fibrosis transmembrane conductance regulator gene.

Objetivo: Avaliar a proteinúria em pacientes com fibrose cística (FC) e correlacioná-la com o genótipo, com adiabetes relacionada à FC e com a gravidade da doença. Métodos: Estudo prospectivo realizado num período deseis meses com 22 pacientes com FC. Efetuada proteinúria de 24 h com a divisão dos pacientes em dois subgrupos:proteinúria < 150 mg/dia (proteinúria-baixa); e proteinúria ≥ 150 mg/dia (proteinúria-alta). Revisamos os prontuários clínicos para a coleta de informações sobre o genótipo e a presença de diabetes relacionada à FC. A gravidade da doença foi avaliada pelas exacerbações agudas no último semestre e pelo VEF1 durante o período de estudo. Para avaliar a correlação entre genótipo e proteinúria, consideraram-se as duas principais mutações, ΔF508 e R334W. Dada a existência do genótipo ΔF508/R334W, foram criadas duas categorias para se proceder à avaliação estatística, sendo esse genótipo considerado ΔF508 na categoria 1 e R334W na categoria 2. Resultados: A mutação ΔF508 se associou com valores normais de proteinúria: 100% dos pacientes do subgrupo proteinúria-baixa foram considerados ΔF508 na categoria 1, comparados a 86,7% na categoria 2. Em pacientes com a mutação R334W, osvalores de proteinuria foram mais elevados: 60,0% dos pacientes do subgrupo proteinúria-alta foram considerados R334W na categoria 1, comparados a 80,0% na categoria 2 (p = 0,009 e p = 0,014, respectivamente). Para as outras variáveis, não houve associação significativa. Conclusões: Os resultados sugerem que há uma associação entre o genótipo e o fenótipo renal, dependendo do mecanismo pelo qual o genótipo altera a função do generegulador de condutância transmembrana da fibrose cística.

The enabled homolog gene polymorphisms are associated with susceptibility and progression of childhood IgA nephropathy

The enabled homolog gene (ENAH, hMena) is abundantly expressed in mesangial tissue, and might play an important role in inflammatory processes of IgA nephropathy (IgAN). The present study was conducted to investigate the association between single nucleotide polymorphisms (SNPs) of the ENAH and childhood IgAN. We analyzed 12 SNPs of ENAH in 176 patients with childhood IgAN and 397 healthy controls. In addition, IgAN patients were dichotomized and compared with respect to several clinical and pathological parameters. Genotyping data showed significant differences between IgAN patients and controls in the frequency of rs2039620, rs12034829, and rs3795443. On comparison of patients with proteinuria to those without proteinuria ( 4 mg/m2/h), rs12043633 was significantly different between the two groups. With regard to maximum proteinuria ( 4 mg/m2/h), rs3795443, rs4653643, rs6751, rs10799319, rs7555139, rs576861, and rs487591 showed significant allele frequency differences. For patients with and without gross hematuria, rs4653643, rs6751, rs10799319, rs7555139, rs576861, and rs487591 showed significant allele frequency differences. The rs3795443 was found to be associated with progression of pathological findings. Our results suggest that ENAH polymorphisms are associated with increased susceptibility, development of proteinuria and gross hematuria, and pathological progression of childhood IgAN.