Genetic variants of familial hematuria associated genes in three families with hematuria with probands initially diagnosed as IgA nephropathy / 中华儿科杂志

Objective@#To examine genetic variants of familial hematuria (FH) associated genes in 3 families with hematuria with probands initially diagnosed with IgA nephropathy (IgAN).@*Methods@#A retrospective analysis was performed on the clinical data, laboratory tests and genetic test results of three children with hematuria and the probands in three families with hematuria. The families were ascertained at the Department of Pediatrics, Fuzhou General Hospital of Nanjing Military Command from August 2014 to May 2018.@*Results@#The proband of Family One, an 8-year-old boy, manifested gross hematuria. His renal biopsy pathology revealed IgAN. His father also manifested hematuria. Genetic testing showed that the proband and his father carried a heterozygous variant of the CFHR5 gene,533A>G (Asn178Ser). The child of Family Two, a 4-year-old girl, manifested hematuria. Her father, the proband of the family, was 36 years old, and manifested hematuria, proteinuria, high-frequency sensorineural deafness and renal insufficiency. He was diagnosed as IgAN according to clinical manifestations, renal pathology and routine immunohistochemistry without renal biopsy electron microscopy, renal tissue type Ⅳ collagen α3, α4, α5 chains immunofluorescence and skin type Ⅳ collagen α5 chain immunofluorescence. Genetic testing showed that the girl carried a heterozygous variant of the COL4A5 gene,566G>T (Gly189Val), and her father carried the hemizygous variant. The child of Family Three, a 7-year-old girl, manifested hematuria and proteinuria. Her mother, the proband of the family, was 34 years old, and manifested hematuria and proteinuria as well. The proband was diagnosed as IgAN by the same method used for Family Two. The girl′s grandfather died of uremia at the age of 44. Genetic testing showed that the girl and her mother carried a heterozygous variant 539G>A (Gly180Glu)in COL4A5 gene.@*Conclusions@#The variant of the CFHR5 gene identified in Family One is of uncertain signifance, and the two variants of the COL4A5 gene identified in Families Two and Three are pathogenic. The probands of Families Two and Three are diagnosed as Alport syndrome. The study suggests that clinicians should examine genetic variants of FH associated genes in families with hematuria when the probands were diagnosed as IgAN by their clinical manifestations, renal pathology and routine immunohistochemistry.

A multicenter study of reference intervals for 15 laboratory parameters in Chinese children / 中华儿科杂志

Objective@#To establish comprehensive laboratory reference intervals for Chinese children.@*Methods@#This was a cross-sectional multicenter study. From June 2013 to December 2014, eligible healthy children aged from 6-month to 17-year were enrolled from 20 medical centers with informed consent. They were assessed by physical examination, questionnaire survey and abdominal ultrasound for eligibility. Fasting blood samples were collected and delivered to central laboratory. Measurements of 15 clinical laboratory parameters were performed, including estradiol (E2), testosterone(T), luteinizing hormone(LH), follicle-stimulating hormone(FSH), alanine transaminase(ALT), serum creatinine(Scr), cystatin C, immunoglobulin A(IgA), immunoglobulin G(IgG), immunoglobulin M(IgM), complement (C3, C4), alkaline phosphatase(ALP), uric acid(UA) and creatine kinase(CK). Reference intervals were established according to central 95% confidence intervals for reference population, stratified by age and sex.@*Results@#In total, 2 259 children were enrolled. Finally, 1 648 children were eligible for this study, including 830 boys and 818 girls, at a mean age of 7.4 years. Age- and sex- specific reference intervals have been established for the parameters. Reference intervals of sex hormones increased gradually with age. Concentrations of ALT, cystatin C, ALP and CK were higher in children under 2 years old. Serum levels of sex hormones, creatinine, immunoglobin, CK, ALP and urea increased rapidly in adolescence, with significant sex difference. In addition, reference intervals were variable depending on assay methods. Concentrations of ALT detected by reagents with pyridoxal 5'-phosphate(PLP) were higher than those detected by reagents without PLP. Compared with enzymatic method, Jaffe assay always got higher results of serum creatinine, especially in children younger than 9 years old.@*Conclusion@#This study established age- and sex- specific reference intervals, for 15 clinical laboratory parameters based on defined healthy children.

Application of Eculizumab in children with atypical hemolytic uremic syndrome / 中华实用儿科临床杂志

Atypical hemolytic uremic syndrome (aHUS) is associated with a poorer prognosis,and an increased risk for end-stage renal disease (50％) or death (25％).There are about 50％ of patients with aHUS associated with dysfunctional complement regulation.Eculizumab,a monoclonal anti-C5 antibody,prevents C5 cleavage and the formation of C5a and C5b-9,thus inhibiting complement activation via 3 pathways and its terminal product formation.Therefore,it is applied to treat complement-mediated aHUS in children and its application improved the prognosis of aHUS.Eculizumab has been recommended as first-line treatment in children with complement-mediated aHUS by an international consensus.In this paper,the application of Eculizumab in children with atypical hemolytic uremic syndrome are reviewed briefly.

Diagnosis and treatment of renal glucosuria / 中华实用儿科临床杂志

Renal glycosuria (RG) is an inherited disorder due to defective reabsorption of glucose by the proximal renal tubular.It is attributed to the mutations in the SCL5A2 gene,encoding the sodium-glucose transporter 2 (SGLT2).A defect of SGLT2 is responsible for impaired reabsorption of the filtered glucose in the proximal renal tubular,termed S1,which leads to glycosuria.RG is characterized by normal fasting serum glucose concentration and persistent isolated glucosuria,identification of glucose as the urinary sugar.The inherited pattern of RG is co-dominant inheritance trait with incomplete penetrance.The diagnostic criteria of glycosurias are as follows:a constant and relatively stable urinary glycosurias (10-100 g/d),identification of glucose as the urinary sugar,normal concentration of fasting plasma glucose and normal oral glucose tolerance test,evidence that individuals have normal carbohydrates intake,storage and metabolism.RG does not require special treatment generally,but the advice concerns diet with increasing the intake of carbohydrates.Physical activity should be moderate and professional,and excesive muscle and exercise should be not advisable.

Analysis of variants in complement genes in Han Chinese children with atypical hemolytic uremic syndrome / 中华儿科杂志

Objective@#To investigate the prevalence and characteristics of pathogenic variants in complement genes in Han Chinese children with atypical hemolytic uremic syndrome (aHUS).@*Method@#Eleven Han Chinese children with aHUS, including 9 boys and 2 girls aged between 1 year and 4 months and 13 years, were investigated in Department of Pediatrics, Fuzhou General Hospital, from November 1998 to February 2014. Analysis of variants of all the exons of 10 complement genes (CFH, MCP, CFI, C3, CFB, CFHR1, CFHR2, CFHR3, CFHR4 and CFHR5), including 25 bases from 3′ end and 25 bases from 5' end, was performed in the 11 cases by targeted sequence capture and next generation sequencing. Significant variants detected by next generation sequencing were confirmed by Sanger sequencing. To understand pathogenicity of variants found in the captured genes, we investigated genetic conservation by multiple protein sequence alignment among different species, and analyzed whether the variants were located in protein domains or not, and investigated functional significance by functional computational prediction methods.@*Result@#Twenty-seven percent of Han Chinese children with aHUS carried pathogenic variants in the 10 complement genes. Pathogenic variant CFB 221G>A (R74H) was detected in Patient 3 and Patient 9, which was not found in parents of Patient 3′ , and was found in healthy father of patient 9. Pathogenic variant CFHR5 242C>T (P81L) was found in Patient 2, and was found in healthy father of patient 2. However, no pathogenic variants in genes CFH, MCP, CFI, C3, CFHR1, CFHR2, CFHR3 and CFHR4 were identified.@*Conclusion@#Pathogenic variants in the 10 complement genes were identified in 3/11 of Han Chinese children with aHUS in our study and CFB was the most frequently mutated gene.

Research progress of benign familial hematuria / 中华实用儿科临床杂志

Benign familial hematuria,also called thin basement membrane nephropathy,is caused by a heterozygous mutation in the COL4A3 or COL4A4 gene.The prognosis of the patients with benign familial hematuria,who present isolated hematuria without associated with proteinuria and normal renal function,is good in childhood.However,the prognosis of part of the patients with benign familial hematuria,who appear proteinuria,hypertension,chronic renal failure and end-stage kidney disease,is poor in adulthood.Therefore,the patients with benign familial hematuria should be carried on the long-term follow-up,and may be reviewed every 1-2 years for hypertension,proteinuria,and renal impairment.Treatment for benign familial hematuria should include an angiotensin converting enzyme inhibitor to delay the onset of renal failure.

Diagnosis of a boy with sporadic Alport syndrome using next generation sequencing and literature review / 中华实用儿科临床杂志

Objective To study the feasibility of testing three disease-causing genes for Alport syndrome,COL4A3,COL4A4 and COL4AS,in diagnosing patients with sporadic Alport syndrome by using targeted capture and next generation sequencing.Methods The clinical data of a 9-year-old boy suspected with Alport syndrome were collected.Genomic DNA was extracted using standard procedures from the peripheral blood leukocytes of the patient and his parents,respectively.Targeted capture and next generation sequencing and Sanger sequencing were applied to analyze the mutations in the 3 disease-causing genes.Clinical data of cases reported already with autosomal recessive Alport syndrome caused by the mutations in the COL4A4 gene were summarized.Results The patient was presented with neither family history of hematuria nor chronic renal failure.Haematuria and proteinuria were found at the age of 1 year.The patient presented with episodes of macrohaematuria and gradually developed nephrotic-level proteinuria.At the age of 8 years 7 months,bilateral sensorineural hearing loss was diagnosed.So a probable diagnosis of Alport syndrome was postulated.A compound heterozygous pathogenic mutations of 3578-1G ＞ A and 3967 C ＞ T(Q1323X) were identified in the COL4A4 gene in the patient.The mutation of 3578-1G ＞ A was inherited from his father,and the mutation of Q1323X from his mother.The patient was decisively diagnosed with autosomal recessive Alport syndrome.Conclusions The test of COL4A3,COL4A4 and COL4A5 genes can help diagnose patients with sporadic Alport syndrome by using targeted capture and next generation sequencing.

Mutational analysis of MYO1E in children with sporadic steroid-resistant nephrotic syndrome in Chinese Han ethnic group / 中华儿科杂志

<p><b>OBJECTIVE</b>Previous studies have demonstrated that two homozygous missense MYO1E mutations are associated with childhood autosomal recessive focal segmental glomerulosclerosis in steroid-resistant nephrotic syndrome (SRNS) families from Italy and Turkey. Non-disease-causing heterozygous MYO1E variants were also found in other SRNS patient cohorts. However, the role of MYO1E mutations in Chinese sporadic SRNS has not been established.</p><p><b>METHOD</b>Peripheral blood samples were collected for genetic analysis from 54 children with sporadic SRNS in Chinese Han ethnic group and a normal control group of 59 healthy adult volunteers. None of the patients carried mutations in NPHS2 or WT1. Genomic DNA was extracted from peripheral blood leukocytes. Twenty-eight exons and exon-intron boundaries of the MYO1E gene were amplified by polymerase chain reaction. Mutational analysis was performed by direct DNA sequencing and restriction endonuclease digestion.</p><p><b>RESULT</b>Fifty-one variants in the MYO1E gene were identified in 54 children with sporadic SRNS. Among them, 10 MYO1E mutations of IVS1-11T>C, IVS2-86T>A, 279T>C (D93D), IVS6-181G>A, 718C>T (L240F), 1678A>G (T560A), IVS16-35A>G, IVS18+48T>A, IVS19+38G>A and IVS25+13C>T were detected in 11 patients, whereas they were absent in the 59 normal Chinese controls. Forty-one variants in MYO1E were identified and all of them were published in single nucleotide polymorphism database from national center for biotechnology information. Furthermore, all the 10 MYO1E mutations were in heterozygous states.</p><p><b>CONCLUSION</b>MYO1E mutations are not a major cause of Chinese children with sporadic SRNS in the study.</p>

Steroid-resistant nephrotic syndrome and MYO1E mutation / 国际儿科学杂志

MYO1E gene is located on chromosome 15 and encodes myosin 1e,which acts as an actin-based molecular motor of cytoskeleton. Myosin 1e is critical to maintain the podocyte function and the conse-quent integrity of the glomerular filtration barrier. Mutations in MYO1E gene has been indentified to be the cause of childhood-onset,familial steroid-resistant focal segmental glomerulosclerosis. Surprisingly,three patients with MYO1E mutations had partial remission by cyclosporine therapy. Detection of the MYO1E gene in the patients suffering from steroid-resistant nephrotic syndrome will be beneficial to make therapeutic decisions and predict prognoses.

Mutational analysis of NPHS1 gene in children with sporadic steroid-resistant nephrotic syndrome in Southern Chinese Han ethnic group / 中华肾脏病杂志

Objective To elucidate the mutations of NPHS1 gene in children with sporadic steroid-resistant nephrotic syndrome (SRNS) in Southern Chinese Han ethnic group.Methods Peripheral blood samples were collected for genetic analysis from 40 patients with sporadic SRNS and 50 healthy volunteers as control.Genomic DNA was isolated from peripheral blood leucocytes.Twenty-nine exons and exon-intron boundaries of the NPHS1 gene were amplified by polymerase chain reaction.Mutational analysis was performed by DNA sequencing directly.Results Seven variants,928G＞A(D310N),2677A＞G (T893A),2869G＞C (V957L),IVS8+30C＞T,IVS21+14G＞A,IVS25-23C＞T and *142T＞C,of NPHS1 gene were found in 6 of 40 children with sporadic SRNS,whereas they were not found in 50 healthy controls.2677A ＞G,IVS8 +30C ＞T,IVS21 +14G＞A,IVS25-23C ＞T and *142T＞C were novel.Moreover,thirteen already reported NPHS1 polymorphisms,294C＞T,349G＞A,IVS3+15C＞T,IVS3+61A＞G,803G＞A,IVS8+68A＞G,1339G ＞A,1802G ＞C,2223C ＞T,2289C ＞T,IVS24 +36C ＞T,3315G＞A and IVS27 +45C ＞T,were detected in some patients and controls. Conclusions NPHS1 mutations in 6 of 40 children with sporadic SRNS in Southern Chinese Han ethnic group (15％) are detected.NPHS1 mutations are existed in Southern Chinese children,so it is necessary to perform the mutation analysis of NPHS1 gene in those children patients.

Mutational analysis of WT1 and PLCE1 in three Chinese families with steroid-resistant nephrotic syndrome / 中华肾脏病杂志

Objective To examine mutations in the WT1 and PLCE1 gene in three Chinese families with autosomal recessive steroid-resistant nephrotic syndrome (SRNS) once mutations in NPHS2 had been excluded. Methods Peripheral blood samples were collected for genetic analysis from three probands of three Chinese families and their parents, and two probands' siblings, and 50 adult volunteers with normal urinalysis. Genomic DNA was isolated from peripheral blood leucocytes. Ten exons and exon-intron boundaries of WT1, and 31 exons and exon-intron boundaries of PLCE1 were amplified by polymerase chain reaction (PCR). Mutational analysis was performed by DNA sequencing directly and RFLP (restriction fragment length polymorphism) and/or PCR. Results No mutation in both WT1 and PLCE1 was identified in three probands from three Chinese families with autosomal recessive SRNS. However, three variants of WT1, 126C>T, ⅣS5-64A>G and 903A>G, and 13 variants of PLCE1, -134A>G, 810T>C, 960G>A, ⅣS11-28C>G, ⅣS15+26A>C, 4724G>C, ⅣS20+40C>T, ⅣS21+64G>A, ⅣS22-26T> A, 5320C>T, 5780A>G, ⅣS27+24A>G and ⅣS31 +48_49insT, were detected in three probands and some controls, indicating that all these variants were gene polymorphisms. WT1 polymorphism ⅣS5-64A>G, and PLCE1 polymorphism ⅣS22-26T>A were novel. Conclusion All the encoding exons and exon-intron boundaries of both WT1 and PLCE1 in three probands are examined, and no causative mutations in WT1 and PLCE1 axe found, suggesting that mutation in WT1 and PLCE1 genes is not a major cause of the Chinese families with autosomal recessive SRNS.

The development and clinical applications of automatic negative pressure gun for biopsy / 中国医疗器械杂志

Using the new negative pressure biopsy technology, the automatic negative pressure gun and the specific puncture needle for the biopsy have been developed. Renal biopsies were conducted in 1136 cases, with the success rate being 99.9%, and 29 cases gross hematuria while the hepatic biopsies were conducted in 16 cases, mass biopsies in 3 cases with the success rates being 100% respectively. The biopsy gun has the advantages of easy manipulation, higher success rate and lower incidence of complications.