BACKGROUND: Genetic focal segmental glomerulosclerosis (FSGS) is caused by pathogenic variants in a broad spectrum of genes that have a variable representation based on subjects' ethnicity and/or age. The most frequently mutated autosomal recessive gene in FSGS is NPHS2. In this study, we analyzed the spectrum of NPHS2 variants and their associated phenotype in Czech adult FSGS patients. METHODS: A representative cohort of 234 adult patients with FSGS, derived from 225 families originating from all regions of Czechia, was analyzed by massively parallel sequencing. In this study, we focused on the comprehensive analysis of the NPHS2 gene. The histological classification of FSGS followed the Columbia classification. RESULTS: We detected seven (3%) cases bearing homozygous or compound heterozygous pathogenic NPHS2 variants. A single pathogenic variant c.868G > A (p.Val290Met) was found in the majority of NPHS2-positive cases (86%; 6 out of 7) in histologically confirmed instances of FSGS. Its allele frequency among unrelated NPHS2-associated FSGS patients was 50% (6/12), and Haplotype analysis predicted its origin to be a result of a founder effect. There is an identical V290M-related haplotype on all V290M alleles spanning a 0,7 Mb region flanking NPHS2 in Central European FSGS populations. The phenotype of the p.Val290Met NPHS2-associated FSGS demonstrated a later onset and a much milder course of the disease compared to other NPHS2 pathogenic variants associated with FSGS. The mean age of the FSGS diagnosis based on kidney biopsy evaluation was 31.2 ± 7.46 years. In 50% of all cases, the initial disease manifestation of proteinuria occurred only in adulthood, with 83% of these cases not presenting with edemas. One-third (33%) of the studied subjects progressed to ESRD (2 out of 6) at the mean age of 35.0 ± 2.82 years. CONCLUSIONS: We identified the most prevalent pathogenic variant, p.Val290Met, in the NPHS2 gene among Czech adult FSGS patients, which has arisen due to a founder effect in Central Europe. The documented milder course of the disease associated with this variant leads to the underdiagnosis in childhood. We established the histopathological features of the NPHS2-associated adult FSGS cases based on the Columbia classification. This might improve patient stratification and optimize their treatment.

• Publication type
• Journal Article MeSH

BACKGROUND: Management of children with congenital nephrotic syndrome (CNS) is challenging. Bilateral nephrectomies followed by dialysis and transplantation are practiced in most centres, but conservative treatment may also be effective. METHODS: We conducted a 6-year review across members of the European Society for Paediatric Nephrology Dialysis Working Group to compare management strategies and their outcomes in children with CNS. RESULTS: Eighty children (50% male) across 17 tertiary nephrology units in Europe were included (mutations in NPHS1, n = 55; NPHS2, n = 1; WT1, n = 9; others, n = 15). Excluding patients with mutations in WT1, antiproteinuric treatment was given in 42 (59%) with an increase in S-albumin in 70% by median 6 (interquartile range: 3-8) g/L (P < 0.001). Following unilateral nephrectomy, S-albumin increased by 4 (1-8) g/L (P = 0.03) with a reduction in albumin infusion dose by 5 (2-9) g/kg/week (P = 0.02). Median age at bilateral nephrectomies (n = 29) was 9 (7-16) months. Outcomes were compared between two groups of NPHS1 patients: those who underwent bilateral nephrectomies (n = 25) versus those on conservative management (n = 17). The number of septic or thrombotic episodes and growth were comparable between the groups. The response to antiproteinuric treatment, as well as renal and patient survival, was independent of NPHS1 mutation type. At final follow-up (median age 34 months) 20 (80%) children in the nephrectomy group were transplanted and 1 died. In the conservative group, 9 (53%) remained without dialysis, 4 (24%; P < 0.001) were transplanted and 2 died. CONCLUSION: An individualized, stepwise approach with prolonged conservative management may be a reasonable alternative to early bilateral nephrectomies and dialysis in children with CNS and NPHS1 mutations. Further prospective studies are needed to define indications for unilateral nephrectomy.

• MeSH
• Albumins therapeutic use   MeSH
• Child MeSH
• Infant MeSH
• Humans MeSH
• Membrane Proteins genetics   MeSH
• Mutation MeSH
• Nephrectomy * MeSH
• Nephrology methods   MeSH
• Nephrotic Syndrome genetics   surgery   therapy   MeSH
• Pediatrics methods   MeSH
• Child, Preschool MeSH
• Prospective Studies MeSH
• Proteinuria therapy   MeSH
• Retrospective Studies MeSH
• Sepsis complications   MeSH
• Thrombosis complications   MeSH
• Check Tag
• Child MeSH
• Infant MeSH
• Humans MeSH
• Male MeSH
• Child, Preschool MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Multicenter Study MeSH
• Geographicals
• Europe MeSH

• Publication type
• Meeting Abstract MeSH

BACKGROUND: Steroid-resistant nephrotic syndrome (SRNS) has a heterogeneous spectrum of monogenic causes that substantially differ among populations. The aim of this study was to analyse the genetic aetiology of SRNS in Czech and Slovak paediatric patients. METHODS: We analysed clinical data from 74 patients (38 boys) with congenital (15%), infant (14%), and childhood-onset (71%) SRNS collected from the Czech Republic and Slovakia from 2000 to 2017 (inclusive). The DNA samples were first analysed by Sanger sequencing (genes NPHS2, NPHS1, and WT1) and then by next generation sequencing (NGS) using a targeted panel of 48 genes previously associated with SRNS. Family segregation of the causative variants was confirmed by Sanger sequencing when possible. RESULTS: Genetic diagnosis was established in 28/74 patients (38%) based on findings of pathogenic or likely pathogenic causative variants in genotypes conforming to the expected mode of inheritance. Sanger sequencing diagnosed 26% of patients, whereas second-tier testing by a targeted NGS panel diagnosed a further 12%. Frequent causative genes were NPHS2 (15%), WT1 (9.5%), and surprisingly NUP93 with four (5.4%) unrelated cases. Additional causative genes included COQ2 (two patients), NPHS1, INF2, DGKE, and LMX1B (one patient each). CONCLUSIONS: Compared with outright use of NGS, our tiered genetic testing strategy was considerably more rapid and marginally less expensive. Apart from a high aetiological fraction of NPHS2 and WT1 genes, our study has identified an unexpectedly high frequency of a limited set of presumably ancestral causative mutations in NUP93. The results may aid in tailoring testing strategies in Central European populations.

• MeSH
• Child MeSH
• Genetic Predisposition to Disease * MeSH
• Genetic Testing MeSH
• Genotype MeSH
• Intracellular Signaling Peptides and Proteins genetics   MeSH
• Infant MeSH
• Nuclear Pore Complex Proteins genetics   MeSH
• Humans MeSH
• Longitudinal Studies MeSH
• Membrane Proteins genetics   MeSH
• Adolescent MeSH
• Mutation MeSH
• DNA Mutational Analysis MeSH
• Nephrotic Syndrome genetics   MeSH
• Infant, Newborn MeSH
• Child, Preschool MeSH
• Prospective Studies MeSH
• WT1 Proteins genetics   MeSH
• Check Tag
• Child MeSH
• Infant MeSH
• Humans MeSH
• Adolescent MeSH
• Male MeSH
• Infant, Newborn MeSH
• Child, Preschool MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic MeSH
• Slovakia MeSH

Cíl: Cílem této studie bylo ověřit použitelnost poměru expresí genů NPHS2 a SYNPO při diagnostice fokální segmentální glomerulosklerózy (FSGS) a minimálních změn glomerulů (MCD) u českých pacientů a zároveň identifikovat nové markery, které by mohly vést k jednoznačnému rozlišení mezi oběma diagnózami. Typ studie: Pilotní studie Materiál a metody: Do studie bylo zařazeno 24 vzorků od pacientů s FSGS a MCD. Exprese genů byla stanovena metodou relativní kvantitativní real-time PCR provedené na kartách TaqMan ® Array Micro Fluidic Cards s následnou normalizací dat k referenčnímu genu GAPDH . Výsledky a závěry: Nebyly prokázány žádné statisticky významné rozdíly v expresi studovaných genů mezi pacienty s FSGS a MCD. Zároveň se nepodařilo potvrdit použitelnost poměru expresí genů NPHS2 a SYNPO pro rozlišení FSGS a MCD u českých pacientů.

Objective: The aim of this study was the verification of the applicability of NPHS2 / SYNPO ratio for diagnosis of focal seg - mental glomerulosclerosis (FSGS) and minimal change disease (MCD) in Czech patients and identification of new markers for distinguishing between MCD and FSGS. Material and methods: Our study was performed on 24 samples from patients with FSGS and MCD. Gene expressions were determined using relative quantitative real-time PCR and TaqMan ® Array Micro Fluidic Cards and normalized to the reference gene GAPDH . Results and conclusion: Our results did not find any significant difference in the podocin/synaptopodin ratio and in any other studied genes between FSGS and MCD.

• MeSH
• Gene Expression MeSH
• Glomerulosclerosis, Focal Segmental * diagnosis   MeSH
• Real-Time Polymerase Chain Reaction MeSH
• Humans MeSH
• Nephrosis, Lipoid * diagnosis   MeSH
• Pilot Projects MeSH
• Check Tag
• Humans MeSH

Kongenitálne nefrotické syndrómy (CNS) tvoria závažnú skupinu dedičných nefropatií. Primárny CNS tvorí CNS fínskeho typu, fokálnu segmentovú glomerulosklerózu/difúznu mezangiovú sklerózu, iné nesyndrómové formy CNS, ale zodpovedá aj za časť prípadov idiopatického NS. V práci sa uvádza prehľad doteraz známych génov a ich produktov, ktoré spôsobujú CNS. Kongenitálny NS fínskeho typu je najčastejšia forma dedičného NS, ktorá sa manifestuje už v prvom roku života, génom je NPHS1 na chromozóme 19q13.1, kóduje bielkovinu nefrín vo filtračnej štrbinovej membráne. Fokálnu segmentovú glomerulosklerózu (FSGS), resp. difúznu mezangiovú sklerózu (DMS) charakterizuje rezistencia na kortikoidy a imunosupresíva, génom je NPHS2, ktorý kóduje podocín. Autori uvádzajú charakteristiku ďalších 4 nesyndrómových foriem génových porúch, rozoberajú klinickú, laboratórnu a prenatálnu diagnostiku CNS a zvlášť zdôrazňujú význam genetického vyšetrenia a jeho klinického využitia. Terapia CNS je symptomatická, transplantácia obličky má pomerne dobré výsledky, ale prognóza ostáva závažná.

Congenital nephrotic syndromes (CNS) are important group of the hereditary nephropathies. Primary CNS constitutes Finnish type CNS, focal segmental glomerulosclerosis/diffuse mesangial sclerosis and other non-syndrome CNS forms, but a part of idiopathic NS cases, too. In the article is a review nowadays known genes and their products which cause CNS. Finnish type CNS is most frequent form of the hereditary NS manifested in first year of life, gen is NPHS1 on chromosome 19q13.1, codes a protein nephrin in the filtration membrane. Focal segmental glomerulosclerosis (FSGS) or diffuse mesangial sclerosis (DMS) are characterized with resistance on steroids and immunosuppressant’s, gen is NPHS2 which codes podocine. Authors characterize others 4 non-syndrome forms of the gens disorders, analyze clinical, laboratory and prenatal CNS diagnostics and stress importance of the genetic tests and their clinical use. CNS therapy is symptomatic, kidney transplantation has relatively good results, but prognosis is serious.

Congenital nephrotic syndrome (CNS) is a heterogeneous group of diseases with different causes and prognoses. Two thirds of cases of NS in the first year of life are caused by mutations in four genes (NPHS1, NPHS2, WT1, and LAMB2). The mutation of WT1 gene can lead to Denys-Drash syndrome (DDS). We report on female monozygotic twins with CNS presenting at 7 and 8 weeks of age with anuric renal failure. Both twins were treated by peritoneal dialysis. Renal biopsy proved diffuse mesangial sclerosis. Genetic analysis detected a new heterozygote WT1 mutation R434P in both twins. One child developed a unilateral nephroblastoma. Both twins died because of complications of CNS (sepsis and extensive thrombosis of central venous system/sepsis and sudden heart failure) at ages 23 weeks/13.5 months, respectively. DNA analysis showed the same WT1 mutation in the father, who showed at his age of 41 years no clinical consequences of this mutation and no signs of DDS. In conclusion, we report the third family with monozygotic twins with DDS due to WT1 mutation. The DDS has very rapidly led to end-stage renal failure and death in both twins which is in striking contrast to the manifestation in their father.

• MeSH
• Twins, Monozygotic MeSH
• Fatal Outcome MeSH
• Genes, Wilms Tumor MeSH
• Heterozygote MeSH
• Infant MeSH
• Humans MeSH
• Mutation, Missense MeSH
• Nephrotic Syndrome congenital   diagnosis   genetics   MeSH
• Diseases in Twins congenital   diagnosis   genetics   MeSH
• Check Tag
• Infant MeSH
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH
• Research Support, Non-U.S. Gov't MeSH

Anotace I: Nefrotický syndrom je závažný klinický stav vyznačující se především proteinurií, jehož podkladem jsou nejčastěji minimální změny glomerulů (MCN), fokální a segmentální glomeruloskleróza (FSGS), membranózní nefropatie (MGN) a IgA glomerulonefritida (IGAN). Anotace II: U dospělých nemocných s FSGS rezistentních na imunosupresi byly nejčastěji stanoveny mutace v následujících 3 genech: NPHS2, ACTN4 a TRPC6. Zjištění mutací může ovlivnit terapeutický postup. Anotace III: Cílem projektu je mutační analýza ve zmíněných genech u dospělých pacientů s histologicky ověřenou diagnózou FSGS/MCN. Tito pacienti jsou většinou resistentní k imunosupresivní terapii, ale po transplantaci ledviny NS nerelabuje. Anotace IV: Stanovení vlivu polymorfismů ve výšepopsaných genů a jejich promotorech umožní stanovení dalších prognostických faktorů vybraných glomerulonefritid (MCN, FSGS, MGN, IGAN).; Nephrotic syndrome (NS) is a serious condition characterized by massive proteinuria which is most frequently caused by minimal change disease (MCD), focal and segmental glomerulosclerosis (FSGS), membranous glomerulonephritis (MGN) and IgA nephropathy (IGAN). In adult patients with MCD/FSGS the most frequent genetic abnormality observed was the mutation in one of the 3 following genes : NPHS1, ACTN4 and TRPC6. Determination of gene mutations can influence the management and treatment. Aim of the proposal is the mutational analysis of the above mentioned genes in the patients with histologically proven diagnosis of MCD/FSGS. These patients are frequently resistant to immunosupressive therapy but do not recur after renal transplantation. The following part of the grant project is the determination of the significance of the genetic polymorphisms in the three mentioned genes and in their promotors on the progression of selected glomerulonephritidis (MCD, FSGS, MGN, IGAN).

• MeSH
• Actinin genetics   MeSH
• Glomerulosclerosis, Focal Segmental MeSH
• Glomerulonephritis, IGA MeSH
• Intracellular Signaling Peptides and Proteins genetics   MeSH
• Glomerulonephritis, Membranous MeSH
• Mutation MeSH
• Nephrotic Syndrome MeSH
• Polymorphism, Genetic MeSH
• Proteinuria MeSH
• Suppression, Genetic MeSH
• Calcium Channels MeSH

• Conspectus
• Biochemie. Molekulární biologie. Biofyzika
• NML Fields
• nefrologie
• biologie
• NML Publication type
• závěrečné zprávy o řešení grantu IGA MZ ČR

Focal segmental glomerulosclerosis and minimal change disease represent frequent histological patterns of renal injury in patients with nephrotic syndrome. Few cases carrying NPHS2 gene variants have been described to date. Mutational analysis of the NPHS2 gene was performed in 50 Czech adult patients with histologically proved FSGS/MCD. The common p.P20L and p.R229Q polymorphisms of the NPHS2 gene were tested in 169 patients with IgA nephropathy and in 300 individuals of the control group. No mutation in the NPHS2 gene in patients with adult onset was identified. One homozygous mutation p.V290M in a patient with onset in early childhood was found. One new heterozygous variant in the non-conservative area of the NPHS2 gene, p.G97S, was identified in a patient with childhoodonset FSGS. In one adult patient, there were two polymorphisms, p.P20L and p.R229Q, in trans-heterozygous state, which could contribute to steroid-resistant nephrotic syndrome. The most common polymorphism p.R229Q was identified in 12 % of FSGS/ MCD patients, in 11.8 % of IGAN patients and in 10% of controls. The heterozygosity of p.R229Q polymorphism was similar in the IGAN group, with non-significantly higher prevalence in IGAN patients with progressive form of the disease (15.9 % versus 9.4 %). The prevalence of p.P20L polymorphism was not significantly different among the groups (6 % in FSGS patients, 1.8 % in IGAN patients, 1 % in the control group). To conclude, NPHS2 mutations are rare in patients with adult onset of FSGS/MCD. The R229Q polymorphism is frequent in the Czech population and probably could have some influence on IGAN.

• MeSH
• Adult MeSH
• Genetic Predisposition to Disease genetics   MeSH
• Homozygote MeSH
• Glomerulonephritis, IGA genetics   MeSH
• Intracellular Signaling Peptides and Proteins genetics   MeSH
• Middle Aged MeSH
• Humans MeSH
• Membrane Proteins biosynthesis   genetics   MeSH
• Mutation MeSH
• DNA Mutational Analysis methods   MeSH
• Nephrotic Syndrome immunology   MeSH
• Polymorphism, Genetic MeSH
• Prevalence MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic MeSH

• Publication type
• Meeting Abstract MeSH