scholarly journals Case Report: The Monogenic Familial Steroid-Resistant Nephrotic Syndrome Caused by a Novel Missense Mutation of NPHS2 Gene A593C in a Chinese Family

2021 ◽  
Vol 9 ◽  
Author(s):  
Ling Bai ◽  
Jing Zhuang ◽  
Changrong Zhang ◽  
Chen Lu ◽  
Xuefei Tian ◽  
...  

Background: Pathogenic variants in the NPHS2 gene encoding podocin in kidney podocytes are associated with autosomal recessive steroid-resistant nephrotic syndrome (SRNS) by disrupting podocyte function and the integrity of the glomerular filtration barrier. The outcome is generally poor by progressing into end-stage kidney disease (ESKD). With the help of gene diagnostics, we can further understand the role of podocin of podocytes in the development and progression of SRNS. However, the pathological mutation of NPHS2 and clinical relevance remain further elusive.Case Presentation: Two siblings, a 15-year-old girl and her 10-year-old younger brother from a consanguineous Chinese family, presented with nephrotic syndrome. Both of them developed progressive proteinuria starting from the 5-year-old of age. The renal pathological lesions for them revealed focal segmental glomerulosclerosis (FSGS). There was no response to the glucocorticoid, calcineurin inhibitors, and rituximab treatment. The female affected patient received the hemodialysis treatment due to ESKD in June 2020; the male patient was still in follow-up presenting with SRNS. The mutational screening of the two patients and their parents using Trio whole-exome sequencing showed the NPHS2 gene de novo missense mutation in exon 5 (A593C), for which the two siblings were homozygous and their parents confirmed heterozygous asymptomatic carriers. No other SRNS-related gene variants with the SRNS were determined.Conclusion: Pathological gene variants screening in children clinically suspected with SRNS might be helpful in the diagnosis as well as appropriate decisions on treatment strategies and prediction of prognosis.

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Larisa Prikhodina ◽  
Svetlana Papizh ◽  
Inna Povolotskaya

Abstract Background and Aims Monogenic causes of steroid-resistant nephrotic syndrome (SRNS) have been reported for up to one-third of children depending on age of the disease onset. Immunosuppressive treatment of genetic SRNS with calcineurin inhibitors (CNIs) is still controversial. The aim of the study was to investigate the efficacy of CNIs with focus on inducing remission and long-term kidney function in children with monogenic SRNS. Method Retrospective analysis of efficacy CNIs in five children (2M/3F) with monogenic SRNS was performed. Kidney biopsy prior CNIs revealed FSGS (n=4) and MCD (n=1). The initial cyclosporine (CsA) dose was 5 mg/kg/24h to keep a target level of 80-150 ng/ml and tacrolimus (TAC) - 0.1 mg/kg/24h to achieve a target level of 5-10 ng/ml. CsA took all 5 patients with subsequent switching to TAC in 2 children due to cosmetic side effects. The median follow-up period was 165.0 (IQR: 59.0; 185.5) months. Next generation sequencing (NGS) was used for identification of pathogenic variants in all patients. Results The median age at onset of monogenic SRNS was 33.0 (IQR: 16.5; 63.0) months. 2/5 (40%) patients presented with acute SRNS, 1/5 (20%) child with infantile NS, 1/5 (20%) - with isolated nephrotic range proteinuria with hypoalbuminemia and 1/5 (20%) - with NS and extrarenal features of Nail-Patella syndrome. NGS identified previously described pathogenic variants in all 5 children, including NPHS2 homozygous c.28dup (p.Glu87Ter) (n=1), NPHS2 compound heterozygous c.868G>A (p.Val290Met) in combination with c.686G>A (p.Arg229Gln) (n=1), LMX1B heterozygous c.788T>G (p.Val263Gly) (n=1), LMX1B heterozygous c.737G>A (p.Arg246Gln) (n=1), and COL4A3 heterozygous c.2962G>A (p.Gly988Arg) variant (n=1). The median time from diagnosis to initiation of CNIs treatment was 72.0 (IQR: 33.0; 93.0) months. CNIs induced complete remission in 2/5 (40%) patients, presented with acute SRNS, including one girl with MCD due to NPHS2 compound heterozygous variants with mutation-dependent pathogenicity of one (p.R229Q) of them and one boy with FSGS due to COL4A3 heterozygous variant (n=1). Partial remission was induced by CNIs in 2/5 (40%) girls with FSGS due to LMX1B heterozygous variants with isolated SRNS (n=1) and Nail-Patella syndrome (n=1). The median duration of CNIs treatment to obtain complete or partial remission was 13.5 (IQR: 6.8; 15.8) months. Acute CNIs-associated nephrotoxicity had 2 patients with LMX1B variants. At the last follow up full and partial responders to CNIs treatment aged of 16.5 (IQR: 11.8; 17.5) years had CKD-1 (n=3) and CKD-2 (n=1). 1/5 (20%) boy with NPHS2-associated infantile NS was CNI resistant and developed CKD-5 at the age of 6.5 years with subsequent living related kidney transplantation. Conclusion We found that 4/5 (80%) children with monogenic SRNS demonstrated partial or full response to CNIs treatment with stable long-term kidney function. We assume that CNIs might improve podocyte function by stabilization of their cytoskeleton disrupted in patients with monogenic SRNS.


2019 ◽  
Vol 46 (6) ◽  
pp. 6339-6344
Author(s):  
Sepideh Zununi Vahed ◽  
Hakimeh Moghaddas Sani ◽  
Mehdi Haghi ◽  
Mohammadali Mohajel Shoja ◽  
Mohammadreza Ardalan

2021 ◽  
Vol 9 ◽  
Author(s):  
Ling Hou ◽  
Yue Du ◽  
Yubin Wu ◽  
Yue Zeng ◽  
Chengguang Zhao

Nail-patella syndrome (NPS) is a rare autosomal-dominant disorder characterized by the classic tetrad of absent or hypoplastic finger and toe nails, absent or hypoplastic patella, skeletal deformities involving the elbow joints, and iliac horns. This disease is caused by heterozygous pathogenic variations in the LMX1B gene, which encodes the LIM homeodomain transcription factor protein (LMX1B). We report a case of corneal leucoma and dysplasia prior to overt steroid-resistant nephrotic syndrome (SRNS) in a patient with NPS. At presentation, the parents of a 5-year-old female patient reported their daughter had corneal leucoma, psychomotor delay and speech defect. We also noted the presence of bilateral edema of the lower extremities, hypertension, nail dystrophy, and the bilateral absence of patella. She developed steroid-resistant nephrotic syndrome. Lowe oculocerebrorenal syndrome and NPS were the conditions considered in differential diagnosis. Trio-based whole genome sequencing indicated a heterozygous de novo likely pathogenic variation in the LMX1B gene (c.805A>C [p.Asn269His]). Patients with NPS often develop nail, ocular, or orthopedic symptoms prior to nephrotic syndrome. Corneal leucoma may be a novel clinical presentation of NPS.


2021 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Ahmedz WIdiasta ◽  
Kurnia Wahyudi ◽  
Husna Nugrahapraja ◽  
Yunia Sribudiani ◽  
Dedi Rachmadi

Background: Steroid-resistant nephrotic syndrome (SRNS) is a leading contributor to chronic kidney disease (CKD), and calcineurin inhibitors (CNIs) or monoclonal antibodies are currently the best identified therapy. Meanwhile, some developing countries still use alkylating agents (AA) such as cyclophosphamide (CPA) to treat SRNS due to economic reasons. Objectives: This study aims to determine the employability of soluble urokinase plasminogen activator receptor (suPAR) as a biomarker for monitoring therapy in SRNS children and compare the clinical improvement with those treated with an AA and CNIs. Methods: This was a retrospective cohort study conducted at Hasan Sadikin Hospital, Indonesia. The data was collected from July 2019 to July 2020 from 70 children with FSGS. Clinical signs were evaluated monthly, and serum suPAR level was measured at the third and sixth months following therapy. Two-way repeated measures ANOVA was carried out to compare the differences in suPAR level at baseline with the third and sixth months in SRNS patients who received AA and CNIs. Results: The mean age was nearly similar between the two groups based on the t-test (P = 0.140). Steroid-resistant nephrotic syndrome was more frequent in boys than in girls (P = 0.020), according to the Chi-square test. Baseline serum suPAR level was not significantly different between the two groups. In the third month, the daily urinary protein level was higher in SRNS patients that received the AA compared to the CNIs group (P < 0.001). There was a significant interaction between time and treatment (F(2,138) = 7.203, P = 0.001), with higher suPAR level in SRNS patients that received the AA compared to those administered with CNIs at the 3rd and 6th months, but this difference was not statistically significant (P > 0.05). Conclusions: As a noninvasive tool, suPAR is a promising modality in monitoring SRNS therapy, and CNIs have a tendency to achieve faster remission than the AA.


2015 ◽  
Vol 8 (4) ◽  
pp. 136 ◽  
Author(s):  
Syed Raza Shah ◽  
Areeba Altaf ◽  
Mohammad Hussham Arshad ◽  
Anum Mari ◽  
Sahir Noorani ◽  
...  

<p>A chronic, progressive disorder Steroid Resistant Nephrotic Syndrome (SRNS) accounts for 10-20% of all children with Nephrotic Syndrome. It is a heterogeneous disorder comprised of persistent edema, proteinuria, hypoalbuminemia and hyperlipidemia. Treatment for steroid-resistant nephrotic syndrome (SRNS) is challenging and children who suffer from SRNS require aggressive treatment to achieve remission. Calcineurin inhibitors have been used more in an empirical manner than on the basis of clear rationale. It was in 1984 when cyclosporine was first considered for the treatment of steroid resistant nephrotic syndrome. Cyclosporin is a calcineurin inhibitor that suppresses immune response by downregulating the transcription of various cytokine genes. Till now many studies have been conducted to determine dosages, duration of therapy, side effects and advantages of cyclosporine. Treatment of SRNS remains a difficult challenge in pediatric nephrology.  Treatment should be individualized according to the underlying histopathology, and clinical and environmental conditions of the children. There is an urgent need to distinguish as soon as possible those patients who may benefit from prolonged immunosuppressive treatment from those who will not benefit from such treatment and who will just suffer from its major side effects. The emerging evidence that the majority of genetic forms of SRNS should receive symptomatic treatment only, should also be clinically tested and studies baring its significance should be evaluated in the future.</p>


2019 ◽  
Vol 8 (4) ◽  
pp. 271-282 ◽  
Author(s):  
Sepideh Zununi Vahed ◽  
Hakimeh Moghaddas Sani ◽  
Sima Rajabzadeh ◽  
Ziba Nariman-Saleh-Fam ◽  
Mina Hejazian ◽  
...  

Steroid-resistant nephrotic syndrome (SRNS) is a challenging clinical task. It has heterogeneous etiology and extremely variable clinical outcomes and generally progresses to end-stage renal disease (ESRD). Different gene mutations in podocyte’s slit diaphragm, mitochondria, and cytoskeleton proteins, as well as glomerular basement membrane (GBM) have been associated with SRNS. These proteins regulate the function of the glomerular filtration barrier. Advances in genetic approaches and podocytology have led to discover the SRNS-causing genes that lead to a better understanding of the drug resistance. More than 45 genetic mutations have been recognized in the hereditary form of SRNS. This review offers an update on the current knowledge of steroid resistance-causing gene mutations in podocytes. Understanding the specific genes involved in SRNS would guarantee an optimum therapeutic benefit of steroid treatment.


Meta Gene ◽  
2021 ◽  
pp. 101004
Author(s):  
Glory S. Parmar ◽  
Jinal M. Thakor ◽  
Kinnari N. Mistry ◽  
Sishir Gang ◽  
Dharamshibhai N. Rank ◽  
...  

2018 ◽  
Vol 54 (01) ◽  
pp. 043-053
Author(s):  
Arvind Bagga

AbstractNephrotic syndrome is an important chronic disease of childhood, with a steroid sensitive course in most patients. Research on pathogenesis has emphasized the importance of T-lymphocyte dysregulation and vascular permeability factors that alter podocyte function and glomerular permselectivity. Mutations in genes that encode important podocyte proteins and therapeutic targets within podocytes have been identified. A hypothesis unifying available evidence on pathogenesis is yet to be proposed. An important proportion of patients have difficult disease course, characterized by frequent relapses, steroid dependence or steroid resistance, requiring therapy with alternative immunosuppressive agents. Clinical studies support the use of levamisole, cyclophosphamide, mycophenolate mofetil, calcineurin inhibitors (CNIs) and rituximab in patients with frequent relapses or steroid dependence. The management of steroid-resistant nephrotic syndrome is difficult and patients failing to achieve remission show progressive renal damage. Prospective studies in patients with steroid sensitive and steroid resistant nephrotic syndrome are the basis of current guidelines while ongoing studies will help identify and formulate effective and safe therapies.


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