Infants with congenital nephrotic syndrome have comparable outcomes to infants with other renal diseases

The clinical characteristics of patients with congenital nephrotic syndrome secondary to NPHS1 mutation: Is nephrectomy still a therapeutic option for selected cases?

BACKGROUND

Managing congenital nephrotic syndrome (CNS) remains a clinical challenge. While albumin infusions and nephrectomy have been long-standing treatments, a conservative approach is increasingly favored. This study aimed to compare clinical outcomes between nephrectomy (Nx) and non-Nx in patients with bi-allelic NPHS1 mutations.

METHODS

This retrospective cohort study included 29 pediatric CNS patients (15 female, 14 male) with confirmed NPHS1 mutations. Clinical parameters including albumin infusion requirements, infections, hospitalizations, growth, and survival rates were analyzed in the Nx and non-Nx groups.

RESULTS

The median age at the time CNS was diagnosed was 29 days (IQR: 11-62 days). In all, 24 patients (82.8%) had homozygous NPHS1 mutations and 5 (17.2%) had compound heterozygous NPHS1 mutations. None of the patients had Fin-major mutation (i.e., p. Leu41 Aspfs*50). Unilateral/bilateral nephrectomy was performed in 16 patients. At 12 months post-nephrectomy the number of albumin infusions required, infections, and hospitalizations decreased significantly in the Nx group, as compared to the pre-nephrectomy period (p = 0.001, p = 0.027, and p = 0.004, respectively). Among the 13 (44.8%) patients in the non-Nx group, at 12 months after CNS was diagnosed the number of serum albumin infusions required significantly decreased (p = 0.007); however, the number of infections and hospitalization did not differ significantly (p = 0.589 and p = 0.5, respectively). Receiver operating characteristic (ROC) analysis showed that requiring albumin infusions ≥ 14 days/month predicted the decision to perform nephrectomy with 68% accuracy (73% sensitivity and 62% specificity).

CONCLUSIONS

Nephrectomy reduces albumin infusions, infections, and hospitalizations, suggesting it may be a beneficial treatment for selected CNS patients with NPHS1 mutations.

Whole-exome sequencing of a multicenter cohort identifies genetic changes associated with clinical phenotypes in pediatric nephrotic syndrome

Understanding the association between the genetic and clinical phenotypes in children with nephrotic syndrome (NS) of different etiologies is critical for early clinical guidance. We employed whole-exome sequencing (WES) to detect monogenic causes of NS in a multicenter cohort of 637 patients. In this study, a genetic cause was identified in 30.0% of the idiopathic steroid-resistant nephrotic syndrome (SRNS) patients. Other than congenital nephrotic syndrome (CNS), there were no significant differences in the incidence of monogenic diseases based on the age at manifestation. Causative mutations were detected in 39.5% of patients with focal segmental glomerulosclerosis (FSGS) and 9.2% of those with minimal change disease (MCD). In terms of the patterns in patients with different types of steroid resistance, a single gene mutation was identified in 34.8% of patients with primary resistance, 2.9% with secondary resistance, and 71.4% of children with multidrug resistance. Among the various intensified immunosuppressive therapies, tacrolimus (TAC) showed the highest response rate, with 49.7% of idiopathic SRNS patients achieving complete remission. Idiopathic SRNS patients with monogenic disease showed a similar multidrug resistance pattern, and only 31.4% of patients with monogenic disease achieved a partial remission on TAC. During an average 4.1-year follow-up, 21.4% of idiopathic SRNS patients with monogenic disease progressed to end-stage renal disease (ESRD). Collectively, this study provides evidence that genetic testing is necessary for presumed steroid-resistant and idiopathic SRNS patients, especially those with primary and/or multidrug resistance.

Clinical presentation and management of nephrotic syndrome in the first year of life: A report from the Pediatric Nephrology Research Consortium

BACKGROUND AND OBJECTIVES

Nephrotic syndrome (NS) in the first year of life is called congenital (CNS) if diagnosed between 0-3 months, or infantile (INS) if diagnosed between 3-12 months of age. The aim of this study was to determine if there were clinically meaningful differences between CNS and INS patients, regarding clinical presentation, management and outcomes.

DESIGN SETTING PARTICIPANTS AND MEASUREMENTS

Eleven Pediatric Nephrology Research Consortium sites participated in the study, using IRB-approved retrospective chart reviews of CNS and INS patients born between 1998 and 2019. Data were collected on patient characteristics, pertinent laboratory tests, provided therapy, timing of unilateral/bilateral nephrectomy and initiation of renal replacement therapy (RRT).

RESULTS

The study included 69 patients, 49 with CNS and 20 with INS, with a median age at diagnosis of 1 and 6 months, respectively. Management for the two groups was similar regarding nutrition, thyroxin supplementation, immunoglobulin administration, and thrombosis prophylaxis. Within the first 2 months after diagnosis, daily albumin infusions were used more often in CNS vs. INS patients (79 vs. 30%; p = 0.006), while weekly infusions were more common in INS patients (INS vs. CNS: 50 vs. 3%; p = 0.001). During the 6 months preceding RRT, albumin infusions were more frequently prescribed in CNS vs. INS (51 vs. 15%; p = 0.007). Nephrectomy was performed more often in CNS (78%) than in INS (50%; p = 0.02). End-stage kidney disease tended to be more common in children with CNS (80%) vs. INS (60%; p = 0.09).

CONCLUSION

Compared to INS, patients with CNS had a more severe disease course, requiring more frequent albumin infusions, and earlier nephrectomy and RRT. Despite center-specific variations in patient care, 20-40% of these patients did not require nephrectomy or RRT.

Congenital nephrotic syndrome

Congenital nephrotic syndrome (CNS), a challenging form of nephrotic syndrome, is characterized by massive proteinuria, hypoalbuminemia, and edema. Extensive leakage of plasma proteins is the main feature of CNS. Patients can be diagnosed in utero or during the first few weeks of life, usually before three months. The etiology of CNS can be related to either genetic or nongenetic etiologies. Pathogenic variants in NPHS1, NPHS2, LAMB2, WT1, and PLCE1 genes have been implicated in this disease. The clinical course is complicated by significant edema, infections, thrombosis, hypothyroidism, failure to thrive, and others. Obtaining vascular access, frequent intravenous albumin infusions, diuretic use, infection prevention, and nutritional support are the mainstay management during their first month of life. The best therapy for these patients is kidney transplantation. CNS diagnosis and treatment continue to be a challenge for clinicians. This review increases the awareness about the pathogenesis, diagnosis, and management of CNS patients.

Peritoneal dialysis outcomes in patients with nephrotic syndrome: a propensity score-matched cohort study

INTRODUCTION

It is unclear whether patients with end-stage renal disease (ESRD) and nephrotic syndrome (NS) can be treated with peritoneal dialysis (PD).

OBJECTIVES

To investigate the outcomes of PD treatment in ESRD patients with or without NS.

METHODS

In this retrospective cohort study, all incident patients with ESRD and NS who started PD from 1 February 2006 to 31 December 2017, were matched with patients without NS using propensity scores based on age, sex, diabetes mellitus status, and serum albumin.

RESULTS

Fifty-three patients in the NS PD group and 53 matched controls were included. The median survival of the NS PD group was comparable to that of the non-NS PD group. An interaction effect was observed between survival time and baseline NS status. Thus, patients' outcomes within and after 1.5 years were analyzed separately. Both mortality (log-rank test, p= .235) and technique failure (log-rank test, p= .543) rates within 1.5 years in patients with NS were comparable to those of the non-NS group. After 1.5 years, however, the NS status at baseline was associated with lower all-cause mortality (p= .020) and lower technique failure (p= .008) rates in PD patients compared with the non-NS group. The multivariable Cox regression analysis showed that compared with the patients in the non-NS PD group, PD patients with NS had both significantly lower all-cause mortality and lower technique failure rate after adjusting for other factors.

CONCLUSIONS

Our study indicates that PD may be considered as a long-term renal replacement therapy for patients with ESRD and baseline NS.

Pediatric Nephrotic Syndrome: Pharmacologic and Nutrition Management

Nephrotic syndrome is a common kidney disease during childhood that is characterized by alterations in glomerular filtration and leads to protein, fluid, and nutrient loss in the urine. Most patients experience peripheral, gravity-dependent edema; however, serious cases exhibit anasarca and ascites. Many long-term complications of the disease exist due to the underlying pathology and the therapies used for treatment, including metabolic bone disease, micronutrient deficiencies, and hyperlipidemia. Pharmacologic and nutrition interventions are key to appropriate management. Fluid and sodium restriction in combination with corticosteroids, albumin, and diuretics are used to manage edema. Steroid-sparing therapies like alkylating agents and calcineurin inhibitors and dietary modification to eliminate dairy and gluten may be warranted in patients with frequent relapses or steroid-refractory disease. Nutrition clinicians should familiarize themselves with the nuances of treating this disease to optimize care for children with nephrotic syndrome.

Management of congenital nephrotic syndrome: consensus recommendations of the ERKNet-ESPN Working Group

Congenital nephrotic syndrome (CNS) is a heterogeneous group of disorders characterized by nephrotic-range proteinuria, hypoalbuminaemia and oedema, which manifest in utero or during the first 3 months of life. The main cause of CNS is genetic defects in podocytes; however, it can also be caused, in rare cases, by congenital infections or maternal allo-immune disease. Management of CNS is very challenging because patients are prone to severe complications, such as haemodynamic compromise, infections, thromboses, impaired growth and kidney failure. In this consensus statement, experts from the European Reference Network for Kidney Diseases (ERKNet) and the European Society for Paediatric Nephrology (ESPN) summarize the current evidence and present recommendations for the management of CNS, including the use of renin-angiotensin system inhibitors, diuretics, anticoagulation and infection prophylaxis. Therapeutic management should be adapted to the clinical severity of the condition with the aim of maintaining intravascular euvolaemia and adequate nutrition, while preventing complications and preserving central and peripheral vessels. We do not recommend performing routine early nephrectomies but suggest that they are considered in patients with severe complications despite optimal conservative treatment, and before transplantation in patients with persisting nephrotic syndrome and/or a WT1-dominant pathogenic variant.

Autoimmunity in Focal Segmental Glomerulosclerosis: A Long-Standing Yet Elusive Association

Focal segmental glomerulosclerosis (FSGS) is a histological term that describes a pathologic renal entity affecting both adults and children, with a wide array of possible underlying etiologies. Podocyte damage with scarring, the hallmark of this condition, leads to altered permeability of the glomerular barrier, which may result in massive proteinuria and relentless renal function deterioration. A definite cause of focal segmental glomerulosclerosis can be confirmed in a minority of cases, while most forms have been traditionally labeled as primary or idiopathic. Despite this definition, increasing evidence indicates that primary forms are a heterogenous group rather than a single disease entity: several circulating factors that may affect glomerular permeability have been proposed as potential culprits, and both humoral and cellular immunity have been implicated in the pathogenesis of the disease. Consistently, immunosuppressive drugs are considered as the cornerstone of treatment for primary focal segmental glomerulosclerosis, but response to these agents and long-term outcomes are highly variable. In this review we provide a summary of historical and recent advances on the pathogenesis of primary focal segmental glomerulosclerosis, focusing on implications for its differential diagnosis and treatment.

Congenital nephrotic syndrome: is early aggressive treatment needed?-No

The management of infants with congenital nephrotic syndrome (CNS) is very challenging as they are prone to severe complications such as hemodynamic disturbances, infections, thromboses, and impaired growth, and most will develop end-stage kidney disease (ESKD) within a few years. Since the seventies, an "aggressive" approach, including daily albumin infusions, early nephrectomies, dialysis, and transplantation, has dramatically improved survival and morbidity. More recent case-note reviews have reported successful conservative treatment (using optimized nutrition, complication prophylaxis, and delayed renal replacement therapy), which led to similarly good outcomes and low complication rates. This questions the indications for early preemptive bilateral nephrectomy and dialysis given the mortality and morbidity rates in dialysis in infants and their life-long management with possible repeated transplantations. Two large series provide the most recent evidences supporting the conservative management: firstly, at least 55% children with CNS are not spontaneously in ESKD at the age of 2 years; secondly, albumin tapering/discontinuation and hospital discharge are possible before nephrectomy; and lastly, CNS complication rates are similar in case of preemptive nephrectomies or conservative care. Until now, no clear genotype-phenotype correlation has been identified to guide clinical management. Taken together, these data support the safety of conservative care until ESKD in a subset of patients with CNS.

Congenital Nephrotic Syndrome With a Novel Presentation in Saudi Arabia

Congenital nephrotic syndrome (CNS) is a rare and serious entity of renal diseases diagnosed in infants younger than three months. The triad of this syndrome is proteinuria, hypoalbuminemia, and edema. Without renal transplantation, these patients rarely live beyond the age of three years. Infections and sepsis are the most common causes of this condition among children. The majority of patients progress to end-stage renal disease early in life, even with aggressive supportive therapy. In this study, we present a case of a 10-year-old Saudi boy who had been diagnosed with CNS since he was two months old and has improved without renal transplantation.

Home Albumin Infusion Therapy, Another Alternative Treatment in Patients With Congenital Nephrotic Syndrome of the Finnish Type

Background: Congenital nephrotic syndrome of the Finnish type (CNF) is a rare, severe glomerular disease caused by mutations in the NPHS1 gene, which codes for nephrin. It is characterised by massive proteinuria and severe edoema. Progression to end-stage kidney failure occurs during early childhood and the only curative treatment is kidney transplantation. Nowadays, patients need aggressive medical treatment, which includes daily albumin infusions (for months) until they get clinical stability to receive transplant. Objective: In our paediatric hospital, we implemented a multidisciplinary program for the home infusion of albumin with outpatient follow-up. The aim of the study was to assess the safety and efficacy of this program for the first four years of its implementation. Material and Methods: Retrospective observational study of CNF paediatric patients treated with home albumin infusion therapy from March 2014 to July 2018 at a tertiary care paediatric hospital. Information on albumin administration was obtained from the electronic prescription assistance program and details on clinical and care-related variables from the hospital's electronic information systems. Results: Four patients with CNF received albumin infusions for 18, 21, 22 months, and 3 years. The treatment was safe, and the complication rates were to be expected considering the severity of disease. Patients required a median of two hospital admissions a year (19 in total); 47% due to catheter-related complications, but there were just three catheter infections. Conclusions: In our experience, home albumin infusion therapy is safe and effective and helps to improve children health and quality of life.

Diagnostic and Management Challenges in Congenital Nephrotic Syndrome

Congenital Nephrotic Syndrome (CNS) is defined as nephrotic range proteinuria, hypoalbuminaemia and edema in the first three months of life. CNS is most commonly genetic in cause, with international variance in the incidence of causative mutations. Initially defined by the histopathological appearance, increasingly sophisticated and accessible genetic analyses now provide a body of evidence to suggest that there is a disparity between the histological appearance, the genotype of individuals and the severity of the clinical disease. Through the evolution of management approaches CNS has changed from being an invariably fatal condition to one with appreciable ongoing morbidity and mortality but comparably good outcomes to other causes of paediatric end-stage renal disease, especially following transplantation. This review briefly summarises the more commonly recognised genetic mutations leading to CNS, addresses common management decisions, and concludes with potential therapies for the future.