Corticosteroid therapy for nephrotic syndrome in children

Efficacy and Safety of Mizoribine in comparison with Cyclophosphamide for Treatment of Refractory Nephrotic Syndrome: Protocol for a Multi-center, Controlled, Open-label, Randomized Controlled Trial (Preprint)

BACKGROUND

Nephrotic syndrome that is resistant to steroidal therapy is termed refractory nephrotic syndrome (RNS), a condition that is associated with an increased risk of end-stage renal disease (ESRD). Immunosuppressants are utilized to treat RNS, however prolonged may lead to significant adverse effects. Mizoribine (MZR) is a novel agent used in long-term immunosuppressive therapy that has few adverse effects, but data on its long-term use in patients with RNS are unavailable.

OBJECTIVE

We propose a trial to examine the efficacy and safety of MZR compared to cyclophosphamide (CYC) in Chinese adult patients with RNS.

METHODS

This is a multi-center, randomized, controlled interventional study with a screening phase (1 week) and a treatment phase (52 weeks). This study was reviewed and approved by the Medical Ethics Committees of all 34 medical centers. Patients with RNS consented to participation, and were enrolled and randomized into an MZR group or a CYC group (1:1 ratio), with each group receiving tapering doses of oral corticosteroids. Participants were assessed for adverse effects and collection of laboratory results at 8 visits during the treatment phase on week-4, week-8, week-12, week-16, week-20, week-32, week-44, and week-52 (exit visit). Participants were able to withdraw voluntarily and investigators were required to remove patients when there were safety concerns or deviations from protocol.

RESULTS

The study started in November 2014, and was completed in March 2019. A total of 239 participants from 34 hospitals in China were enrolled. Data analysis is completed. The results are waiting to be finalized by Center for Drug Evaluation.

CONCLUSIONS

The purpose of the current study is to evaluate the efficacy and safety of MZR in comparison with CYC for treatment of RNS in Chinese adult patients with glomerular diseases. It is the longest lasting and largest randomized controlled trial to examine MZR in Chinese patients. The results can help determine whether RNS should be considered as an additional indication for MZR treatment in China.

CLINICALTRIAL

ClinicalTrials.gov Register, NCT02257697. Registered 2014-10-01, https://clinicaltrials.gov/ct2/show/NCT02257697?term=MZR&rank=2.

Therapeutic trials in difficult to treat steroid sensitive nephrotic syndrome: challenges and future directions

Steroid sensitive nephrotic syndrome is a common condition in pediatric nephrology, and most children have excellent outcomes. Yet, 50% of children will require steroid-sparing agents due to frequently relapsing disease and may suffer consequences from steroid dependence or use of steroid-sparing agents. Several steroid-sparing therapeutic agents are available with few high quality randomized controlled trials to compare efficacy leading to reliance on observational data for clinical guidance. Reported trials focus on short-term outcomes such as time to first relapse, relapse rates up to 1-2 years of follow-up, and few have studied long-term remission. Trial designs often do not consider inter-individual variability, and differing response to treatments may occur due to heterogeneity in pathogenic mechanisms, and genetic and environmental influences. Strategies are proposed to improve the quantity and quality of trials in steroid sensitive nephrotic syndrome with integration of biomarkers, novel trial designs, and standardized outcomes, especially for long-term remission. Collaborative efforts among international trial networks will help move us toward a shared goal of finding a cure for children with nephrotic syndrome.

Fansidar drug induces cytotoxicity in some vital tissues in a rat model: combination defensive effect of selenium and zinc capsules

AIM

Fansidar (FAN) is widely used as an antimalarial drug, but it may cause hepatoxicity, nephrotoxicity, and neurotoxicity. Hence, the study examines the cytoprotection of selenium (Se) and zinc (Zn) tablets against FAN induced toxicity.

METHOD

Group I was given distilled water. Groups II, III, IV, and V received 50 mg/kg FAN by gavage. Group III was co-treated with a 50 mg/kg Se tablet. Group IV was co-treated with a 50 mg/kg Zn tablet. Group V was co-treated with a 50 mg/kg Se tablet + 50 mg/kg Zn tablet. The exposure lasted for 7 days (sub-acute exposure).

RESULT

FAN causes cytotoxicity through significant (p < 0.05) alteration of antioxidant molecules and hepatic enzymes. It also significantly (p < 0.05) induces renal, hepatocyte, and purkinje cell damage, but no visible lesion on testicular cells. The FAN induced cytotoxicity was significantly (p < 0.05) reversed on treatment with both single and combined antioxidant tablets.

CONCLUSION

Our study supports the view that antioxidant micronutrient (Se and Zn) tablets may be a useful modulator in alleviating FAN induced oxidative stress and cytotoxicity in male rats.

PLAIN LANGUAGE SUMMARY

Combined selenium and zinc capsules: better therapy against cytotoxicity Fansidar was approved by United States' Food and Drug Administration as an anti-malarial drug to treat acute and complicated malaria fever among patients in West Africa; however, its usage elicits toxicity to several organs of the body. It was elucidated that the combination of selenium and zinc capsules promotes organ wellness on co-treatment with Fansidar.

Childhood Idiopathic Nephrotic Syndrome: Does the Initial Steroid Treatment Modify the Outcome? A Multicentre, Prospective Cohort Study

Background: A great majority of children with idiopathic nephrotic syndrome will relapse after successful treatment of the initial episode. The possibility that different steroid dosing regimens at onset, adjusted for risk factors, can reduce the rate of relapse represents an interesting option to investigate. Objectives: To evaluate the effect of the initial steroid regimen, adjusted for time to remission (TTR), on the frequency of relapses and steroid dependence, and to verify the influence of prognostic factors on disease course. Methods: A multicentre, prospective, cohort study. Children with nephrotic syndrome, with TTR ≤ 10 days (Group A), were given a 20-week prednisone regimen (2,828 mg/m2) and those with a TTR >10 days, a 22-week regimen (3,668 mg/m2) (Group B). Previously published retrospective data from the same centers were also evaluated. Main outcomes were: relapse rate, number of frequent relapsers + steroid dependent children and total prednisone dose after induction. Results: 143 children were enrolled. Rate of relapsed subjects (77 vs. 79%) and frequent relapsers + steroid dependent subjects (40 vs. 53%) did not differ between Groups A and B, or between the retrospective and prospective cohorts. The cumulative prednisone dose taken after the induction treatment was similar in both groups and in the retrospective and prospective cohorts. TTR was not associated with relapse risk. Age at onset and total serum protein were significantly lower in relapsing patients. At ROC analysis, the best cut-off was 5.3 years for age at onset and 4.2 g/dL for total serum protein. According to these cut-offs, older children with higher total serum protein had a higher relapse free survival rate (58%) than younger children with lower total serum protein (17%). Conclusions: TTR was not found to be a prognostic factor of relapse; because of this, different steroid regimens, adjusted for TTR, did not modify the relapse rate in any relevant measure. Conversely, younger age and low total serum protein were independent predictors of relapse risk, however this outcome was not modified by higher prednisone regimens. Clinical Trial Registration:https://www.ClinicalTrials.gov/, identifier: NCT01386957 (www.nefrokid.it).

Pediatric idiopathic steroid-sensitive nephrotic syndrome: diagnosis and therapy -short version of the updated German best practice guideline (S2e) - AWMF register no. 166-001, 6/2020

Idiopathic nephrotic syndrome is the most frequent glomerular disease in children in most parts of the world. Children with steroid-sensitive nephrotic syndrome (SSNS) generally have a good prognosis regarding the maintenance of normal kidney function even in the case of frequent relapses. The course of SSNS is often complicated by a high rate of relapses and the associated side effects of repeated glucocorticoid (steroid) therapy. The following recommendations for the treatment of SSNS are based on the comprehensive consideration of published evidence by a working group of the German Society for Pediatric Nephrology (GPN) based on the systematic Cochrane reviews on SSNS and the guidelines of the KDIGO working group (Kidney Disease - Improving Global Outcomes).

Corticosteroid therapy for nephrotic syndrome in children

BACKGROUND

In nephrotic syndrome protein leaks from blood into the urine through the glomeruli resulting in hypoproteinaemia and generalised oedema. While most children with nephrotic syndrome respond to corticosteroids, 80% experience a relapsing course. Corticosteroids have reduced the death rate to around 3%. However, corticosteroids have well recognised potentially serious adverse effects such as obesity, poor growth, hypertension, diabetes mellitus, osteoporosis, and behavioural disturbances. This is an update of a review first published in 2000 and updated in 2002, 2005, 2007, and 2015.

OBJECTIVES

The aim of this review was to assess the benefits and harms of different corticosteroid regimens in children with steroid-sensitive nephrotic syndrome (SSNS). The benefits and harms of therapy were studied in two groups of children 1) children in their initial episode of SSNS, and 2) children who experience a relapsing course of SSNS.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 30 May 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) performed in children (one to 18 years) in their initial or subsequent episode of SSNS, comparing different durations, total doses or other dose strategies using any corticosteroid agent.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed risk of bias and extracted data. Results were expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

In this 2020 review update 16 new included studies were identified providing a total of 48 included studies with 3941 randomised participants. Risk of bias methodology was often poorly performed with only 25 studies and 22 studies respectively assessed to be at low risk for random sequence generation and allocation concealment. Only nine studies (19%) were at low risk of bias for performance (blinding of participants and personnel) and 11 studies were at low risk of detection bias (blinding of outcome assessment); nine of these studies were placebo-controlled RCTs. Twenty-two studies (fewer than 50%) were at low risk for attrition bias and 23 studies were at low risk for reporting bias (selective outcome reporting). In seven studies, which evaluated children in their initial episode of SSNS and were at low risk of bias for selection bias, there is little or no difference in the number of children with frequent relapses when comparing two months of prednisone with three months or more (RR 0.99, 95% CI 0.82 to 1.19; 585 participants, 4 studies; I2 = 0%) or when comparing three months with five to seven months of therapy (RR 0.99, 95% CI 0.74 to 1.33; 376 participants, 3 studies; I2 = 35%; high certainty evidence). In analyses of eight studies at low risk of selection bias, there is little or no difference in the number of children with any relapse by 12 to 24 months when comparing two months of prednisone with three months or more (RR 0.91, 95% CI 0.78 to 1.06; 637 participants; 5 studies; I2 = 47%) or when comparing three months with five to seven months of therapy (RR 0.88, 95% CI 0.70 to 1.11; 377 participants, 3 studies; I2 = 53%). Little or no difference was noted in adverse effects between the different treatment durations. Among children with relapsing SSNS, two small studies showed that time to remission did not differ between prednisone doses of 1 mg/kg compared with the conventional dose of 2 mg/kg (MD 0.71 days, 95% CI -0.43 to 1.86; 79 participants) and that the total prednisone dose administered was lower (MD -20.60 mg/kg, 95% CI -25.65 to -15.55; 20 participants). Two studies found little or no difference in the number with relapse at six months when comparing dosing by weight with dosing by surface area (RR 1.03, 95% CI 0.71 to 1.49; 146 participants). One study found a reduced risk of relapse with low daily dosing compared with alternate daily dosing (MD -0.90 number of relapses/year, 95% CI -1.33 to -0.47). Four studies found that in children with frequently relapsing disease, daily prednisone during viral infections compared with alternate-day prednisone or no treatment reduced the risk of relapse.

AUTHORS' CONCLUSIONS

There are now four well designed studies randomising 823 children which have clearly demonstrated that there is no benefit of prolonging prednisone therapy beyond two to three months in the first episode of SSNS. Small studies in children with relapsing disease have identified no differences in the times to remission using half the conventional induction dose of 2 mg/kg or 60 mg/m2. It is imperative that a much larger study be carried out to confirm these findings. Lower dose prednisone therapy administered daily during an upper respiratory infection or other infection reduces the risk of relapse compared with continuing alternate-day prednisone or no prednisone based on four small studies. The results of a much larger RCT enrolling more than 300 children are awaited to determine the relative efficacies and adverse effects of using alternate-day compared with daily prednisone to prevent relapse in children with intercurrent infections.

Population pharmacokinetics of tacrolimus in pediatric refractory nephrotic syndrome and a summary of other pediatric disease models

Different tacrolimus (TAC) population pharmacokinetic (PPK) models have been established in various pediatric disease populations. However, a TAC PPK model for pediatric refractory nephrotic syndrome (PRNS) has not been well characterized. The current study aimed to establish a TAC PPK model in Chinese PRNS and provide a summary of previous literature concerning TAC PPK models in different pediatric diseases. A total of 147 TAC conventional therapeutic drug monitoring (TDM) data from multiple blood samples obtained from 65 Chinese patients with PRNS were characterized using nonlinear mixed-effects modeling. The impacts of demographic features, biological characteristics and drug combination were evaluated. Model validation was assessed using the bootstrap method. A one-compartment model with first-order absorption and elimination was determined to be the most suitable model for TDM data in PRNS. The absorption rate constant (Ka) was set at 4.48 h⁻¹. The typical values of apparent oral clearance (CL/F) and apparent volume of distribution (V/F) in the final model were 5.46 l/h and 57.1 l, respectively. The inter-individual variability of CL/F and V/F were 22.2 and 0.2%, respectively. The PPK equation for TAC was: CL/F = 5.46 × exponential function (EXP)(0.0323 × age) × EXP(−0.359 × cystatin-C) × EXP(0.148 × daily dose of TAC). No significant effects of covariates on V/F were observed. In conclusion, the current study developed and validated the first TAC PPK model for patients with PRNS. The study also provided a summary of previous literature concerning other TAC PPK models in different pediatric diseases.

Clinical Use and Molecular Action of Corticosteroids in the Pediatric Age

Corticosteroids are the mainstay of therapy for many pediatric disorders and sometimes are life-saving. Both endogenous and synthetic derivatives diffuse across the cell membrane and, by binding to their cognate glucocorticoid receptor, modulate a variety of physiological functions, such as glucose metabolism, immune homeostasis, organ development, and the endocrine system. However, despite their proved and known efficacy, corticosteroids show a lot of side effects, among which growth retardation is of particular concern and specific for pediatric age. The aim of this review is to discuss the mechanism of action of corticosteroids, and how their genomic effects have both beneficial and adverse consequences. We will focus on the use of corticosteroids in different pediatric subspecialties and most common diseases, analyzing the most recent evidence.

Quality Improvement Initiative to Reduce Admissions for Nephrotic Syndrome Relapse in Pediatric Patients

Introduction: Childhood nephrotic syndrome is frequently seen in pediatric nephrology practice and often requires patient hospitalization for management. Numerous complications of this disease can be managed in an outpatient setting if brought to the attention of the medical team in a timely manner. Outpatient management will reduce healthcare cost and improve patient safety. The goal of this quality improvement initiative was to reduce admissions for nephrotic syndrome relapse from 8 to <5 admissions at a single center in a 3-month period. Methods: Fish-bone analysis was used to determine barriers to early recognition of relapse and successful outpatient care. Patient education about the disease process was identified as the primary barrier. A standardized approach to patient education as well as educational materials were developed. Champions were identified within each stakeholder group to train and disseminate the new process. Admission counts were compared from 3 years prior to implementation to 2 years post-implementation. Clinic visits for nephrotic syndrome were tallied as a balancing measure. Patients were surveyed in the outpatient clinics about whether they had ever received the education as a process measure. Results: Admission counts were reduced and met goal for the first 3 quarters that were examined; however, the number of admissions went above target in the last quarter. Clinic visit numbers did not change over the study period. Process measure showed that 75-80% of families were provided with nephrotic syndrome education. Conclusion: A standardized approach to patient and family education about idiopathic nephrotic syndrome can reduce admissions for management of relapse. This will reduce healthcare expenditure as well as improve patient safety.

Childhood nephrotic syndrome at the University of Abuja Teaching Hospital, Abuja, Nigeria: a preliminary report supports high steroid responsiveness

The response to steroid in childhood nephrotic syndrome (CNS) varies across geographical regions, depending on aetiology, genetics, and the underlying pathology. Recently, there is an increasing steroid responsiveness among Nigerian children with nephrotic syndrome (NS). This is the first report of CNS at the University of Abuja Teaching Hospital, Gwagwalada, Abuja, Nigeria, between 15th January 2016 and 30th June 2018. Prednisolone was administered to all the children with NS according to the regimen of the International Study of Kidney Disease in Children. There were 46 children aged 17 months to 18 years, including 37 males and 9 females. The peak age was 6-10 years with a mean age of 8.2 ± 4.4 years. Forty-one (89.1%) had idiopathic NS (INS). Secondary NS occurred in five (10.9%) children with hepatitis B infection, sickle cell anaemia, haemolytic-uraemic syndrome, and post-infectious glomerulonephritis (two cases). Plasmodium malariae was not seen. Overall, steroid-sensitive NS (SSNS) was seen in 34 (73.9%) and in 32 (78%) with INS. Five (16.7%) of the 30 with SSNS relapsed on follow-up. Twelve (26.1%) were resistant to steroid (steroid-resistant NS, SRNS). Renal biopsies in five SRNS revealed focal segmental glomerulosclerosis in three, minimal change lesion in one, and severe interstitial fibrosis/glomerulosclerosis in another one. Four (8.7%) children who had SRNS died. A child with SRNS is surviving on renal transplant from a living-unrelated donor. The study supports the notion that steroid responsiveness is increasing among ethnic black Nigerian children. Pre-treatment renal biopsy may be unwarranted.

Difficult-to-treat idiopathic nephrotic syndrome: established drugs, open questions and future options

The idiopathic nephrotic syndrome in childhood can be classified according to the International Study of Kidney Disease in Children (ISKDC) based on the response to steroids. Typically, steroid-sensitive nephrotic syndrome (SSNS) is characterised by minimal changes in disease (MCD) histology, whereas in steroid-resistant nephrotic syndrome (SRNS) focal segmental glomerulosclerosis (FSGS) is the most prevalent lesion. Patients with SSNS may develop frequent relapses and/or steroid dependency, which can be difficult to treat. New studies confirm the value of calcineurin inhibitors (CNIs) and mycophenolic acid in preventing relapses of SSNS. Rituximab also plays an important role, but many questions regarding initial dosing, repetitions of courses, and long-term side effects remain unclear. SRNS, especially when unresponsive to treatment, can lead to chronic kidney disease. In particular, treatment with CNIs has improved the prognosis and recent data indicate that treatment can even be discontinued in many patients with full remission. In CNI-unresponsive SRNS, rituximab is less effective than in SSNS and the role of other biologicals (such as ofatumumab, abatacept, and others) remains unclear. A significant proportion of children with FSGS have genetic causes and most patients do not respond to immunosuppression, although individual patients with partial and even complete response have been documented. Future studies should evaluate treatments leading to long-term remission without maintenance immunosuppression in SSNS; in both genetic and immune-mediated SRNS, novel options to decrease the number of treatment-unresponsive patients seem mandatory, as they are at a high risk of developing end-stage renal disease.

Induction prednisone dosing for childhood nephrotic syndrome: how low should we go?

BACKGROUND

Historically, children with nephrotic syndrome (NS) across British Columbia (BC), Canada have been cared for without formal standardization of induction prednisone dosing. We hypothesized that local historical practice variation in induction dosing was wide and that children treated with lower doses had worse relapsing outcomes.

METHODS

This retrospective cohort study included 92 NS patients from BC Children's Hospital (1990-2010). We excluded secondary causes of NS, age < 1 year at diagnosis, steroid resistance, and incomplete induction due to early relapse. We explored cumulative induction dose and defined dosing quartiles. Relapsing outcomes above and below each quartile threshold were compared including total relapses in 2 years, time to first relapse, and proportions developing frequently relapsing NS (FRNS) or starting a steroid-sparing agent (SSA).

RESULTS

Cumulative prednisone was widely distributed with approximated median, 1st, and 3rd quartile doses of 2500, 2000, and 3000 mg/m² respectively. Doses ≤ 2000 mg/m² showed significantly higher relapses (4.2 vs 2.7), shorter time to first relapse (61 vs 175 days), and higher SSA use (36 vs 14%) compared to higher doses. Doses ≤ 2500 mg/m² also showed significantly more relapses (3.9 vs 2.2), quicker first relapse (79 vs 208 days), and higher FRNS (37 vs 17%) and SSA use (28 vs 11%). Relapsing outcomes lacked statistical difference in ≤ 3000 vs > 3000 mg/m² doses.

CONCLUSIONS

Results strongly justify our development of a standardized, province-wide NS clinical pathway to reduce practice variation and minimize under-treatment. The lowest induction prednisone dosing threshold to minimize future relapsing risks is likely between 2000 and 2500 mg/m². Further prospective studies are warranted.

A randomized study on a 3-month versus a 7-month prednisolone regimen for the initial episode of childhood idiopathic nephrotic syndrome at a large Saudi center

BACKGROUND AND OBJECTIVES

The standard International Study of Kidney Disease in Children (ISKDC) regimen of prednisolone of 2 months duration for the treatment of the initial episode of Idiopathic Nephrotic Syndrome (INS) was associated with a high relapse rate. The long prednisolone protocols were introduced in order to reduce the relapse rate and steroid toxicities. The main objective of this study was to assess the efficacy and safety of a 3 months protocol of prednisolone versus a 7 months protocol for the first episode of idiopathic nephrotic syndrome.

DESIGN AND SETTING

The study took place in the Pediatric Nephrology Department of King Saud Medical City, Riyadh which is a large referral center all over Saudi Arabia. The study was a randomized control trial using 2 groups. Group A received the 3 months protocol and Group B received the 7 months protocol.

PATIENTS AND METHODS

All children with a confirmed diagnosis of Idiopathic Nephrotic Syndrome were included. The patients were randomized by simple randomization using sealed envelopes into two groups; group A comprised of 60 children using the daily regimen prednisolone 60 mg/m2 OD X 1 ½ months then 40mg/m2 on alternate day for 1 ½ months (total = 3 months) and group B also comprised of 60 children using the 7 months protocol, Prednisolone 60mg/m2 OD x 1 month then 40mg/m2 EOD x 2 months then 30mg/m2 EOD for 2 months then 20mg/m2 EOD for 2 months. The efficacy and safety of these two prednisolone regimens were recorded. The follow-up period was two years. Statistical analysis was done using the SPSS progress version 16 (Chicago, USA) P < .05 was taken as a significant result. Consort guidelines for randomized controlled trials (RCTs) were followed. The hospital ethical committee approved the study. The parents gave an informed consent.

RESULTS

Group B protocol was found to be significantly better than the group A protocol in both years of follow-up. The mean time of first relapse was significantly better in group B than in group A (P < .0001). The relapse rate reduced significantly in group B vs group A in both the first year (P = .0031) as well as in the second year (P = .00002). The cumulative dose of steroids was significantly less in group B vs group A both in the first year of follow-up (P = .0039) as well as in the second year (P = .0026). The incidence of frequently relapsers was significantly less (P = .049) in group B as compared to group A. The risk of relapse was better in group B as compared to group A (RR 0.8039; 95% CI 0.6566 to 0.9843 significance (P = .0346). The side effects of corticosteroids were significantly less in group B protocol as compared to group A.

CONCLUSION

We concluded that the long 7 months protocol was significantly better than the 3 months prednisolone regimen in both efficacy and safety for the initial episode of childhood INS.

Children with Steroid-Resistant Nephrotic Syndrome: A Single -Center Experience

Background

Nephrotic syndrome (NS) is one of the most frequent glomerular diseases among children. While most of the children with primary NS respond to steroid treatment, 10 to 20% of the patients are steroid-resistant, and the best therapy for such cases has never been defined.

Objective

The present study aimed to evaluate steroid-resistant nephrotic syndrome (SRNS) patients.

Materials and methods

Our research included 50 children (56% female and 44% male) with NS. NS was defined as the presence of edema, massive proteinuria, hypoalbuminemia and hyperlipidemia. Patients with NS were treated according to international protocol. SRNS was diagnosed in patients with idiopathic NS based on lack of complete remission despite treatment with steroids. Renal biopsy was performed in 22 patients with SRNS at the Pediatric Clinic II of the University Clinical Center in Sarajevo (UCCS). Histopathologic analyzes of renal biopsy were performed at the Department of Pathology, University Clinical Center in Tuzla (UCCT). Patients with SRNS, after kidney biopsy were treated with nonsteroidal immunosuppressant's.

Results

Eight (36.4%) of the 22 patients who had undergone renal biopsies had minimal change disease (MCNS) and seven (31.8%) had focal segmental glomerulosclerosis (FSGS). The immunosuppressive drugs used in SRNS were Cyclosporine (CsA), Cyclophosphamide (CYC), Mycophenolat mofetil (MMF) and Rituximab (RTX). Three patients (13.6%) did not respond to any treatment and had developed end - stage renal disease (ESRD).

Conclusion

With current treatments, some children will ultimately achieve a sustained remission with one of the second line or third line of the proposed drugs. Patients with refractory NS will go to progression towards ESRD. The rapid development of molecular genetics will give a new contribution to the pathogenesis and treatment of this disease.

B cell-derived IL-4 acts on podocytes to induce proteinuria and foot process effacement

The efficacy of B cell depletion therapies in diseases such as nephrotic syndrome and rheumatoid arthritis suggests a broader role in B cells in human disease than previously recognized. In some of these diseases, such as the minimal change disease subtype of nephrotic syndrome, pathogenic antibodies and immune complexes are not involved. We hypothesized that B cells, activated in the kidney, might produce cytokines capable of directly inducing cell injury and proteinuria. To directly test our hypothesis, we targeted a model antigen to the kidney glomerulus and showed that transfer of antigen-specific B cells could induce glomerular injury and proteinuria. This effect was mediated by IL-4, as transfer of IL-4-deficient B cells did not induce proteinuria. Overexpression of IL-4 in mice was sufficient to induce kidney injury and proteinuria and could be attenuated by JAK kinase inhibitors. Since IL-4 is a specific activator of STAT6, we analyzed kidney biopsies and demonstrated STAT6 activation in up to 1 of 3 of minimal change disease patients, suggesting IL-4 or IL-13 exposure in these patients. These data suggest that the role of B cells in nephrotic syndrome could be mediated by cytokines.

Factors influencing practice variation in the management of nephrotic syndrome: a qualitative study of pediatric nephrology care providers

BACKGROUND

Treatment protocols for childhood nephrotic syndrome are highly variable between providers and care centres. We conducted a qualitative study to understand the complex multilevel processes that lead to practice variation and influence provider management of nephrotic syndrome.

METHODS

Focus groups with multidisciplinary pediatric nephrology care providers (n = 67) from 10 Canadian pediatric nephrology centres that had more than 1 pediatric nephrologist were conducted between September 2013 and April 2015. Focus group discussions were guided by the Ottawa Model for Research Use. We used a semistructured interview guide to elicit participants' perspectives regarding 1) the work setting and context of the clinical environment, 2) reasons for variation at the provider level and 3) clinical practice guidelines for nephrotic syndrome. Focus group discussions were transcribed and analyzed concurrently with the use of qualitative content analysis.

RESULTS

Emerging themes were grouped into 2 categories: centre-level factors and provider-level factors. At the centre level, the type of care model used, clinic structures and resources, and lack of communication and collaboration within and between Canadian centres influenced care variation. At the provider level, use of experiential knowledge versus empirical knowledge and interpretation of patient characteristics influenced provider management of nephrotic syndrome.

INTERPRETATION

Centre- and provider-level factors play an important role in shaping practice differences in the management of childhood nephrotic syndrome. Further research is needed to determine whether variation in care is associated with disparities in outcomes.

Recent Treatment Advances and New Trials in Adult Nephrotic Syndrome

The etiology of nephrotic syndrome is complex and ranges from primary glomerulonephritis to secondary forms. Patients with nephrotic syndrome often need immunosuppressive treatment with its side effects and may progress to end stage renal disease. This review focuses on recent advances in the treatment of primary causes of nephrotic syndrome (idiopathic membranous nephropathy (iMN), minimal change disease (MCD), and focal segmental glomerulosclerosis (FSGS)) since the publication of the KDIGO guidelines in 2012. Current treatment recommendations are mostly based on randomized controlled trials (RCTs) in children, small RCTs, or case series in adults. Recently, only a few new RCTs have been published, such as the Gemritux trial evaluating rituximab treatment versus supportive antiproteinuric and antihypertensive therapy in iMN. Many RCTs are ongoing for iMN, MCD, and FSGS that will provide further information on the effectiveness of different treatment options for the causative disease. In addition to reviewing recent clinical studies, we provide insight into potential new targets for the treatment of nephrotic syndrome from recent basic science publications.

Variability of diagnostic criteria and treatment of idiopathic nephrotic syndrome across European countries

The aim of the surveys conducted by the Idiopathic Nephrotic Syndrome Working Group of the ESPN was to study the possible variability of treatment in Europe at different stages of the disease by means of questionnaires sent to members of the Working Group. Four surveys have been completed: treatment of the first flare, treatment of the first relapse and the issue of steroid dependency, use of rituximab, and the management of steroid-resistant patients. A uniform treatment of the first flare was applied in only three countries, and ten additional centers have adopted one of the three main protocols. Reported treatment of the first relapse was relatively uniform, whereas the use of additional immunosuppressants in steroid dependency was widely variable. Rituximab had already been used in hundreds of patients, although the formal evidence of efficiency in steroid dependency was relatively recent at the time of the survey. The definition of steroid resistance was variable in the European centers, but strikingly, the first-line treatment was uniform throughout the centers and included the combination of prednisone plus calcineurin antagonists.

CONCLUSION

The variability in the approach of idiopathic nephrotic syndrome is unexpectedly large and affects treatment of the first flare, strategies in the case of steroid dependency, as well as the definitions of steroid resistance. What is Known: • Steroids and immunosuppressants are the universal treatment of idiopathic nephrotic syndrome. What is New: • The variability of treatments and strategy of treatment in European centers of pediatric nephrology.

Cytoplasmic Localization of WT1 and Decrease of miRNA-16-1 in Nephrotic Syndrome

Nephrotic syndrome (NS) is a glomerular disease that is defined by the leakage of protein into the urine and is associated with hypoalbuminemia, hyperlipidemia, and edema. Steroid-resistant NS (SRNS) patients do not respond to treatment with corticosteroids and show decreased Wilms tumor 1 (WT1) expression in podocytes. Downregulation of WT1 has been shown to be affected by certain microRNAs (miRNAs). Twenty-one patients with idiopathic NS (68.75% were SSNS and 31.25% SRNS) and 10 healthy controls were enrolled in the study. Podocyte number and WT1 location were determined by immunofluorescence, and the serum levels of miR-15a, miR-16-1, and miR-193a were quantified by RT-qPCR. Low expression and delocalization of WT1 protein from the nucleus to the cytoplasm were found in kidney biopsies of patients with SRNS and both nuclear and cytoplasmic localization were found in steroid-sensitive NS (SSNS) patients. In sera from NS patients, low expression levels of miR-15a and miR-16-1 were found compared with healthy controls, but only the miR-16-1 expression levels showed statistically significant decrease (p = 0.019). The miR-193a expression levels only slightly increased in NS patients. We concluded that low expression and delocalization from the WT1 protein in NS patients contribute to loss of podocytes while modulation from WT1 protein is not associated with the miRNAs analyzed in sera from the patients.

Predictive risk factors of steroid dependent nephrotic syndrome in children

Background:

Development of steroid dependency is one of the difficult problems in the management of children with idiopathic nephrotic syndrome, leading to increased morbidity, complications and cost of treatment. Thus, predicting early in the disease course will be useful in counseling parents and may improve treatment strategy.

Objectives:

To determine the clinical characteristics that can predict the development of steroid dependency early in the initial episodes of steroid sensitive nephrotic syndrome (SSNS).

Patients and Methods:

The study included 52 children with SSNS. Their ages ranged from 3 to 16 years. Patients were divided into two groups. Group A consisted of 24 patients with steroid dependency or frequent relapses nephrotic syndrome and group B consisted of 28 patients with complete remission or recurrent nephrotic syndrome. Data obtained retrospectively from patients’ files.

Results:

Children who require a cumulative steroid dose equal or more than 140 mg/kg to maintain remission during the first 6 months of the disease are at high risk to require steroid sparing agents (SSA) for disease control, and who did not achieve remission by day 20 of the initial prednisone course became steroid dependent with 96% specificity but with low sensitivity (50%). All steroid dependent children in this study showed relapses associated significantly with upper respiratory tract infections.

Conclusions:

Cumulative steroid dose in the first 6 months of treatment and the need of more than 20 days to achieve initial remission can predict steroid dependency in children with nephrotic syndrome.

Body weight-based prednisolone versus body surface area-based prednisolone regimen for induction of remission in children with nephrotic syndrome: a randomized, open-label, equivalence clinical trial

BACKGROUND

Body surface area (BSA)-based prednisolone dosing for childhood nephrotic syndrome (NS) leads to higher cumulative prednisolone doses than body weight (BW)-based dosing. The clinical effects of this higher dosage have not been evaluated in prospective studies.

METHODS

This parallel-group open-label randomized clinical trial enrolled 100 children with idiopathic NS, to receive BW-based (n = 50) or BSA-based (n = 50) prednisolone dosing by block randomization in a 1:1 ratio. The time taken for remission, relapse rate per 6 months, and adverse effects of steroids were analyzed in both groups.

RESULTS

There was no significant difference in the time taken for remission in the BW group versus the BSA group (median (IQR) 7 (4.5-9) versus 5.5 (4-8) days; p = 0.082); similar results were observed on subgroup analysis in new-onset and infrequently-relapsing NS (IFRNS). The cumulative prednisolone dosage during the enrolment episode was higher in the BSA group. The incidence of hypertension was higher (p = 0.048) in the BSA group on per-protocol analysis. The relapse rates in the two groups per 6 months on follow-up were comparable.

CONCLUSIONS

Clinical outcomes with BW-based dosing are equivalent to BSA dosing-related outcomes, although cumulative prednisolone doses are lower in the former. The practice of BW-based calculations for prescribing prednisolone in NS is a reasonable approach.

Tacrolimus for children with refractory nephrotic syndrome: a one-year prospective, multicenter, and open-label study of Tacrobell®, a generic formula

BACKGROUND

Cyclosporine A and tacrolimus (TAC) are often used as a second-line treatment for children with refractory nephrotic syndrome (NS). This study was undertaken to investigate the efficacy and safety of Tacrobell®, a locally produced generic form of TAC.

METHODS

This study was a one-year prospective, open-label, single-arm, multicenter trial. Fourty-four children with steroid-dependent NS (SDNS) and 33 children with steroid-resistant NS (SRNS) were enrolled. The primary endpoints were defined as the remission rates, whereas the secondary endpoints were recognized as the duration of remission and adverse effects of TAC.

RESULTS

After one-year treatment, 34 (77.3%) of the 44 patients with SDNS were in complete remission, and 6 (13.6%) were in partial remission. Nineteen (43.2%) patients did not relapse during the study; for those who did relapse, the mean duration of remission was 4.6±2.9 months. The number of relapse episodes during the study period (0.90 per patient-year) was significantly lower than that in the preceding year (2.8 per patient-year). After treatment for 3 and 6 months, 12 (36.4%) of the 33 patients with SRNS were in remission, and after treatment for 12 months, the number of patients had increased to 13 (39.4%). The mean time to achieve remission was 4.0±3.2 months. After remission (duration, 3.7±2.7 months), 12 (54.5%) of 22 patients relapsed. The fasting blood glucose and blood pressure levels during the therapy were similar to those at the time of study entry.

CONCLUSIONS

Treatment with Tacrobell® was effective and safe for children with refractory NS. The efficacy of this generic form of TAC was better than that of the original TAC formula.

Pro: 'The usefulness of biomarkers in glomerular diseases'. The problem: moving from syndrome to mechanism--individual patient variability in disease presentation, course and response to therapy

The diagnosis and treatment decisions in glomerular disease are principally based on renal pathology and nonspecific clinical laboratory measurements such as serum creatinine and urine protein. Using these classification approaches, patients have marked variability in rate of progression and response to therapy, exposing a significant number of patients to toxicity without benefit. Additionally, clinical trials are at risk of not being able to detect an efficacious therapy in relevant subgroups as patients with shared clinical-pathologic diagnoses have heterogeneous underlying pathobiology. To change this treatment paradigm, biomarkers that reflect the molecular mechanisms underlying the clinical-pathologic diagnoses are needed. Recent progress to identify such biomarkers has been aided by advances in molecular profiling, large-scale data generation and multi-scalar data integration, including prospectively collected clinical data. This article reviews the evolving success stories in glomerular disease biomarkers across the genotype-phenotype continuum and highlights opportunities to transition to precision medicine in glomerular disease.

Childhood nephrotic syndrome in the 21st century: What's new?

Childhood nephrotic syndrome is a condition managed by general paediatricians and paediatric nephrologists. Whether treating a first presentation or a relapse, the clinician requires expertise in order to minimise the risk of serious complications and optimise long-term care. Indeed, many children suffer a difficult relapsing course in their disease, warranting consideration of second-line therapies. The last two decades have witnessed a growing knowledge of the condition and increased complexity of diagnostic and therapeutic options, which poses a challenge for the general paediatrician, given the condition's relative rarity in daily practice. This review aims to familiarise the reader with some of the most important recent developments and particularly to provide an insight into what management options are available and when it may be appropriate to seek advice from a nephrologist.

Corticosteroid therapy for nephrotic syndrome in children

BACKGROUND

In nephrotic syndrome protein leaks from the blood to the urine through the glomeruli resulting in hypoproteinaemia and generalised oedema. While most children with nephrotic syndrome respond to corticosteroids, 80% experience a relapsing course. Corticosteroids have reduced the mortality rate to around 3%. However corticosteroids have well recognised potentially serious adverse effects such as obesity, poor growth, hypertension, diabetes mellitus, osteoporosis and behavioural disturbances. This is an update of a review first published in 2000 and updated in 2003, 2005 and 2007.

OBJECTIVES

The aim of this review was to assess the benefits and harms of different corticosteroid regimens in children with steroid-sensitive nephrotic syndrome (SSNS). The benefits and harms of therapy were studied in two groups of children 1) children in their initial episode of SSNS, and 2) children who experience a relapsing course of SSNS.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 26 February 2015 through contact with the Trials Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

Randomised controlled trials (RCTs) performed in children (three months to 18 years) in their initial or subsequent episode of SSNS, comparing different durations, total doses or other dose strategies using any corticosteroid agent.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed risk of bias and extracted data. Results were expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

Ten new studies were identified so a total of 34 studies (3033 total participants) were included in the 2015 review update. The risk of bias attributes were frequently poorly performed. Low risk of bias was reported in 18 studies for sequence generation, 16 studies for allocation concealment, seven for performance and detection bias, 15 for incomplete reporting and 16 for selective reporting. Three months or more of prednisone significantly reduced the risk of frequently relapsing nephrotic syndrome (FRNS) (6 studies, 582 children: RR 0.68, 95% CI 0.47 to 1.00) and of relapse by 12 to 24 months (8 studies, 741 children: RR 0.80, 95% CI 0.64 to 1.00) compared with two months. Five or six months of prednisone significantly reduced the risk of relapse (7 studies, 763 children: RR 0.62, 95% CI 0.45 to 0.85) but not FRNS (5 studies, 591 children: RR 0.78, 95% CI 0.50 to 1.22) compared with three months. However there was significant heterogeneity in the analyses. Subgroup analysis stratified by risk of bias for allocation concealment showed that the risk for FRNS did not differ significantly between two or three months of prednisone and three to six months among studies at low risk of bias but was significantly reduced in extended duration studies compared with two or three months in studies at high risk or unclear risk of bias. There were no significant differences in the risk of adverse effects between extended duration and two or three months of prednisone. Four studies found that in children with FRNS, daily prednisone during viral infections compared with alternate-day prednisone or no treatment significantly reduced the rate of relapse.

AUTHORS' CONCLUSIONS

In this 2015 update the addition of three well-designed studies has changed the conclusion of this review. Studies of long versus shorter duration of corticosteroids have heterogeneous treatment effects, with the older high risk of bias studies tending to over-estimate the effect of longer course therapy, compared with more recently published low risk of bias studies. Among studies at low risk of bias, there was no significant difference in the risk for FRNS between prednisone given for two or three months and longer durations or total dose of therapy indicating that there is no benefit of increasing the duration of prednisone beyond two or three months in the initial episode of SSNS.The risk of relapse in children with FRNS is reduced by the administration of daily prednisone at onset of an upper respiratory tract or viral infection. Three additional studies have increased the evidence supporting this conclusion. This management strategy may be considered for children with FRNS. A paucity of data on prednisone use in relapsing nephrotic syndrome remains. In particular there are no data from RCTs evaluating the efficacy and safety of prolonged courses of low dose alternate-day prednisone although this management strategy is recommended in current guidelines.

Glomerular nestin expression: possible predictor of outcome of focal segmental glomerulosclerosis in children

BACKGROUND

A high prevalence of chronic kidney disease among children with focal segmental glomerulosclerosis (FSGS) leads to a permanent quest for good predictors of kidney dysfunction. Thus, we carried out a retrospective cohort study in order to examine known clinical and morphological predictors of adverse outcome, as well as to investigate glomerular nestin expression as a potential new early predictor of kidney dysfunction in children with FSGS. Relationships between nestin expression and clinical and morphological findings were also investigated.

METHODS

Among 649 renal biopsy samples, obtained from two children's hospitals, FSGS was diagnosed in 60 children. Thirty-eight patients, who met the criteria for this study, were followed up for 9.0 ± 5.2 years. Using Kaplan-Meier and Cox's regression analysis, potential clinical and morphological predictors were applied in two models of prediction: after disease onset and after the biopsy.

RESULTS

The present study revealed the following significant predictors of kidney dysfunction: patients' ages at disease onset, as well as age at biopsy, resistance to corticosteroid treatment, serum creatinine level, urine protein/creatinine ratio, vascular involvement, tubular atrophy, interstitial fibrosis, and decreased glomerular nestin expression.

CONCLUSIONS

The most important finding of our study is that nestin can be used as a potential new early morphological predictor of kidney dysfunction in childhood onset of FSGS, since nestin has been obviously decreased in both sclerotic and normal glomeruli seen by light microscopy.

A multicenter randomized trial indicates initial prednisolone treatment for childhood nephrotic syndrome for two months is not inferior to six-month treatment

In this multicenter, open-label, randomized controlled trial, we determined whether 2-month prednisolone therapy for steroid-sensitive nephrotic syndrome was inferior or not to 6-month therapy despite significantly less steroid exposure. The primary end point was time from start of initial treatment to start of frequently relapsing nephrotic syndrome. The pre-specified non-inferiority margin was a hazard ratio of 1.3 with one-sided significance of 5%. We randomly assigned 255 children with an initial episode of steroid-sensitive nephrotic syndrome to either 2 - or 6-month treatment of which 246 were eligible for final analysis. The total prednisolone exposure counted both initial and relapse prednisolone treatment administered over 24 months. Median follow-up in months was 36.7 in the 2-month and 38.2 in the 6-month treatment group. Time to frequent relaps was similar in both groups; however, the median was reached only in the 6-month group (799 days). The hazard ratio was 0.86 (90% confidence interval, 0.64–1.16) and met the non-inferior margin. Time to first relapse was also similar in both groups: median day 242 (2-month) and 243 (6-month). Frequency and severity of adverse events were similar in both groups. Most adverse events were transient and occurred during initial or relapse therapy. Thus, 2 months of initial prednisolone therapy for steroid-sensitive nephrotic syndrome, despite less prednisolone exposure, is not inferior to 6 months of initial therapy in terms of time to onset of frequently relapsing nephrotic syndrome.

The Canadian Childhood Nephrotic Syndrome (CHILDNEPH) Project: overview of design and methods

Background

Nephrotic syndrome is a commonly acquired kidney disease in children that causes significant morbidity due to recurrent episodes of heavy proteinuria. The management of childhood nephrotic syndrome is known to be highly variable among physicians and care centres.

Objectives

The primary objective of the study is to determine centre-, physician-, and patient-level characteristics associated with steroid exposure and length of steroid treatment. We will also determine the association of dose and duration of steroid treatment and time to first relapse as a secondary aim. An embedded qualitative study utilizing focus groups with health care providers will enrich the quantitative results by providing an understanding of the attitudes, beliefs and local contextual factors driving variation in care.

Design

Mixed-methods study; prospective observational cohort (quantitative component), with additional semi-structured focus groups of healthcare professionals (qualitative component).

Setting

National study, comprised of all 13 Canadian pediatric nephrology clinics.

Patients

400 patients under 18 years of age to be recruited over 2.5 years.

Measurements

Steroid doses for all episodes (first presentation, first and subsequent relapses) tracked over course of the study. Physician and centre-level characteristics catalogued, with reasons for treatment preferences documented during focus groups.

Methods

All patients tracked prospectively over the course of the study, with data comprising a prospective registry. One focus group at each site to enrich understanding of variation in care.

Limitations

Contamination of treatment protocols between physicians may occur as a result of concurrent focus groups.

Conclusions

Quantitative and qualitative results will be integrated at end of study and will collectively inform strategies for the development and implementation of standardized evidence-based protocols across centres.

Effects of dexamethasone on angiotensin II-induced changes of monolayer permeability and F-actin distribution in glomerular endothelial cells

The aim of this study was to investigate the changes in monolayer permeability and F-actin distribution caused by angiotensin II (Ang II)-induced injury in glomerular endothelial cells (GENCs) and the effects of dexamethasone on these changes. GENCs isolated and cultured from Wistar rats were used to examine the changes in monolayer permeability and F-actin distribution induced by Ang II. GENC permeability was evaluated by measuring the diffusion of biotin-conjugated bovine serum albumin (biotin-BSA) across a cell monolayer. The expression levels and distribution of F-actin were assessed by flow cytometry. The biotin-BSA concentrations were measured by capture enzyme-linked immunosorbent assay. Ang II at a concentration of 10 mg/l increased the permeability of the GENC monolayer at 6 h and 12 h (P<0.05 and P<0.01, respectively) and caused F-actin depolymerisation at 6 h and 12 h (P<0.01). The two effects attributed to Ang II were significantly inhibited by dexamethasone treatment (P<0.01). The increased permeability of the GENC monolayer induced by Ang II was significantly correlated with the depolymerisation of F-actin. Dexamethasone abrogated the Ang II-mediated damage to GENCs indicating that it may play an important role in protecting GENCs from injury.

Mycophenolate mofetil versus cyclosporin A in children with frequently relapsing nephrotic syndrome

The severe side effects of long-term corticosteroid or cyclosporin A (CsA) therapy complicate the treatment of children with frequently relapsing steroid-sensitive nephrotic syndrome (FR-SSNS). We conducted a randomized, multicenter, open-label, crossover study comparing the efficacy and safety of a 1-year treatment with mycophenolate mofetil (MMF; target plasma mycophenolic acid trough level of 1.5-2.5 µg/ml) or CsA (target trough level of 80-100 ng/ml) in 60 pediatric patients with FR-SSNS. We assessed the frequency of relapse as the primary endpoint and evaluated pharmacokinetic profiles (area under the curve [AUC]) after 3 and 6 months of treatment. More relapses per patient per year occurred with MMF than with CsA during the first year (P=0.03), but not during the second year (P=0.14). No relapses occurred in 85% of patients during CsA therapy and in 64% of patients during MMF therapy (P=0.06). However, the time without relapse was significantly longer with CsA than with MMF during the first year (P<0.05), but not during the second year (P=0.36). In post hoc analysis, patients with low mycophenolic acid exposure (AUC <50 µg⋅h/ml) experienced 1.4 relapses per year compared with 0.27 relapses per year in those with high exposure (AUC>50 µg⋅h/ml; P<0.05). There were no significant differences between groups with respect to BP, growth, lipid levels, or adverse events. However, cystatin clearance, estimated GFR, and hemoglobin levels increased significantly with MMF compared with CsA. These results indicate that MMF is inferior to CsA in preventing relapses in pediatric patients with FR-SSNS, but may be a less nephrotoxic treatment option.

Extending prednisolone treatment does not reduce relapses in childhood nephrotic syndrome

Prolonged prednisolone treatment for the initial episode of childhood nephrotic syndrome may reduce relapse rate, but whether this results from the increased duration of treatment or a higher cumulative dose remains unclear. We conducted a randomized, double-blind, placebo-controlled trial in 69 hospitals in The Netherlands. We randomly assigned 150 children (9 months to 17 years) presenting with nephrotic syndrome to either 3 months of prednisolone followed by 3 months of placebo (n=74) or 6 months of prednisolone (n=76), and median follow-up was 47 months. Both groups received equal cumulative doses of prednisolone (approximately 3360 mg/m(2)). Among the 126 children who started trial medication, relapses occurred in 48 (77%) of 62 patients who received 3 months of prednisolone and 51 (80%) of 64 patients who received 6 months of prednisolone. Frequent relapses, according to international criteria, occurred with similar frequency between groups as well (45% versus 50%). In addition, there were no statistically significant differences between groups with respect to the eventual initiation of prednisolone maintenance and/or other immunosuppressive therapy (50% versus 59%), steroid dependence, or adverse effects. In conclusion, in this trial, extending initial prednisolone treatment from 3 to 6 months without increasing cumulative dose did not benefit clinical outcome in children with nephrotic syndrome. Previous findings indicating that prolonged treatment regimens reduce relapses most likely resulted from increased cumulative dose rather than the treatment duration.

Treatment of steroid-sensitive nephrotic syndrome: new guidelines from KDIGO

The 2012 Kidney Disease: Improving Global Outcomes (KDIGO) clinical practice guideline on glomerulonephritis (GN) is intended to assist the practitioner caring for patients with GN. Two chapters of this guideline focus specifically on nephrotic syndrome in children. Guideline development followed a thorough evidence review, and management recommendations and suggestions were based on the best available evidence. Critical appraisal of the quality of evidence and strength of recommendations followed the Grades of Recommendation Assessment, Development and Evaluation (GRADE) approach. Chapters 3 and 4 of the guideline focus on the management of nephrotic syndrome in children aged 1-18 years. Guideline recommendations for children who have steroid-sensitive nephrotic syndrome (SNSS), defined by their response to corticosteroid therapy with complete remission, are addressed here. Recommendations for those with steroid-resistant nephrotic syndrome (SRNS) (i.e., do not achieve complete remission) are discussed in the companion article. Limitations of the evidence, including the paucity of large-scale randomized controlled trials, are discussed. This article provides a short description of the KDIGO process, the guideline recommendations for treatment of SSNS in children and a brief review of relevant treatment trials related to each recommendation.

Two-year outcome of the ISKDC regimen and frequent-relapsing risk in children with idiopathic nephrotic syndrome

BACKGROUND AND OBJECTIVES

Early identification of frequently relapsing children with idiopathic nephrotic syndrome is desirable.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The relapse status and clinical data of patients previously registered (January of 1993 to December of 2001) in a multicenter prospective study of the International Study of Kidney Disease in Children regimen were analyzed for risk of frequent relapsers over a 2-year follow-up period.

RESULTS

Of 166 children with nephrotic syndrome (113 boys and 53 girls; median age=5.1 years), 145 (87.3%, median age=5.5 years) children were steroid-sensitive, and 21 (12.7%, median age=2.9 years) children were steroid-resistant. Of 145 children with steroid-sensitive nephrotic syndrome, 32 (22.1%, median age=4.2 years) children experienced frequent relapses over 2 years. The time to initial response was significantly longer (10 versus 7 days, P<0.001, log-rank test) in the 32 frequent relapsers than in the 106 nonfrequent relapsers. The time from start of initial treatment to first relapse was significantly shorter (2.6 versus 6.1 months, P<0.001, log-rank test) in the 32 frequent relapsers than in the 57 infrequent relapsers. In a Cox regression model, the time to initial response ≥9 days and the duration from start of initial treatment to first relapse <6 months were significant predictors of frequent relapses (unadjusted and adjusted).

CONCLUSIONS

Initial remission time ≥9 days and first relapse within 6 months were associated with frequent relapses. These findings may also be useful also in selecting potential frequent relapsers for clinical trials.

Deflazacort in comparison to other steroids for nephrotic syndrome

Patients with nephrotic syndrome require steroids for long time and sometimes repeatedly resulting in various adverse effects. Deflazacort (DFZ) had been described as equally effective and with fewer side effects as compared with other steroids. This review evaluates the literature on efficacy and toxicity of DFZ as compared with other therapies for nephrotic syndrome. A systematic review of Pubmed database and Cochrane Central Register of Controlled Trials with last search date of 20(th) April 2011. Search terms included "nephrotic AND deflazacort" without any limitations. Randomized control trials comparing DFZ vs placebo or other therapies in subjects with nephrotic syndrome were included. Two authors extracted data independently. Three studies meet inclusion criteria and data were synthesized qualitatively. The limited evidence suggested that DFZ appeared to be equally effective in inducing remission or decreasing proteinuria in patients with nephrotic syndrome. It caused significantly less decrease in bone mineral content (BMC) in spine as compared with prednisolone. The results related to weight change, blood pressure change, Cushingoid symptoms, and urinary calcium excretion were inconsistent between included studies. By reviewing the available limited evidence, DFZ appears to be of similar efficacy for nephrotic patients, but there were inconsistent results regarding side effect profile of DFZ as compared with other steroids except for decrease in BMC where DFZ was better. There is need for larger randomized controlled trials to evaluate effectiveness and adverse effect profile of DFZ as compared with other steroids in nephrotic syndrome.

Nephrotic syndrome

The pathogenetic basis of idiopathic nephrotic syndrome, a common childhood glomerulopathy, is being explored. While initial evidence supported an imbalance of T helper responses, recent studies suggest alterations in both innate and adaptive immune responses, including evidence for impaired T regulatory function. The central role of the podocyte in causing proteinuria is confirmed by the observation of mutations in key podocyte proteins in steroid resistant nephrotic syndrome and experimental evidence of altered podocyte signaling and cytoskeletal organization. The outcome and management of idiopathic nephrotic syndrome in children is determined by the response to corticosteroids and the frequency of relapses. While patients with steroid sensitive nephrotic syndrome have a favorable long term outcome, almost half of them relapse frequently and are at risk of adverse effects of corticosteroids. Although various non-corticosteroid immunosuppressive agents are used to prolong disease remission, careful monitoring is required for the potential adverse effects. Calcineurin inhibitors have emerged as the choice of therapy in patients with steroid resistant nephrotic syndrome. However, the management of this form of the disease is particularly challenging because of the variable response to immunosuppression, therapy-related significant adverse effects and high rates of disease progression to end stage renal disease. Patients with both corticosteroid sensitive and resistant forms of the disease are at risk of complications of disease, and require close monitoring and repeated counseling.

Weight or body surface area dosing of steroids in nephrotic syndrome: is there an outcome difference?

Although prednisone is the treatment of choice for nephrotic syndrome (NS) in childhood, the dosing regimen varies between 60 mg/m(2)/day, as recommended in early studies, to the often prescribed 2 mg/kg/day dose, which is used in common practice. Mathematical models have demonstrated that weight-based dosing can be less than body surface area (BSA)-based dosing in smaller children. To test our hypothesis that weight-based dosing would result in altered treatment outcomes in children with NS, we analyzed a cohort of 56 children (mean age 5.4 ± 3.8 years) treated with a weight-based dosing regimen. Theoretical underdosing of corticosteroids was tested by calculating a relative underdosing percentage (RUP), which was defined as the dose difference between the theoretical BSA-based dose and the actual weight-based doses divided by the BSA-based dose × 100. We found that the mean "actual" prednisone dose in our patients was 43.6 ± 19.3 mg/day; in contrast, the mean theoretical BSA-based dose was calculated to be 48.8 ± 16.7 mg/day. Among the 56 patients, 43 (76.7%) were initial responders, of whom 58% followed a frequently relapsing (FR) course. RUP was significantly higher in FR (16.6 ± 7.9%) than in infrequent relapsers (8.7 ± 9.8%) (P = 0.03). RUP was not significantly different among initial responders and nonresponders. Based on these results, we conclude that prednisone underdosing, when dosing is prescribed according to weight, does not affect the initial response to treatment, but it does increase the likelihood of a FR course in responders.

Complications of nephrotic syndrome

Nephrotic syndrome (NS) is one of the most common glomerular diseases that affect children. Renal histology reveals the presence of minimal change nephrotic syndrome (MCNS) in more than 80% of these patients. Most patients with MCNS have favorable outcomes without complications. However, a few of these children have lesions of focal segmental glomerulosclerosis, suffer from severe and prolonged proteinuria, and are at high risk for complications. Complications of NS are divided into two categories: disease-associated and drug-related complications. Disease-associated complications include infections (e.g., peritonitis, sepsis, cellulitis, and chicken pox), thromboembolism (e.g., venous thromboembolism and pulmonary embolism), hypovolemic crisis (e.g., abdominal pain, tachycardia, and hypotension), cardiovascular problems (e.g., hyperlipidemia), acute renal failure, anemia, and others (e.g., hypothyroidism, hypocalcemia, bone disease, and intussusception). The main pathomechanism of disease-associated complications originates from the large loss of plasma proteins in the urine of nephrotic children. The majority of children with MCNS who respond to treatment with corticosteroids or cytotoxic agents have smaller and milder complications than those with steroid-resistant NS. Corticosteroids, alkylating agents, cyclosporin A, and mycophenolate mofetil have often been used to treat NS, and these drugs have treatment-related complications. Early detection and appropriate treatment of these complications will improve outcomes for patients with NS.

Nephrotic syndrome in children: from bench to treatment

Idiopathic nephrotic syndrome (INS) is the most frequent form of NS in children. INS is defined by the association of the clinical features of NS with renal biopsy findings of minimal changes, focal segmental glomerulosclerosis (FSGS), or mesangial proliferation (MP) on light microscopy and effacement of foot processes on electron microscopy. Actually the podocyte has become the favourite candidate for constituting the main part of the glomerular filtration barrier. Most cases are steroid sensitive (SSINS). Fifty percents of the latter recur frequently and necessitate a prevention of relapses by nonsteroid drugs. On the contrary to SSINS, steroid resistant nephrotic syndrome (SRINS) leads often to end-stage renal failure. Thirty to forty percents of the latter are associated with mutations of genes coding for podocyte proteins. The rest is due to one or several different circulating factors. New strategies are in development to antagonize the effect of the latter.

Clinical course and outcome of children with steroid-sensitive nephrotic syndrome

We conducted a retrospective study on children with primary nephrotic syndrome (NS) to evaluate the clinical course and outcome of children with steroid-sensitive NS (SSNS). The medical records of 226 children, median 3.46 years (min 1.00, max 15.08) who referred to our clinics with SSNS between January 1978 and September 2005 were reviewed and entered into the study. Minimum duration of follow-up was 5 years and maximum 20 years (median 7.25 years). Of 226 patients who were treated with corticosteroids, 38 (16.8%) had no relapse but the remaining 188 (83.2%) patients experienced several relapses of which 128 patients (56.6%) required additional immunosuppressive agents for the remission. Of these, 122 (95%) were treated with levamisole, 22 (17%) with cyclosporine, 36 (28%) with cyclophosphamide, and ten (7.8 %) treated with mycophenolate mofetil. Several patients had to switch from one medication to others due to lack of response. On the last follow-up visit, 64(28.3%) patients were still under treatment, some patients had taken all of the above-mentioned drugs but still had multiple recurrences. Only 103 (45.5%) patients were in remission off the drug more than 3 years. This study shows that nearly one-third of pediatric patients with SSNS experience frequent relapses despite the combination of multiple immunosuppressive medications, which may continue until adulthood.