Prediction of steroid-sparing agent use in childhood idiopathic nephrotic syndrome

Timing of relapse as a key indicator of steroid-sparing requirements in childhood idiopathic nephrotic syndrome

BACKGROUND

Managing children with frequent relapses or steroid-dependent nephrotic syndrome poses challenges due to recurrent relapses necessitating prolonged steroid exposure, thus increasing susceptibility to long-term complications. Identifying those at risk of poor response to steroid therapy may be helpful to guide timely intervention with steroid-sparing agents. This study aimed to identify factors associated with steroid-sparing agent needs in children with frequent relapses or steroid-dependent nephrotic syndrome.

METHODS

A retrospective multicenter cohort study was conducted by reviewing the medical records of children with idiopathic nephrotic syndrome treated between 2006 and 2023. Cox proportional regression analyzed prognostic factors for steroid-sparing agent requirements in children with frequent relapses or steroid-dependent nephrotic syndrome. The time-to-event analysis utilizing the Kaplan-Meier estimate examined the proportion of children needing steroid-sparing agents after diagnosis.

RESULTS

Medical records of 121 children (85 males) diagnosed with idiopathic nephrotic syndrome at a median age of 4.5 years (range 1.3-12.8) were reviewed over a median follow-up of 3.7 years (range 1.0-15.0). Time to subsequent relapse post-frequent relapses or steroid-dependent nephrotic syndrome diagnosis (at 3-month threshold) emerged as the sole significant predictor of steroid-sparing agent requirement, adjusted hazard ratio (aHR) = 2.26, 95% confidence interval (CI) 1.26-4.05. Kaplan-Meier analysis indicated that an earlier first relapse (< 3 months) led to earlier steroid-sparing agent requirement (log-rank p = 0.005). Children who relapsed within 3 months post-frequent relapses or steroid-dependent nephrotic syndrome diagnosis exhibited a higher frequency of relapses, a greater incidence of steroid-related adverse events, and were more likely to develop steroid dependency.

CONCLUSIONS

Early subsequent relapse following diagnosis of frequent relapses or steroid-dependent nephrotic syndrome was linked to earlier requirement of steroid-sparing agent therapy. Further prospective research is necessary to confirm this observation.

Overcoming Barriers to Drug Development in Children with CKD

Like all sick children, children with CKD need access to safe and effective medicines that have been formulated and examined specifically for them. Despite legislation in the United States and the European Union that either mandates or incentivizes programs for children, conducting trials to advance the treatment of children continues to prove to be a challenge for drug developers. This is also the case for drug development in children with CKD, where trials face challenges in recruitment and completion and where there remains a substantial time lag between initial approval of a medicinal product for use in adults and completion of studies that result in the addition of pediatric-specific labeling for the same indication. The Kidney Health Initiative commissioned a workgroup of diverse stakeholders ( https://khi.asn-online.org/projects/project.aspx?ID=61 ), including participants from the Food and Drug Administration and the European Medicines Agency, to think carefully through the challenges in drug development for children with CKD and how to overcome them. This article provides an overview of the regulatory frameworks in the United States and the European Union that govern pediatric drug development, the current landscape of drug development and approval for children with CKD, the challenges in conduct and execution of these drug trials, and the progress that has been made to facilitate drug development for children with CKD.

A Clinical Response-Adjusted Steroid Treatment Protocol for Children With Newly Diagnosed Idiopathic Nephrotic Syndrome

RATIONALE & OBJECTIVE

Prednisone protocols for children with idiopathic nephrotic syndrome (INS) are generally similar in dose and duration, despite wide variations in time to response. We assessed the feasibility of a novel clinical treatment protocol characterized by a shorter duration and lower cumulative dose for children with early clinical response.

STUDY DESIGN

Nonrandomized pilot clinical trial.

SETTING & PARTICIPANTS

The study population included 59 children with newly diagnosed INS treated between 2014 and 2019 who responded to treatment within 8 days.

INTERVENTION

The intervention group (n = 27) was treated with a response-adjusted protocol during which responders received an 8-week course of tapering doses of prednisone. The usual care group (n =32) was treated with the standard protocol (prednisone, 60 mg/m²/24 hours for 6 weeks, followed by 40 mg/m²/48 hours for 4 weeks, followed by a slow taper for a total of 24 weeks).

OUTCOME

Consent rate, cumulative prednisone dose, the development of frequently relapsing or steroid-dependent nephrotic syndrome (FRNS or SDNS, respectively), relapses per year, treatment with steroid-sparing therapies, and adverse effects of steroid therapy over 3 years of follow-up observation.

RESULTS

The consent rate was 88%. The mean cumulative steroid dose for the initial treatment was 70 mg/kg and 141 mg/kg (P < 0.001) in the intervention and usual care groups, respectively. None of the patients in the intervention group relapsed while on faster steroid taper down. The occurrence of FRNS and SDNS in the intervention group was not statistically different than in the usual care group, hazard ratios were 0.80 (95% CI, 0.37-1.73) and 0.61 (95% CI, 0.30-1.27), respectively. The proportions of relapse-free patients were similar (P = 0.5), and adverse steroid events did not differ between the groups.

LIMITATIONS

Lack of randomization and small sample size.

CONCLUSIONS

These findings demonstrate the feasibility of a shortened duration of steroid dosing for INS when patients demonstrate an initial clinical response to treatment. A larger study is needed to characterize the relative efficacy and toxicity of this novel treatment regimen.

FUNDING

This study received no funding.

TRIAL REGISTRATION

Registered at ClinicalTrials.gov with study number NCTO2649413.

Factors Predicting Short Term Outcome in Children With Idiopathic Nephrotic Syndrome: A Prospective Cohort Study

Objective

The objective of the article is to determine the risk factors associated with relapses in children with idiopathic nephrotic syndrome (INS).

Material and methods

Fifty-seven children with the first episode of INS were included and followed up prospectively for a minimum period of one year to identify the risk factors related to relapses. The study subjects were divided into early (less than eight days) and late (equal to or more than eight days) responder groups and were compared in terms of the number of days to achieve complete remission, time to first relapse, and the pattern of relapse at the last follow-up.

Results

Of the 57 children, 32 (56%) were male and 25 (44%) female. The mean age of the study cohort was 5.3 ± 3 years. Sixteen (55%) children with ages ranging from one to four years had a higher propensity to develop relapse, although the p-value (p=0.11) was not significant. Gender analysis did not reveal any significant correlation (p=0.32); however, a higher proportion of males (n=17; 63%) responded within eight days of starting steroids than female counterparts (n=10; 37%). Microscopic hematuria at the disease onset was seen in 12 (21%) children, and out of them, five (41.6%) remained in complete remission. The mean time to achieve complete remission was 8.1 ± 3.5 days, while the early responder group had delayed time to first relapse as compared to the late responders (3.1 ± 5.2 vs. 1.6± 3.8; p=0.21). Among all the study participants, a significant number of children (n=20; 51%) were in complete remission at their last follow-up visit. Baseline serum albumin, cholesterol, body mass index (BMI), and serum creatinine had no significant difference.

Conclusion

The delayed response to steroids and younger age at presentation can predict the time to first relapse and number of relapses in children with INS, respectively.

Optimizing the corticosteroid dose in steroid-sensitive nephrotic syndrome

The use of corticosteroids in the treatment of steroid-sensitive nephrotic (SSNS) syndrome in children has evolved surprisingly slowly since the ISKDC consensus over 50 years ago. From a move towards longer courses of corticosteroid to treat the first episode in the 1990s and 2000s, more recent large, well-designed randomized controlled trials (RCTs) have unequivocally shown no benefit from an extended course, although doubt remains whether this applies across all age groups. With regard to prevention of relapses, daily ultra-low-dose prednisolone has recently been shown to be more effective than low-dose alternate-day prednisolone. Daily low-dose prednisolone for a week at the time of acute viral infection seems to be effective in the prevention of relapses but the results of a larger RCT are awaited. Recently, corticosteroid dosing to treat relapses has been questioned, with data suggesting lower doses may be as effective. The need for large RCTs to address the question of whether corticosteroid doses can be reduced was the conclusion of the authors of the recent corticosteroid therapy for nephrotic syndrome in children Cochrane update. This review summarizes development in thinking on corticosteroid use in SSNS and makes suggestions for areas that merit further scrutiny.

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).

Prediction of Short- and Long-Term Outcomes in Childhood Nephrotic Syndrome

Introduction

It is unknown whether steroid sensitivity and other putative risk factors collected at baseline can predict the disease course of idiopathic nephrotic syndrome in childhood. We determined whether demographic, clinical, and family reported factors at presentation can predict outcomes in idiopathic nephrotic syndrome.

Methods

An observational cohort of 631 children aged 1 to 18 years diagnosed with idiopathic nephrotic syndrome between 1993 and 2016 were followed up until clinic discharge, 18 years of age, end-stage kidney disease (ESKD), or the last clinic visit. Baseline characteristics were age, sex, ethnicity, and initial steroid sensitivity. Of these, 287 (38%) children also reported any family history of kidney disease, preceding infection, microscopic hematuria, and history of asthma/allergies. The outcomes were complete remission after initial steroid course, need for a second-line agent, frequently relapsing disease, and long-term remission. The discriminatory power of the models was described using the c-statistic.

Results

Overall, 25.7% of children had no further disease after their initial steroid course. In addition, 31.2% developed frequently relapsing disease; however, 77.7% were disease-free at 18 years of age. Furthermore, 1% of children progressed to ESKD. Logistic regression modeling using the different baseline exposures did not significantly improve the prediction of outcomes relative to the observed frequencies (maximum c-statistic, 0.63; 95% confidence interval [CI], 0.59–0.67). The addition of steroid sensitivity did not improve outcome prediction of long-term outcomes (c-statistic, 0.63; 95% CI, 0.54–0.70).

Conclusions

Demographic, clinical, and family reported characteristics, specifically steroid sensitivity, are not useful in predicting relapse rates or long-term remission in idiopathic nephrotic syndrome. Further studies are needed to address factors that contribute to long-term health.

Eculizumab in STEC-HUS: need for a proper randomized controlled trial

Hemolytic uremic syndrome caused by Shiga toxin-producing E. coli (STEC-HUS) is often associated with a severe morbidity including neurological involvement and a mortality of 1-5%. Although STEC-HUS is often self-limited, improvement of treatment strategies is needed for cases with complications and, among others, plasma exchange/plasmapheresis and use of antibiotics have been advocated. With the availability of the complement blocker eculizumab, now a standard treatment of atypical HUS, several series have addressed its use in STEC-HUS, with variable response; randomized controlled trials are lacking.In this issue of Pediatric Nephrology, Pecheron et al. present a cohort of 33 pediatric patients with severe HUS treated with eculizumab. Neurological involvement was observed in 85% of the patients and 94% required dialysis. Most patients (55%) did not benefit from eculizumab and renal dysfunction as well as neurological sequelae did not resolve. In a subgroup of patients, however, rapid neurological improvement was described. In the post-hoc-defined group of patients with favorable outcome, there was a trend towards more sustained complement inhibition, although this finding was not significant compared to patients with an unfavorable outcome.Because multiple interventions were used and the study did not include any control group, future controlled studies are urgently needed to resolve the debate as to whether eculizumab can be an effective treatment for both prevention and treatment of complications in STEC-HUS.

Clinical and genetic heterogeneity in familial steroid-sensitive nephrotic syndrome

BACKGROUND

Familial steroid-sensitive nephrotic syndrome (SSNS) is a rare condition. The disease pathophysiology remains elusive. However, bi-allelic mutations in the EMP2 gene were identified, and specific variations in HLA-DQA1 were linked to a high risk of developing the disease.

METHODS

Clinical data were analyzed in 59 SSNS families. EMP2 gene was sequenced in families with a potential autosomal recessive (AR) inheritance. Exome sequencing was performed in a subset of 13 families with potential AR inheritance. Two variations in HLA-DQA1 were genotyped in the whole cohort.

RESULTS

Transmission was compatible with an AR (n = 33) or autosomal dominant (AD, n = 26) inheritance, assuming that familial SSNS is a monogenic trait. Clinical features did not differ between AR and AD groups. All patients, including primary (n = 7) and secondary steroid resistant nephrotic syndrone (SRNS), (n = 13) were sensitive to additional immunosuppressive therapy. Both HLA-DQA1 variations were found to be highly linked to the disease (OR = 4.34 and OR = 4.89; p < 0.001). Exome sequencing did not reveal any pathogenic mutation, neither did EMP2 sequencing.

CONCLUSIONS

Taken together, these results highlight the clinical and genetic heterogeneity in familial SSNS. Clinical findings sustain an immune origin in all patients, whatever the initial steroid-sensitivity. The absence of a variant shared by two families and the HLA-DQA1 variation enrichments suggest a complex mode of inheritance.

Predictors of frequent relapsing and steroid-dependent nephrotic syndrome in children

AIM

To determine the predictors of frequent relapses and steroid dependency in children with steroid-sensitive nephrotic syndrome.

MATERIAL AND METHODS

All children aged six months to 18 years with steroid-sensitive nephrotic syndrome registered in the nephrology clinic between 2003 and 2015 at a tertiary center who were followed up for at least 1year after onset were included in the study.

RESULTS

Two hundred seventy-seven patients with steroid-sensitive nephrotic syndrome who were followed up for at least 1 year from onset of disease were included. There were 157 infrequent relapsers and 120 frequent relapsers (frequent relapses and or steroid-dependent). Compared with infrequent relapsers, frequent relapsers had a significantly lower age at onset (51.53±40.42 vs. 61.97±40.66 months; p=0.035), lesser time for first relapse (time from the start of initial treatment to first relapse (8.65±11.99 vs. 23.46±24.05 months; p<0.001) and a higher number of relapses with infection (8.65±11.99 vs. 1.25±1.85; p<0.001). On multivariate logistic regression analysis, time for first relapse less than six months [OR: 3.93; 95% CI: (1.97-7.82)] and concomitant infection during relapses [OR: 1.82; 95% CI:(1.56-2.14)] were significant predictors of frequent relapses, and males were less likely to become frequent relapsers [OR: 0.48; 95% CI:(0.24-0.93)]. Kaplan-Meier analysis and the log-rank test also showed that a first relapse within six months was associated with frequent relapses. Age at onset and inadequate steroid therapy at onset did not determine frequent relapses.

CONCLUSION

Shorter time for first relapse and concomitant infection during relapses can predict future frequent relapses. These predictors may be useful to counsel patients, to follow them up more closely, and to develop better treatment protocols and relapse-specific interventions.

[Childhood steroid-dependent idiopathic nephrotic syndrome: Predictive factors for the need of immunosuppressive treatment]

BACKGROUND AND AIMS

More than half of the children with idiopathic nephrotic syndrome become steroid-dependent (or frequent relapsers) and will later require the use of complementary treatment aiming to reduce steroids' side effects and to limit the number of proteinuria relapses. It appears important to identify these children as early as possible in order to adapt their treatment. The aim of this study was to analyze the population of children, under 18 years of age, diagnosed between 1/01/2000 and 31/05/2015 with an idiopathic nephrotic syndrome and followed at the Montpellier University Hospital to search for criteria predictive of steroid-sparing agent use.

METHODS

In this retrospective study of children with idiopathic nephrotic syndrome, the exclusion criteria were primary steroid resistance and children with no proteinuria relapse after diagnosis.

RESULTS

Eighty-four children (54 boys) were included in this study. The mean follow-up duration was 5.5 years (0.75-16). The mean age at diagnosis was 4.6 years. Sixty-five children (77%) received at least one steroid-sparing agent during their follow-up, within a mean 10 months after diagnosis. In these patients, the first relapse of the disease occurred earlier when compared with the children who were maintained on steroid alone (4 months vs 7 months; P<0.001). The use of methylprednisolone pulses to obtain a remission, the cumulative dose of steroid treatment, and the number of proteinuria relapses were also significantly correlated with the use of complementary immunosuppressive therapy.

CONCLUSION

We found no predictive criteria of the use of steroid-sparing agents at diagnosis in our population of children. Nevertheless, with the steroid regimen used, the time within which the first proteinuria relapse occurred appears to be a significant criterion for the secondary use of a steroid-sparing agent. These data should be taken into account when choosing the treatment regimen.

New biologics in the treatment of rare glomerular diseases of childhood

Minimal change disease and focal segmental glomerulosclerosis are rare but important causes of end-stage kidney disease in children. Though their pathogenesis is still unclear, evidence of immune abnormalities provided the background for the use of immunosuppressive drugs, such as corticosteroids, calcineurin inhibitors, antiproliferative and alkylating agents. Unfortunately, these treatments fail to achieve a sustained remission in a significant portion of patients and are burdened by significant toxicities. Recent developments of new biologics, including anti-CD20 monoclonal antibodies rituximab and ofatumumab, offered the opportunity to selectively target immune cell subsets or activation pathways, leading to more effective and safer hypothesis-driven treatments.

Predictors of remission and relapse in idiopathic nephrotic syndrome: a prospective cohort study

BACKGROUND

Although most children with idiopathic nephrotic syndrome will respond to corticosteroid therapy, 80-90 % suffer one or more relapses.

METHODS

Using Cox proportional hazard models, we analyzed predictors of remission and relapse in 1-year follow-up data on children aged below 15 years with new-onset nephrotic syndrome.

RESULTS

Of 129 children, 107 achieved remission with corticosteroid therapy and 86 subsequently relapsed. Boys achieved remission more often than girls (adjusted hazard ratio [AHR] 1.52, 95 % confidence interval (CI) 1.02-2.3). Boys relapsed significantly more frequently than girls (AHR 1.77, 95 % CI 1.11-2.83) and were more likely to have frequently relapsing disease (AHR 3.3, 95 % CI 1.18-9.23). The risk of first relapse increased with the number of days to first remission (AHR 1.02, 95 % CI 1.01-1.04). The risk for a frequently relapsing course increased with a shorter time from remission to first relapse (AHR 0.92, 95 % CI 0.87-0.97).

CONCLUSIONS

In idiopathic nephrotic syndrome, boys are more likely to respond initially, more likely to relapse, and to be classified as having frequently relapsing nephrotic syndrome. A decrease in time from remission to first relapse predicts for a frequently relapsing course.