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

IPNA clinical practice recommendations for the diagnosis and management of children with steroid-sensitive nephrotic syndrome

Idiopathic nephrotic syndrome is the most frequent pediatric glomerular disease, affecting from 1.15 to 16.9 per 100,000 children per year globally. It is characterized by massive proteinuria, hypoalbuminemia, and/or concomitant edema. Approximately 85-90% of patients attain complete remission of proteinuria within 4-6 weeks of treatment with glucocorticoids, and therefore, have steroid-sensitive nephrotic syndrome (SSNS). Among those patients who are steroid sensitive, 70-80% will have at least one relapse during follow-up, and up to 50% of these patients will experience frequent relapses or become dependent on glucocorticoids to maintain remission. The dose and duration of steroid treatment to prolong time between relapses remains a subject of much debate, and patients continue to experience a high prevalence of steroid-related morbidity. Various steroid-sparing immunosuppressive drugs have been used in clinical practice; however, there is marked practice variation in the selection of these drugs and timing of their introduction during the course of the disease. Therefore, international evidence-based clinical practice recommendations (CPRs) are needed to guide clinical practice and reduce practice variation. The International Pediatric Nephrology Association (IPNA) convened a team of experts including pediatric nephrologists, an adult nephrologist, and a patient representative to develop comprehensive CPRs on the diagnosis and management of SSNS in children. After performing a systematic literature review on 12 clinically relevant PICO (Patient or Population covered, Intervention, Comparator, Outcome) questions, recommendations were formulated and formally graded at several virtual consensus meetings. New definitions for treatment outcomes to help guide change of therapy and recommendations for important research questions are given.

Current Understanding of Nephrotic Syndrome in Children

Nephrotic syndrome in children is mostly idiopathic in origin. About 90% of patients respond to corticosteroids; 80-90% have at least one relapse and 3-10% become corticosteroid resistant after the initial response. A kidney biopsy is seldom indicated for diagnosis except in patients with atypical presentation or corticosteroid resistance. For those in remission, the risk of relapse is reduced by the administration of daily low dose corticosteroids for 5-7 days at the onset of an upper respiratory infection. Some patients may continue having relapses through adult life. Many country-specific practice guidelines have been published, which are very similar with clinically insignificant differences.

Effectiveness of a Low Dose Prednisolone Regimen for Treatment of Relapses in Children with Steroid Sensitive Nephrotic Syndrome

Introduction

There may be a role of reducing the total steroid doses for the treatment of relapses of nephrotic syndrome in children with milder and more stable disease. The primary objective of this study was to compare the effectiveness of a low-dose prednisolone regimen with standard therapy for the treatment of relapses in steroid-sensitive nephrotic syndrome (SSNS) at the end of treatment, the secondary objectives being time to remission and sustained remission after 3 months.

Methods

This randomized controlled trial included a total of 40 children (20 in each group) with SSNS (presently infrequently relapsing course) and with a relapse. Both groups received prednisolone at a dose of 2 mg/kg/day until remission; subsequently, the patients in the study group received 1 mg/kg, and the control group participants received 1.5 mg/kg prednisolone on alternate days for 4 weeks. The patients were followed up till 3 months after stopping the therapy.

Results

The median (IQR) age of children enrolled was 7.5 (range: 5-9.65) years, and the age at onset of nephrotic syndrome was 4 (range: 2.3-5.5) years. The median time to achieve remission was 9 days (comparable in low dose vs. standard therapy group; P = 0.14). All patients were in remission at the end of therapy; 85% of patients were in the low-dose group and 90% in the standard therapy group after 1 month (P = 0.32). At the end of 3 months, 60% continued to be in remission in the low-dose group and 65% with standard therapy (P = 0.37). Hazard ratios for relapse at the end of 1, 2, and 3 months were 1.05, 1.08, and 1.13, respectively. Patients who were infrequently relapsing (79%) from the onset of nephrotic syndrome had higher remission rates at the end of 3 months (80% in the low-dose group vs. 76.9% in the standard therapy group). Hazard ratios for relapse in these patients at the end of 1, 2, and 3 months were 1.01, 1.03, and 1.08, respectively.

Conclusions

Lower doses of prednisolone can be used for the treatment of relapse of steroid sensitive nephrotic syndrome, with an infrequently relapsing course.

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.

Treatment of idiopathic nephrotic syndrome with two steroid dosing regimens - one-year observational study

Introduction

The aim of the study was to compare the first year of disease in children with idiopathic nephrotic syndrome (INS) treated according to two prednisone dosing regimens: a weight-based schedule (2 mg/kg/24 h in the 1^st month, 2 mg/kg/48 h in the 2^nd month, with dose tapering during the following 4 months), and a body surface area (BSA)-based schedule (60 mg/m²/24 h in the 1^st month, 40 mg/m²/48 h in the 2^nd month, with dose tapering during the following 4 months).

Material and methods

In 2 groups of children treated with weight- and BSA-based regimens (20 patients, 3.13 ±1.01 years, treated in 2010-2013 and 20 patients, 5.13 ±2.86 years, treated in 2014-2016) clinical and anthropometrical parameters, number of INS relapses, total prednisone dose (mg/kg/year), and steroid adverse effects were compared during the first year of disease.

Results

Children treated with the weight-based steroid regimen received a higher total annual prednisone dose (259.06 ±79.54 vs. 185.83 ±72.67 mg/kg/24 h, p = 0.004) and had a shorter (though not significantly) period without prednisone (38.25 ±55.83 vs. 75.90 ±73.06 days, p = 0.062) compared to patients treated with the BSA-based regimen. There was no difference in number of relapses between groups (2.20 ±1.64 vs. 1.60 ±1.67, p = 0.190) but more patients relapsed in the weight-based group (19/20 vs. 13/20, p = 0.044). No differences in Z-score values of height, weight, and body mass index (BMI) were observed. No steroid-related adverse events were noted except for arterial hypertension (4/20 vs. 5/20 patients, p = 1.000).

Conclusions

The BSA-based regimen of prednisone dosing in children with INS reduces exposure to steroids and risk of relapse, as well as increases days off steroids in the first year compared to the weight-based regimen with a high second-month dose.

Steroid Sensitive Nephrotic Syndrome: Revised Guidelines

JUSTIFICATION

Steroid sensitive nephrotic syndrome (SSNS) is one of the most common chronic kidney diseases in children. These guidelines update the existing Indian Society of Pediatric Nephrology recommendations on its management.

OBJECTIVE

To frame revised guidelines on diagnosis, evaluation, management and supportive care of patients with the illness.

PROCESS

The guidelines combine evidence-based recommendations and expert opinion. Formulation of key questions was followed by review of literature and evaluation of evidence by experts in two face-to-face meetings.

RECOMMENDATIONS

The initial statements provide advice for evaluation at onset and follow up and indications for kidney biopsy. Subsequent statements provide recommendations for management of the first episode of illness and of disease relapses. Recommendations on the use of immunosuppressive strategies in patients with frequent relapses and steroid dependence are accompanied by suggestions for step-wise approach and plan of monitoring. Guidance is also provided regarding the management of common complications including edema, hypovolemia and serious infections. Advice on immunization and transition of care is given. The revised guideline is intended to improve the management and outcomes of patients with SSNS, and provide directions for future research.

Steroid Sensitive Nephrotic Syndrome: Revised Guidelines

Justification

Steroid sensitive nephrotic syndrome (SSNS) is one of the most common chronic kidney diseases in children. These guidelines update the existing Indian Society of Pediatric Nephrology recommendations on its management.

Objective

To frame revised guidelines on diagnosis, evaluation, management and supportive care of patients with the illness.

Process

The guidelines combine evidence-based recommendations and expert opinion. Formulation of key questions was followed by review of literature and evaluation of evidence by experts in two face-to-face meetings.

Recommendations

The initial statements provide advice for evaluation at onset and follow up and indications for kidney biopsy. Subsequent statements provide recommendations for management of the first episode of illness and of disease relapses. Recommendations on the use of immunosuppressive strategies in patients with frequent relapses and steroid dependence are accompanied by suggestions for step-wise approach and plan of monitoring. Guidance is also provided regarding the management of common complications including edema, hypovolemia and serious infections. Advice on immunization and transition of care is given. The revised guideline is intended to improve the management and outcomes of patients with SSNS, and provide directions for future research.

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.

Efficacy of body weight vs body surface area-based prednisolone regimen in nephrotic syndrome

BACKGROUND

Prednisolone dosing regimen based on body surface area (BSA) or body weight (BW) in managing uncomplicated nephrotic syndrome (NS) has been a matter of controversy.

METHODS

In this parallel-arm randomized clinical trial, 60 children with uncomplicated NS in relapse were randomized to receive either of two regimens. Children of BW cohort received prednisolone (2 mg/kg/day) till remission (or 6 weeks for first episode); followed by 1.5 mg/kg on alternate days for 4 weeks (or 6 weeks for first episode). Children randomized for BSA cohort received prednisolone (60 mg/m²/day) till remission (or 6 week for first episode); followed by 40 mg/m² on alternate days for 4 weeks (or 6 weeks for first episode). The primary endpoint was 6-month relapse-free survival in the intention-to-treat population (clinical trial registry of India CTRI/2015/03/005655).

RESULTS

The 6-month relapse-free survival rates were similar for both BSA cohort 73.33% (22/30) and BW cohort 70% (21/30) (p = 1, OR 0.19, 95% CI 0.07-0.52). Requirement of cumulative steroid to achieve initial remission (96.1 ± 57.8 vs 63.58 ± 40.2 mg/kg, p = 0.014) and over 6-month study period (104.34 ± 50.82 vs 73.88 ± 42.95 mg/kg, p = 0.015) were significantly higher in BSA cohort in comparison to BW cohort. However, time taken in achieving remission during enrolment episode in both BSA and BW groups was comparable (7 ± 1.7 vs 6.9 ± 1.4 days, p = 0.81). While both treatments were well tolerated, the number of adverse events was one and half times as common in the BSA group than BW group (37 vs. 22 events).

CONCLUSIONS

In treating children with uncomplicated NS, both BSA and BW regimens were equally effective in achieving initial remission and maintaining disease remission. Due to fewer adverse events and lesser cumulative steroid exposure with BW based regimen, it may be considered as better option over BSA regimen.

CLINICAL TRIAL REGISTRY NAME

Clinical Trial Registry of India (CTRI/2015/03/005655).

Lower prednisone dosing for steroid-sensitive nephrotic syndrome relapse: a prospective randomized pilot study

Relapses of steroid-sensitive nephrotic syndrome are traditionally treated with prednisone 2 mg/kg/day or 60 mg/m²/day. Retrospective data support the use of lower doses. We designed a prospective randomized pilot study to investigate the efficacy of different doses in achieving remission of steroid sensitive nephrotic syndrome relapse. The cohort included 30 children with relapsed steroid sensitive nephrotic syndrome, mean age 6.3 ± 3 years and mean disease duration 2.2 ± 1.8 years. The children were randomized to receive 2, 1.5, or 1 mg/kg/day prednisone. The corresponding times to response, defined as the first of 3 consecutive days without proteinuria, were 7.2 ± 1.4, 10.2 ± 5.1, and 9 ± 3.3 days; the difference between the 1.5 and 2 mg/kg/day groups was statistically significant. One patient each in the 1 mg/kg/day and the 1.5 mg/kg/day groups failed to respond and were switched to 2 mg/kg/day, leading to a response after 3 and 10 days, respectively. Mean cumulative prednisone doses in the 3 groups were 45.5 ± 3.4, 42.7 ± 25.9, and 24.9 ± 7.4 mg/kg, respectively (P < 0.05).Conclusion: In the present study, treatment of childhood steroid sensitive nephrotic syndrome relapse with prednisone 1-1.5 mg/kg/day led to a significantly lower cumulative dose than the standard dose. Treatment with a lower dose may be equally safe and effective to the standard dose.What is Known:• Relapses of steroid-sensitive nephrotic syndrome are traditionally treated with standard-dose steroids.• Treatment with corticosteroids may have significant adverse effects mainly with long-term use.What is New:• Treatment of steroid sensitive nephrotic syndrome relapse with 1-1.5 mg/kg/day prednisone may lead to a significantly lower cumulative dose.• Treatment with a lower steroid dose may be as effective as the standard dose in achieving remission of steroid sensitive nephrotic syndrome relapse.

Equations to estimate prednisone dose using body weight

BACKGROUND

In the clinical practice, prednisone (PDN) dose in children is often prescribed using the patient weight, despite dose calculation using body surface area (BSA) is assumed to be preferable, because it parallels better with PDN metabolism in human subjects.

METHODS

Calculations based on body weight (W) carry the risk of underdosing, particularly in young children. Conversely, BSA estimation requires knowing the patient height, which is not always available, and more complex calculations.

RESULTS

To overcome these limitations, we have developed linear equations allowing approximating the BSA-based dose using only the patient weight in kilogram. To this end, we have used anthropomorphic data from 754 pediatric patients and have validated the proposed equations with a prospective cohort of 77 children with steroid sensitive nephrotic syndrome. The equation estimating a dose of 60 mg/m² was [2 × W + 8] and the equation estimating a dose of 40 mg/m² was [W + 11].

CONCLUSIONS

Both equations performed very well and predicted reliably the BSA-based dose with an average error of 3.4% and 2.2%, respectively.

Analysis of High Dose and Long-Term Prednisone Therapy on Trap 5B Level Change in Children with Steroid Sensitive Nephrotic Syndrome

Nephrotic syndrome is a condition which is characterized by protein leakage from the blood to the urine through glomeruli. It leads to hypoproteinemia and generalised oedema. Patients with nephrotic syndrome need high dose and long term glucocorticoid such as prednisone. High dose and long term glucocorticoid can increase bone resorption. Biological marker is a valuable tool to evaluate efficacy of therapy. TRAP 5B is a sensitive biological marker for bone resorption because it reflects the number of osteoclasts. TRAP 5B is not affected by renal dysfunction and food. It also has a low diurnal variation than other bone resorption marker. The aim of this study was to analyze the changes of TRAP 5B levels at induction and alternate phase in children with steroid sensitive nephrotic syndrome. This observational prospective study was conducted from May to October 2016. Venous blood samples obtained at 08.00-10.00 am. TRAP5B levels were measured before and after induction phase and after alternate phase using ELISA. Fifteen patients were included in this study (60% boys). Majority of their age was 6 - <12 years and 40% were dependent steroid NS. TRAP 5B serum levels in induction phase increased by 37.41%±56.22%. In alternate phase, TRAP 5B serum levels increased by 28.75%±66.55% compared to the induction phase. However, the level change of both phases were not significant. As a conclusion, TRAP 5B levels increased in induction and alternate phase after high dose and long-term prednisone treatment in nephrotic syndrome.

Should we stop dosing steroids per body surface area for nephrotics?

In this edition of Pediatric Nephrology, Vaishnavi Raman et al. have published an open-labeled randomized clinical trial of 100 children with idiopathic nephrotic syndrome who were allocated either a body weight- or body surface area-based prednisolone dosing for a duration of 12 weeks. The authors used Kaplan-Meier analysis for comparison of the time to remission. They also compared the relapse rate and found no difference. This editorial discusses the strengths of the current study as well some limitations. The inclusion of relapsing patients in the study protocol is problematic. The follow-up period of only 6 months forms another limitation. No subgroup analysis by age was performed. This editorial also highlights the lack of correlation between steroid dose and steroid exposure and the need for considering the age dependency (ontogeny) of drug disposition. Finally, the need for adherence to CONSORT criteria for reporting randomized controlled clinical trials is emphasized.

Weight-based dosing in medication use: what should we know?

BACKGROUND

Weight-based dosing strategy is still challenging due to poor awareness and adherence. It is necessary to let clinicians know of the latest developments in this respect and the correct circumstances in which weight-based dosing is of clinical relevance.

METHODS

A literature search was conducted using PubMed.

RESULTS

Clinical indications, physiological factors, and types of medication may determine the applicability of weight-based dosing. In some cases, the weight effect may be minimal or the proper dosage can only be determined when weight is combined with other factors. Medications within similar therapeutic or structural class (eg, anticoagulants, antitumor necrosis factor medications, P2Y12-receptor antagonists, and anti-epidermal growth factor receptor antibodies) may exhibit differences in requirements on weight-based dosing. In some cases, weight-based dosing is superior to currently recommended fixed-dose regimen in adult patients (eg, hydrocortisone, vancomycin, linezolid, and aprotinin). On the contrary, fixed dosing is noninferior to or even better than currently recommended weight-based regimen in adult patients in some cases (eg, cyclosporine microemulsion, recombinant activated Factor VII, and epoetin α). Ideal body-weight-based dosing may be superior to the currently recommended total body-weight-based regimen (eg, atracurium and rocuronium). For dosing in pediatrics, whether weight-based dosing is better than body surface-area-based dosing is dependent on the particular medication (eg, methotrexate, prednisone, prednisolone, zidovudine, didanosine, growth hormone, and 13-cis-retinoic acid). Age-based dosing strategy is better than weight-based dosing in some cases (eg, intravenous busulfan and dalteparin). Dosing guided by pharmacogenetic testing did not show pharmacoeconomic advantage over weight-adjusted dosing of 6-mercaptopurine. The common viewpoint (ie, pediatric patients should be dosed on the basis of body weight) is not always correct. Effective weight-based dosing interventions include standardization of weight estimation, documentation and dosing determination, dosing chart, dosing protocol, order set, pharmacist participation, technological information, and educational measures.

CONCLUSION

Although dosing methods are specified in prescribing information for each drug and there are no principal pros and cons to be elaborated, this review of weight-based dosing strategy will enrich the knowledge of medication administration from the perspectives of safety, efficacy, and pharmacoeconomics, and will also provide research opportunities in clinical practice. Clinicians should be familiar with dosage and administration of the medication to be prescribed as well as the latest developments.