Engineering antioxidant ceria-zirconia nanomedicines for alleviating podocyte injury in rats with adriamycin-induced nephrotic syndrome

BACKGROUND

Primary nephrotic syndrome (PNS) is characterized by edema, heavy proteinuria, hypoalbuminemia and hyperlipidemia. Moreover, podocyte injury is the key pathological change of PNS. Even though the pathophysiological etiology of PNS has not been fully understood, the production of excessive reactive oxygen species (ROS) plays an important role in the development and progression of the disease. Glucocorticoids are the first-line medications for patients with PNS, but their clinical use is hampered by dose-dependent side effects. Herein, we accelerated the rate of conversion from Ce4+ to Ce3+ by doping Zr4+ in ceria-zirconia nanomedicines to treat the PNS rat model by removal of ROS.

RESULTS

The engineered Ce0.7Zr0.3O2 (7CZ) nanomedicines significantly improved the ROS scavenging ability of podocytes at a very low dose, enabling effective inhibition of podocyte apoptosis and actin cytoskeleton depolymerization induced by adriamycin (ADR). Accordingly, podocyte injury was effectively alleviated in rat models of ADR-induced nephrotic syndrome, as confirmed by serum tests and renal tissue staining. Moreover, the mRNA sequencing assay revealed the protective molecular signaling pathways of 7CZ nanomedicines in podocytes.

CONCLUSION

7CZ nanomedicines were highly effective in protecting against ADR-induced podocyte injury in vitro and in vivo at a very low concentration.

Growth Parameters in Adolescents With Idiopathic Nephrotic Syndrome Diagnosed at the Age of 1-6 Years

OBJECTIVE

To determine the prevalence of impaired growth parameters (height and BMI z scores) among adolescents aged 10-19 years, with onset of idiopathic nephrotic syndrome between the age of 1 and 6 years.

METHODS

A cross-sectional study was conducted among adolescents aged 10-19 years with onset of idiopathic nephrotic syndrome between the age of 1-6 years, and under regular follow-up at our center. The data were retrieved for a 10-year period (2012-2022). The current weight, height and body mass index (BMI) were recorded and interpreted as per world Health Organization (WHO) growth standards.

RESULTS

116 adolescents [60 Frequently relapsing nephrotic syndrome (FRNS)/Steroid dependent nephrotic syndrome (SDNS), and 56 Steroid resistant nephrotic syndrome (SRNS)] patients were enrolled with median (IQR) age of 133 (120,168) months and age at disease onset of 48 (26,68) months. The proportion of children with overweight (BMI for age >1z and cushingoid features), obesity (BMI for age >2z), stunting (height for age (HFA) <2z), and severe stunting (HFA <3z) were 29 (25%), 3 (2.6%), 31 (26.7%), and 7 (6%), respectively. The median (IQR) cumulative steroid dose for FRNS/SDNS and SRNS group was 19986.96 (14597.1, 26181.96) mg/m2 and 14385 (10758.82, 21355.95) mg/m2, respectively (P=0.003).

CONCLUSION

The proportion of short stature and overweight was high among adolescents with nephrotic syndrome, emphasizing the need for measures to reduce steroid use and other measures to support growth.

Changes in bone turnover markers after discontinuing long-term glucocorticoid administration in children with idiopathic nephrotic syndrome: a multicenter retrospective observational study

BACKGROUND

Glucocorticoids affect bone turnover. Little is known about how bone turnover changes when glucocorticoids are discontinued following long-term administration.

METHODS

This retrospective observational study was conducted on the relationship between discontinuation of long-term administration of glucocorticoid and bone turnover markers (BTMs) in patients with childhood-onset idiopathic nephrotic syndrome. Serum bone alkaline phosphatase (BAP), intact procollagen type 1 N-terminal propeptide (P1NP), and tartrate-resistant acid phosphatase-5b (TRACP-5b) were evaluated as BTMs.

RESULTS

Thirty-eight pairs of BTMs at glucocorticoid administration and after discontinuation were analyzed in 29 patients. The median age at baseline was 12.4 (interquartile range, 9.0-14.5) years, and the median time from the onset of nephrotic syndrome was 5.9 (3.3-9.7) years. The mean period from prednisolone discontinuation to the measurement of BTMs after glucocorticoid discontinuation was 3.5 ± 1.0 months. Changes in BTMs after glucocorticoid discontinuation were modest when the daily prednisolone dose was < 0.25 mg/kg/day (ln BAP standard deviation [SD] score, p = 0.19; log intact P1NP SD score, p = 0.70; TRACP-5b, p = 0.95). When the daily prednisolone dose was ≥ 0.25 mg/kg/day, all BTMs increased significantly after glucocorticoid discontinuation (ln BAP SD score, p < 0.01; log intact P1NP SD score, p < 0.01; TRACP-5b, p < 0.01).

CONCLUSIONS

Decreased BTMs can rise within a few months of discontinuing long-term glucocorticoid administration. When the administered glucocorticoid dose is low, changes in BTMs may be small. A higher resolution version of the Graphical abstract is available as Supplementary information.

Health-related quality of life of children with first onset steroid-sensitive nephrotic syndrome

This study assessed HRQoL and emotional and behavioral difficulties (EBD) and associated variables in children with first onset SSNS. While relapsing steroid-sensitive nephrotic syndrome (SSNS) in children is associated with lower health-related quality of life (HRQoL), little is known about first onset. Four weeks after onset, children (2-16 years) and/or their parents who participated in a randomized placebo-controlled trial, completed the Pediatric Quality of Life Inventory 4.0 (PedsQL) and Strengths and Difficulties Questionnaire (SDQ) to measure HRQoL and EBD, respectively. Total and subscale scores and the proportion of children with impaired HRQoL (> 1 SD below the mean of the reference group) or SDQ clinical scores (< 10th and > 90th percentile) were compared to the Dutch general population (reference group). Regression analyses were used to identify associated variables. Compared to the reference group, children 8-18 years reported significantly lower total HRQoL, and physical and emotional functioning. A large proportion (> 45%) of these children had impaired HRQoL. There were no differences in HRQoL between children 2-7 years and the reference group, except for higher scores on social functioning (5-7 years). Similar proportions of SSNS and reference children scored within the clinical range of SDQ subscales. Age, sex, and steroid side-effects were negatively associated with HRQol and/or EBD.   Conclusion: This study showed that HRQoL and EBD are affected in children of different ages with first onset SSNS. This calls for more awareness from healthcare providers and routinely monitoring of HRQoL and EBD in daily clinical care to prevent worsening of symptoms.   Clinical trial registry: Netherlands Trial Register ( https://trialsearch.who.int/ ; NTR7013), date of registration: 02 June 2018. What is Known: •  Health-related quality of life (HRQoL) is lower and emotional and behavioral difficulties (EBD) is more affected in children with frequently-relapsing and steroid-dependent nephrotic syndrome. What is New: •  HRQoL and EBD are affected in children with first onset steroid-sensitive nephrotic syndrome compared to a reference group of the Dutch general population. • To what extent HRQoL and EBD are affected depends on the age of the patient.

Risk Factors for Relapse in Childhood Nephrotic Syndrome

Minimal change nephrotic syndrome is the most common cause of the glomerular disease in children. Despite its high initial response to corticosteroids, relapses are common leading to increased morbidity. Therefore, appraisal of common triggers of relapse becomes an imperative for successful management of childhood nephrotic syndrome. The objective of the study was to identify the risk factors for frequent relapse in childhood nephrotic syndrome. This descriptive cross-sectional study was conducted in the department of Paediatrics, Rangpur Medical College Hospital, Bangladesh from January 2013 to December 2014. A total of 60 patients with relapsed idiopathic childhood nephrotic syndrome fulfilling the selection criteria were enrolled into the study. Serum total protein, serum albumin and urine culture were done. The following potential risk factors for relapse were analyzed using Chi-square test: age at onset of NS, sex, socioeconomic status, atopy, short duration of initial therapy with steriod, serum total protein, serum albumin level and infection. Among 60 patients, short duration of therapy with steriod (<8 weeks) for first attack was significantly higher among frequent relapse (FRNS) cases compared with infrequent relapse (IFRNS) group (63% vs. 27.27%). FRNS group had initial brief period of remission of <6 months, (p=0.04). Difference in mean serum albumin and that of serum total protein between FRNS and IFRNS cases was (1.0±0.66 vs. 2.66±1.6gm/dl) (p<0.0001) and (3.5±1.2 vs. 6.5±2.12gm/dl) (p<0 .0001) respectively. This study concluded that short initial therapy with corticosteroid, brief duration of initial remission; low serum total protein and decreased serum albumin were the risk factors for frequent relapses.

Spectrum of Anemia in Indian children with Nephrotic Syndrome: a prospective observational study

We aimed to estimate the prevalence of anemia in children with nephrotic syndrome (NS), determine its etiology, and correlate severity with disease duration and response to steroids. This was a prospective cohort study carried from 15th July 2019-14th July 2021 at the pediatric nephrology clinic, of a teaching hospital in India. We screened children aged 3 months-18 years with NS for eligibility. We excluded those suffering from chronic kidney disease and, on haematinics. All children underwent investigations for evaluation of nephrotic syndrome and anemia. To define the clinical phenotype of nephrotic syndrome, the patients were classified as infrequent relapsers, frequent relapsers, steroid dependent and steroid resistant NS as per ISPN guidelines. Children were followed up at least for a period of one year to define their response to steroids. A total of 125 children were finally analysed for all treatment outcomes. Of 125, 37 (30%) children presented with the first episode of NS. Remaining 88 were follow up cases of NS. Of 125 children, 41 (33%) were found to be anemic as per the WHO criteria. Iron deficiency anemia was found in 21 (51%) children. Steroid resistance was twice more prevalent in the anemic group compared to the non-anemic group, 7.3% vs 4.8% respectively, however this difference was not statistically significant, p = 0.65. Anemic group had a trend of higher no. of children receiving antihypertensives compared to non-anemics (38 (93%) vs. 67 (80%), p = 0.07.

CONCLUSION

Iron deficiency anemia was the commonest cause of anemia and, anemia and need for anti-hypertensives to attain BP control and adequate proteinuria often coexisted in children suffering from nephrotic syndrome.

WHAT IS KNOWN

• Anemia is a significant complication in children suffering from nephrotic syndrome. • Cause of anemia in nephrotic syndrome is multifactorial.

WHAT IS NEW

• Iron deficiency anemia was the most common cause of anemia in Indian children with nephrotic syndrome. • Anemia and need for anti-hypertensives to attain adequate BP control and proteinuria often coexisted in children with nephrotic syndrome.

Single- versus Divided-Dose Prednisolone for the First Episode of Nephrotic Syndrome in Children: An Open-Label RCT

BACKGROUND

Early morning single-dose prednisolone has a hypothetical advantage of less hypothalamic-pituitary-adrenal (HPA) axis suppression, but lack of robust evidence has resulted in variation in practice, with divided-dose prednisolone still commonly used. We conducted this open-label randomized control trial to compare HPA axis suppression between single-dose or divided-dose prednisolone among children with first episode of nephrotic syndrome.

METHODS

Sixty children with first episode of nephrotic syndrome were randomized (1:1) to receive prednisolone (2 mg/kg per day), either as single or two divided doses for 6 weeks, followed by single alternative daily dose of 1.5 mg/kg for 6 weeks. The Short Synacthen Test was conducted at 6 weeks, with HPA suppression defined as postadrenocorticotropic hormone cortisol <18 µ mg/dl.

RESULTS

Four children (single=1 and divided dose=3) did not attend the Short Synacthen Test and were hence excluded from analysis. Remission was induced in all, and no relapse postremission was noted during the 6+6 weeks of steroid therapy. After 6 weeks of daily steroids, HPA suppression was greater in divided (100%) versus single dose (83%) ( P = 0.02). Time to remission and final relapse rates were similar, but for those children who relapsed within 6 months of follow-up period, time to first relapse was shorter for divided dose (median 28 versus 131 days) P = 0.002.

CONCLUSIONS

Among children with first episode of nephrotic syndrome, single-dose and/or divided-dose prednisolone were equally effective in inducing remission with similar relapse rates, but single dose had less HPA suppression and longer time to first relapse.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

CTRI/2021/11/037940.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_10_09_CJN0000000000000216.mp3.

First case report of PLA2R-related monotypic (IgG-κ positive) membranous nephropathy concurrent with leukocyte chemotactic factor 2 amyloidosis

BACKGROUND

Membranous nephropathy (MN) is a major pattern of nephrotic syndrome (NS) in adults. Some MN have secondary causes and some may be accompanied with other glomerular diseases. MN patients coexisting with amyloidosis are very rare, and mostly was polytypic MN. Herein, we describe the first report which identifying monotype PLA2R-MN (κ light chain) concurrent with leukocyte chemotactic factor 2 amyloidosis (ALECT2). This rare case highlights the importance of renal pathology for diagnosis.

CASE PRESENTATION

We describe a case of a 60-year-old male patient with persistent proteinuria and low serum albumin for nine months. No monoclonal component was revealed by serum and urine immunofixation electrophoresis but serum PLA2R antibody was positive. The patient was empirically treated with Leflunomide and Losartan, but edema was not improved. The diagnosis of renal pathology is PLA2R-related monotypic (IgG-κ positive) MN concurrent with ALECT2. Methylprednisolone, cyclosporine A and anticoagulant (rivaroxaban) were prescribed resulting in a complete remission of NS.

CONCLUSIONS

MN patients concurrent with ALECT2 presented massive proteinuria or NS. When nephrotic range proteinuria is present in ALECT2, it is important to consider that it may be due to a concomitant underlying nephropathy especially MN and treated according to MN will get good therapeutic effect.

Profound Changes in Functional Structure and Dynamics of Serum Albumin in Children with Nephrotic Syndrome: An Exploratory Research Study

Patients with nephrotic syndrome (NS) suffer from urinary loss of albumin. As a cause, previous studies focused on the glomerular filter rather than analyzing the molecular properties of albumin itself. Later one was initiated by clinical observations indicating unexplained molecular alterations of human serum albumin (HSA) in an NS pediatric patient. Therefore, we examined serum from eight pediatric patients with steroid-sensitive and -resistant NS and compared it with serum from healthy subjects as well as commercial HSA. We used dynamic and electrophoretic light scattering to characterize the protein size and effective surface charge and electron paramagnetic resonance spectroscopy to measure the local environment and binding dynamics of up to seven fatty acids associated with HSA. Our findings suggest that pronounced differences in binding behavior and surface charge of HSA could enhance their filtration through the GBM, leading to direct toxicity of HSA to podocytes.

Demographics and treatment of patients with primary nephrotic syndrome in Japan using a national registry of clinical personal records

The nationwide clinical features of Japanese patients with primary nephrotic syndrome (NS), including minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), or membranous nephropathy (MN), have not yet been reported. We collected the clinical personal records of patients with primary NS between 2015 and 2018 from the national registry organized by the Japanese Ministry of Health, Labour, and Welfare. Overall, the demographics, chronic kidney disease classification based on glomerular filtration rate and albuminuria, and treatment of 6036 patients were collected: 3394 (56.2%) with MCD, 677 (11.2%) with FSGS, 1455 (24.1%) with MN, and 510 (8.5%) with others. MN patients were older than MCD and FSGS patients (67 vs. 42 and 47 years, respectively). Steroid-dependent NS or frequently relapsing NS was found in 70.2%, 40.5%, and 24.6%, whereas steroid-resistant NS was found in 6.4%, 36.0%, and 37.9% of patients in the MCD, FSGS, and MN, respectively. The present oral prednisolone use (mean dose, mg/day) was 87.2% (21.2), 80.9% (20.0), and 77.5% (18.8) of patients in the MCD, FSGS, and MN, respectively. The national registry of clinical personal records of primary NS could provide an informative insight into the characteristics, clinical features, and treatment approaches for patients with primary NS in Japan.

Childhood nephrotic syndrome

Idiopathic nephrotic syndrome is the most common glomerular disease in children. Corticosteroids are the cornerstone of its treatment, and steroid response is the main prognostic factor. Most children respond to a cycle of oral steroids, and are defined as having steroid-sensitive nephrotic syndrome. Among the children who do not respond, defined as having steroid-resistant nephrotic syndrome, most respond to second-line immunosuppression, mainly with calcineurin inhibitors, and children in whom a response is not observed are described as multidrug resistant. The pathophysiology of nephrotic syndrome remains elusive. In cases of immune-mediated origin, dysregulation of immune cells and production of circulating factors that damage the glomerular filtration barrier have been described. Conversely, up to a third of cases of steroid-resistant nephrotic syndrome have a monogenic origin. Multidrug resistant nephrotic syndrome often leads to kidney failure and can cause relapse after kidney transplant. Although steroid-sensitive nephrotic syndrome does not affect renal function, most children with steroid-sensitive nephrotic syndrome have a relapsing course that requires repeated steroid cycles with significant side-effects. To minimise morbidity, some patients require steroid-sparing immunosuppressive agents, including levamisole, mycophenolate mofetil, calcineurin inhibitors, anti-CD20 monoclonal antibodies, and cyclophosphamide. Close monitoring and preventive measures are warranted at onset and during relapse to prevent acute complications (eg, hypovolaemia, acute kidney injury, infections, and thrombosis), whereas long-term management requires minimising treatment-related side-effects. A subset of patients have active disease into adulthood.

[Clinical characteristics and related factors analysis of adrenal crisis occurred in children with primary nephrotic syndrome]

Objective: To investigate the clinical characteristics and related factors of corticosteroid induced adrenal crisis (AC) in children with primary nephrotic syndrome (NS). Methods: Case control study. The case group included 7 children aged 1 to 18 years with NS combined with AC hospitalized in Peking University First Hospital from January 2016 to May 2021 (AC group). According to the ratio of case group: control group 1: 4, 28 children aged 1 to 18 years who were diagnosed with NS without AC during the same period were matched as controls (non-AC group). Clinical data were collected. The clinical characteristics of AC were described. The clinical parameters were compared between the 2 groups by t test, Mann-Whitney U test or Fisher's test. Receiver operating characteristic (ROC) curve was used to analyze the cutoff values of clinical parameters for prediction of AC. Results: The AC group included 4 boys and 3 girls aged 6.9 (4.6, 10.8) years. The non-AC group included 20 boys and 8 girls aged 5.2 (3.3, 8.4) years. All AC events occurred during the relapse of NS with infection. Seven children had gastrointestinal symptoms such as nausea, vomiting and abdominal pain. Six children had poor mental state or impaired consciousness. No significant differences in NS course, corticosteroid treatment course, corticosteroid type, steroid dosage, steroid medication interval, the proportion of gastroenteritis and fever existed between the two groups (all P>0.05). Compared with the non-AC group, the duration from the onset of the relapse of NS until hospitalization in the AC group was significantly shorter (0.2 (0.1, 0.6) vs. 1.0 (0.4, 5.0) month,U=25.50, P=0.005). The 24 h urinary total protein (UTP) level was significantly higher in the AC group (193 (135, 429) vs. 81 (17, 200) mg/kg, U=27.00,P=0.036) than the non-AC group. The serum albumin level in the AC group was significantly lower((13.1±2.1) vs. (24.5±8.7) g/L,t=-6.22,P<0.001) than the non-AC group. There were significantly higher total white blood cell counts ((26±9)×109 vs. (11±5)×109/L,t=4.26,P=0.004), percentage of neutrophils (0.71±0.08 vs. 0.60±0.19,t=2.56,P=0.017) and the proportion of children with C reactive protein level≥8 mg/L (3/7 vs. 0,P=0.005) in the AC group than in the non-AC group. ROC curve analysis showed that the cutoff value of 24 h UTP was 122 mg/(kg·d) with a sensitivity of 100.0% and specificity of 70.4%. The cutoff value of serum albumin was 17.0 g/L with a sensitivity of 100.0% and specificity of 82.1%. Conclusions: Gastrointestinal symptoms and poor mental state were prominent manifestations of AC in children with NS. High 24 h UTP level, low serum albumin level, high peripheral white blood cell counts, high neutrophils percentage, and high C-reactive protein level during the early stage of NS relapse may be related to the occurrence of AC in children with NS.

Vaccines and nephrotic syndrome: efficacy and safety

Vaccines represent the most important medical evolution in the last two centuries allowing prevention and formally eradication of a wide number of infectious diseases. Safety and effectiveness are main issues that still require an open discussion. A few clinical reports described a critical temporal relationship between vaccination and acute nephrotic syndrome, indirectly suggesting an association. For this review, the literature was reviewed to identify articles reporting associations of nephrotic syndrome with vaccines against a vast array of infectious diseases (including bacteria, virus and Sars-Cov-2). As specific aims, we evaluated effectiveness and safety in terms of occurrence of either "de novo" nephrotic syndrome in health subjects or "relapse" in those already affected by the disease. In total, 377 articles were found; 166 duplicates and 71 non-full text, animal studies or non-English language were removed. After excluding another 50 articles not containing relevant data on generic side effects or on relapses or new onset nephrotic syndrome, 90 articles met the search criteria. Overall, studies reported the effect of vaccines in 1015 patients, plus 4 nationwide epidemiologic investigations. Limited experience on vaccination of NS patients with measles, mumps, and rubella live attenuated vaccines does not allow any definitive conclusion on their safeness. VZV has been administered more frequently without side effects. Vaccines utilizing virus inactivated, recombinant, and toxoid can be utilized without risks in NS. Vaccines for influenza reduce the risk of infections during the pandemic and are associated with reduced risk of relapse of NS typically induced by the infection. Vaccines for SARS-CoV-2 (all kinds) offer a concrete approach to reduce the pandemic. "De novo" NS or recurrence are very rare and respond to common therapies.

Age and memory B cells at baseline are associated with risk of relapse and memory B-cell reappearance following anti-CD20 treatment in pediatric frequently-relapsing/steroid-dependent nephrotic syndrome

B-cell depleting anti-CD20 monoclonal antibodies, such as rituximab, have proven efficacy in children with frequently-relapsing/steroid-dependent nephrotic syndrome (FR/SDNS). However, drug-free remission is variable and specific baseline markers predictive of relapse after anti-CD20 treatment are still being defined. To clarify these, we performed a bicentric observational study in a large cohort of 102 children and young adults with FR/SDNS treated with anti-CD20 monoclonal antibodies (rituximab and ofatumumab). Sixty-two patients (60.8%) relapsed during a 24-month period (median [interquartile range] relapse-free survival, 14.4 months [7.9-24.0]). A lower risk of relapse was significantly associated with an older age (over 9.8 years, hazard ratio, 0.44; 95% confidence interval, 0.26-0.74) and a higher risk of relapse was significantly associated with higher circulating levels of memory B cells (1.14; 1.09-1.32) at time of anti-CD20 infusion, independent of time elapsed from onset, previous anti-CD20 treatment, type of administered anti-CD20 monoclonal antibodies, and previous or maintenance oral immunosuppression. Patients younger than 9.8 years at anti-CD20 infusion had a subsequent higher recovery of total, transitional, mature-naïve and memory B-cell subsets independent of previous anti-CD20 treatment and maintenance immunosuppression. Significantly, younger age and higher circulating levels of memory B cells at time of anti-CD20 infusion were also independently associated with the recovery of memory B cells by linear mixed-effects modelling. Thus, both younger age and higher circulating levels of memory B cells at time of infusion are independently associated with a higher risk of relapse and an earlier recovery of memory B cells following anti-CD20 treatment in children with FR/SDNS.

Japanese clinical practice patterns of primary nephrotic syndrome 2021: a web-based questionnaire survey of certified nephrologists

BACKGROUND

With the publication of the "Evidence-Based Clinical Practice Guideline for Nephrotic Syndrome 2020," we examined nephrologists' adherence to the recommendations of four of its clinical questions (CQs).

METHODS

This was a cross-sectional web-based survey conducted between November and December 2021. The target population comprised nephrologists certified by the Japanese Society of Nephrology who were recruited using convenience sampling. The participants answered six items regarding the four CQs about adult patients with nephrotic syndrome and their characteristics.

RESULTS

In total, 434 respondents worked in at least 306 facilities, of whom 386 (88.9%) provided outpatient care for primary nephrotic syndrome. Of these patients, 179 (41.2%) answered that they would not measure anti- phospholipase A2 receptor antibody levels in cases of suspected primary membranous nephropathy (MN) in which kidney biopsy was not possible (CQ1). Regarding immunosuppressants as maintenance therapy after relapse of minimal change nephrotic syndrome (CQ2), cyclosporine was the most common choice (290 [72.5%] and 300 [75.0%] of 400 respondents after the first and second relapses, respectively). The most common treatment for steroid-resistant cases of primary focal segmental glomerulosclerosis (CQ3) was cyclosporine (323 of 387, 83.5%). For the initial treatment of primary MN with nephrotic-range proteinuria (CQ4), corticosteroid monotherapy was the most common choice (240 of 403, 59.6%), followed by corticosteroid and cyclosporine (114, 28.3%).

CONCLUSION

Gaps in recommendations and practices regarding serodiagnosis and treatment of MN (i.e., CQ1 and 4) are observed, suggesting the need to address the barriers to their insurance reimbursement and the lack of evidence behind them.

Increased behavioural problems associated with corticosteroid use in children with nephrotic syndrome: a Southeast Asian perspective

Introduction

The study was performed to determine the psychological problems in children with idiopathic nephrotic syndrome (INS) while they were on steroid therapy, as compared to healthy children.

Methods

This prospective cohort study was conducted in a paediatric clinic of a tertiary hospital. Parents of the participants in the INS group and control group (comprising children without chronic illness) completed questionnaires using the Child Behavioural Checklist (CBCL). The CBCL measures a range of age-specific emotional and psychological problems, including internalising and externalising domains. Analyses of the CBCL scores between groups were done using Mann-Whitney U test.

Results

A total of 140 children were recruited with an equal number in the INS and control groups. There was a significant difference in the mean total CBCL scores between the INS group and the control group, specifically in the withdrawal, somatic, anxious and aggressiveness subdomains. Similar findings were demonstrated in correlation between total psychological problems and corticosteroid dosage. In the INS group, steroid dose and cushingoid features were found to have a significant positive association with internalising psychological problems.

Conclusion

Children with INS on corticosteroid treatment showed an increase in internalising and externalising scores, as compared to healthy children.

Genetic analysis and outcomes of Omani children with steroid-resistant nephrotic syndrome

BACKGROUND

Nephrotic syndrome (NS) is one of the most common kidney disorders seen by pediatric nephrologists and is defined by the presence of heavy proteinuria (>3.5 g/24 h), hypoalbuminemia (<3.5 g/dL), edema, and hyperlipidemia. Most children with NS are steroid-responsive and have a good prognosis following treatment with prednisolone. However, 10%-20% of them have steroid-resistant nephrotic syndrome (SRNS) and fail to respond to treatment. A significant proportion of these children progress to kidney failure.

METHODS

This retrospective study aimed to determine the underlying genetic causes of SRNS among Omani children below 13 years old, over a 15-year period and included 77 children from 50 different families. We used targeted Sanger sequencing combined with next-generation sequencing approaches to perform molecular diagnostics.

RESULTS

We found a high rate of underlying genetic causes of SRNS in 61 (79.2%) children with pathogenic variants in the associated genes. Most of these genetically solved SRNS patients were born to consanguineous parents and variants were in the homozygous state. Pathogenic variants in NPHS2 were the most common cause of SRNS in our study seen in 37 (48.05%) cases. Pathogenic variants in NPHS1 were also seen in 16 cases, especially in infants with congenital nephrotic syndrome (CNS). Other genetic causes identified included pathogenic variants in LAMB2, PLCE1, MYO1E, and NUP93.

CONCLUSION

NPHS2 and NPHS1 genetic variants were the most common inherited causes of SRNS in Omani children. However, patients with variants in several other SRNS causative genes were also identified. We recommend screening for all genes responsible for SRNS in all children who present with this phenotype, which will assist in clinical management decisions and genetic counseling for the affected families.

Rituximab-associated hypogammaglobulinemia in children with idiopathic nephrotic syndrome: results of an ESPN survey

BACKGROUND

There is paucity of information on rituximab-associated hypogammaglobulinemia (HGG) and its potential infectious consequences in children treated for idiopathic nephrotic syndrome (INS).

METHODS

A survey was distributed by the European Society Pediatric Nephrology to its members. It addressed the screening and management practices of pediatric nephrology units for recognizing and treating RTX-associated HGG and its morbidity and mortality. Eighty-four centers which had treated an overall 1328 INS children with RTX responded.

RESULTS

The majority of centers administered several courses of RTX and continued concomitant immunosuppressive therapy. Sixty-five percent of centers routinely screened children for HGG prior to RTX infusion, 59% during, and 52% following RTX treatment. Forty-seven percent had observed HGG prior to RTX administration, 61% during and 47% >9 months following treatment in 121, 210, and 128 subjects respectively. Thirty-three severe infections were reported among the cohort of 1328 RTX-treated subjects, of whom 3 children died. HGG had been recognized in 30/33 (80%) of them.

CONCLUSIONS

HGG in steroid-dependent/frequently relapsing nephrotic syndrome (SDNS/FRNS) children is probably multifactorial and can be observed prior to RTX administration in children with SDNS/FRNS. Persistent HGG lasting >9 months from RTX infusion is not uncommon and may increase the risk of severe infections in this cohort. We advocate for the obligatory screening for HGG in children with SDNS/FRNS prior to, during, and following RTX treatment. Further research is necessary to identify risk factors for developing both HGG and severe infections before recommendations are made for its optimal management. A higher resolution version of the Graphical abstract is available as Supplementary information.

Effect of Proprotein Convertase Subtilisin/Kexin Type 9 Inhibition on Podocytes in Mouse Nephrotic Syndrome

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is known to play a crucial role in dyslipidemia, and an increase in serum PCSK9 levels has also been reported in patients with nephrotic syndrome (NS). However, the specific effects of PCSK9 in kidney disease and the therapeutic potential of targeting PCSK9 in NS remain elusive. We thus investigated the effects of evolocumab (EVO) in mice with adriamycin (ADR)-induced NS. Male BALB/c mice were divided into the following 4 groups: Control, N = 11; EVO (monoclonal antibody for PCSK9), N = 11; ADR, N = 11; and ADR+EVO, N = 11. We also performed in vitro experiments using immortalized murine podocyte cells to validate the direct effects of PCSK9 on podocytes. EVO decreased urinary albumin levels and ameliorated podocytopathy in mice with ADR nephropathy. Further, EVO suppressed the Nod-like receptor protein 3 (NLRP3) inflammasome pathway in podocytes. PCSK9 expression upregulated CD36, a scavenger receptor of oxidized low-density lipoprotein (Ox-LDL), which in turn stimulated the absorption of Ox-LDL in vitro. EVO downregulated CD36 expression in podocytes both in vitro and in vivo. Immunofluorescence staining analysis reveals that CD36 and PCSK9 colocalized in the glomerular tufts of mice with ADR nephropathy. In the patients with focal segmental glomerulosclerosis, the CD36+ area in glomerular tufts increased compared with those diagnosed with minor glomerular abnormalities. This study revealed that EVO ameliorated mouse ADR nephropathy through the regulation of CD36 and NLRP3 inflammasome signaling. EVO treatment represents a potential therapeutic strategy for human NS.

Primary nephrotic syndrome relapse within 1 year after glucocorticoid therapy in children is associated with gut microbiota composition at syndrome onset

BACKGROUND

Children with primary nephrotic syndrome (PNS) who relapse after glucocorticoid therapy are shown to have a decreased total proportion of butyrate-producing bacteria in the gut at onset. Glucocorticoid treatment changes the gut microbiota composition. It is unclear whether gut microbiota at remission right after therapy and gut bacteria other than butyrate-producing bacteria are associated with PNS relapse.

METHODS

PNS relapse of paediatric patients within 1 year after glucocorticoid therapy was recorded. The gut microbiota composition, profiled with 16S rRNA gene V3-V4 region sequencing, was compared between relapsing and non-relapsing PNS children at onset before glucocorticoid treatment (preT group) and in PNS children at remission right after treatment (postT group), respectively.

RESULTS

The gut microbiota composition of postT children significantly differed from that of preT children by having lower levels of Bacteroides, Lachnoclostridium, Flavonifractor, Ruminococcaceae UBA1819, Oscillibacter, Hungatella and Coprobacillus and higher levels of Ruminococcaceae UCG-013 and Clostridium sensu stricto 1 group. In the preT group, compared with non-relapsing patients, relapsing patients showed decreased Blautia, Dialister and total proportion of butyrate-producing bacteria and increased Oscillibacter, Anaerotruncus and Ruminococcaceae UBA1819. However, relapsing and non-relapsing postT children showed no difference in gut microbiota composition.

CONCLUSIONS

PNS relapse-associated gut microbiota dysbiosis at onset, which includes alterations of both butyrate-producing and non-butyrate-producing bacteria, disappeared right after glucocorticoid therapy. It is necessary to study the association of the longitudinal changes in the complete profiles of gut microbiota after glucocorticoid treatment with later PNS relapse.

Biologics in steroid resistant nephrotic syndrome in childhood: review and new hypothesis-driven treatment

Nephrotic syndrome affects about 2-7 per 100,000 children yearly and accounts for less than 15% of end stage kidney disease. Steroids still represent the cornerstone of therapy achieving remission in 75-90% of the cases The remaining part result as steroid resistant nephrotic syndrome, characterized by the elevated risk of developing end stage kidney disease and frequently presenting disease recurrence in case of kidney transplant. The pathogenesis of nephrotic syndrome is still far to be elucidated, however, efficacy of immune treatments provided the basis to suggest the involvement of the immune system in the pathogenesis of the disease. Based on these substrates, more immune drugs, further than steroids, were administered in steroid resistant nephrotic syndrome, such as antiproliferative and alkylating agents or calcineurin inhibitors. However, such treatments failed in inducing a sustained remission. In last two decades, the developments of monoclonal antibodies, including the anti-CD20 rituximab and inhibitor of B7-1 abatacept, represented a valid opportunity of treatment. However, also the effectiveness of biologics resulted limited. We here propose a new hypothesis-driven treatment based on the combining administration of rituximab with the anti-CD38 monoclonal antibody daratumumab (NCT05704400), sustained by the hypothesis to target the entire B-cells subtypes pool, including the long-lived plasmacells.

IgG4-Related Membranous Nephropathy with Acute Nephrotic Syndrome During Successful Steroid Maintenance Treatment for Type 1 Autoimmune Pancreatitis

BACKGROUND Immunoglobulin G4 (IgG4)-related diseases (IgG4-RD) are systemic fibroinflammatory diseases that can develop asynchronously in multiple organs. IgG4-related kidney disease (IgG4-RKD) is generally characterized by tubulointerstitial nephritis but can also manifest as membranous nephropathy without tubulointerstitial nephritis. IgG4-related membranous nephropathy can present as a phenotype of systemic disorders, including autoimmune pancreatitis-associated diabetes mellitus; however, its clinical features remain unclear. CASE REPORT A 56-year-old Japanese man presented to our university hospital with bilateral edema of his lower legs. He had received a diagnosis of type 1 autoimmune pancreatitis and associated diabetes mellitus 16 months prior. He was successfully treated with oral glucocorticoids 25 mg/day of prednisolone as an initial dose, followed by titration down to a maintenance dose (5 mg/day), without recurrence of autoimmune pancreatitis. The pancreas showed atrophy and required basal-bolus insulin therapy owing to insulin insufficiency. Massive proteinuria and hypoalbuminemia with nephrotic syndrome on examination led to a renal biopsy to investigate the etiology and diagnosis of IgG4-RKD. Methylprednisolone and cyclosporine A were successfully administered to ameliorate the proteinuria and control systemic IgG4-RD with IgG4-related membranous nephropathy. CONCLUSIONS Ig4-RKD occurred despite maintenance treatment with prednisolone monotherapy and was controlled with methylprednisolone and cyclosporine A. Measurement of clinical parameters, including proteinuria, was important, and a renal biopsy finally established the diagnosis of IgG4-RKD. IgG4-RKD can present with progressive glomerular lesions and can be latent in cases diagnosed with diabetic kidney disease, particularly in patients with insulin insufficiency.

Exploration of the possible mechanisms of Ling Gui Zhu Gan decoction in nephrotic syndrome based on network pharmacology, molecular docking and molecular dynamics simulation

This study aimed to explore the possible mechanisms of Ling Gui Zhu Gan decoction (LGZGD) in the treatment of nephrotic syndrome (NS) using network pharmacology combined with molecular docking and molecular dynamics simulation. The active ingredients of LGZGD and their targets were retrieved from Traditional Chinese Medicine Systems Pharmacology Database and Swiss Target Prediction database. The NS targets were retrieved from Genecards, OMIM and Drugbank databases. Next, the intersecting targets of drug and disease were imported into the String database for protein-protein interaction network analysis, and the core targets were identified through topological analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed in the Metascape platform. Finally, molecular docking and molecular dynamics simulation were performed for further validation. The network analysis showed that 109 active ingredients of LGZGD were associated with 105 targets in NS. The key active ingredients (quercetin, kaempferol, naringenin, licochalcone A, formononetin, beta-sitosterol) and the core targets (IL6, AKT1, TNF, VEGFA, TP53, JUN, IL1B, CASP3, EGFR, and STAT3) were further identified. Enrichment analysis indicated that multiple biological processes and pathways, including AGE-RAGE, PI3K-Akt, JAK-STAT, and HIF-1 signaling pathways, might be regulated by LGZGD in the treatment of NS. Molecular docking and molecular dynamics simulation results further indicated that the key active ingredients of LGZGD could stably bind to the core targets through hydrogen bonding and hydrophobic interaction. This study demonstrates that the active ingredients of LGZGD may regulate multiple targets, biological processes and signaling pathways in NS. Our findings may provide a theoretical basis for further studies on LGZGD in the treatment of NS.

Hiding in plain sight: genetics of childhood steroid-resistant nephrotic syndrome in Sub-Saharan Africa

Steroid-resistant nephrotic syndrome (SRNS) is the most severe form of childhood nephrotic syndrome with an increased risk of progression to chronic kidney disease stage 5. Research endeavors to date have identified more than 80 genes that are associated with SRNS. Most of these genes regulate the structure and function of the podocyte, the visceral epithelial cells of the glomerulus. Although individuals of African ancestry have the highest prevalence of SRNS, especially those from Sub-Saharan Africa (SSA), with rates as high as 30-40% of all cases of nephrotic syndrome, studies focusing on the characterization and understanding of the genetic basis of SRNS in the region are negligible compared with Europe and North America. Therefore, it remains unclear if some of the variants in SRNS genes that are deemed pathogenic for SRNS are truly disease causing, and if the leading causes of monogenic nephrotic syndrome in other populations are the same for children in SSA with SRNS. Other implications of this lack of genetic data for SRNS in the region include the exclusion of children from the region from clinical trials aimed at identifying potential novel therapeutic agents for this severe form of nephrotic syndrome. This review underlines a need for concerted efforts to advance the genetic basis of SRNS in children in SSA. Such endeavors will complement global efforts at understanding the genetic basis of nephrotic syndrome.