Idiopathic Nephrotic Syndrome: Characteristics and Identification of Prognostic Factors

Positive impact of mobile educational platforms on blood glucose control in patients with nephrotic syndrome and steroid-induced diabetes mellitus: a randomized controlled study

OBJECTIVE

Steroid-induced diabetes mellitus (SDM) is a common complication in patients with nephrotic syndrome (NS) undergoing steroid therapy. Effective blood glucose control is critical for improving outcomes in these patients. This study evaluates the impact of mobile educational platforms on blood glucose control and patient adherence in patients with NS combined with SDM.

METHODS

A randomised controlled study was conducted involving 56 patients with NS and SDM at Shanxi People's Hospital between April 2019 and December 2020. Participants were recruited using convenient sampling and were randomly assigned to either the intervention group (n = 28) or the control group (n = 28). The control group received routine health management, whereas the experimental group was provided with health management via a mobile educational platform. Blood glucose levels (fasting glucose and postprandial blood glucose), self-management efficacy and patient adherence to treatment were assessed over a 6-month period.

RESULTS

The 56 participants included in the study had a mean age of 69.0 ± 10.5 years and an average diabetes duration of 7.2 ± 3.5 years. At the end of 6 months, the intervention group showed significant reductions in fasting blood glucose and postprandial blood glucose levels (P < 0.001). Self-management efficacy, assessed using the Diabetes Self-Efficacy Scale, improved significantly post-intervention (4.42 ± 0.53 vs. 4.15 ± 0.56, P = 0.020). Additionally, patient adherence to treatment improved by 25% in the intervention group compared with the control group.

CONCLUSION

The use of mobile educational platforms significantly resulted in better glycemic control and treatment adherence in the patients with NS and SDM compared to the control group. These findings suggest that integrating mobile health technologies into routine care can enhance disease management and optimise outcomes.

TRIAL REGISTRATION

The study was retrospectively registered "ISRCTN23135945" on 05/11/2024.

MicroRNA Expression and Target Prediction in Children with Nephrotic Syndrome

Background

Nephrotic syndrome is a common cause of kidney diseases in children. Many studies have examined the association of microRNAs playing potential roles in many pathophysiological functions. We investigated the expression pattern of the microRNAs miR-17-5P, miR-155p, miR-424-5p in children with steroid sensitive nephrotic syndrome (SSNS) and steroid resistance nephrotic syndrome (SRNS), along with the healthy subjects.

Materials and Methods

Total RNA was isolated from the urine samples from the three groups (SSNS n = 100, SRNS n = 100, and healthy control group n = 100). Bioinformatics tools such as miRWalk and miR-Tar link were used in predicting targets for the microRNAs. Online database and g profiler software are used to evaluate the targets based on the biological functions. The expression pattern for the candidate microRNAs was carried out using quantitative real time polymerase chain reaction (RT-PCR) equipment.

Results

miR-424 and miR-155 were upregulated in SRNS group while miR-17 was downregulated in SRNS group. miR-424-5p and miR-155p was up regulated in SRNS group while miR-17-5p was downregulated.

Conclusion

Combined analysis of gene expression along with studied candidate microRNAs can give better understanding of the pathogenesis of childhood nephrotic syndrome.

Multiomics Analysis of Plasma Proteomics and Metabolomics of Steroid Resistance in Childhood Nephrotic Syndrome Using a "Patient-Specific" Approach

Introduction

Nephrotic syndrome (NS) occurs commonly in children with glomerular disease and glucocorticoids (GCs) are the mainstay treatment. Steroid resistant NS (SRNS) develops in 15% to 20% of children, increasing the risk of chronic kidney disease compared to steroid sensitive NS (SSNS). NS pathogenesis is unclear in most children, and no biomarkers exist that predict the development of pediatric SRNS.

Methods

We studied a unique patient cohort with plasma specimens collected before GC treatment, yielding a disease-only sample not confounded by steroid-induced gene expression changes (SSNS n = 8; SRNS n = 7). A novel "patient-specific" bioinformatic approach merged paired pretreatment and posttreatment proteomic and metabolomic data and identified candidate SRNS biomarkers and altered molecular pathways in SRNS versus SSNS.

Results

Joint pathway analyses revealed perturbations in nicotinate or nicotinamide and butanoate metabolic pathways in patients with SRNS. Patients with SSNS had perturbations of lysine degradation, mucin type O-glycan biosynthesis, and glycolysis or gluconeogenesis pathways. Molecular analyses revealed frequent alteration of molecules within these pathways that had not been observed by separate proteomic and metabolomic studies. We observed upregulation of NAMPT, NMNAT1, and SETMAR in patients with SRNS, in contrast to upregulation of ALDH1B1, ACAT1, AASS, ENPP1, and pyruvate in patients with SSNS. Pyruvate regulation was the change seen in our previous analysis; all other targets were novel. Immunoblotting confirmed increased NAMPT expression in SRNS and increased ALDH1B1 and ACAT1 expression in SSNS, following GC treatment.

Conclusion

These studies confirmed that a novel "patient-specific" bioinformatic approach can integrate disparate omics datasets and identify candidate SRNS biomarkers not observed by separate proteomic or metabolomic analysis.

Genetic Variants of Interleukin-4 in Romanian Patients with Idiopathic Nephrotic Syndrome

Background and objectives: One of the most frequent glomerular diseases in the pediatric population is represented by the idiopathic nephrotic syndrome (INS). The exact mechanisms mediating the disease are still unknown, but several genetic factors have been studied for possible implications. Cytokines are considered to play a pivotal role in mediating INS disease progression, interleukin-4 (IL-4) exhibiting particular interest. The objective of this research project was to investigate the association between two IL-4 gene single-nucleotide polymorphisms (SNPs) and INS susceptibility as well as response to steroid therapy, in a group of Romanian children. Materials and Methods: In total, 75 patients with INS and 160 healthy controls of Romanian origin were genotyped for IL-4 rs2243250/−590C/T and rs2070874/−34C/T using real-time polymerase chain reaction. Association tests were performed using the DeFinetti program and Plink 1.07 software and p-values < 0.05 were considered statistically significant. Results: The analysis of INS patients and controls revealed a similar genotype distribution of the studied SNPs. The minor T alleles were less frequent in the INS group, but not statistically significant (p = 0.1, OR = 0.68 and p = 0.2, OR = 0.74). Regarding the response to steroids, a low frequency of 590*T allele in steroid-resistant patients (7.7%), compared with steroid-sensitive patients (14%) and controls (17.5%), was obtained, but the difference did not reach the statistical significance threshold. The same result was obtained for −34C/T SNP. Conclusions: This is the first study examining the relationship between the IL-4 gene and INS susceptibility conducted in a European population, and particularly in Romania. The investigated SNPs were found to not be associated with disease susceptibility or response to the steroid treatment of pediatric INS.

Genetic studies of nephrotic syndrome in Egyptian children

INTRODUCTION

Nephrotic syndrome (NS) might be caused by a kidney disorder or it can be a secondary disease. Untreated or resistant to treatment, NS stimulates glomerular damage that reduces the kidney function. This reduction leads to the end stage of renal failure. Therefore, it is very important to diagnose NS early, with the aim of inhibiting or lessening its associated morbidity and mortality.

METHODS

Gene polymorphism analysis for the three genes eNOS 27 bp VNTR, GSTP1 and IL-10(1082 G/A) were checked in 98 children with NS and 101 control subjects.

RESULTS

eNOS 27 bp VNTR genotypes and alleles are significantly different in the group of 98 children with NS compared to the 101 control subjects. The frequencies of ab and bb genotypes are significantly lower in patients than in the control group (ab: 17.2% vs. 22.8%; OR: 0.19; 95% CI: 0.06-0.58; p = 0.0026 & bb: 54.7% vs. 70.3%; OR: 0.19; 95% CI: 0.07-0.5; p = 0.0004). However, neither GSTP1 nor IL-10(1082 G/A) genotypes showed any significant difference in both groups.

CONCLUSIONS

eNOS 27 bp VNTR gene might be considered as an independent risk factor in the early prediction of nephrotic syndrome incidence, which may help prevent/reduce the occurrence of other complications associated with the late diagnosis and treatment of the disease.

CyTOF-Enabled Analysis Identifies Class-Switched B Cells as the Main Lymphocyte Subset Associated With Disease Relapse in Children With Idiopathic Nephrotic Syndrome

B cell depleting therapies permit immunosuppressive drug withdrawal and maintain remission in patients with frequently relapsing nephrotic syndrome (FRNS) or steroid–dependent nephrotic syndrome (SDNS), but lack of biomarkers for treatment failure. Post-depletion immune cell reconstitution may identify relapsing patients, but previous characterizations suffered from methodological limitations of flow cytometry. Time-of-flight mass cytometry (CyTOF) is a comprehensive analytic modality that simultaneously quantifies over 40 cellular markers. Herein, we report CyTOF-enabled immune cell comparisons over a 12-month period from 30 children with SDNS receiving B cell depleting therapy who either relapsed (n = 17) or remained stable (n = 13). Anti-CD20 treatment depleted all B cells subsets and CD20 depleting agent choice (rituximab vs ofatumumab) did not affect B cell subset recovery. Despite equal total numbers of B cells, 5 subsets of B cells were significantly higher in relapsing individuals; all identified subsets of B cells were class-switched. T cell subsets (including T follicular helper cells and regulatory T cells) and other major immune compartments were largely unaffected by B cell depletion, and similar between relapsing and stable children. In conclusion, CyTOF analysis of immune cells from anti-CD20 antibody treated patients identifies class-switched B cells as the main subset whose expansion associates with disease relapse. Our findings set the basis for future studies exploring how identified subsets can be used to monitor treatment response and improve our understanding of the pathogenesis of the disease.

Rituximab or plasmapheresis for prevention of recurrent focal segmental glomerulosclerosis after kidney transplantation: A systematic review and meta-analysis

BACKGROUND

Focal segmental glomerulosclerosis (FSGS) is one of the most common glomerular diseases leading to renal failure. FSGS has a high risk of recurrence after kidney transplantation. Prevention of recurrent FSGS using rituximab and/or plasmapheresis has been evaluated in multiple small studies with conflicting results.

AIM

To assess the risk of recurrence of FSGS after transplantation using prophylactic rituximab with or without plasmapheresis, and plasmapheresis alone compared to the standard treatment group without preventive therapy.

METHODS

This meta-analysis and systematic review were performed by first conducting a literature search of the MEDLINE, EMBASE, and Cochrane databases, from inception through March 2021; search terms included 'FSGS,' 'steroid-resistant nephrotic syndrome', 'rituximab,' and 'plasmapheresis,'. We identified studies that assessed the risk of post-transplant FSGS after use of rituximab with or without plasmapheresis, or plasmapheresis alone. Inclusion criteria were: Original, published, randomized controlled trials or cohort studies (either prospective or retrospective), case-control, or cross-sectional studies; inclusion of odds ratio, relative risk, and standardized incidence ratio with 95% confidence intervals (CI), or sufficient raw data to calculate these ratios; and subjects without interventions (controls) being used as comparators in cohort and cross-sectional studies. Effect estimates from individual studies were extracted and combined using a random effects model.

RESULTS

Eleven studies, with a total of 399 kidney transplant recipients with FSGS, evaluated the use of rituximab with or without plasmapheresis; thirteen studies, with a total of 571 kidney transplant recipients with FSGS, evaluated plasmapheresis alone. Post-transplant FSGS recurred relatively early. There was no significant difference in recurrence between the group that received rituximab (with or without plasmapheresis) and the standard treatment group, with a pooled risk ratio of 0.82 (95%CI: 0.47-1.45, I 2 = 65%). Similarly, plasmapheresis alone was not associated with any significant difference in FSGS recurrence when compared with no plasmapheresis; the pooled risk ratio was 0.85 (95%CI: 0.60-1.21, I 2 = 23%). Subgroup analyses in the pediatric and adult groups did not yield a significant difference in recurrence risk. We also reviewed and analyzed post-transplant outcomes including timing of recurrence and graft survival.

CONCLUSION

Overall, the use of rituximab with or without plasmapheresis, or plasmapheresis alone, is not associated with a lower risk of FSGS recurrence after kidney transplantation. Future studies are required to assess the effectiveness of rituximab with or without plasmapheresis among specific patient subgroups with high-risk for FSGS recurrence.

Comparison of Patients with Hospital-Recorded Nephrotic Syndrome and Patients with Nephrotic Proteinuria and Hypoalbuminemia: A Nationwide Study in Denmark

Background

Registry-based studies of nephrotic syndrome (NS) may only include a subset of patients with biochemical features of NS. To address this, we compared patients with laboratory-recorded nephrotic proteinuria and hypoalbuminemia to patients with hospital-recorded NS.

Methods

We identified adult patients with first-time hospital-recorded NS (inpatients, outpatients, or emergency-room visitors) in the Danish National Patient Registry and compared them with adults with first-time recorded nephrotic proteinuria and hypoalbuminemia in Danish laboratory databases during 2004-2018, defining the date of admission or laboratory findings as the index date. We characterized these cohorts by demographics, comorbidity, medication use, and laboratory and histopathologic findings.

Results

We identified 1139 patients with hospital-recorded NS and 5268 patients with nephrotic proteinuria and hypoalbuminemia; of these, 760 patients were identified in both cohorts. Within 1 year of the first record of nephrotic proteinuria and hypoalbuminemia, 18% had recorded hospital diagnoses indicating the presence of NS, and 87% had diagnoses reflecting any kind of nephropathy. Among patients identified with nephrotic proteinuria and hypoalbuminemia, their most recent eGFR was substantially lower (median of 35 versus 61 ml/min per 1.73 m²), fewer underwent kidney biopsies around the index date (34% versus 61%), and the prevalence of thromboembolic disease (25% versus 17%) and diabetes (39% versus 18%) was higher when compared with patients with hospital-recorded NS.

Conclusions

Patients with nephrotic proteinuria and hypoalbuminemia are five-fold more common than patients with hospital-recorded NS, and they have a lower eGFR and more comorbidities. Selective and incomplete recording of NS may be an important issue when designing and interpreting studies of risks and prognosis of NS.

Clinical significance of T lymphocyte subsets, immunoglobulin and complement expression in peripheral blood of children with steroid-dependent nephrotic syndrome/frequently relapsing nephrotic syndrome

OBJECTIVE

To investigate the clinical significance of T lymphocyte subsets, immunoglobulin and complement expression in the peripheral blood of children with steroid-dependent nephrotic syndrome/frequently relapsing nephrotic syndrome (SDNS/FRNS).

METHODS

A prospective study was conducted on 285 children with nephrotic syndrome (NS). Among the 285 patients, 187 children had steroid-sensitive nephrotic syndrome (SSNS) and 98 children had SDNS/FRNS according to their sensitivity to hormones. Meanwhile, 50 healthy children in the same period were selected as the control group. Serum albumin (ALB), blood urea nitrogen (BUN), serum creatinine (SCr), estimated glomerular filtration rate (eGFR), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), CD3+, CD4+, CD8+, immunoglobulin IgA, IgG, IgM and complement C3 and C4 were measured upon admission, and the content of urinary CD80 was also determined.

RESULTS

Compared with the control group, BUN, SCr, hs-CRP and IL-6 levels, urinary CD80, IgA, IgM and C3 in the SDNS/FRNS and SSNS groups were significantly higher, while ALB, eGFR, CD3+, CD4+, CD4+/CD8+, IgG and IgG/IgM were significantly lower (all P<0.05). Compared with the SSNS group, BUN, SCr, hs-CRP and IL-6 levels in the SDNS/FRNS group were significantly higher, while ALB and eGFR levels were significantly lower (all P<0.05). Compared with the SDNS/FRNS group, IgM in the SSNS group was significantly lower, while CD4+/CD8+, urinary CD80 and IgG/IgM were significantly higher (all P<0.001).

CONCLUSION

Renal function decline and inflammatory response existed in children with NS. CD3+, CD4+, CD4+/CD8+ and IgG/IgM in peripheral blood were decreased, while IgA, IgM, C3 and urinary CD80 were increased. Moreover, renal function decline, increase of inflammatory factors, decrease of IgG/IgM and CD4+/CD8+ were more obvious in the SDNS/FRNS group.

The role of real-time shear wave elastography in the diagnosis of idiopathic nephrotic syndrome and evaluation of the curative effect

PURPOSE

To evaluate the use of real-time shear wave elastography (SWE) in the assessment of renal elasticity and the efficacy of steroid treatment in adult idiopathic nephrotic syndrome (INS).

METHODS

This study included 120 patients with INS. Patients were divided into steroid-sensitive and steroid-resistant groups. Renal biopsy was performed. Thirty healthy subjects were recruited as controls. Young's modulus (YM) of the renal parenchyma was measured by SWE. The YM values in each group were compared using glomerular sclerosis index (GI) and renal interstitial fibrosis (RIF).

RESULTS

The YM values were significantly different between the INS and control groups, as well as between the steroid-sensitive and steroid-resistant groups (P < 0.05). Higher YM values were associated with steroid sensitivity. The area under the receiver operating characteristic curve for the YM value in the INS group vs. control group was 0.871 (95% CI 0.815-0.927) and in the steroid-resistant group vs. control, and steroid-sensitive groups was 0.836 (95% CI 0.765-0.908). The corresponding cut-off values were 7.96 and 10.73 m/s, with 81.7% and 86.0% sensitivities, 93.3% and 77.9% specificities, and Youden index 0.750 and 0.639, respectively. Spearman correlation analysis showed that the YM value in the renal parenchyma was positively correlated with GI (r = 0.631, P < 0.05) and RIF (r = 0.606, P < 0.05).

CONCLUSION

SWE technology is a potential method for non-invasive quantitative measurement of renal parenchyma stiffness to determine the pathological changes of INS renal parenchyma and evaluate the effectiveness of steroid therapy.

Recent advances in nanotechnology-based drug delivery systems for the kidney

The application of nanotechnology in medicine has the potential to make a great impact on human health, ranging from prevention to diagnosis and treatment of disease. The kidneys are the main organ of the human urinary system, responsible for filtering the blood, and concentrating metabolic waste into urine by means of the renal glomerulus. The glomerular filtration apparatus presents a barrier against therapeutic agents based on charge and/or molecular size. Therefore, drug delivery to the kidneys faces significant difficulties resulting in treatment failure in several renal disorders. Accordingly, different strategies have recently being explored for enhancing the delivery of therapeutic agents across the filtration barrier of the glomerulus. Nanosystems with different physicochemical properties, including size, shape, surface, charge, and possessing biological features such as high cellular internalization, low cytotoxicity, controllable pharmacokinetics and biodistribution, have shown promising results for renal therapy. Different types of nanoparticles (NPs) have been used to deliver drugs to the kidney. In this review, we discuss nanotechnology-based drug delivery approaches for acute kidney injury, chronic kidney disease, renal fibrosis, renovascular hypertension and kidney cancer.

[Ultrastructural study of podocyte alterations in non proliferative glomerulopathy]

Ultrastructural changes in podocytes are an important diagnostic and prognostic marker for nephropathies. However, the biomedical understanding of detected submicroscopic changes in podocytes remains controversial.

OBJECTIVE

To investigate the relationship between the ultrastructural changes of podocytes (fusion of cytopodia and denudation of the basement membrane as a result of their desquamation) with a number of clinical and laboratory indicators of kidney dysfunction in case of non-proliferative glomerulopathies (NPGP). Thirty-seven patients (23 men, 14 women) with NPGP, including 8 with focal segmental glomerulosclerosis (FSGS), 17 with membranous nephropathy (MN), and 12 with minimal change disease (MCD), were examined.

SUBJECT AND METHODS

All the patients underwent standard laboratory and instrumental studies: determinations of the levels of total serum cholesterol (mmol/l), total serum protein (g/l); serum albumin (g/l); CKD-EPI glomerular filtration rate (GFR) (ml/min/1.73 m²), and daily protein loss (g/day). Light optical changes were measured; completely sclerotic and/or focally segmentally sclerotic glomeruli were taken into account. Quantitative ultrastructural stereological analysis was carried out estimating the cytopodium width (CPW) and the degree of glomerular basement membrane denudation (GBMD) (%).

RESULTS

NPGP cases showed the largest number of sclerotic glomeruli in FSGS, which was accompanied by the lowest level of daily proteinuria and GFR. Quantitative values of CPW were associated with the level of daily protein loss (r=0.47; p < 0.05) and serum albumin (r=-0.57; p <0.05) in patients with nephrotic syndrome. In MN, the absolute value of CPW was larger than that in the other two patient groups. A correlation analysis of CPW and GBMD values among patients with NPGP revealed a statistically insignificant negative relation between these morphometric parameters. However, when a subgroup of patients with podocytopathies (only MCD and FSGS) was identified in the study group, this relationship was found to be significant (r=-0.54; p=0.012).

CONCLUSION

The patients with NPGP exhibited a relationship between the severity of nephrotic syndrome and proteinuria/hypoalbuminemia, on the one hand, and CPW, on the other. The established negative relationship between CPW and the percentage of GBMD in the subgroup of patients with podocytopathies may be due to the early stages of podocyte injury, which are accompanied by transient GBMD.