IgA vasculitis nephritis clinical course and kidney biopsy - national study in children

Correlation between the course of kidney injury and clinicopathology and prognosis of children with Henoch-Schönlein purpura nephritis

PURPOSE

Henoch-Schönlein purpura nephritis (HSPN) has a poor prognosis and variable pathophysiology. The present study aimed to analyze the kidney injury, clinicopathology, and prognosis of HSPN children.

METHODS

This retrospective study examined 249 children with HSPN. The patients' pathological and clinical data were collected. The patients were divided into the following groups according to the duration of their kidney injury: groups with disease duration of < 2 weeks, 2 weeks to 1 month, 1-2 months, 2-4 months, 4-6 months, and ≥ 6 months. The clinicopathological and prognostic relationships were examined between the groups.

RESULTS

We enrolled 249 children with HSPN (average age of 10.12 ± 3.01 years). There were 161 boys (64.66%) and 88 girls (35.34%). Altogether, 191 children (76.71%) developed kidney injury within 2 months. A total of 37 children (14.86%) showed recurrent renal damage after 6 months. Most patient groups exhibited hematuria and proteinuria, with type III pathology being the most common. During 2 weeks and 1 month of kidney injury, the acute pathology index peaked and then decreased; then, it increased again after 4 months as recurrence occurred. The chronic pathology index was the highest in the group with a disease duration of 2-4 months and it increased with increasing disease duration. The prognosis worsens with the disease duration.

CONCLUSION

Children with HSPN showed disease remission after a duration of 4-6 months. The acute and chronic pathology indexes peaked between 2 weeks to 1 month and 2-4 months, respectively. Patients with kidney injury occurring within a month had a much higher remission rate.

Laboratory Findings and Clinical Features in IgA Vasculitis: Identifying Predictors of Kidney Involvement and Disease Relapse in Pediatric Patients

Objective: This study aimed to identify clinical and laboratory predictors of kidney involvement and disease relapse in pediatric patients with IgA vasculitis (Immunoglobulin A vasculitis, IgAV). Materials and Methods: A retrospective cohort study was conducted on 173 children diagnosed with IgAV at the Children's Clinical Hospital of the Medical University of Warsaw between 2018 and 2022. Patients were categorized into groups based on renal involvement (IgAVN+ vs. IgAVN-) and disease recurrence. The analysis included demographic data, clinical manifestations, allergy history, presence of infection, duration of hospitalization, relapse occurrence, the interval between the first and second hospitalization, and laboratory markers. Results: Renal involvement was observed in 42% of cases, while disease recurrence occurred in 9.25% of patients. IgAVN+ patients were older, had longer hospital stays, and more frequently exhibited gastrointestinal symptoms, consistent with previous research. A history of allergic conditions was more prevalent in both the IgAVN+ and recurrence groups. An increase in IgA levels over time was associated with a higher risk of nephropathic development. Patients with recurrences had higher IgM levels and an elevated neutrophil-to-lymphocyte ratio (NLR) (p = 0.07). In the ROC (Receiver Operating Characteristic) analysis, a cutoff value of 1.67 for NLR (AUC 0.71; p = 0.0002; sensitivity 0.87; specificity 0.58) was identified as a risk factor for disease recurrence. Conclusions: Older age at disease onset, gastrointestinal involvement, and allergies are associated with renal involvement in pediatric IgAV. Immune dysregulation, reflected by elevated NLR and IgM, may contribute to disease recurrence. It is important to monitor changes in IgA levels over time, as an increase in IgA concentration is a risk factor for the development of nephropathy. Additionally, calculating the NLR is recommended, as it may indicate the probability of disease recurrence.

Outcome of immunosuppression in children with IgA vasculitis-related nephritis

BACKGROUND

Immunoglobulin A vasculitis with nephritis (IgAVN) is the most common vasculitis in children. Due to a lack of evidence, treatment recommendations are based on expert opinion, resulting in variation. The aim of this study was to describe the clinical presentation, treatment and outcome of an extremely large cohort of children with biopsy-proven IgAVN in order to identify prognostic risk factors and signals of treatment efficacy.

METHODS

Retrospective data were collected on 1148 children with biopsy-proven IgAVN between 2005 and 2019 from 41 international paediatric nephrology centres across 25 countries and analysed using multivariate analysis. The primary outcome was estimated glomerular filtration rate (eGFR) and persistent proteinuria at last follow-up.

RESULTS

The median follow-up was 3.7 years (interquartile range 2-6.2). At last follow-up, 29% of patients had an eGFR <90 mL/min/1.73 m2, 36% had proteinuria and 3% had chronic kidney disease stage 4-5. Older age, lower eGFR at onset, hypertension and histological features of tubular atrophy and segmental sclerosis were predictors of poor outcome. There was no evidence to support any specific second-line immunosuppressive regimen being superior to others, even when further analysing subgroups of children with reduced kidney function, nephrotic syndrome or hypoalbuminemia at onset. Delayed start of immunosuppressive treatment was associated with a lower eGFR at last follow-up.

CONCLUSION

In this large retrospective cohort, key features associated with disease outcome are highlighted. Importantly, there was no evidence to support that any specific immunosuppressive treatments were superior to others. Further discovery science and well-conducted clinical trials are needed to define accurate treatment and improve outcomes of IgAVN.

Clinical characteristics and risk factors for kidney involvement in children with immunoglobulin A vasculitis

BACKGROUND

Immumoglobulin A (IgA) vasculitis (IgAV), formerly known as Henoch-Schönlein purpura (HSP), is a self-limiting systemic vasculitis in children. Kidney involvement is associated with a long-term unfavorable outcome and can lead to significant morbidity. This study was conducted to describe the clinical and laboratory characteristics of childhood IgAV with kidney involvement and to identify risk factors associated with IgAV nephritis (IgAVN).

METHODS

This was an ambidirectional descriptive study of 77 children with IgAV. All demographic data, clinical features, and laboratory tests were collected from electronic medical records from January 2010 to December 2022. Risk factors for kidney involvement in IgAV were assessed using multivariate logistic regression. Kaplan-Meier survival analysis was used to calculate the time to commencement of kidney involvement.

RESULTS

Twenty-five children (32.4% of the IgAV patients) developed IgAVN. The common findings in IgAV with kidney involvement were microscopic hematuria (100%), nephrotic range proteinuria (44%), and non-nephrotic range proteinuria (40%). Multivariate logistic regression showed that age greater than 10 years (adjusted hazard ratio, AHR 4.66; 95% confidence interval, CI, 1.91-11.41; p = 0.001), obesity (body mass index, BMI, z-score ≥ +2 standard deviations, SDs) (AHR 3.59; 95% CI 1.41-9.17; p = 0.007), and hypertension at onset (AHR 4.78; 95% CI 1.76-12.95; p = 0.002) were associated significantly with kidney involvement. During follow up, most IgAV patients developed nephritis within the first 9 months.

CONCLUSION

Age greater than 10 years, obesity, and hypertension at presentation were predictive factors for IgAVN. Our study emphasized that IgAV patients with risk factors should be closely monitored for at least 1 year after the onset of the disease.

Recurrence of Henoch Schoenlein Purpura Nephritis in Children: A Retrospective Study

The aim of the study was to identify predictive patient characteristics for Henoch Schoenlein Purpura (HSPN) relapse in childhood HSPN. One hundred and thirty-five Chinese children with HSPN were enrolled in this study, mean age 10.25 ± 3.39 years. The pathology of HSPN was according to the International Study of Kidney Disease in Children criteria.(ISKDC); ISKDC II(mesangial proliferation (MP)) AND ISKDC III (MP with <50 % crescents).Recurrence of HSPN was observed in 66.3 % patients; male to female ratio (2:1)Statistically significant correlation existed between biopsy grade(p < 0.001), gender(p < 0.001),age ranges(p = 0.002) and treatment regimen (p < 0.001)in the frequency of recurrent HSPN episodes. We identified some significant predictors for HSPN relapse such as the severity of HSPN, adjunctive therapies administered to these patients,and close attention should be paid in patients between the ages 7 and 12 years old. In addition, the use of mycophenolate mofetil as an adjunctive therapy in the treatment of HSPN may reduce the frequency of HSPN relapse episodes in children.

Semiquantitative classification (SQC) and Oxford classifications predict poor renal outcome better than The International Study of Kidney Disease in Children (ISKDC) and Haas in patients with IgAV nephritis: a multicenter study

INTRODUCTION

Several histologic classifications are used in the evaluation of IgA vasculitis nephritis (IgAVN), however, to date, no studies have determined which one has the strongest association with the severity of IgAVN and, as a consequence, its outcomes.

MATERIALS AND METHODS

Patients included in the study were diagnosed with IgAV and IgAVN in seven tertiary university medical centers in Croatia, Italy and Israel. The International Study of Kidney Disease in Children (ISKDC), Haas, Oxford, and Semiquantitative classification (SQC) classifications were used in the analysis and description of renal biopsy. Time from biopsy to outcome evaluation was a statistically significant factor in outcome prediction that was used to define the base model, and was a covariate in all the tested models.

RESULTS

Sixty-seven patients were included in this study. The SQC classification proved to be the best one in outcome prediction, followed by the Oxford classification. The ISKDC and Haas classifications could not predict renal outcome. The Oxford parameters for mesangial hypercellularity and tubular atrophy, as well as the SQC parameters for cellular crescents showed an independent statistically significant contribution to outcome prediction. High level of twenty-four hour protein excretion was associated with a higher grade in the Oxford, SQC and ISKDC classifications. Endocapillary proliferation was positively associated with the Pediatric Vasculitis Activity Score (PVAS) at diagnosis, while tubular atrophy was negatively associated.

CONCLUSION

The SQC, followed by the Oxford classification were found to provide the best classifications of renal biopsy analysis in patients to predict the outcome in patients with IgAVN. Cellular crescents, mesangial hypercellularity and tubular atrophy showed significant contributions, indicating that active and chronic variables should be included in the estimation.

Endothelial Damage-dominant Nephritis Related to IgA Vasculitis after 11 Years' Use of Infliximab for Rheumatoid Arthritis

A 43-year-old Japanese woman with rheumatoid arthritis treated by infliximab and methotrexate for 11 years was admitted for proteinuria and purpura. A kidney biopsy revealed endothelial damage-dominant nephritis with IgA deposition. Infliximab and methotrexate were discontinued, and tocilizumab was started; however, proteinuria persisted. Therefore, tocilizumab was discontinued, and oral prednisolone and methylprednisolone pulse therapy were administered. After 6 months, urinary protein was less than 0.1 g/day, and purpura subsided. To our knowledge, this is the first case of endothelial damage-dominant nephritis related to IgA vasculitis involving the skin and kidney after long-term use of infliximab and methotrexate.

Bibliometric analysis of IgA vasculitis nephritis in children from 2000 to 2022

Background

IgA vasculitis Nephritis (IgAVN) is a kidney-damaging disease that occurs during the course of IgA vasculitis (IgAV) and is the most serious complication of IgAV. However, there is a lack of reports of bibliometric analysis of IgAVN in children. The purpose of this study is to conduct a bibliometric analysis of IgAVN in children from 2000 to 2022, to explore the current status and cutting-edge trends in the field of IgAVN in children, and to establish new directions for subsequent research.

Methods

Screening the literature in the field of IgAVN in children in the Web of Science Core Collection (WoSCC) from 2000 to 2022. Visual analysis of their annual publications, countries, institutions, authors, journals, keywords, and references were using CiteSpace5.8.R3 and VOSviewer1.6.18.

Results

A total of 623 publications were included in the study, since the beginning of 2014, there has been an overall increasing trend in the number of articles issued. The most prolific country and institution were China and Zhejiang University. The most frequently cited author was Coppo R, with 331 citations, who has made great contributions to IgAVN. Mao Jianhua, Lee JS and Wyatt Robert J were the most prolific authors, all with 9 articles. Pediatric Nephrology was the most published and cited journal. The highest burst strength keyword is IgA vasculitis, and the highest burst strength reference is Davin JC, 2014.

Conclusion

The research hotspots and trends predicted by the analysis of this study provide a reference for in-depth research in this field with a view to promoting the development of IgAVN research in children.

IgA vasculitis update: Epidemiology, pathogenesis, and biomarkers

Immunoglobulin A vasculitis (IgAV), formerly known as Henoch-Schönlein purpura, is the most common systemic vasculitis in children, characterized by diverse clinical manifestations with a wide spectrum ranging from isolated cutaneous vasculitis to systemic involvement. The incidence of IgAV is geographically and ethnically variable, with a prevalence in autumn and winter, suggesting a driving role that genetic and environmental factors play in the disease. Although IgAV has a certain degree of natural remission, it varies widely among individuals. Some patients can suffer from severe renal involvement and even progress to end-stage renal disease. Its pathogenesis is complex and has not been fully elucidated. The formation of galactose-deficient IgA1 (Gd-IgA1) and related immune complexes plays a vital role in promoting the occurrence and development of IgAV nephritis. In addition, neutrophil activation is stimulated through the binding of IgA to the Fc alpha receptor I expressed on its surface, resulting in systemic vascular inflammation and tissue damage. Starting from the epidemiological characteristics, this article will review the role of immunological factors such as Gd-IgA1, autoantibodies, circulating immune complexes, complement system, cellular immunization, and the contributions of environmental and genetic factors in the pathogenesis of IgAV, and conclude with the major biomarkers for IgAV.