The Clinicopathological Characteristics of Henoch-Schönlein Purpura Nephritis with Presentation of Nephrotic Syndrome

Towards better indications for kidney biopsy in adult IgA vasculitis: a clinical-laboratory and pathology correlation study

BACKGROUND

Indications for kidney biopsy in adult IgA vasculitis (IgAV) remain debated and there are very few studies on this subject. The aim of this study was to establish a correlation between renal histological and clinical-laboratory data.

METHODS

A retrospective multicenter study was conducted using three databases from French hospitals, gathered between 1977 and 2020. The study included 294 adult patients with IgAV who had undergone kidney biopsy assessed according to the prognostic "Pillebout classification". Different statistical models were used to test the correlations between histological and clinical-laboratory data: Cochran Armitage, ANOVA, Kruskal-Wallis and logistic regression.

RESULTS

The patients were primarily men (64%), with a mean age of 52 years. The main organs and tissues involved were: dermatological 100%, digestive 48% and rheumatological 61%. All had features of kidney involvement. The median serum creatinine was 96 µmol/L serum albumin 35 g/L, and C-reactive protein 28 mg/L. Of the patients, 86% (n = 254) had hematuria and median proteinuria was 1.8 g/day. The only statistically significant correlation between the pathological stages and the clinical-laboratory data was the presence of hematuria (p = 0.03, 66% class I to 92% class IV). In multivariate analysis, only albuminemia was associated with extracapillary proliferation (p = 0.02; OR 0.94) and only age was associated with stages 3-4 (p = 0.03; OR 1.02).

CONCLUSION

Our study suggests that there is no strict baseline correlation between renal pathology and clinical-laboratory data. Given the current knowledge, it seems relevant to recommend a kidney biopsy in the presence of significant and persistent proteinuria or unexplained kidney function decline.

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.

Intrinsic Kidney Pathology in Children and Adolescents Following COVID-19 Vaccination: A Systematic Review

Global COVID-19 vaccination programs for children and adolescents have been developed with international clinical trial data confirming COVID-19 mRNA vaccine safety and efficacy for the pediatric population. The impact of COVID-19 vaccination in the kidneys is thought to be explained by a complex immune-mediated relationship between the two, although the pathophysiological mechanisms of how COVID-19 vaccination potentially induces kidney pathology are not presently well known. Whilst intrinsic kidney pathologies following COVID-19 vaccination have been reported in adults, such cases are only being recently reported with greater frequency in children and adolescents. Conforming to the PRISMA checklist, we conducted a systematic review of the current literature to provide an overview on the range of intrinsic kidney pathologies that have been reported following COVID-19 vaccination in children and adolescents. All English language research articles published on or before 30 June 2022 reporting new-onset or relapsed intrinsic kidney pathology in children or adolescents (≤18 years) following COVID-19 vaccination were selected for qualitative analysis. Out of 18 cases from the 13 published articles selected, there were 10 cases of IgA nephropathy (1 case of rapidly progressive glomerulonephritis requiring acute hemodialysis), 5 cases of minimal change disease (MCD), 1 case of concurrent MCD/tubulointerstitial nephritis (TIN) and 2 cases of TIN. There is no indication currently to avoid vaccination, unless specific circumstances exist, as the benefits of COVID-19 vaccination far outweigh its risks. Concluding the findings from our systematic review based on preliminary evidence, potential adverse effects to the kidney from COVID-19 vaccination affects a small number of children and adolescents among the many who have been vaccinated. There remains good reason at present to support vaccination of children and adolescents with a greater morbidity status, such as those living with preexisting chronic kidney disease. Close observation of all children and adolescents receiving COVID-19 vaccination is recommended, particularly in those with preceding intrinsic kidney pathology to identify risks of relapsed disease.

Intrinsic Kidney Pathology Following COVID-19 Infection in Children and Adolescents: A Systematic Review

Introduction: COVID-19 infections resulting in pathological kidney manifestations have frequently been reported in adults since the onset of the global COVID-19 pandemic in December 2019. Gradually, there have been an increased number of COVID-19-associated intrinsic kidney pathologies in children and adolescents reported as well. The pathophysiological mechanisms between COVID-19 and the onset of kidney pathology are not fully known in children; it remains a challenge to distinguish between intrinsic kidney pathologies that were caused directly by COVID-19 viral invasion, and cases which occurred as a result of multisystem inflammatory syndrome due to the infection. This challenge is made more difficult in children, due to the ethical limitations of performing kidney biopsies to reach a biopsy-proven diagnosis. Although previous systematic reviews have summarized the various pathological kidney manifestations that have occurred in adults following acute COVID-19 infection, such reviews have not yet been published for children and adolescents. We describe the results of a systematic review for intrinsic kidney pathology following COVID-19 infection in children and adolescents. Methods: A systematic literature search of published data up until 31 October was completed through the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guidelines. Research articles reporting new-onset or relapsed intrinsic kidney pathology in children or adolescents (≤18 years) following acute COVID-19 infection were included for qualitative review. COVID-19 infection status was defined by a positive result from a RT-PCR, or nuclear antibody testing. Only full-text articles published in the English language were selected for review. Results: Twenty-nine cases from fifteen articles were included in the qualitative synthesis of this systematic review. Nephrotic syndrome, as an umbrella condition, appeared as the most frequently observed presentation (20 cases) with disease remission noted in all cases with steroid treatment. Other cases included numerous glomerulonephritides, such as acute necrotizing glomerulonephritis, MPO vasculitis and collapsing glomerulopathy, and thrombotic microangiopathies, such as aHUS. For patients with transplanted kidneys, T-cell-mediated rejection and mild tubular interstitial infiltration were noted following testing positive for COVID-19. There were no mortalities reported in any of the included cases, although two patients remained dialysis dependent at hospital discharge. Conclusion: This systematic review highlights the various intrinsic pathological kidney manifestations in children and adolescents as a result of acute COVID-19 infection. The clinical timeline and presentation of these cases support the mechanistic hypothesis between COVID-19 infection and the onset of intrinsic kidney pathologies within this context. The progressive introduction of vaccination programs for children and adolescents may hopefully reduce the severity of COVID-19-associated illnesses, and pathological kidney manifestations in this population.

Clinical predictive model for the 1-year remission probability of IgA vasculitis nephritis

PURPOSE

Early remission of Immunoglobulin A vasculitis nephritis (IgAVN) substantially affects its prognosis. In this work, a multivariate model to predict the 1-year remission probability of patients with IgAVN was developed on the basis of clinical laboratory data.

METHODS

Data of 187 patients with IgAVN confirmed by renal biopsy were retrospectively assessed. Least absolute shrinkage and selection operator regression analysis were conducted to establish a multivariate logistic regression model. A nomogram based on the multivariate logistic regression model was constructed for easy application in clinical practice. Concordance index, receiver operating characteristic (ROC) curves, decision curve analysis (DCA), and clinical impact curves (CIC) were used to evaluate the predictive accuracy and clinical value of this nomogram.

RESULTS

The predictive factors contained in the multivariate model included duration, gender, respiratory infection, arthritis, edema, estimated glomerular filtration rate, 24 h urine protein, uric acid, and renal ultrasound intensity. The area under the curves (AUC) of the nomogram in the training set and testing set were 0.814 and 0.822, respectively, indicating its good predictive ability. Moreover, the DCA curve and CIC revealed its clinical utility.

CONCLUSION

The developed multivariate predictive model combines the clinical and laboratory factors of patients with IgAVN and is useful in the individualized prediction of the 1-year remission probability aid for clinical decision-making during treatment and management of IgAVN.

The Efficacy of Tripterygium Glycosides Combined with LMWH in Treatment of HSPN in Children

Objective

This study aimed to explore the clinical efficacy and relevant mechanism of Tripterygium glycosides combined with low molecular weight heparin calcium (LMWH) in the treatment of Henoch–Schönlein purpura nephritis (HSPN) in children.

Methods

64 cases of children patients with HSPN treated at Qilu Hospital (Qingdao) from January 2015 to May 2020 were selected and randomly divided into the control group and the observation group and 32 cases in each group. Conventional medical treatment was applied in the two groups, besides which the control group was given LMWH while the observation group was given Tripterygium glycosides based on the control group. The clinical efficacy and the indexes of clinical symptoms of the two groups were compared. Immune globulin level, fibrinogen content (FIB), prothrombin time (PT), platelet level (PLT), and activated partial thromboplastin time (APTT) level of the two groups were compared before and after the treatment.

Results

The total effective rate in the observation group was significantly higher than that of the control group, and the recurrence rate in the observation group was lower than that in the control group. After treatment, urine red blood cell count and 24 h urine protein were obviously better than those of the control group. There was no statistically significant difference in PT between the two groups of children before and after treatment. The levels of PLT and FIB in the two groups of patients after treatment were significantly lower than before treatment, and the PLT levels in the observation group were lower than those in the control group.

Conclusion

The combination of Tripterygium glycosides and LMWH had good clinical effects in the treatment of children with HSPN, and it could improve the clinical symptoms, the mechanism of which might be related to the increase of PT, a decrease of PLT, and the improvement of coagulation function.

[Efficacy and safety of mycophenolate mofetil versus cyclophosphamide in the treatment of Henoch-Schönlein purpura nephritis with nephrotic-range proteinuria in children: a prospective randomized controlled trial]

OBJECTIVE

To study the efficacy and safety of mycophenolate mofetil (MMF) versus cyclophosphamide (CTX) in the treatment of children with Henoch-Schönlein purpura nephritis (HSPN) and nephrotic-range proteinuria.

METHODS

A prospective clinical trial was conducted in 68 pediatric patients who were admitted to the Department of Nephrology, Children's Hospital Affiliated to Capital Institute of Pediatrics and who were diagnosed with HSPN and nephrotic-range proteinuria from August 2016 to November 2019. The patients were randomly divided into two groups:MMF treatment (n=33) and CTX treatment (n=35). The two groups were compared in terms of complete remission rate, response rate (complete remission + partial remission), urinary protein clearance time, and adverse events.

RESULTS

At months 3, 6, and 12 of treatment, there was no significant difference in the complete remission rate and the response rate between the MMF treament and CTX treatment groups (P > 0.05). There was also no significant difference between the two groups in the urinary protein clearance time and the incidence rate of adverse events (P > 0.05).

CONCLUSIONS

MMF and CTX have similar efficacy and safety in the treatment of HSPN children with nephrotic-range proteinuria.

Global Glomerulosclerosis and Segmental Glomerulosclerosis Could Serve as Effective Markers for Prognosis and Treatment of IgA Vasculitis With Nephritis

Background: This study was aimed at investigating the clinical significance and curative effect of global glomerulosclerosis (GS) and segmental glomerulosclerosis (S) in adult-onset IgA vasculitis with nephritis (IgAV-N) patients since there was no consensus pathological grading method for adult IgAV-N. Methods: A total of 188 biopsy-proven IgAV-N patients were prospectively identified. Patients were separately assigned to GS0/GS1/GS2 group and S0/S1/S2 based on the scores of global glomerulosclerosis and segmental glomerulosclerosis (0% /0-15% />15%, respectively). Results: GS0, GS1, and GS2 occurred in 56.4, 29.2, and 14.4% of the adult-onset IgAV-N, respectively. Patients in GS2 group tended to have the most serious renal deterioration and the highest levels of blood pressure. IgAV-N patients were also divided into S0 group (64.4%), S1 group (20.7%), and S2 group (14.9%), where no obvious differences in baseline data were noted. K-M curves indicated that GS2 group had the worst renal outcome (P = 0.05) while there seemed to be no significant differences between GS0 group and GS1 group. In addition, no remarkable differences in primary outcome were found among S0 group, S1 group, and S2 group though the prognosis of S2 group tended to be the worst. However, the prognosis of S0/S1 group was markedly better than that of S2 (P = 0.04). The discrimination of poor prognosis could be improved by adding the pathological indicators of global glomerulosclerosis and segmental glomerulosclerosis. Most importantly, immunosuppressive treatment might be a superior alternative in IgAV-N patients without sclerosis scores or with lower level of sclerosis scores. But addition of immunosuppression was not recommended in patients with higher sclerosis scores. Conclusions: Global glomerulosclerosis and segmental sclerosis might be used for management and treatment of adult-onset IgAV-N.