Different histological classifications for Henoch-Schönlein purpura nephritis: which one should be used?

Clinicopathological features and prognosis of IgA vasculitis nephritis with nephrotic-range proteinuria in children

BACKGROUND

To investigate the clinical features, kidney pathology, treatment regimens, and clinical outcomes of IgA vasculitis nephritis (IgAVN) with nephrotic-range proteinuria in children.

METHODS

A retrospective review of children diagnosed with IgAVN between January 2019 and December 2022 was conducted. Participants were divided into two groups based on their urine protein/creatinine (UPCR) levels. Biodata, clinical characteristics, laboratory findings, pathologic features, treatment regimens, and outcomes were abstracted from case records and analyzed.

RESULTS

A total of 255 children were identified, 94 with nephrotic-range proteinuria (UPCR ≥ 200 mg/mmol) and 161 with non-nephrotic proteinuria (UPCR < 200 mg/mmol). Patients in the nephrotic-range proteinuria group were significantly younger and had worse grades of glomerular and acute tubulointerstitial injury compared to those in the non-nephrotic proteinuria group. Higher levels of blood urea nitrogen (BUN), D-dimer (DD), and fibrin degradation products (FDP), and lower levels of total protein (TP), albumin (ALB), urine creatinine (Cr), prothrombin time (PT), activated partial thromboplastin time (APTT), IgG, CD3 + cells, and CD4 + cells were found in patients in the nephrotic-range proteinuria group. Clinical outcome of patients with nephrotic-range proteinuria was significantly associated with ISKDC grading, proportion of glomerular crescents and severity of acute tubulointerstitial injury.

CONCLUSIONS

Children with nephrotic-range proteinuria exhibit more severe disordered immunologic function, hypercoagulability, glomerular and tubulointerstitial pathological damage, and have worse outcomes than those with lower proteinuria levels. Clinicians should pay great attention to the kidney injury and more extensive studies are required to identify optimal treatment regimens to improve outcomes in patients.

The efficacy of rituximab in the treatment of IgA vasculitis nephritis

The utility of Rituximab (RTX) for IgA vasculitis nephritis (IgAVN) is not well established. Up to now, we analysed the largest samples of IgAVN patients treated by RTX with a total of 41 retrieved subjects up to December 29, 2023 in the present systematic review. We assessed the clinical profiles, efficacy, and safety of RTX treatments. The present review showed that the renal function tended to be stabilized (P = 1.000) and urinalysis tended to normalize after RTX treatment with no serious adverse events reported. Moreover, 40% (16/40) of patients was freed use of glucocorticoid after RTX administration (P < 0.001). The remission rate was 92.7% (38/41) and complete remission rate was 46.3% (19/41) in IgAVN patients. Interestingly, 76.9% (10/13) of IgAVN child patients achieved complete remission when compared with 32.1% (9/28) of adult patients (P = 0.017). In summary, our results support the benefit of RTX therapy in IgAVN patients, especially children subjects.

Analysis of the influencing factors of abdominal Henoch-Schonlein purpura in children with gastrointestinal bleeding and the clinical value of PLR

OBJECTIVE

To identify the influencing factors of gastrointestinal bleeding in children with abdominal-type Henoch-Schonlein purpura (HSP) and to assess the diagnostic value of PLR (platelet-to-lymphocyte ratio).

METHODS

We retrospectively analyzed the medical records of 112 children with abdominal HSP admitted to Northwest Women's and Children's Hospital from April 2021 to May 2023. Among them, 62 cases with gastrointestinal bleeding constituted the bleeding group, while the other 50 cases without gastrointestinal bleeding comprised the non-bleeding group. We compared PLR and related routine blood indicators between the two groups. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors for gastrointestinal bleeding. HSP children with gastrointestinal bleeding were further categorized based on treatment efficacy, and the predictive value of PLR for treatment efficacy was analyzed.

RESULTS

The observation group exhibited significantly higher levels of WBC, NEU, PLT, MPV, C-reactive protein, and PLR, along with lower lymphocyte levels compared to the control group (all P < 0.05). Univariate analysis revealed associations between symptom onset, abdominal pain, vomiting, levels of WBC, NEU, LYM, PLT, PLR, C-reactive protein and gastrointestinal bleeding (all P < 0.05). Multivariate logistic analysis identified onset with abdominal pain, high WBC values, and elevated PLR ratios as risk factors for gastrointestinal bleeding. The ROC curve demonstrated an AUC of 0.914 for PLR in predicting gastrointestinal bleeding. Additionally, PLR was significantly lower in the good efficacy group compared to the poor efficacy group. The AUC of PLR in predicting treatment efficacy was 0.804, indicating high predictive value.

CONCLUSION

Elevated PLR may serve as a potential risk factor for gastrointestinal bleeding in children with abdominal-type allergic purpura. Monitoring changes in PLR could aid in diagnosis and improvements in treatment for this condition.

Navigating Adult-Onset IgA Vasculitis-Associated Nephritis

PURPOSE OF REVIEW

IgA vasculitis (IgAV), formerly Henoch-Schonlein purpura, is the most common systemic vasculitis in childhood. In adults, however, this condition is poorly understood, yet associated with more severe disease and poorer outcomes. This necessitates the need for early diagnosis and management.

SCOPE OF REVIEW

We describe the pathophysiology, clinical manifestations, and diagnosis of IgAV in adults. Poor outcomes are often due to the high frequency of glomerulonephritis in IgAV-IgA vasculitis-associated nephritis (IgAVN). We hence also aim to summarize the latest clinical data regarding treatment strategies in IgAVN. The diagnosis and differentiation in histology between IgAVN and IgA nephropathy (IgAN) remain a challenge. Review of treatment therapies: Pathological mechanisms between IgAVN and IgAN appear to be consistent between the two, and data from IgAN are often extrapolated to IgAVN. The role of various immunosuppression therapies remains controversial, and in this review, we will discuss immunosuppression use and highlight evidence surrounding emerging and promising novel therapies in IgAVN/IgAN. Our aim for this review is to guide future treatment strategies and direct future studies.

The Association of HMGB1 and RAGE Gene Polymorphisms with IgA Vasculitis

High-mobility group box 1 (HMGB1) is a pleiotropic cytokine that propagates inflammation by its extracellular action of interacting with the receptor for advanced glycation end products (RAGE). Both HMGB1 and RAGE play multiple roles in the pathogenesis of a variety of inflammatory and autoimmune diseases. We investigated the association of five single-nucleotide polymorphisms (SNPs) of the HMGB1 gene (rs1412125, rs2249825, rs1045411, rs1060348, rs41369348) and four SNPs of the RAGE gene (rs1800624, rs1800625, rs2070600, rs3134940) with the susceptibility and clinical features of paediatric patients with IgA vasculitis (IgAV), also known as Henoch-Schönlein's purpura. This case‒control study included 103 children with IgAV (experimental group) and 150 age-matched healthy individuals (control group). The strength of the association between different groups and alleles or genotypes of HMGB1 and RAGE was estimated using odds ratios (ORs) and 95% confidence intervals (CIs). The HMGB1 polymorphisms rs41369348, rs1045411, rs2249825 and rs1412125 were associated with the development of generalized purpuric rash, and rs1412125 was associated with IgAV nephritis (IgAVN). The RAGE polymorphism rs2070600 might be linked to the development of arthritis in IgAV patients. There was no statistically significant association between the analysed polymorphisms and susceptibility to IgAV. This is the first study to propose an association between several HMGB1 and RAGE polymorphisms and different phenotypes in the clinical course of IgAV in a paediatric population. Further research on other polymorphisms of HMGB1 and RAGE should be conducted in a larger number of patients.

The efficacy and safety of tacrolimus in treating refractory IgA vasculitis nephritis: a single-center retrospective study on 16 cases

Background

This study aimed to observe the efficacy and safety of tacrolimus in the treatment of refractory immunoglobulin A vasculitis nephritis (IgAVN).

Methods

Sixteen patients with IgAVN who had been previously treated with cyclophosphamide shock therapy at least five times, some of whom had also received mycophenolate but still had persistent proteinuria, were enrolled. The clinical and pathological data were collected and analysed.

Results

The average (mean ± standard deviation) age at the initial assessment for the group of 16 patients was 10 ± 2.7 years. Finally, at the end of their respective follow-up time point, 6 of the 16 patients achieved complete remission (37.5%), 5 achieved partial remission (31.2%), and 5 had no remission (31.2%). A significant difference was found in the median proteinuria before and after a 6-month course of tacrolimus treatment [19.2 (11.2, 31.9) vs 7.8 (4.3, 13.9) mg/kg/day] (P < .05). During the first 6 months of tacrolimus treatment, all patients' estimated glomerular filtration rate levels remained normal. The mean tacrolimus blood concentration was 6.0 ± 2.6 ng/mL. The median prednisone dosage was decreased from 10 mg/day to 5 mg/day, and prednisone was eventually stopped in three individuals. No drug-related adverse effects were observed during treatment.

Conclusions

Tacrolimus has demonstrated efficacy in increasing remission rates, significantly lowering urinary protein levels, and reducing steroid use in children with refractory IgAVN. Further research is required to investigate its optimal blood concentrations, long-term effects and renoprotective properties.

Huanglian Decoction treats Henoch-Schonlein purpura nephritis by inhibiting NF-κB/NLRP3 signaling pathway and reducing renal IgA deposition

Henoch-Schonlein purpura nephritis (HSPN) is a systemic vascular inflammatory disease. Huanglian Decoction (HLD) ameliorates renal injury in nephritis; however, the mechanism of action of HLD on HSPN has not been investigated. This study aimed to investigate the protective mechanism of HLD treatment in HSPN. The effects of HLD on HSPN biochemical indices, kidney injury and NF-κB/NLRP3 signaling pathway were analyzed by biochemical analysis, ELISA, HE and PAS staining, immunohistochemistry, immunofluorescence, and Western Blot. In addition, the effects of HLD on HSPN cells were analyzed. We found that HLD treatment significantly reduced renal tissue damage, decreased the levels of IL-17, IL-18, TNF-α, and IL-1β, and increased the levels of TP and ALB in HSPN mice. It also inhibited the deposition of IgA, IgG, and C3 in kidney tissues and significantly decreased the expression of IκBα, p-IκBα, NLRP3, caspase-1, and IL-1β in kidney tissues and cells. In addition, PMA treatment inhibited the above-mentioned effects of HLD. These results suggested that HLD attenuates renal injury, IgA deposition, and inflammation in HSPN mice and its mechanism of action may be related to the inhibition of the NF-κB/NLRP3 pathway.

Erythrocyte Glutathione S-Transferase Activity as a Sensitive Marker of Kidney Function Impairment in Children with IgA Vasculitis

IgA vasculitis (IgAV) is the most common childhood vasculitis. The main cause of morbidity and mortality in children with IgAV is nephritis (IgAVN), but the risk of its development, severity, and chronicity remain unclear. Erythrocyte glutathione S-transferase (e-GST) activity has been previously detected as a sensitive marker of kidney function impairment in several diseases. We spectrophotometrically assessed and correlated e-GST activity between 55 IgAV patients without nephritis (IgAVwN), 42 IgAVN patients, and 52 healthy controls. At disease onset, e-GST activity was significantly higher in IgAVN patients (median (interquartile range)) (5.7 U/gHb (4.4-7.5)) than in IgAVwN patients (3.1 U/gHb (2.2-4.2); p < 0.001), and controls (3.1 U/gHb (1.9-4.2); p < 0.001). Therewithal, there were no differences between the IgAVwN patients and controls (p = 0.837). e-GST activity was also significantly higher in the IgAVN patients than in the IgAVwN patients after 3 months (5.0 U/gHb (4.2-6.2) vs. 3.3 U/gHb (2.3-4.1); p < 0.001) and 6 months (4.2 U/gHb (3.2-5.8) vs. 3.3 U/gHb (2.1-4.1); p < 0.001) since the disease onset. Consistent correlations between e-GST activity and serum creatinine, estimated glomerular filtration rate (eGFR), and proteinuria levels were not detected. In conclusion, increased e-GST activity can serve as a subtle indicator of kidney function impairment in children with IgAV.

Involvement of M1-Activated Macrophages and Perforin/Granulysin Expressing Lymphocytes in IgA Vasculitis Nephritis

We investigated the polarisation of CD68+ macrophages and perforin and granulysin distributions in kidney lymphocyte subsets of children with IgA vasculitis nephritis (IgAVN). Pro-inflammatory macrophage (M)1 (CD68/iNOS) or regulatory M2 (CD68/arginase-1) polarisation; spatial arrangement of macrophages and lymphocytes; and perforin and granulysin distribution in CD3+ and CD56+ cells were visulaised using double-labelled immunofluorescence. In contrast to the tubules, iNOS+ cells were more abundant than the arginase-1+ cells in the glomeruli. CD68+ macrophage numbers fluctuated in the glomeruli and were mostly labelled with iNOS. CD68+/arginase-1+ cells are abundant in the tubules. CD56+ cells, enclosed by CD68+ cells, were more abundant in the glomeruli than in the tubuli, and co-expressed NKp44. The glomerular and interstitial/intratubular CD56+ cells express perforin and granulysin, respectively. The CD3+ cells did not express perforin, while a minority expressed granulysin. Innate immunity, represented by M1 macrophages and CD56+ cells rich in perforin and granulysin, plays a pivotal role in the acute phase of IgAVN.

[Clinical characteristics, pathology, and prognosis of children with diffuse endocapillary proliferative Henoch-Schönlein purpura nephritis]

OBJECTIVES

To investigate the clinical characteristics, pathology, and prognosis of children with diffuse endocapillary proliferative Henoch-Schönlein purpura nephritis (DEP-HSPN).

METHODS

A retrospective analysis was performed on the clinical, pathological, and prognosis data of 44 children with DEP-HSPN and 765 children without DEP-HSPN. The children with DEP-HSPN were diagnosed by renal biopsy in Jiangxi Provincial Children's Hospital from January 2006 to December 2021.

RESULTS

Among the 809 children with purpura nephritis, 44 (5.4%) had DEP-HSPN, with a mean age of (8±3) years, and there were 29 boys (65.9%) and 15 girls (34.1%). Compared with the non-DEP-HSPN group, the DEP-HSPN group had a significantly shorter time from onset to renal biopsy and a significantly higher proportion of children with respiratory infection or gross hematuria, and most children had nephrotic syndrome. The DEP-HSPN group had significantly higher levels of 24-hour urinary protein, urinary protein grading, microscopic hematuria grading, serum creatinine, and blood urea nitrogen and significantly lower levels of serum albumin and complement C3 (P<0.05). The DEP-HSPN group had a higher pathological grading, with predominant deposition of IgA in the mesangial area and capillary loops, and higher activity scores in the modified semi-quantitative scoring system (P<0.05). The Kaplan-Meier survival analysis showed that there was no significant difference in the renal complete remission rate between the two groups (P>0.05).

CONCLUSIONS

Children with DEP-HSPN have a rapid onset, severe clinical manifestations and pathological grading, and high activity scores in the modified semi-quantitative scoring system. However, most of the children with DEP-HSPN have a good prognosis, with a comparable renal complete remission rate to the children without DEP-HSPN.

Clinical features, treatment and outcome of pediatric patients with severe cutaneous manifestations in IgA vasculitis: Multicenter international study

OBJECTIVE

IgA vasculitis (IgAV) (formerly Henoch-Schönlein Purpura, HSP) rarely causes severe skin lesions in children. The purpose of the research was to determine whether severe skin manifestations were associated with a more severe disease course.

METHODS

Severe cutaneous manifestations were defined as presence of hemorrhagic vesicles, bullae, ulcerations and/or necroses. Data were collected retrospectively from 12 international tertiary university medical centers.

RESULTS

A total of 64 patients with the most severe skin changes in IgAV/HSP and median (Q1, Q3) age of 8.08 (5.08, 11.92) years at the disease onset were compared with 596 IgAV/HSP patients without these manfiestations and median (Q1, Q3) age of 6.33 (4.50, 8.92) years. The patients with severe cutaneous manifestations were older in comparison to other patients with IgAV/HSP (p<0.001), they developed nephritis more frequently (40.6% vs. 20.6%, p = 0.001) with worse outcome of renal disease (p = 0.001). This group of patients also had higher frequencies of severe gastrointestinal complications like hematochezia, massive bleeding and/or intussusception (29.3% vs. 14.8%, p<0.001). d-dimer concentrations were significantly higher in these patients (4.60 mg/L vs. 2.72 mg/L, p = 0.003) and they had more frequent need for treatment with systemic glucocorticoids (84.4% vs. 37.2%, p<0.001) in comparison with the control group. Further multivariate analysis showed that severe cutaneous changes were associated with higher risk of developing nephritis [OR=3.1 (95%CI 1.04-9.21), p = 0.042] and severe gastrointestinal complications [OR=3.65 (95%CI 1.08-12.37), p = 0.038].

CONCLUSION

Patients with IgAV/HSP and severe skin manifestations had a more severe clinical course and more frequently required glucocorticoids compared to classic IgAV/HSP patients.

ASSOCIATION BETWEEN HIGH MOBILITY GROUP BOX 1 PROTEIN GENE (rs41369348) POLYMORPHISM AND IMMUNOGLOBULIN A VASCULITIS IN CHILDREN

Immunoglobulin A vasculitis (IgAV) or Henoch-Schönlein purpura is the most prevalent systemic small vessel vasculitis in childhood. High mobility group box 1 protein (HMBG1) is a pleiotropic cytokine that functions as a pro-inflammatory signal, important for the activation of antigen-presenting cells and propagation of inflammation. HMGB1 is implicated in the pathophysiology of a variety of inflammatory diseases. The aim of this study was to investigate the role of single nucleotide polymorphism rs41369348 for HMGB1 gene in the susceptibility and clinical features of patients meeting the classification criteria for IgAV. DNA was extracted from blood cells of 76 children with IgAV and 150 age-matched healthy controls. Clinical data and laboratory parameters were collected for all IgAV patients. Although there was a higher frequency of heterozygous A/delA genotype of this gene polymorphism in IgAV group as compared with control group, no genotype difference was observed between these two groups. No statistically significant genotype differences were disclosed when patients with different IgAV clinical features were compared. In conclusion, in this study, polymorphism rs41369348 for HMGB1 was not associated with increased susceptibility to childhood IgAV, its severity or different clinical manifestations.

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.

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.

A modern approach to the morphological assessment of nephritis in Henoch–Schonlein purpura (IgA-vasculitis)

The authors analyzed clinical and morphological correlations between the manifestations and outcome in nephritis with Henoch– Schönlein purpura and assessed the effect of morphological data on achieving remission as per ISKDC, SQC, MEST-C classification.Patients and methods. 32 patients with nephritis in Henoch–Schönlein purpura (15 girls and 17 boys) were enrolled into retrospective longitudinal single-center study, median of primary admission to the nephrological department was 9.0 y. o. [5; 12 y.]. Clinical features of the onset (age, form of onset, glomerular filtration rate, daily proteinuria, hematuria, serum IgA level) and the course of the disease were analyzed in all children. The morphological data were assessed using such morphological classifications as ISKDC, SQC, MEST-C. A search for statistically significant relationships between clinical and morphological data and a comparative analysis of the influence of each morphological classification on the achievement of remission were carried out.Results. The sum of the SQC scores had a statistically significant effect on the outcome (p=0.006): in patients with complete remission, on average, 4 points were obtained, patients who did not achieve remission had 2 points more. When assessing the likelihood of detecting remission depending on the total score of the Oxford scale using the ROC-analysis, a statistically significant model was obtained (p=0.012). If the total MEST-C score was less than or equal to 3, remission was predicted (=0.032). The sensitivity and specificity of the method were both 75%.Conclusions. The practical application of the Oxford MEST-C classification and the new semi-quantitative SQC classification in comparison with the ISKDC classification for children with nephritis in Henoch–Schönlein purpura is promising for predicting an unfavorable renal outcome.

Diagnostic and Management Strategies of IgA Vasculitis Nephritis/Henoch-Schönlein Purpura Nephritis in Pediatric Patients: Current Perspectives

IgA vasculitis (IgAV) or Henoch-Schönlein purpura (HSP) is the most common vasculitis in children, and nephritis (IgAVN or HSPN) is the most important and only chronic manifestation of the disease. Despite this, there are no diagnostic criteria and we rely on the European League Against Rheumatism/Paediatric Rheumatology International Trials Organization/Paediatric Rheumatology European Society-endorsed Ankara 2008 classification criteria in our daily practice. Basic investigations that should be done in every patient with IgAVN include blood pressure measurement, estimated glomerular filtration rate and urinalysis. Kidney biopsy is still the gold standard for the diagnosis of IgAVN since noninvasive confirmation of nephritis is still pending. According to the Single Hub and Access point for pediatric Rheumatology in Europe (SHARE) recommendations, the first-line treatment for with mild forms of IgAVN is oral glucocorticoids, for patients with moderate IgAVN parenterally administrated glucocorticoids in pulsed doses, while initial treatment for patients with the most severe forms of IgAVN include pulsed doses of glucocorticoids in combination with intravenous cyclophosphamide pulses. New therapeutic options are currently being tested, aiming to reduce the production of galactose-deficient IgA₁ and autoantibodies or suppress the alternative or lectin complement pathway and blocking mesangial cell activation.

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.

Vasculitis and Kidney Disease

Pediatric vasculitis is a complex group of disorders that commonly presents with multisystem involvement. Renal vasculitis can be isolated to the kidneys or can occur as part of a broader multiorgan vasculitis. Depending on severity, renal vasculitis may present as acute glomerulonephritis (AGN) often associated with hypertension and sometimes with a rapidly deteriorating clinical course. Prompt diagnosis and initiation of therapy are key to preserving kidney function and preventing long-term morbidity and mortality. This review focuses on the clinical presentation, diagnosis, and treatment objectives for common forms of renal vasculitis seen in pediatric patients.

Network Pharmacology and Molecular Docking Analysis to Explore the Mechanism of Huaiqihuang-Mediated Alleviation of Henoch–Schönlein Purpura Nephritis

Objective

Henoch–Schönlein purpura nephritis (HSPN) is considered a major cause of chronic renal failure and is the most common secondary glomerular disease in children. Huaiqihuang (HQH), a traditional Chinese herbal formula, exhibits therapeutic effects against HSPN in clinical practice. However, the potential molecular targets and mechanisms underlying HSPN treatment remain unclear.

Methods

By constructing a protein-protein interaction (PPI) network, core targets related to HQH and HSPN were identified. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathways were analyzed to identify the main pathways related to HSPN based on the core targets. To screen the main active ingredients of HQH against HSPN, an ingredient-target-pathway network was constructed using the top 10 main pathways associated with HSPN. Then, molecular docking was performed to explore the interactions and binding patterns between molecules and proteins.

Results

Clinical data showed that HQH combined with conventional medicine significantly reduced 24-hour urine protein excretion, urine microalbumin levels, and erythrocyte counts in the urine sediment of HSPN patients. By constructing PPI models, 15 potential core targets were identified. The top 10 main pathways showed higher enrichment ratios, including the cytokine–cytokine receptor interaction and signaling pathways related to NOD-like receptor, IL-17, etc. Through the ingredient-target-pathway network and molecular docking, we revealed that five active ingredients of HQH had good affinities with three core targets, AKT1, MMP9, and SERPINE1, which may be vital in treating HSPN.

Conclusions

The study preliminarily explored the active ingredients, targets, and pathways involved in HQH therapy for HSPN. The mechanism of HQH therapy may be attributed to the modulation of inflammatory response, immune response, and oxidative stress. Combined with clinical data, our results indicate that HQH is highly effective in treating HSPN.

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.

Increased CD8+ T cells in patients with Henoch-Schonlein purpura nephritis exhibit suppressive immune activity

BACKGROUND

About 40% to 50% of children with Henoch-Schonlein purpura often suffer from nephritis, which can cause irreversible renal damage. Significantly increased peripheral T lymphocytes and reduced B lymphocytes have been widely reported as hallmarks of Henoch-Schonlein purpura nephritis (HSPN) differing from Henoch-Schonlein purpura without nephritis (HSP). While the role of peripheral immune cells, especially CD8+ T cells, in the development of nephritis of Henoch-Schonlein purpura is not clear.

OBJECTIVES

To explore the changes of peripheral CD8+ T cells and the association of CD8+ T cell markers with indicators of renal function in HSP and HSPN patients.

PATIENTS AND METHODS

A total of 27 HSP and 16 HSPN patients were included in this study. The serum urea, serum creatinine, 24-hour urinary protein and peripheral white blood cell counts were collected from hospital registry systems. The T cell surface markers (CD28, CD107a and CD69) and cytokine (TNFα and IFNγ) secretion capacity were measured by flow cytometry.

RESULTS

Compared with HSP patients, The number of CD8+ T cells in HSPN patients increased significantly (p=0.0003) and demonstrated with decreased CD69 expression (p<0.0001) and decreased cytokine secretion. The expression level of CD69 in CD3+, CD4+ and CD8+ T cells all significantly correlated negatively with serum creatinine and 24-hour urinary protein in HSP and HSPN children.

CONCLUSIONS

The inhibition of CD8+ T cell activity was significantly related to the decline of renal function in HSP and HSPN patients. It is possible to monitor renal function by detecting the expression of CD69 on CD8+ T cells in HSP and HSPN patients.

Time of Onset and Risk Factors of Renal Involvement in Children with Henoch-Schönlein Purpura: Retrospective Study

BACKGROUND

Henoch-Schönlein purpura (HSP) is a common systemic vasculitis in children, involving the skin, musculoskeletal system, gastrointestinal tract and kidneys. Some studies in children have shown possible risk factors linked with the development and severity of HSP Nephritis (HSPN). The aim of this study was to research predicting factors for the development of HSPN.

METHODS

We retrospectively evaluated 132 pediatric patients with HSP, according to EULAR/PRINTO/PRESS criteria. All patients were screened for HSPN by urinalysis. Finally, we compared demographic, clinical and laboratory data in HSP patients with and without nephritis.

RESULTS

The median age at HSP diagnosis [6.2 (2.6-17.5) vs. 5.5 (0.8-15.4) years, p = 0.03] and the incidence of abdominal pain (48 vs. 27%, p = 0.01) were significantly higher in HSPN patients. No differences were evidenced regarding gender, allergic diseases, skin recurrences, gastrointestinal involvement, musculoskeletal involvement, scrotal involvement, and laboratory data (white blood cell count, neutrophil count, lymphocyte count, platelet count, C-reactive protein, erythrocyte sedimentation rate, and blood concentration of IgA).

CONCLUSIONS

The age at diagnosis and abdominal pain were independent risk factors for renal involvement in HSP patients. However, due to the retrospective nature of this study, further long-term and prospective studies will be necessary.

Clinicopathological Spectrum of Henoch-Schönlein Purpura Vasculitis: An Experience from a Tertiary Care Center

Henoch-Schönlein purpura (HSP) is a small vessel vasculitis with multiorgan involvement. Renal involvement is the key factor predicting morbidity. We have aimed to analyze the clinicopathological spectrum of HSP vasculitis and HSP nephritis to assess the risk factors associated with kidney involvement. This retrospective study was performed in the department of pathology with collaboration of department of dermatology and department of nephrology of a tertiary care center. All clinical details along with biopsy findings were retrieved. Starting materials of the study were cases of leukocytoclastic vasculitis with only perivascular IgA deposit of more than ++ in the absence of other immunoglobulin and trace complements. To investigate the possible factors that are influential on the development of biopsy-proven HSP nephritis, we divided the whole study population in two groups -group 1: with and group 2: without biopsy-proven nephritis. One-way analysis of variance was carried out during comparative analysis between two groups using IBM SPSS statistics software, version 19 and MedCalc software, version 12.3.0.0. HSP vasculitis comprised 11.6% (n = 19) of total cutaneous vasculitis in 2 years (164 cases) with a mean age of 13.52 ± 8.10 (range: 4-33 years). Three cases developed de novo kidney disease (15.79%). A correlation analysis revealed that predictors were seasonal variation (P = 0.018), severe gastrointestinal involvement (P = 0.03), and subcutaneous edema (P = 0.005). Various clinical and laboratory parameters were associated with renal consequences. Occult nephritis was the most common presentation with crescent as a constant histopathological feature.

Comparison of clinical, pathological and long-term renal outcomes of children with Henoch-Schonlein purpura nephritis and IgA nephropathy

PURPOSE

To compare clinical, pathological, and long-term renal outcomes of children with Henoch-Schonlein purpura nephritis (HSPN) and IgA nephropathy (IgAN).

METHODS

The medical records of patients diagnosed as HSPN and IgAN during childhood were evaluated retrospectively. HSPN and IgAN groups were compared in terms of gender, age, upper respiratory infection history, blood pressure; presence of nephrotic and/or nephritic syndrome; hemoglobin level, leukocyte count, C-reactive protein (CRP), serum albumin (sAlb), creatinine, complement 3 (sC3), complement 4 (sC4) and immunoglobulin A (sIgA) levels; estimated glomerular filtration rate (eGFR) and proteinuria levels; and renal pathology findings at the onset of disease; total follow-up time; and blood pressure, eGFR and proteinuria levels at the last visit.

RESULTS

Fifty-four patients were enrolled in the study [38 (70%) HSPN and 16 (30%) IgAN]. The median follow-up time was 60.5 and 72.0 months in HSPN and IgAN groups, respectively (p > 0.05). The HSPN and IgAN groups were also not different in terms of gender, age at the onset; leukocyte count, eGFR, sC3-sC4-sIgA levels; and the presence of endocapillary, extracapillary and mesangial proliferation, tubular atrophy, interstitial fibrosis and IgA, IgM, C3 accumulation in renal tissue. Upper respiratory tract infection history was more common in children with IgAN (8/16 vs 8/38, p = 0.045). sAlb (3.96 ± 0.58 vs 4.40 ± 0.46 g/dL, p = 0.005), hemoglobin (12.1 ± 1.3 vs 13.3 ± 1.2 g/dL, p = 0.004,) and the incidence of mesangial IgG deposition (15/38 vs 11/16, p = 0.049) were lower, while CRP (16.3 ± 7.2 vs 7.8 ± 4.4 mg/L, p = 0.002) and proteinuria (72.1 ± 92.4 vs 34.2 ± 37.9 mg/m2/24 h, p = 0.041) was higher in HSPN group at the onset of disease. Proteinuria and eGFR were similar between the two groups at last visit.

CONCLUSION

Children with HSPN and IgAN have little clinical and histological differences in our population. The most prominent difference at presentation with nephritis was higher proteinuria in HSPN probably associated with inflammation due to systemic vasculitis. Long-term renal outcome was good in both HSPN and IgAN.

Efficacy and Safety of Tacrolimus in the Treatment of Pediatric Henoch-Schönlein Purpura Nephritis

BACKGROUND

Children with severe Henoch-Schönlein purpura nephritis (HSPN) may progress to end-stage renal disease without appropriate treatment.

OBJECTIVE

This study aimed to investigate the efficacy and safety of tacrolimus combined with glucocorticoids in the treatment of pediatric HSPN.

METHODS

A total of 87 HSPN patients with urinary protein ≥ 0.75 g/24 h received standard of care, including angiotensin II receptor blockers/angiotensin-converting enzyme inhibitors and glucocorticoids. Patients were divided into three groups and additionally received tacrolimus (n = 30), cyclophosphamide (n = 31), or mycophenolate mofetil (MMF) (n = 26). We monitored outcome measures, including proteinuria, hematuria, and renal function and analyzed the efficacy and side effects in each group.

RESULTS

At 2-month follow-up, the overall efficacy was 93.3%, 83.9%, and 61.5% for tacrolimus, cyclophosphamide, and MMF, respectively (P < 0.05). Urinary protein significantly decreased for all groups. Urinary red blood cell counts significantly decreased for patients treated with tacrolimus (P < 0.001) and cyclophosphamide (P < 0.05), whereas no significant decrease was seen for those receiving MMF (P = 0.09). Although urine β2-microglobulin significantly decreased following 2 months of treatment with all medications, efficacy was greater with tacrolimus than with cyclophosphamide and MMF (P < 0.001). Major adverse events were respiratory and urinary infections, with MMF having the highest infection rate. The cyclophosphamide group also experienced additional adverse events, including arrhythmia, hemorrhagic cystitis, leukocytosis, thrombocytopenia, and hyperglycemia.

CONCLUSIONS

These results indicate that tacrolimus is more effective at reducing proteinuria and hematuria and improving renal function, with relatively milder side effects, in the treatment of pediatric HSPN.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR2200055323, retrospectively registered on January 7, 2022.

Increased circulating innate lymphoid cell (ILC)1 and decreased circulating ILC3 are involved in the pathogenesis of Henoch-Schonlein purpura

Background

Innate lymphoid cell (ILC) dysfunction is involved in numerous immune diseases, but this has not been demonstrated in Henoch-Schonlein purpura (HSP). This study aimed to investigate whether ILC dysfunction or imbalance participate in the pathogenesis of HSP.

Methods

This was a prospective study in patients with HSP who were hospitalized at the Children’s Hospital of Soochow University from June to December 2019. Age- and sex-matched controls were also enrolled. ILC subsets and lymphocyte subpopulations were determined by flow cytometry. The transmission immune turbidimetric method also facilitated the exploration of correlations between ILC subset frequency and lymphocyte subpopulation, as well as serum IgA in HSP patients.

Results

Fifty-one patients with HSP and 22 control patients were included. There were no differences in age and sex between the two groups. Compared with controls, patients with HSP had higher ILCs in relation to lymphocytes (P = 0.036), higher ILCs in relation to PBMCs (P = 0.026), higher ILC1s (P < 0.001), lower ILC3s (P < 0.05), and higher ILC1/ILC3 ratio (P < 0.001). Sixteen patients underwent routine therapy combined with methylprednisolone for 7–10 days; ILC1s were significantly decreased (P < 0.001) and ILC3s were increased (P = 0.033), and ILC1/ILC3 was significantly decreased (P < 0.001). Compared with the controls, the ratios of ILCs/lymphocytes and ILCs/PBMC were higher in patients in the arthritis and mixed groups (all P < 0.05). ILC1 were elevated in the purpura, arthritis, abdominal, and mixed groups (P = 0.027, P = 0.007, P < 0.001, and P < 0.001, respectively). ILC1/ILCs were positively correlated with CD3 + CD8 + T lymphocytes (r = 0.3701, P = 0.0075). The level of IgA did not correlate with ILCs.

Conclusions

Higher circulating ILC1s and lower circulating ILC3s appear to be involved in the pathogenesis of HSP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03262-w.

New-onset kidney biopsy-proven IgA vasculitis after receiving mRNA-1273 COVID-19 vaccine: case report

As mRNA COVID-19 vaccines have become widely available, cases of new-onset glomerular disease after receiving COVID-19 vaccination have been reported. Here, we present a case of kidney biopsy-proven new-onset IgA vasculitis after receiving the mRNA-1273 (Moderna) COVID-19 vaccination. A 47-year-old man with a 10-year medical history of hypertension and hyperuricemia visited our hospital 19 days after receiving an initial mRNA-1273 COVID-19 vaccine injection for purpuric eruption on the legs and dorsal regions of the feet. Although the eruptions spontaneously improved within 5 days, they developed again at 15 days after the second injection. A histopathological examination of skin biopsy specimens was reminiscent of leukocytoclastic vasculitis, though direct immunofluorescence did not indicate IgA deposition within small vessel walls. Urinalysis indicated severe proteinuria (3 +) and occult blood (3 +). Thus, a kidney biopsy was performed and light microscopy revealed mild mesangial expansion, hypercellularity, and endocapillary hypercellularity, with cellular and fibrocellular crescents observed in three and one, respectively, of a total of 15 glomeruli. Immunofluorescence also showed diffuse granular mesangial staining (3 +) for IgA. Histopathological features were consistent with IgA vasculitis. Intravenous methylprednisolone at 1000 mg for 3 days was initiated, followed by oral prednisolone (0.6 mg/kg/day). Over the following 2-week period, serum creatinine level improved from 1.24 to 1.06 mg/dL and proteinuria decreased from 2.98 to 0.36 g/g Cr, though occult blood persisted. Findings in the present case indicate that new-onset IgA vasculitis after receiving mRNA-1273 COVID-19 vaccine can be treated with corticosteroid therapy.

New Insights and Challenges Associated With IgA Vasculitis and IgA Vasculitis With Nephritis-Is It Time to Change the Paradigm of the Most Common Systemic Vasculitis in Childhood?

What are the challenges ahead and how have we responded so far when it comes to the non-granulomatous systemic vasculitis, characterized mainly by deposits of IgA immune complexes in the endothelium of small blood vessels-IgA vasculitis (IgAV)? That is the question to which we tried to answer. We summarized existing knowledge about epidemiology, pathogenesis, genetics, diagnostic tests and therapy in this somewhat neglected entity in pediatric rheumatology. Since etiopathogenesis of IgA vasculitis is complex, with factors other than galactose-deficient IgA₁-containing immune complexes also being important, and may involve numerous interactions between environmental and genetic factors, genomics alone cannot explain the entirety of the risk for the disease. The incidence of IgAV and nephritis varies worldwide and may be a consequence of overlapping genetic and environmental factors. In addition to the role of the HLA class II genes, some studies have pointed to the importance of non-HLA genes, and modern geostatistical research has also indicated a geospatial risk distribution, which may suggest the strong influence of different environmental factors such as climate, pathogen load, and dietary factors. The application of modern geostatistical methods until recently was completely unknown in the study of this disease, but thanks to the latest results it has been shown that they can help us a lot in understanding epidemiology and serve as a guide in generating new hypotheses considering possible environmental risk factors and identification of potential genetic or epigenetic diversity. There is increasing evidence that an integrative approach should be included in the understanding of IgA vasculitis, in terms of the integration of genomics, proteomics, transcriptomics, and epigenetics. This approach could result in the discovery of new pathways important for finding biomarkers that could stratify patients according to the risk of complications, without an invasive kidney biopsy which is still the gold standard to confirm a diagnosis of nephritis, even if biopsy findings interpretation is not uniform in clinical practice. Ultimately, this will allow the development of new therapeutic approaches, especially important in the treatment of nephritis, for which there is still no standardized treatment.

Hypocomplementemic Atypical IgA Vasculitis: A Case Report

IgA vasculitis (IgAV, also known as Henoch-Schönlein purpura or HSP) is a vasculitis of small vessels involving multiple organs, particularly of the joints, gastrointestinal tract, skin, and kidneys. Growing laboratory evidence has shown that complement plays a key role in the pathogenesis of IgAV, although direct evidence of this association in patients is lacking. We report a child with IgAV associated with clinical features of hypertension, nephrotic range proteinuria, acute kidney injury, and low serum C3, with histopathologic findings on renal biopsy of membranoproliferative glomerulonephritis with C3 and IgA co-dominance, and extensive complement derangements. This case report suggests that complement modifies the pathogenesis of IgAV, and further investigation into complement-targeted therapy in cases of refractory IgAV may be beneficial.

Necessity and choice of therapy for Henoch-Schönlein purpura nephritis

BACKGROUND

Henoch-Schönlein purpura nephritis often resolves spontaneously, without treatment, making decisions regarding therapeutic interventions difficult.

METHODS

Fifty-four patients who were diagnosed as having Henoch-Schönlein purpura nephritis between April 2004 and March 2018, and developed hematuria and/or proteinuria, were studied retrospectively. The observation period ended at the disappearance of hematuria or proteinuria, or the last observation date before December 2019 for each patient. Twenty-four of the patients received no treatment (Group A), 19 underwent renin-angiotensin-aldosterone system inhibitors only (B), 4 experienced steroid pulse therapy and combination therapy only (C) and the remaining 7 received steroid pulse therapy and combination therapy following renin-angiotensin-aldosterone system inhibitors (C). Clinical characteristics were examined according to the treatment method. Survival analysis for persistent urinary abnormalities was performed according to treatment modality, with multiple treatment records created per subject, if necessary.

RESULTS

The highest urine protein/creatinine levels were significantly higher in groups B and C than in group A. The lowest estimated glomerular filtration rate was not significantly different among the three groups. In groups A and B, proteinuria resolved in >90% of patients. Survival analysis showed that steroid pulse therapy and combination therapy was not related to the better resolution of hematuria or proteinuria than renin-angiotensin-aldosterone system inhibitors.

CONCLUSIONS

Several patients with Henoch-Schönlein purpura nephritis went into remission either without treatment or with renin-angiotensin-aldosterone system inhibitors alone. The treatment plan for patients with Henoch-Schönlein purpura nephritis needs to be determined carefully.

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.

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

The aim of the study was to investigate the relationship between the severity of typical clinical symptoms, severity of histopathological lesions in kidney biopsies in IgA vasculitis nephritis (IgAVN) and to propose indications for kidney biopsy in children.

MATERIAL AND METHODS

This retrospective study enrolled 106 patients, included in the IgAVN registry of Polish children, diagnosed by kidney biopsy. Renal and extrarenal symptoms at onset of the disease were analyzed. Biopsy results were assessed using Oxford classifications (MEST-C). The patients were divided into 3 groups depending on the severity of proteinuria: A-nephrotic proteinuria with hematuria; B-non-nephrotic proteinuria with hematuria; C-isolated hematuria.

RESULTS

The first symptoms of nephropathy were observed at the 0.7 (1-128.4) months from the onset of extrarenal symptoms. Kidney biopsy was performed on 39 (6-782) days after the onset of nephropathy symptoms. MEST-C score 4 or 5 was significantly more frequent in children from group A than in groups B and C. Significantly higher mean MEST-C score was found in patients with abdominal symptoms than without. In group A: S0 and T0 we found in significantly shorter time to kidney biopsy than in S1, T1-2 p < 0.05) and in group B the significantly shorter time in T0 compare to T1-2 p < 0.05). The ROC analysis shows that S1 changes appear in kidney biopsies in group A with cut off 21 days (AUC 0,702, p = 0.004, sensitivity 0.895 specificity 0.444) T1-2 changes after 35 days (AUC 0.685, p = 0.022, sensitivity 0.750, specificity 0.615), and in goupn B T1-2 cut off is 74 days (AUC 0,738, p = 0.002, sensitivity 0.667, specificity 0.833).

CONCLUSIONS

In childhood IgAVN, the severity of changes in the urine is clearly reflected in the result of a kidney biopsy. The biopsy should be performed in patients with nephrotic proteinuria no later than 3 weeks after the onset of this symptom in order to promptly apply appropriate treatment and prevent disease progression. Accompanying abdominal symptoms predispose to higher MESTC score.

Leflunomide therapy for IgA vasculitis with nephritis in children

BACKGROUND

Henoch-Schönlein purpura (HSP), also called IgA vasculitis, is a systemic vasculitis characterized by deposits of immunoglobulin A in blood vessels. Renal impairment of these patients is the main determinant of prognosis. The optimal treatment of HSP nephritis (HSPN) in children remains controversial, but many clinicians administer an immunosuppressive agent with a corticosteroid. A previous study reported that leflunomide (LEF) with a corticosteroid was effective for adult patients with HSPN and nephrotic proteinuria. However, data on this treatment in pediatric patients is limited.

METHODS

We described our experience at a single center on the use of LEF in 5 pediatric patients who had IgA vasculitis with proteinuria that was nearly 50 mg/kg (nephrotic range) and remained high despite administration of intravenous steroid, and biopsy-proven nephritis. All patients had class II to IIIb lesions based on the International Study of Kidney Disease in Children (ISKDC).

RESULTS

We successfully treated all 5 children who had IgA vasculitis with nephritis using LEF with a corticosteroid. Four patients achieved a complete remission of proteinuria, and 1 patient had significantly reduced proteinuria. The children received LEF for 6 months to 12 months, and none of them had severe adverse events.

CONCLUSIONS

To our knowledge, this is the first case series to report successful treatment of pediatric HSPN with LEF in combination with a corticosteroid.

IgA vasculitis nephritis in children and adults: one or different entities?

The clinical features of the kidney involvement in immunoglobulin A (IgA) vasculitis (IgAVN) differ in children and adults for both clinical presentation and progression. IgAVN in children has mostly a self-limiting course and favorable resolution, while in adults the kidney involvement is frequently severe with unfavorable outcome. However, a subset of children is at risk of progression within the pediatric age or decades later in adulthood, particularly when the diagnosis and a prompt intervention are delayed. Factors predicting progression and outcome in the whole spectrum of age have been investigated in recent research, as well as the relationship between IgAVN and primary IgAN, which share the same pathology features, in the light of peculiar clinical differences and progression tendencies, and hence need for selective treatments. The search for a personalized treatment in children with IgAV and in different ages of life should rely on the identification of different risks for progression. This review will focus on recent studies which contribute to improve our knowledge in this still largely unclear area.

Renal biopsy in children with IgA vasculitis

Introduction

Henoch-Schönlein purpura nephritis (HSN) is defined as Henoch-Schönlein purpura with kidney involvement, including hematuria and/or proteinuria. The aim of this study was to evaluate the data of HSN patients who underwent renal biopsy, and compare the main clinical and laboratory parameters that may affect renal biopsy findings, treatment protocols, and short- and long-term outcome of those patients.

Methods

Biopsies performed in 72 HSN patients between January 2007 to January 2017 were retrospectively evaluated. They were divided into two groups according to renal biopsy classification of the International Study of Kidney Disease in Children. Renal outcome, clinical and laboratory parameters, treatment protocols, and outcome were compared between groups. Short- and long-term follow-up of patients were evaluated.

Results

Of 72 patients, 47 were male (65.3%) and 44 (61.1%) were ≤10 years of age. Neutrophil-lymphocyte ratio was found higher in patients with scrotal involvement (p=0.042). Short-term unfavorable outcome was significantly higher in patients with scrotal involvement (p=0.038). Patients with hypertension and decreased creatinine clearance were found to have more unfavorable outcomes in long-term follow-up (p=0.029, p=0.040).

Conclusion

Cyclosporin-A and cyclophosphamide could be effective in steroid unresponsive HSN patients. Patients with scrotal involvement, decreased creatinine clearance, and hypertension should be closely monitored for sequelae of HSN.

IgA Vasculitis in Adults: a Rare yet Challenging Disease

PURPOSE OF REVIEW

IgA vasculitis (IgAV) is a rare and poorly understood systemic vasculitis in adults. Its diagnosis and treatment remain a challenge. Herein, we review the clinical manifestations, diagnosis, management, and prognosis of IgAV in adults.

RECENT FINDINGS

The clinical course of IgAV in adults appears to be different from pediatric IgAV, especially due to its higher risk of evolving into end-stage renal disease. Rising awareness and interest in adult-onset IgA vasculitis has resulted in recent increasing number of publications on different treatment experiences. However, there is still controversy over the role of glucocorticoid (GC) and different immunosuppressive therapies such as cyclophosphamide, rituximab, and mychophenolate mofetil for more severe IgAV. Data regarding potential benefits of targeting the mucosal immune system, toll-like receptors, complements, and tyrosine kinase inhibitors in the treatment of IgA nephropathy are emerging. High quality evidence or guidelines in the treatment of severe IgAV are lacking and there is still a great need for controlled trials.

Efficacy and safety of low-dose corticosteroid with azathioprine in the treatment of elderly-onset IgA vasculitis with nephritis

The diagnosis of elderly-onset IgA vasculitis (IgAV) and its prognosis can be difficult to ascertain because of its rarity and the frequent presence of comorbidities. Furthermore, the treatment of elderly-onset IgAV remains controversial. We report a case of IgAV in an 87-year-old patient. Renal involvement was detected early during the IgAV follow-up. He was treated with low-dose corticosteroid and azathioprine, which led to a complete remission without any adverse effects. This suggests that precise intervention with early diagnosis and careful renal follow-up may prevent renal failure and that low-dose steroids with azathioprine can be an effective treatment for elderly-onset IgAV with nephritis.

Predictability of the Oxford classification of IgA nephropathy in Henoch-Schonlein purpura nephritis

BACKGROUND

Whether the Oxford classification of immunoglobulin A nephropathy can be utilized to predict the adverse renal outcome of Henoch-Schonlein purpura nephritis (HSPN) has been long-debated. We, therefore, performed a meta-analysis to evaluate the prognostic value of Oxford classification lesions in HSPN.

METHODS

We systematically searched Medline, EMBASE, Web of Science, and the Cochrane Library for articles published from January 1970 to August 2020. Cohort and case-control studies investigating the correlation between the Oxford classification and renal outcome were included, the quality of which was assessed by the Newcastle-Ottawa scale criteria. The pooled odds ratios (ORs) with their 95% confidence intervals (CIs) were calculated with a random-effects model or a fixed-effects model depending on the heterogeneity.

RESULTS

A total of 485 papers were reviewed and eventually 9 comparisons were included, providing data of 1688 patients with HSPN. ORs for adverse renal events were 2.83 (95% CI 1.84-4.35; P < 0.001), 1.96 (95% CI 1.28-2.98; P < 0.05), and 5.45 (95% CI, 3.15-9.45; P < 0.001) for patients with lesions of endocapillary hypercellularity (E), segmental sclerosis (S), and tubular atrophy /interstitial fibrosis (T), respectively, without significant heterogeneity (E: I² = 0.0%; P = 0.498; S: I² = 22.4%; P = 0.258; T: I² = 33.6%; P = 0.171). Subgroup analysis adjusted for age also supported the results that E, S, and T lesions could serve as poor predictors (P < 0.05). Additionally, crescents (C) were strongly associated with renal outcome (OR 2.22; 95% CI 1.62-3.04; P < 0.001), with moderate heterogeneity (I² = 49.3%; P = 0.066). However, it should be noted that it is not the presence but the proportions of crescent lesions that were related to the high risk of progression to adverse renal events, because the predictability of lower rates of crescent (C1, with crescents > 0 and ≤ 25%) was uncertain (OR 2.21; 95% CI 0.75-6.51; P > 0.05). Although the pooled OR revealed that lesions of mesangial hypercellularity (M) were correlated with poor renal prognosis (OR 2.41; 95% CI 1.07-5.43; P < 0.05), subgroup analysis separating children from adults indicated that there seemed to be no significant difference.

CONCLUSIONS

Oxford classification, especially for E, S, T, and C, might be recommended for patients with HSPN, regardless of children and adults.

Clinical effect of combined western medicine and traditional Chinese medicine on children with Henoch-Schönlein purpura nephritis

OBJECTIVE

To investigate the efficacy of combined Chinese and western medicine in the treatment of children with Henoch-Schönlein purpura nephritis (HSPN) and its effects on immune function, interleukin (IL)-16, and IL-18 expressione.

METHODS

The clinical data of 91 children with HSPN were retrospectively collected and divided into two groups according to the treatment regimen. Group A (n=45) was treated only with western medicine, while group B (n=46) was treated with combined Chinese and western medicine. The clinical efficacy, traditional Chinese medicine (TCM) syndrome points before and after treatment, immune function indices, urinary indices, levels of IL-16 and IL-18, and the recurrence rate were compared between the two groups.

RESULTS

The total effective rate was 95.65% in group B, higher than 75.56% in group A (P<0.05). The TCM scores after treatment in group B was lower than that in group A (P<0.05). The levels of immunoglobulin IgA and IgM after treatment were lower while IgG levels were higher in group B than those in group A (P<0.05); Urinary microalbumin, urinary beta₂ microglobulin, 24 h urine protein elimination, and red blood cells (RBC) in the urine were lower in group B after treatment than in group A (P<0.05). The serum levels of IL-16 and IL-18 in group B were lower than those in group A after treatment (P<0.05). The recurrence rate was 4.35% in group B, lower than 26.67% in group A (P<0.05).

CONCLUSION

Combined regimen of western and Chinese medicine in children showed significant efficacy on improving immune function and reducing recurrence rate and IL-16 and IL-18 levels in patients with HSPN.

iTRAQ quantitative proteomic analysis differentially expressed proteins and signal pathways in henoch-schönlein purpura nephritis

Henoch-Schönlein purpura nephritis (HSPN) has been considered as a major cause of chronic renal failure in children and a condition which can worsen clinical outcomes in adults. At present, the molecular mechanisms of HSPN are still unclear. In this study, iTRAQ quantitative proteomic analysis was performed on renal tissues collected from patients with HSPN and compared with those of patients after nephrectomy (controls). A total of 149 differentially expressed proteins (DEPs) were detected, of which, 97 being upregulated and 52 down-regulated. Protein functions and classifications were analyzed using Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). In addition, protein domains. expressive hierarchical clustering analysis and protein-protein interaction (PPI) analysis were also conducted for DEPs. The results of bioinformatics analysis indicated that DEPs were enriched in lipid metabolism and the adherens junction pathway. Among these proteins, CDC42 and CTNNB1 were identified as potential candidates involved in the pathogenesis of HSPN. Immunohistochemistry and real-time PCR further demonstrated that CDC42 and CTNNB1 were up-regulated in HSPN patients. These results provide new and important insights into some underlying molecular pathogenesis of HSPN.

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.

Evaluation of the Oxford classification in immunoglobulin A vasculitis with nephritis: a cohort study and meta-analysis

Background

Similarities in clinicopathological presentations in immunoglobulin A (IgA) nephropathy and IgA vasculitis with nephritis (IgAVN) raise the question of the utility of the Oxford classification in the latter. The aim of this study was to evaluate the Oxford classification in IgAVN.

Methods

We conducted a retrospective cohort study and meta-analysis following systematic searching of the MEDLINE and Excerpta Medica Database (EMBASE) databases between January 2009 and September 2019. We modeled the association of 30 and 50% decline in estimated glomerular filtration rate or end-stage renal disease with pathologic lesions of the Oxford classification including mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), interstitial fibrosis/tubular atrophy (T) and crescents (C). Results were pooled using random-effects meta-analysis.

Results

The cohort study included 132 patients, and only T lesion was an independently risk factor in IgAVN. The meta-analysis yielded six retrospective studies with 721 patients and 139 endpoints. In multivariate model, T lesion was significantly associated with renal outcome (hazard ratio = 2.45, P = 0.007). M and C lesions could not predict renal outcome without evidence of heterogeneity. E and S lesions could not predict renal outcome with evidence of heterogeneity (I ² = 66.6%; P = 0.01, and I ² = 65.8%; P = 0.03, respectively). Subgroup analysis showed that the possible reasons to the heterogeneity were from usage of immunosuppressant, sample size and follow-up time.

Conclusions

The study suggests that the Oxford classification could not be fully validated in IgAVN. Higher portion of immunosuppressant especially before renal biopsy might be the main confounder for the predictive value of Oxford classification in IgAVN.

Initial manifestations and short term follow-up results of Henoch-Schönlein purpura in children: A report from two centers

OBJECTIVE:

This retrospective observational study aims to demonstrate initial signs and symptoms of Henoch-Schönlein purpura (HSP), search for risk factors for gastrointestinal and renal involvement and give short term follow-up results.

METHODS:

The files of newly diagnosed HSP patients from two pediatric rheumatology centers in the southeastern part of the country were retrospectively analyzed in this study. Demographic, clinical features and laboratory results were recorded from the files.

RESULTS:

The cohort consisted of 323 children (males: 53.6%, females: 46.4%). Median age at the time of diagnosis was 7.5 (1.8–17.3) years and the median duration of follow-up was six (3–22) months. The rash was present in all cases but was not the first symptom in 22.9% of the cases. Arthritis and abdominal pain before the development of rash were the initial symptoms in 11.8% and 11.1% of the cases, respectively. Other manifestations were subcutaneous edema (63.2%), arthralgia (57.6%), arthritis (27.6%), myalgia (17.6%), lethargy (10.2%), orchitis (7.5%) and fever (5.3%). Gastrointestinal involvement was seen in 53.3% and renal involvement in 23.5% of the cases. None of the patients developed renal impairment during the follow-up. Older age at diagnosis, necrotic rash, subcutaneous edema, abdominal pain, lethargy, myalgia, arthralgia and arthritis were significantly higher in patients with renal involvement, but none of the demographic, clinical and laboratory features was an independent risk factor for renal or gastrointestinal involvement.

CONCLUSION:

Abdominal pain, arthritis may be the first manifestation of HSP. Having constitutional symptoms, such as fever, myalgia and lethargy at the time of diagnosis, may be warning signs of a more aggressive course with gastrointestinal and renal involvement.

Clinical and Pathophysiological Insights Into Immunological Mediated Glomerular Diseases in Childhood

The kidney is often the target of immune system dysregulation in the context of primary or systemic disease. In particular, the glomerulus represents the anatomical entity most frequently involved, generally as the expression of inflammatory cell invasion or circulant or in situ immune-complex deposition. Glomerulonephritis is the most common clinical and pathological manifestation of this involvement. There are no universally accepted classifications for glomerulonephritis. However, recent advances in our understanding of the pathophysiological mechanisms suggest the assessment of immunological features, biomarkers, and genetic analysis. At the same time, more accurate and targeted therapies have been developed. Data on pediatric glomerulonephritis are scarce and often derived from adult studies. In this review, we update the current understanding of the etiologic events and genetic factors involved in the pathogenesis of pediatric immunologically mediated primitive forms of glomerulonephritis, together with the clinical spectrum and prognosis. Possible new therapeutic targets are also briefly discussed.

A Case of Adult-onset Henoch-Schönlein Purpura Triggered by Fire Ants

Adult-onset IgA vasculitis, also known as Henoch-Schönlein purpura (HSP), is a rare disease that often presents with a non-blanchable, purpuric rash and can simultaneously affect the gastrointestinal, renal and musculoskeletal systems. The etiology of HSP is unknown. It can be triggered by any entity that creates an immunological insult, including medications, infections and vaccines. We describe a unique case of an adult woman who presented with HSP after experiencing multiple insect bites from fire ants and mosquitos while traveling overseas.

MEST-C pathological score and long-term outcomes of child and adult patients with Henoch-Schönlein purpura nephritis

BACKGROUND

Henoch-Schönlein purpura nephritis (HSPN), a small-vessel vasculitis, shares renal pathological features with immunoglobulin A nephropathy. Oxford classification of immunoglobulin A nephropathy pathology has been updated to the MEST-C score, but its application in HSPN remains unresolved.

METHODS

Two hundred and thirteen patients with biopsy-proven HSPN were retrieved from the Seoul National University Hospital between 2000 and 2017. Renal outcome risks (i.e., end-stage renal disease or doubling of serum creatinine) were evaluated according to MEST-C scores after stratification by age: 113 children aged < 18 years (9.2 ± 3.6 years) and 100 adults aged ≥18 years (38.6 ± 18.3 years). We pooled our data with four previous cohort studies in which MEST or MEST-C scores were described in detail.

RESULTS

Twenty-one child (19%) and 16 adult (16%) patients reached the renal outcome during the median follow-up periods of 12 years and 13 years, respectively (maximum 19 years). In children, M1 and T1/T2 scores revealed worse renal outcomes than did M0 and T0 scores, respectively, whereas the T score was the only factor related to worse outcomes in adult patients after adjusting for multiple clinical and laboratory variables. The pooled data showed that M1, S1, and T1/T2 in children and E1 and T1/T2 in adults were correlated with poorer renal outcomes than those of their counterpart scores.

CONCLUSIONS

The Oxford classification MEST-C scores can predict long-term renal outcomes in patients with HSPN.

Prediction of renal outcome in Henoch-Schönlein nephritis based on biopsy findings

BACKGROUND

In Henoch-Schönlein nephritis (HSN), a risk factor for unfavorable outcome is prolonged proteinuria, but the value of renal biopsies in prognosis assessment is debatable.

METHODS

We evaluated serial renal biopsies from 26 HSN patients. Follow-up biopsy occurred at median 2.1 years after diagnostic biopsy. Patients formed two groups at the follow-up biopsy: patients without proteinuria (group I; n = 11) and with proteinuria (group II; n = 15). Biopsies underwent evaluation according to three classifications: International Study of Kidney Disease in Children (ISKDC), Oxford (MEST-C), and semiquantitative classification (SQC) including an activity and chronicity score. Analysis also included expression of pro-fibrotic (alpha-smooth muscle actin and vimentin) and inflammatory (P-selectin glycoprotein ligand-1) molecules in the diagnostic biopsy specimens. Definition of unfavorable outcome was active renal disease or reduced renal function at last follow-up.

RESULTS

Between the biopsies, SQC chronicity score increased in 22 (85%) patients, whereas activity score and ISKDC grade decreased in 21 (81%) and 17 (65%), respectively. Of the MEST-C parameters, endocapillary proliferation (from 83 to 13%; p < 0.001) and crescents (from 63 to 25%; p = 0.022) showed significant reduction, and segmental glomerulosclerosis (from 38 to 79%; p = 0.006) significant increment. These changes occurred similarly in groups I and II. Expression of the pro-fibrotic and inflammatory molecules showed no clinically significant differences between groups I and II. None in group I and five (33%) patients in group II had unfavorable outcome (p = 0.053).

CONCLUSIONS

Our results suggest that follow-up biopsies provide limited additional information to clinical symptoms in HSN outcome prediction.