The ISKDC classification and a new semiquantitative classification for predicting outcomes of Henoch-Schönlein purpura nephritis

Biomarkers to predict kidney outcomes in children with IgA vasculitis

Immunoglobulin A (IgA) vasculitis (IgAV, also known as Henoch-Schoenlein purpura, HSP) is a small vessel vasculitis, most commonly presenting in childhood. In most, it has a straightforward, self-limiting disease course, however some children may develop kidney involvement (IgAV-N) which occurs 4-12 weeks following disease onset and remains the biggest contributor to long-term morbidity. Therefore, children undergo a six-month period of kidney monitoring to identify nephritis via surrogate markers including urinalysis and blood pressure measurements. On-going efforts aim at earlier identification and prevention of nephritis during the window of opportunity between disease onset and established nephritis. By identifying those at highest risk of developing poorer kidney outcomes, the number of children developing chronic kidney disease stage 5 (CKD5) as a result of IgAV-N may be reduced. This review summarizes the latest scientific evidence that support the use of novel biomarkers which may allow nephritis to be identified earlier compared to traditional markers, as well as the risk stratification of children with established IgAV-N. These biomarkers may also enhance the evolving understanding of underlying inflammatory pathways. Promising novel urinary markers of early nephritis include angiotensinogen, Gd-IgA1, various complement proteins, and MCP-1, and serum markers such as α-SMA, C-Met, PTX-3, MMP-9, MRP 8/14, and adiponectin may help identify those at risk of developing CKD5. Prospective, longitudinal, international validation studies are required to investigate these markers further, including exploration of implementation into clinical practice.

Assessment of renal resistive index measurement in children with immunoglobulin A vasculitis

Introduction

Henoch-Schönlein purpura (HSP), also known as IgA vasculitis (IgAV), is the most prevalent systemic vasculitis. Renal involvement occurs in approximately one third of children with IgAV, while biopsy-proven nephritis could be diagnosed in only 6% of patients with prolonged proteinuria or nephritic syndrome. The renal resistive index (RRI) provides insights into intrarenal arterial resistance. The aim of this study was to assess the potential utility of RRI measurements in patients with IgA vasculitis (IgAV).

Material and methods

This cross-sectional study included 27 children diagnosed with HSP/IgAV between January 2021 and January 2023. Additionally, 27 healthy controls were included to the study. Age, sex, symptoms recorded and initial laboratory test results, including renal function tests, serum albumin levels, complete blood count, erythrocyte sedimentation rate, C-reactive protein, renal function tests, spot urine protein/creatinine and albumin/creatinine ratio were obtained at study enrollment. The RRI measurements were obtained from intrarenal arteries using color Doppler ultrasonography.

Results

Among the 27 IgAV patients (13 male, 14 female), 3 (11.1%) exhibited renal involvement, with renal biopsy performed in only one patient, revealing class IIIa nephritis. The RRI values were not significantly different between the IgAV and control groups. Additionally, RRI was 0.61 ±0.05 and 0.56 ±0.06 in patients with and without antecedent infection, respectively (p = 0.04). Furthermore, RRI was not significantly different among patients grouped based on the presence of arthritis, severe gastrointestinal symptoms, or renal involvement.

Conclusions

Our findings indicate that RRI remains unaffected in patients with IgAV, reflecting the relatively benign nature of the disease, particularly in children. Further investigations, involving a larger cohort of patients with nephritis, are warranted to elucidate the utility of RRI in assessing renal involvement in IgAV.

IPNA clinical practice recommendations for the diagnosis and management of children with IgA nephropathy and IgA vasculitis nephritis

IgA nephropathy and IgA vasculitis with nephritis, albeit rare, represent two relatively frequent glomerular conditions in childhood. Compared to adults, pediatric IgA nephropathy has a more acute presentation, most frequently with synpharyngitic macrohematuria and histologically with more intense inflammation and less intense chronic damage. Management of these conditions is controversial and supported by little high-quality evidence. The paucity of evidence is due to the disease heterogeneity, its inter-ethnic variability, and the difficulty of extrapolating data from adult studies due to the peculiarities of the condition in children. IgA vasculitis with nephritis is a kidney manifestation of a systemic disorder, typical of the pediatric age, in which both the diagnosis of kidney involvement and its management are poorly defined, and an interdisciplinary approach is crucial. Both conditions can have a profound and long-lasting impact on kidney function and the global health of affected children. The International Pediatric Nephrology Association has therefore convened a diverse international group of experts from different disciplines to provide guidance on the recommended management of these conditions in children and to establish common definitions and define priorities for future high-quality, evidence-based collaborative studies for the benefit of children.

National recommendations for the management of children and young people with IgA vasculitis: a best available evidence, group agreement-based approach

OBJECTIVE

IgA vasculitis (IgAV) is the most frequently experienced subtype of vasculitis seen in children. Most children fully recover, however, complications including chronic kidney disease are recognised. The aim of this project was to use a best available evidence, group agreement, based approach to develop national recommendations for the initial management of IgAV and its associated complications.

METHODS

A fully representative multiprofessional guideline development group (GDG), consisting of 28 members, was formed and met monthly. Graded recommendations were generated using nationally accredited methods, which included a predefined scope, open consultation, systematic literature review, evidence appraisal, review of national or international guidelines and a period of open consultation. Audit measures and research priorities were incorporated.

RESULTS

The IgAV GDG met over a 14-month period. A total of 82 papers were relevant for evidence synthesis. For the initial management, four topic areas were identified with five key questions generating six graded recommendations related to classification, specialist referral and musculoskeletal involvement. For the associated complications, five topic areas with 12 key questions generated 15 graded recommendations covering nephritis, gastrointestinal and testicular involvement, atypical disease and follow-up. Open consultation feedback was incorporated. The guidelines were endorsed by the UK Kidney Association and Royal College of Paediatrics and Child Health and are available online.

CONCLUSION

Despite IgAV being a rare disease with limited evidence, a national standardised approach to the clinical management for children and young people has been achieved. This should unite approaches to care and act as a foundation for improvement.

Alteration of gut microbiota in Henoch-Schönlein purpura children with gastrointestinal involvement

BACKGROUND

The compositional and structural changes of gut microbiota were closely related to the status of Henoch-Schönlein purpura (HSP).

AIMS

To investigate if clinical indicators and gut microbiota differ between HSP patients with or without gastrointestinal (GI) involvement and to explore the alterations of fecal microbiota in HSP children with and without GI symptoms.

METHODS

A total of 22 children with HSP were enrolled in the study. Fecal microbiota composition was analyzed by 16S rRNA sequencing. Clinical indicators, fecal microbial diversity, and compositions were compared between the two groups.

RESULTS

Respectively, 9 patients with GI involvement (HSP-A) and 13 patients without GI involvement (HSP-N) were enrolled. Prealbumin (PA) and the ratio of immunoglobulin A (IgA) / complement (C)3 were significantly decreased in the HSP-A group and an elevated D-dimer was found in the HSP-N group. The relative abundances of Blautia, Lachnospira, and Haemophilus were significantly higher in the HSP-A group compared to HSP-N. Lower levels of unidentified Prevotellaceae, Parabacteroides, and Romboutsia were found in HSP-A patients. The linear discriminant analysis effect size (LEfSe) showed that the biomarkers for the HSP-A group included Blautia, Anaerostipes, Veillonella, Lachnospira, and Haemophilus. For the HSP-N group, unidentified Prevotellaceae, Intestinibacter, Romboutsia, and Akkermansia were the prominent biomarkers at the genus level. Additionally, the ratio of IgA/C3 exhibited a negative correlation with the genus Blautia. Meanwhile, PA showed negatively correlation with Veillonella.

CONCLUSIONS

These results provide a broader understanding for future microbial-based therapies to decrease the development of GI involvement and improve the clinical outcome of HSP in children.

Outcome of immunosuppression in children with IgA vasculitis-related nephritis

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

IgA vasculitis nephritis: insights from kidney biopsies

PURPOSE OF REVIEW

To present findings indicating the value of kidney biopsy in assessing prognosis and guiding clinical approach to patients with IgA vasculitis nephritis (IgAVN), including a recent international study examining the value of the Oxford (MEST-C) classification.

RECENT FINDINGS

Historically, kidney biopsies with IgAVN are scored using the International Society for Kidney Diseases in Children (ISKDC) classification. However, this classification has limited prognostic value, and most biopsies fall into just two of the six ISKDC grades. There are few studies examining the clinical value of the Oxford classification, which is well documented to be predictive of kidney outcomes in IgA nephropathy, in IgAVN. However, a recent study of 361 biopsied patients with IgAVN showed that endocapillary hypercellularity (Oxford E1) predicted a subclass of patients showing initial improvement in kidney function with immunosuppressive treatment, followed by a later decline.

SUMMARY

Kidney outcome in patients with biopsied IgAVN treated with immunosuppression is determined by clinical factors and endocapillary hypercellularity. The latter is not part of the ISKDC classification and supports including MEST-C scores in biopsy reports of IgAVN. Even patients showing a good initial response to immunosuppression require long-term follow-up due to risk of subsequent kidney function decline.

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.

Histologic and Clinical Factors Associated with Kidney Outcomes in IgA Vasculitis Nephritis

BACKGROUND

Nephritis is a common manifestation of IgA vasculitis and is morphologically indistinguishable from IgA nephropathy. While MEST-C scores are predictive of kidney outcomes in IgA nephropathy, their value in IgA vasculitis nephritis has not been investigated in large multiethnic cohorts.

METHODS

Biopsies from 262 children and 99 adults with IgA vasculitis nephritis ( N =361) from 23 centers in North America, Europe, and Asia were independently scored by three pathologists. MEST-C scores were assessed for correlation with eGFR/proteinuria at biopsy. Because most patients ( N =309, 86%) received immunosuppression, risk factors for outcomes were evaluated in this group using latent class mixed models to identify classes of eGFR trajectories over a median follow-up of 2.7 years (interquartile range, 1.2-5.1). Clinical and histologic parameters associated with each class were determined using logistic regression.

RESULTS

M, E, T, and C scores were correlated with either eGFR or proteinuria at biopsy. Two classes were identified by latent class mixed model, one with initial improvement in eGFR followed by a late decline (class 1, N =91) and another with stable eGFR (class 2, N =218). Class 1 was associated with a higher risk of an established kidney outcome (time to ≥30% decline in eGFR or kidney failure; hazard ratio, 5.84; 95% confidence interval, 2.37 to 14.4). Among MEST-C scores, only E1 was associated with class 1 by multivariable analysis. Other factors associated with class 1 were age 18 years and younger, male sex, lower eGFR at biopsy, and extrarenal noncutaneous disease. Fibrous crescents without active changes were associated with class 2.

CONCLUSIONS

Kidney outcome in patients with biopsied IgA vasculitis nephritis treated with immunosuppression was determined by clinical risk factors and endocapillary hypercellularity (E1) and fibrous crescents, which are features that are not part of the International Study of Diseases of Children classification.

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.

Comparative study on clinicopathological features and prognosis of IgA vasculitis nephritis and IgA nephropathy in children

BACKGROUND

IgA vasculitis nephritis (IgAVN) and IgA nephropathy (IgAN) share several clinical and pathological characteristics, though distinctions also exist. Their interrelation, however, remains undefined. This study investigates the clinicopathological divergences and prognostic disparities in pediatric patients with IgAVN and IgAN.

METHODS

Our study encompasses 809 pediatric patients with IgAVN and 236 with IgAN, all of whom underwent kidney biopsy. We utilized the Semiquantitative Classification (SQC) scoring system to juxtapose the pathologies of the two conditions, and performed a COX regression analysis to examine factors influencing their prognoses.

RESULTS

Both patient groups demonstrated a predominance of males. A seasonality was observed, with a higher incidence of IgAN in the summer, and IgAVN in the fall (P < 0.0001). Patients with IgAN exhibited more severe tubulointerstitial injury, higher chronicity index, and total biopsy scores compared to those with IgAVN (P < 0.0001). Mesangial deposition intensity of complement C3, and the rate of pure IgA deposition, were found to be greater in patients with IgAVN compared to those with IgAN (P < 0.0001). The intensity of IgA deposition was also significantly higher in IgAVN patients (P = 0.003). IgAVN demonstrated a superior prognosis, with a higher rate of kidney remission (P < 0.0001). COX regression analysis indicated that interstitial fibrosis, as identified in the SQC pathology system, was associated with the prognosis of both conditions. Furthermore, the findings suggest that IgA deposition levels (IgA +  + and IgA +  + +) could potentially influence the prognosis of IgAVN.

CONCLUSIONS

Compared to IgAVN, IgAN manifests more severely with regard to renal impairment, interstitial damage, and prognosis. The disparities in immune complex deposition levels and locations within the kidneys support the hypothesis of IgAVN and IgAN as distinct diseases. Interstitial fibrosis may serve as a key pathological indicator within the SQC system associated with kidney prognosis in children with IgAVN and IgAN. The degree of IgA deposition could also be linked with the prognosis 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.

Adding Methylprednisolone and Cyclophosphamide Pulse Therapy Provides No Benefit in Pediatric IgAV Nephritis Grade III

Although immunoglobulin (Ig) A vasculitis (IgAV) nephritis is a common form of secondary pediatric glomerulonephritis, there is no consensus on an appropriate therapeutic regimen for moderate-to-severe pediatric IgAV nephritis grade III or the effectiveness of aggressive immunosuppressive therapy. The objective is to evaluate the efficacy and renal outcomes of methylprednisolone pulse therapy with or without cyclophosphamide pulse therapy for grade III IgAV nephritis in children. This retrospective, single-center study included 115 children with IgAV nephritis grade III. The primary endpoint was proteinuria reduction from moderate or severe levels to a normal level. The secondary endpoint was stable renal function, that is, an increase of less than 25% from the baseline creatinine level over the 4-month follow-up period. Among 115 children with IgAV nephritis grade III, 59 received methylprednisolone and cyclophosphamide double-pulse treatment; methylprednisolone and cyclophosphamide double-pulses did not significantly improve proteinuria remission. Proteinuria improvement did not show any difference with or without cyclophosphamide treatment. Furthermore, methylprednisolone pulse therapy showed no benefit over steroid therapy alone. The demographic and baseline disease characteristics among the treatment groups were well-balanced. The rates of complete remission in 24-hour proteinuria excretion over the 4-month follow-up period in the methylprednisolone and cyclophosphamide double-pulse, methylprednisolone plus oral prednisolone, and oral prednisolone-only groups were 91.52%, 92.31%, and 100%, respectively. Renal function remained stable in all the patients. Most patients with IgAV nephritis grade III showed a good prognosis. However, the addition of methylprednisolone and/or cyclophosphamide pulses did not offer benefits over steroid-only therapy.

Renal histopathological manifestations of IgA vasculitis nephritis in children and adults

BACKGROUND

IgA vasculitis nephritis (IgAVN) is a common form of secondary glomerulonephritis and can occur in patients of any age. Our study was designed to reveal renal histopathological manifestations of children and adults with IgAVN and to explore the potential pathogenesis of IgAVN.

METHODS

Sixty-one pediatric and seventy adult patients with IgAVN were enrolled altogether, and all of them underwent kidney biopsies. General information, laboratory parameters, and renal histopathological manifestations of all patients were analyzed.

RESULTS

(1) Diabetes, hypertension, and various levels of proteinuria made no difference between children and adults. (2) Global sclerosis and tubular atrophy/interstitial fibrosis occurred more commonly in adults than in children (24.29 % vs 8.20 %, 65.71 % vs 9.84 %, respectively) (P < 0.05). (3) The immunofluorescence deposition of complement C3 was more apparent in adults (P < 0.05). (4) The deposition of IgA, IgG, IgM, and C3 in kidneys was unrelated to the pathological types. (5) The deposition of IgG or IgM was related to the deposition of IgA or C3 in children and adults (P < 0.05).

CONCLUSIONS

Chronic kidney injury occurred more commonly in adult IgAVN patients compared to pediatric IgAVN patients. Immunoglobulin and complement deposits in kidneys were independent of the types of renal pathological injury. Additionally, IgG and IgM were probably involved in IgAVN pathogenesis.

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.

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.

Hemoperfusion and intravenous immunoglobulins for refractory gastrointestinal involvement in pediatric Henoch-Schönlein purpura: a single-center retrospective cohort study

BACKGROUND

Henoch-Schönlein purpura (HSP) with refractory gastrointestinal (GI) symptoms is always difficult to handle because of its resistance to supportive therapies and glucocorticoid. This study aimed to evaluate the efficacy of hemoperfusion (HP) and intravenous immunoglobulins (IVIG) therapies in this population.

METHODS

Sixty-four HSP patients with refractory GI involvement (R-GI group) and 64 cases with mild GI symptoms (control group) were retrospectively analyzed in our center from March 2016 to October 2019. In R-GI group, 42 cases (subgroup A) were treated with IVIG and steroid, 13 cases (subgroup B) used HP and steroid, 9 cases (subgroup C) executed a combination of IVIG, HP and steroid. Demographic characteristics, clinical features, laboratory indexes and treatment outcomes were recorded. t-test, One-way ANOVA, Mann-Whitney U test, and multivariate logistic regression were used in comparing differences among subgroups and predicting independent risk factors.

RESULTS

Compared with the control group, R-GI cases experienced higher risk of renal involvement (P = 0.000), more steroid exposure (P = 0.000), six times expenses (P = 0.000) and 2.3 times length of hospitalization (P = 0.000). The independent risk factors of R-GI group were elevated neutrophils (OR 1.250 [95% CI 1.130-1.383]) and the percentage of B lymphocytes (OR 1.100 [95% CI 1.026-1.179]) as well as decreased IgG (OR 0.847 [95% CI 0.732-0.98]). In R-GI group, increased age (OR 1.039 [95% CI 1.016-1.062]) and IgM (OR 5.994 [95% CI 1.403-27.611]) were verified to be risk factors of HSP nephritis. All three subgroups could alleviate the symptoms effectively. Compared with those in subgroup A, patients in subgroup B were elder (P = 0.004), had less relapse (P = 0.002), steroid exposure (P = 0.033) and expenses (P = 0.031), more significant decrease of WBC (P = 0.026) after treatment.

CONCLUSION

The HSP with refractory GI involvement had much higher risk of medical burden and renal involvement. Both IVIG and HP therapies could ameliorate refractory GI symptoms efficiently. HP therapy tended to reduce the relapse, costs and steroid exposure in its audiences who were cooperated and with stable hemodynamics, while IVIG had better use in younger children.

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.

Half of children with IgA vasculitis-associated nephritis with nephrotic state spontaneously recover

BACKGROUND

The clinical spectrum of Henoch-Schönlein purpura nephritis (HSPN), now known as IgA vasculitis-associated nephritis (IgAVN), ranges from isolated microscopic haematuria to nephrotic syndrome, progressive glomerulonephritis, and kidney failure. The outcome also varies, and the management of IgAVN is controversial. The presence of nephrotic state at disease onset is thought to be a risk factor of a poor prognosis. However, not all patients with nephrotic state have a poor prognosis, and it is unclear whether they need early treatment.

METHODS

We herein retrospectively examined the clinical course of paediatric IgAVN cases with nephrotic state (serum albumin [sAlb]<3.0g/dL and urine protein-creatinine ratio of >2.0 g/ gCr) without kidney injury treated at our hospital between 2010 and 2018.

RESULTS

Of the 216 patients with IgAVN identified, 17 met the inclusion criteria. The median follow-up period from disease onset to the last observation was 40.5 months (IQR:31.0-74.2). Eleven patients were male, the median age at onset was 5 years, the minimum serum Alb level was 1.9 g/dL, the maximum proteinuria value was 12.3 g/gCr, and the median minimum eGFR was 86.0 mL/min/1.73 m² in the acute phase. Eight patients (47%) achieved resolution of nephrotic state within three months and complete remission without treatment by the last observation. The patients with spontaneous resolution of nephrotic state had less severe hypoalbuminaemia (Alb<2.0g/dL) and tended to show a quick increase in the serum albumin level.

CONCLUSIONS

Our study found that half of paediatric patients with IgAVN with nephrotic state achieved spontaneous resolution without treatment and enjoyed a favorable short-term outcome. Consideration of the duration of nephrotic state and trends in the serum albumin level in children with IgAVN may allow unnecessary kidney biopsies and immunosuppressive therapy to be avoided. This article is protected by copyright. All rights reserved.

IgA vasculitis with nephritis: update of pathogenesis with clinical implications

IgA vasculitis with nephritis (IgAVN) shares many pathogenetic features with IgA nephropathy (IgAN). The purpose of this review is to describe our current understanding of the pathogenesis of pediatric IgAVN, particularly as it relates to the four-hit hypothesis for IgAN. These individual steps, i.e., hits, in the pathogenesis of IgAN are (1) elevated production of IgA1 glycoforms with some O-glycans deficient in galactose (galactose-deficient IgA1; Gd-IgA1), (2) generation of circulating IgG autoantibodies specific for Gd-IgA1, (3) formation of pathogenic circulating Gd-IgA1-containing immune complexes, and (4) kidney deposition of the Gd-IgA1-IgG immune complexes from the circulation and induction of glomerular injury. Evidence supporting the four-hit hypothesis in the pathogenesis of pediatric IgAVN is detailed. The genetics, pediatric outcomes, and kidney histopathologic features and the impact of these findings on future treatment and potential biomarkers are discussed. In summary, the evidence points to the critical roles of Gd-IgA1-IgG immune complexes and complement activation in the pathogenesis of IgAVN. Future studies are needed to characterize the features of the immune and autoimmune responses that enable progression of IgA vasculitis to IgAVN.

IgA vasculitis nephritis

PURPOSE OF REVIEW

The purpose of this update is to summarize current knowledge on the pathophysiology of immunglobulin A (IgA) vasculitis nephritis (IgAVN) as well as to critically review evidence for established therapeutic regimes and available biomarkers. An additional purpose is to raise the discussion what could be done to further improve our understanding of IgAVN, identify patients at risk for adverse outcome and increase the evidence for therapy recommendations.

RECENT FINDINGS

Clinical and experimental studies have established the concept of a multilevel pathogenesis. Toll-like-receptor activation, B cell proliferation, micro-RNAs and complement activation have been identified or confirmed as potential therapeutic targets which can modify the course of the disease. Currently, kidney injury molecule-1, monocyte chemotactic protein-1, N-acetyl-β-glucosaminidase, and angiotensinogen are the most promising urinary biomarkers for early diagnosis of renal involvement in IgA vasculitis.

SUMMARY

Close surveillance of all IgAV patients for renal involvement is recommended. Given the multilevel pathogenesis, early treatment of even mild cases should be initiated. Further therapeutic options should be considered in case first-line therapy (mostly corticosteroids) has no effect. The evidence supporting current therapeutic regimes is predominantly based on expert opinion. Prospective studies are needed and should involve substances inhibiting B cell proliferation and complement activation.

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.

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.

Association of kidney biopsy findings with short- and medium-term outcomes in children with moderate-to-severe IgA vasculitis nephritis

Assessing the initial severity of immunoglobulin A vasculitis nephritis (IgAV-N) is important due to its determining effect on kidney management and outcomes. This paper describes a multicentre paediatric cohort of IgAV-N patients and discusses relationships among clinical presentation, histological features, and kidney outcome. We retrospectively studied a cohort of 170 children with biopsy-proven IgAV-N, diagnosed between 2007 and 2017. One-quarter of the cohort (27%) presented with initial nephrotic syndrome (NS). Kidney biopsy revealed International Study of Kidney Disease (ISKDC) grade II or grade III in 83% of cases. Endocapillary proliferation was observed in 73% of patients, and chronic lesions were observed in 25%. Data analysis showed a significant association between NS at onset and endocapillary proliferation and cellular crescents. After a median follow-up of 21 months (IQR 12-39), 30% of patients had persistent proteinuria or decreased eGFR. At the end of follow-up, kidney impairment was more often observed in patients with NS at onset and those with cellular crescents and chronic lesions on initial kidney biopsy.Conclusion: This study highlights the relationship between the clinical and histological presentation of IgAV-N and the factors that affect kidney outcome. The ISKDC classification may be improved by including lesions that are more discriminating for disease severity and prognosis. What is Known: • Nephrotic syndrome (NS) or kidney failure at diagnosis and cellular crescents in more than 50% of the glomeruli are recognized as risk factors for poor kidney outcome in immunoglobulin A vasculitis nephritis (IgAV-N). • The reference histological classification of the International Study of Kidney Disease in Children (ISKDC) is primarily based on the presence and number of affected glomeruli (mesangial proliferation, cellular crescents). The updated Oxford classification, which emphasizes tubular atrophy and interstitial fibrosis, is also used to group pathological features of IgAV-N. Both classifications have limitations. What is New: • Medical treatment should not be postponed in patients with IgAV-N and NS until after biopsy, as NS at diagnosis is associated with initial histological severity and poorer kidney outcome. This proposal needs to be verified in further studies. • Endocapillary proliferation is associated with the initial severity of IgAV-N at diagnosis, while chronic glomerular changes and interstitial fibrosis are associated with poorer short- and medium-term kidney outcomes.

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.

Using MEST-C Scores and the International Study of Kidney Disease in Children Classification to Predict Outcomes of Henoch-Schönlein Purpura Nephritis in Children

Introduction: Henoch-Schönlein purpura nephritis (HSPN) and IgA nephropathy (IgAN) bear similarities in some aspects. The histological classification of HSPN was built on the International Study of Kidney Disease in Children (ISKDC) criteria, while IgAN was established on the 2016 Oxford classification (MEST-C scores). The purpose of this paper was to discuss the predictive value of the ISKDC classification and MEST-C scores in children with HSPN. Methods: We performed a retrospective study of 877 children with HSPN in a single center between 2001 and 2019. The primary outcome was defined as chronic kidney disease-estimated glomerular filtration rate (eGFR) <90 ml/min/1.73 m². Results: During the follow-up period of 23.3 (10.9-47.9) months, 51 (5.8%) patients reached the primary outcome. As revealed in a Kaplan-Meier plot, segmental glomerulosclerosis (S) (P < 0.001) and tubular atrophy/interstitial fibrosis (T) (P < 0.001) significantly predict poor renal outcome. Other Oxford lesions and the ISKDC classification, however, did not show a significant difference in a worse outcome. In a multivariate Cox model adjusted for pathological and clinical factors, eGFR [hazard ratio (HR) = 2.831, 95% confidence interval (95% CI) = 1.359-5.896], S lesion (HR = 3.936, 95% CI = 2.078-7.457), and T lesion (HR = 4.002, 95% CI = 1.733-9.242) were independent risk factors for the renal outcome. Conclusion: This series constitutes the largest series reported so far in the literature of such patients. According to our findings, S and T of the Oxford classification, which are ignored by the ISKDC classification, could be applied to predict the renal prognosis of children with HSPN.

A systematic review of urine biomarkers in children with IgA vasculitis nephritis

BACKGROUND

Nephritis is a recognised complication of IgA vasculitis (IgAV, Henoch-Schönlein purpura) contributing to 1-2% of all chronic kidney disease (CKD) stage 5. Improved understanding may reduce irreversible damage in IgAV nephritis (IgAV-N).

OBJECTIVE

The aim of this study was to perform a comprehensive systematic literature review to identify promising clinical and pre-clinical urine biomarkers in children with IgAV-N that could predict the presence of nephritis and/or determine its severity.

METHODS

A systematic literature review was performed using four search engines and a predefined search term strategy. Promising biomarkers were divided in terms of clinical or pre-clinical and ability to predict the presence of nephritis or determine its severity. Results were described using statistical significance (p < 0.05) and area under the curve (AUC) values.

RESULTS

One hundred twenty-one studies were identified; 13 were eligible. A total of 2446 paediatric patients were included: healthy controls (n = 761), children with IgAV-N (n = 1236) and children with IgAV without nephritis (IgAV-noN, n = 449). Fifty-one percent were male, median age 7.9 years. The clinical markers, 24-h protein quantity and urine protein:creatinine ratio, were deemed acceptable for assessing severity of nephritis (AUC < 0.8). Urinary albumin concentration (Malb) performed well (AUC 0.81-0.98). The most promising pre-clinical urinary biomarkers in predicting presence of nephritis were as follows: kidney injury molecule-1 (KIM-1) (AUC 0.93), monocyte chemotactic protein-1 (MCP-1) (AUC 0.83), N-acetyl-β-glucosaminidase (NAG) (0.76-0.96), and angiotensinogen (AGT) (AUC not available). Urinary KIM-1, MCP-1, and NAG appeared to correlate with disease severity.

CONCLUSIONS

Longitudinal studies are needed to assess whether pre-clinical biomarkers enhance standard of care in IgAV-N.

Obesity is associated with severe clinical course in children with Henoch-Schonlein purpura

BACKGROUND

We aimed to evaluate the role of obesity on the clinical course and response to treatment in patients with Henoch-Schonlein purpura (HSP).

METHODS

Data charts of children with HSP followed in a tertiary hospital between 2000 and 2018 were reviewed retrospectively. Persistent purpura was defined as skin involvement persisting for ≥ 30 days. Mild nephropathy was defined as the presence of microscopical hematuria and/or non-nephrotic proteinuria, while severe nephropathy as nephrotic proteinuria, nephritic syndrome, and/or kidney insufficiency. Obese and non-obese patients were compared for demographic, clinical, and laboratory parameters.

RESULTS

There were 199 patients (M/F, 104/95; median (IQR) presenting age 7.1 (5.0-9.2) years; follow-up period 17.5 (6-50) months). Obese patients (n = 35 (17.6%)) had significantly higher rate of persistent purpura (46% vs 21%), severe renal involvement (58% vs 31%), high-grade renal histopathological lesions (83% vs 39%), hypertension (29% vs 9%), and increased erythrocyte sedimentation rate (79% vs 56%). Obese patients also showed delayed improvement of cutaneous (25 vs 14 days), articular (12.5 vs 10.0 days), and kidney (280 vs 57 days) symptoms. Obese children used steroids for significantly longer period of time (236 vs 40 days). Furthermore, need for immunosuppressive medications were higher in obese patients (40% vs 9%).

CONCLUSIONS

Obese children with HSP had higher erythrocyte sedimentation rate, hypertension, and severe renal involvement; showed delayed improvement of skin, joint, and kidney findings; and need more immunosuppressive medications and a longer period of steroid treatment. These findings may be associated with the effect of adipose tissue on inflammation.

Risk factors associated with renal crescentic formation in pediatric Henoch-Schönlein purpura nephritis: a retrospective cohort study

BACKGROUND

The long-term prognosis of Henoch-Schönlein purpura (HSP) depends on the severity of renal involvement, and crescent formation is considered an important risk factor for poor prognosis of Henoch-Schönlein purpura nephritis (HSPN). The objective of this study was to evaluate factors affecting crescent formation in children with HSPN.

METHODS

Demographic factors, clinical characteristics, and laboratory data of children with HSPN with or without crescents were retrospectively analyzed. Univariate and multivariate logistic regression analyses were used to determine the risk factors of crescent formation in HSPN.

RESULTS

A total of 191 children with HSPN were enrolled in the study. There were 107 (56%) males and 84 (44%) females, with a median age of 7 years (range: 2 years-15 years). International Study of Kidney Disease in Children (ISKDC) grading was used to divide subjects into two groups: those without glomerular crescent formation (ISKDC grades I-II, n = 146 cases) and those with glomerular crescent formation (ISKDC grades III-V, n = 45 cases). Logistic regression analysis showed that higher urinary white blood cell (WBC) count (OR = 3.300; 95% CI, 1.119-9.739; P = 0.0306) and higher urinary microalbumin/creatinine ratio (ACR) (OR = 25.053; 95% CI, 1.354-463.708; P = 0.0305) were independent risk factors for the formation of crescents in HSPN. The area under the receiver operating characteristic curve of urinary WBC and ACR were 0.753 and 0.698 respectively, with the Hosmer and Lemeshow goodness-of-fit test (P = 0.0669, P > 0.05).

CONCLUSION

These results suggest that higher urinary WBC count and ACR should be strictly monitored for children with HSPN. Adequate clinical intervention for these risk factors may limit or prevent renal crescent formation.

Patient Outcomes of Henoch-Schönlein Purpura Nephritis According to the New Semiquantitative Classification

Background: A new semiquantitative classification (SQC) for pediatric Henoch-Schönlein nephritis (HSN) was defined recently. The outcomes of pediatric HSN patients are reevaluated according to the new classification. Methods: Primary kidney biopsies from 80 HSN patients were scored using the new SQC. The International Study of Kidney Disease in Children (ISKDC) and SQC classifications were compared in terms of the patient outcomes. Outcomes were defined as: Outcome A (n = 44) patients with no sign of renal disease, Outcome B (n = 32) patients with minor urinary abnormalities, and Outcome C (n = 4) patients with active renal disease. Results: The patients with outcome C had significantly higher biopsy scores and chronicity indices than patients in group A. There was no significant difference in areas under the curve between total biopsy SQC scores and ISKDC findings. Conclusions: Our results suggest that the modified SQC is not more sensitive than ISKDC classification for predicting the outcome in HSN cases.

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.

Clinical relevance of membrane attack complex deposition in children with IgA nephropathy and Henoch-Schönlein purpura

BACKGROUND

IgA nephropathy (IgAN) and Henoch-Schönlein purpura are common glomerular disorders in children sharing the same histopathologic pattern of IgA deposits within the mesangium, even if their physiopathology may be different. Repeated exposure to pathogens induces the production of abnormal IgA1. The immune complex deposition in the renal mesangium in IgAN or potentially in small vessels in Henoch-Schönlein purpura induces complement activation via the alternative and lectin pathways. Recent studies suggest that levels of membrane attack complex (MAC) in the urine might be a useful indicator of renal injury. Because of the emerging availability of therapies that selectively block complement activation, the aim of the present study is to investigate whether MAC immunostaining might be a useful marker of IgA-mediated renal injury.

METHODS

We conducted immunohistochemistry analysis of the MAC on renal biopsies from 67 pediatric patients with IgAN and Henoch-Schönlein purpura. We classified their renal biopsies according to the Oxford classification, retrieved symptoms, biological parameters, treatment, and follow-up.

RESULTS

We found MAC expression was significantly related to impaired renal function and patients whose clinical course required therapy. MAC deposits tend to be more abundant in patients with decreased glomerular filtration rate (p = 0.02), patients with proteinuria > 0.750 g/day/1.73 m², and with nephrotic syndrome. No correlation with histological alterations was observed.

CONCLUSIONS

We conclude that MAC deposition could be a useful additional indicator of renal injury in patients with IgAN and Henoch-Schönlein purpura, independent of other indicators.

Epidemiology of 10-year paediatric renal biopsies in the region of southern Croatia

Background

Information about renal diseases in children is available from national registries of renal biopsies. Aim of the study was to compare the clinical presentation of glomerular diseases and tubulointerstitial space diseases with pathohistological diagnosis of indicated renal biopsies from pediatric population in the Croatian region of Dalmatia.

Methods

Out of 231 pediatric patients with suspected glomerular and tubulointerstitial diseases, 54 underwent ultrasound-guided renal biopsy at University Hospital of Split. Kidney allograft biopsy, and re-biopsy were excluded. The biopsy sections were examined under light microscopy, immunofluorescence and electron microscopy. The data was reviewed to determine the pathohistological spectrum and clinicopathologic correlations. We retrospectively analyzed kidney biopsy data from 2008 to 2017 and compared them to that between 1995 and 2005.

Results

The mean age of patients was 9.84 ± 5.4 years. Male:female ratio was 1.2:1. The main indications for biopsy were pure nephrotic syndrome without hematuria (25.9%), non-nephrotic proteinuria with haematuria (22.2%), nephritic syndrome with nephrotic proteinuria (18.5%), and isolated hematuria (16.7%). The most common pathohistological findings were IgA nephropathy (IgAN, 24.1%), minimal change disease (MCD, 16.7%), Henoch-Schönlein purpura glomerulonephritis (HSPN, 14.8%), Alport syndrome and focal segmental glomerulosclerosis (AS and FSGS, 11.1% each), tubulointerstitial nephritis and membranous glomerulopathy (TIN and MGN, 3.7% each), while other cases were diagnosed rarely.

Conclusions

Changes in epidemiology of renal diseases in children between the analyzed periods showed an increasing trend of IgAN, MCD, HSPN, AS and FSGS, while mesangioproliferative glomerulonephritis (MesPGN) and endoproliferative glomerulonephritis (EDGN) showed a decreasing trend that can be explained with the new pathohistological classification.

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.

Clinical manifestations and outcomes of 420 children with Henoch Schönlein Purpura from a single referral center from Turkey: A three-year experience

Objectives: Henoch Schönlein Purpura (HSP) is the most common systemic vasculitis in childhood. We aimed to evaluate the clinical features, seasonal variation, treatment outcomes and the possible predicting factors related to outcome among a large cohort of pediatric HSP patients.Methods: We conducted a medical record review study between July 2016 and January 2019 and evaluated the clinical manifestations and potential risk factors for severe gastrointestinal (GI) involvement, biopsy-proven nephritis and relapses.Results: The study included 420 HSP patients, of which the mean age at diagnosis was 7.68 ± 3.15 years. Clinical manifestations were arthralgia and/or arthritis (n = 244, 58.1%), abdominal pain (n = 235, 56%), subcutaneous edema (n = 163, 38.8%), and renal involvement (n = 125, 29.8%). Disease recurred for at least once, in 69 (16.4%) patients and colchicine treatment yielded a favorable response in 11 of 12 relapsing patients, who did not respond to ibuprofen or steroids. Frequencies of renal involvement and biopsy-proven nephritis were higher in patients with severe GI involvement. Besides, patients with biopsy-proven nephritis had higher rates of abdominal pain, intussusception, severe GI involvement, and systemic steroid administration.Conclusion: We speculate that renal involvement, biopsy-proven nephritis and severe GI involvement can be related to each other. Colchicine may be effective in patients with relapsing disease.

Changes of inflammatory mediators and oxidative stress indicators in children with Henoch-Schönlein purpura and clinical effects of hemoperfusion in the treatment of severe Henoch-Schönlein purpura with gastrointestinal involvement in children

BACKGROUND

To explore the changes of inflammatory and oxidative stress responses in Henoch-Schönlein purpura (HSP) children, and further analyzed the therapeutic effects and mechanisms of hemoperfusion (HP) on HSP with severe gastrointestinal (GI) involvement.

METHODS

There were 200 children with HSP were divided into three groups according to their clinical manifestations: 60 in HSP without GI and renal involvement group, 60 in HSP with GI involvement group, and 80 in HSPN group. The HSP with GI involvement group was subdivided into conventional treatment (n = 30) and HP (n = 30) groups. Thirty children who visited the department of children healthcare for healthy physical examinations from January to December 2017 were set as healthy control group. The IL-6 and TNF-α levels were detected by chemoluminescence method. The MDA, SOD and T-AOC levels were determined by thiobarbituric acid colorimetric method, hydroxylamine method and chemical colorimetry.

RESULTS

Compared with healthy group, IL-6, TNF-α and MDA levels in HSP were increased in each group, while SOD and T-AOC were decreased (P = 0.000). IL-6, TNF-α and MDA levels in the HSPN group were the highest, SOD and T-AOC levels were the lowest (P = 0.000). Compared with those before treatment, IL-6, TNF-α and MDA levels in the conventional and HP groups were decreased and SOD and T-AOC levels were increased (P = 0.000). The changes in HP group were more significant than those in conventional group (P < 0.047). Compared with conventional group, glucocorticoid dosage and the occurrence rate of hematuria and/or proteinuria within 3 months were lower in HP group. (P = 0.000, 0.004).

CONCLUSIONS

Inflammatory and oxidative stress may be involved in the acute phase of HSP children. The intensity of inflammatory and oxidative stress responses were related to the degree of renal involvement. HP can reduce glucocorticoid dosage and the rate of renal involvement in children with severe HSP with GI involvement. The mechanism may be related to the fact that HP can effectively remove IL-6, TNF-α, MDA in HSP children.

Risk factors associated with IgA vasculitis with nephritis (Henoch-Schönlein purpura nephritis) progressing to unfavorable outcomes: A meta-analysis

OBJECTIVE

To identify risk factors associated with unfavorable outcomes in children with IgA vasculitis with nephritis (Henoch-Schőnlein purpura nephritis)(IgA-VN).

METHODS

PubMed, Embase, and Web of Science databases were searched for studies, published in English through February 2019. The data were extracted to perform pooled analysis, heterogeneity testing, subgroup analysis, sensitivity analysis, and publication bias analysis.

RESULTS

This meta-analysis showed that, older age at onset (WMD 1.77, 95% CI 0.35-3.18, p = 0.014), lower glomerular filtration rate (GFR; WMD -23.93, 95% CI -33.78- -14.09, p<0.0001), initial renal manifestations with nephrotic syndrome (OR 1.74, 95% CI 1.12-2.70, p = 0.013), with nephritic-nephrotic syndrome (OR 4.55, 95% CI 2.89-7.15, p<0.0001) and renal biopsy with crescentic nephritis (International Study of Kidney Disease in Children [ISKDC] grades III-V) (OR 3.85, 95% CI 2.37-6.28, p<0.0001) were significant risk factors associated with poor outcomes in IgA-VN, whereas initial clinical features with hematuria (OR 0.33, 95% CI 0.16-0.69, p = 0.003) and mild proteinuria±hematuria (OR 0.46, 95% CI 0.28-0.75, p<0.0001) were associated with progression to good outcomes. By contrast, gender, hypertension and initial renal manifestations of acute nephritic syndrome were not significantly associated with poor outcomes in IgA-VN.

CONCLUSION

This meta-analysis showed that older age at onset, lower GFR, initial renal features of nephrotic syndrome and nephritic-nephrotic syndrome and renal biopsy with crescentic nephritis (ISKDC grades III-V) were predictive of poor prognosis in children with IgA-VN.

Updated Oxford classification and the international study of kidney disease in children classification: application in predicting outcome of Henoch-Schönlein purpura nephritis

Background

Henoch-Schönlein purpura nephritis (HSPN) shares many similarities with IgA nephropathy. We aimed to analyze the predictive value of the International Study of Kidney Disease in Children (ISKDC) classification and the updated Oxford classification for IgA nephropathy in HSPN patients.

Methods

Data of 275 HSPN patients (aged≥14 years) were retrieved, and all of them underwent a renal biopsy. We re-classified the biopsies according to the ISKDC classification and the updated Oxford classification to analyze their correlations with clinical features and renal outcomes. The renal endpoints were defined as ≥30% reduction in baseline estimated glomerular filtration rate (eGFR) in 2 years, doubling of serum creatinine (Scr) or end stage renal disease.

Results

During follow-up period of 56(30,86) months, 30(10.9%) patients reached renal endpoints. Segmental sclerosis was the only pathological feature independently associated with renal endpoints (HR 4.086, 95%CI 1.111–15.026, P = 0.034). Tubular atrophy/ interstitial fibrosis was associated with eGFR and Scr levels, and its correlation with renal endpoints was found by univariate analysis. Endocapillary hypercellularity was associated with 24 h urine protein and is of prognostic value in univariate analysis. Mesangial hypercellularity was not associated with clinical features or renal endpoints. Crescents were associated with 24 h urine protein, Scr and eGFR levels, but both ISKDC and updated Oxford classifications of crescents were not associated with renal endpoints by multivariate analysis.

Conclusions

The updated Oxford classification can help in disease management and renal outcome prediction of HSPN.

Electronic supplementary material

The online version of this article (10.1186/s13000-019-0818-0) contains supplementary material, which is available to authorized users.

European consensus-based recommendations for diagnosis and treatment of immunoglobulin A vasculitis—the SHARE initiative

Objectives

IgA vasculitis (IgAV, formerly known as Henoch–Schönlein purpura) is the most common cause of systemic vasculitis in childhood. To date, there are no internationally agreed, evidence-based guidelines concerning the appropriate diagnosis and treatment of IgAV in children. Accordingly, treatment regimens differ widely. The European initiative SHARE (Single Hub and Access point for paediatric Rheumatology in Europe) aims to optimize care for children with rheumatic diseases. The aim therefore was to provide internationally agreed consensus recommendations for diagnosis and treatment for children with IgAV.

Methods

Recommendations were developed by a consensus process in accordance with the EULAR standard operating procedures. An extensive systematic literature review was performed, and evidence-based recommendations were extrapolated from the included papers. These were evaluated by a panel of 16 international experts via online surveys and subsequent consensus meeting, using nominal group technique. Recommendations were accepted when ⩾80% of experts agreed.

Results

In total, 7 recommendations for diagnosis and 19 for treatment of paediatric IgAV were accepted. Diagnostic recommendations included: appropriate use of skin and renal biopsy, renal work-up and imaging. Treatment recommendations included: the importance of appropriate analgesia and angiotensin-converting enzyme inhibitor use and non-renal indications for CS use, as well as a structured approach to treating IgAV nephritis, including appropriate use of CS and second-line agents in mild, moderate and severe disease along with use of angiotensin-converting enzyme inhibitors and maintenance therapy.

Conclusion

The SHARE initiative provides international, evidence-based recommendations for the diagnosis and treatment of IgAV that will facilitate improvement and uniformity of care.

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

BACKGROUND

Nephritis is the most important chronic complication of IgA Vasculitis (IgAV)/Henoch-Schönlein purpura (IGAV/HSP) and thus the main prognostic factor of this most common childhood vasculitis. Since the prognosis and treatment selection depends on the mode of interpretation of biopsy material, in this manuscript we have presented several issues related to the uneven application of different histological classifications in IgAV/Henoch-Schönlein purpura nephritis (HSPN). The nephritis of IgAV/IGAV/HSP will be abbreviated as HSPN for this paper.

MAIN BODY

In clinical practice we use different histological classifications for HSPN. It is not known which of these classifications best correlates with severity of renal disease and renal outcome in IgAV/IGAV/HSP. One of the major problem with existing histological classifications is that there is no consensus on the implementation of biopsy in the treatment of HSPN. There is a histologic classification system conventionally used in HSPN, of the International Study of Kidney Disease in Children (ISKDC). On the other hand there is the new classification system suggested for IgA nephropathy, the Oxford classification. The latter has been validated only in IgA nephropathy. There are also two further histologic classifications of Haas and Koskela that have been developed. Current treatment strategies in HSPN are not standardised nor predominantly based on histological classification.

CONCLUSION

One of the possible solutions to problems related to the application of different histological classification in HSPN is the implementation of multicenter multinational prospective studies with joint collaboration between pediatric rheumatologists, nephrologists and nephropathologists to correlate the clinical features and outcome with the classification systems as well among the classifications. This classification should be the basis for the construction of guidelines for the treatment of patients with HSPN.

Tubulointerstitial Infiltration of M2 Macrophages in Henoch-Schönlein Purpura Nephritis Indicates the Presence of Glomerular Crescents and Bad Clinical Parameters

Henoch-Schönlein purpura (HSP) is the most common systemic vasculitis in children, and renal involvement (HSP nephritis, HSPN) is a severe manifestation. HSPN is histologically classified by the International Study of Kidney Disease in Children (ISKDC) based on mesangial hypercellularity and the extent of glomerular crescents. Macrophages, categorized as M1 or M2, frequently infiltrate in various glomerular and tubulointerstitial diseases and infiltration of specific subtypes is associated with disease progression. Therefore, to identify whether infiltration of M1 or M2 macrophages has clinical significance, we quantified the subtypes of macrophages in 49 HSPN specimens and correlated the counts with histologic features and clinical parameters. Higher tubulointerstitial M2 counts were associated with chronic renal failure (CRF), ISKDC classes III-IV, and crescents (P<0.001, 0.002, 0.001). Glomerular M2 counts were significantly related to ISKDC classes III-IV and crescents (area under curve, AUC 0.804, 0.833). Tubulointerstitial M2 counts were associated with CRF, ISKDC classes III-IV, and crescents (AUC 0.872, 0.778, 0.830). Tubulointerstitial M2 counts also revealed higher AUC than tubulointerstitial M1 counts for CRF (P=0.036) and ISKDC classes III-IV (P=0.047). Glomerular M2 counts revealed higher AUC than glomerular M1 counts for ISKDC classes III–IV (P=0.024). Tubulointerstitial M2 counts were the most powerful parameter for CRF (AUC 0.872) and revealed even higher AUC than ISKDC classification (AUC 0.716) with borderline significance (P=0.086) for CRF. In summary, tubulointerstitial M2 counts were a superior parameter to tubulointerstitial M1 counts and even to ISKDC classification indicating the presence of CRF.