Risk Factors Associated with Renal Involvement in Childhood Henoch-Schönlein Purpura: A Meta-Analysis

Immunoglobulin a vasculitis with central nervous system involvement: analysis of 10 cases

Immunoglobulin A vasculitis (IgAV) is a systemic inflammatory disease that affects small blood vessels. Central nervous system (CNS) involvement in IgAV is rare. This study analyzed the clinical characteristics of IgAV patients combined with CNS damage in children. Furthermore, the study made a comparison between the characteristics of IgAV patients with and without CNS damage, and initially explored the potential predictors for IgAV patients with CNS damage. A retrospective analysis was conducted on a cohort of 50 children diagnosed with IgAV and admitted to Beijing Children's Hospital from 2016 to 2019. The study encompassed a review of the clinical presentations, laboratory test results, imaging findings, therapeutic interventions, and prognoses of 10 children with IgAV who exhibited CNS involvement. These 10 cases were then compared with a group of 40 children with IgAV without CNS involvement. The prevalence of IgAV with CNS manifestations was 0.2%. The median age was 11.6 years, with a male-to-female ratio of 7:3. All CNS symptoms appeared after the purpuric rash. The mean period from IgAV onset to the development of neurological symptoms was 12.2 days (range: 1-27 days). Seizures were the most common neurological manifestation, with impaired consciousness and predominant convulsions. Other symptoms included headache, visual impairment, dysarthria, dyskinesia, and emotional irritation. The main abnormalities found on brain magnetic resonance imaging (MRI) were unilateral or bilateral abnormal focal signals, cortical and subcortical white matter edema, and thrombosis of the venous sinus. Glucocorticoid therapy and intravenous immunoglobulins were used to treat CNS damage caused by IgAV. All patients showed clinical improvement without recurrent neurological symptoms or sequelae. Statistically differences were identified in in terms of age, gastrointestinal damage, WBC count, NLR, ALB, C3 levels, and the CD4/CD8 ratio in IgAV patients with CNS damage when compared to those without CNS damage. Multivariable logistic regression analysis shows that age, NLR and C3 Levels are predictors of IgAV with CNS damage. CNS involvement in IgAV is a rare complication. Its clinical manifestations are diverse and vary in severity, and its diagnosis is exclusionary. Brain MRI is beneficial for diagnosis and follow-up. Steroid therapy is important for treating IgAV-associated CNS involvement. Age, NLR and C3 Levels are predictors of IgAV with CNS damage.

Gastrointestinal features of pediatric iga vasculitis and their association with renal complications: an observational study

Immunoglobulin A (IgA) vasculitis is the most common systemic vasculitis in childhood, primarily affecting the skin, gastrointestinal system (GIS), joints, and kidneys. This study aimed to evaluate the clinical and laboratory characteristics of mild and severe GIS involvement in pediatric patients with IgA vasculitis and to investigate its association with renal involvement. A retrospective review was conducted on 794 pediatric patients diagnosed with IgA vasculitis between 1997 and 2024. Demographic data, clinical findings, and laboratory parameters were collected from patient records. GIS involvement was classified as mild (abdominal pain, vomiting, or occult blood in stool) or severe (melena, hematochezia, or intussusception). Renal involvement was defined based on hematuria, proteinuria, hypertension, or renal insufficiency. Among 794 patients, 430 (54.2%) were male, with a mean age at diagnosis of 7.8 ± 3.3 years. GIS involvement was observed in 422 (53.1%) patients, of whom 333 (78.9%) had mild GIS involvement and 89 (21.1%) had severe GIS involvement. Renal involvement was detected in 171 (21.5%) patients, and was more frequent in those with GIS involvement (26.3% vs. 16.1%, p = 0.001). GIS (55.6% (n = 306) vs. 47.1% (n = 115)) and renal (24.5% (n = 134) vs. 15.2% (n = 37)) involvement were more common in patients aged > 5 years than in patients ≤ 5 years (p = 0.027, p = 0.004, respectively). GIS involvement was significantly associated with leukocytosis (p < 0.001) and elevated C-reactive protein (CRP) (p = 0.018), but these parameters did not correlate with renal involvement. Patients with positive fecal occult blood tests had a significantly higher risk of renal involvement (p < 0.001). However, there was no significant difference in renal involvement between patients with mild and severe GIS involvement (p = 0.082).

CONCLUSION

GIS involvement, older age (> 5 years), and the presence of occult blood in stool were associated with a higher likelihood of renal involvement in pediatric IgA vasculitis. However, the severity of GIS involvement did not correlate with renal involvement, suggesting that renal pathology may be influenced by independent mechanisms rather than the severity of GIS symptoms.

WHAT IS KNOWN

• Older age, persistent palpable purpura, abdominal pain, GIS involvement, recurrent disease episodes are risk factors for renal involvement in IgA vasculitis.

WHAT IS NEW

• GIS involvement, fecal occult blood positivity, and age over five years were significantly associated with renal involvement in pediatric IgA vasculitis. However, the severity of GIS involvement did not predict the presence or severity of renal involvement.

Proteomic analysis of urine reveals biomarkers for identification of kidney injury in children's abdominal-type Henoch-Schönlein purpura

BackgroundAbdominal Henoch - Schönlein purpura (AHSP), being the most prevalent form of Henoch - Schönlein purpura, has a significant impact on the short - term prognosis of the disease and often involves the kidneys, leading to renal complications that affect children's long - term prognosis. However, the existing early assessment criteria for AHSP and its renal complications are inadequate. The urinary proteome may offer valuable insights.ObjectiveTo confirm the significance of urinary proteomics in the early detection of AHSP and its renal complications in children.MethodsThe urinary proteome of AHSP patients (with and without renal involvement) was compared with that of healthy controls using liquid chromatography - tandem mass spectrometry (LC - MS/MS) in data - independent acquisition (DIA) mode. Differentially expressed proteins were analyzed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Mfuzz was employed to analyze the expression levels of proteins related to disease onset and progression. The STRING database was used for protein - protein interaction analysis of relevant biological pathways. Selected differential proteins were verified using parallel reaction monitoring (PRM).ResultsA total of 441 dysregulated differentially expressed proteins (DEPs) were associated with the pathogenesis of AHSP, mainly related to cell adhesion, signal transduction or regulation, and reactions or pathways mediated by inflammatory cells or factors, and predominantly enriched in the lysosomal pathway. A total of 275 DEPs related to renal complications of AHSP were mainly associated with immune processes mediated by immunoglobulins, predominantly enriched in the regulatory pathways of the actin cytoskeleton. Time series clustering analysis identified 10 discrete clusters; three upregulated and two downregulated clusters were chosen to form respective panels. These panels involved various biological processes such as immune and inflammatory processes, lipid metabolism, glycosylation, coagulation, oxidative detoxification processes, and the Wnt signaling pathway, with several important biological pathways being enriched. Protein - protein interaction analysis of key pathways revealed three distinct MCODE networks, mainly involving proteins related to immunity, coagulation, collagen, and integrins. In the validation phase, at least eight urinary proteins useful for diagnosing AHSP or its renal complications were identified, demonstrating good diagnostic performance.ConclusionThis study offers novel perspectives on the pathogenesis of AHSP and its renal complications in children, and the related proteins may serve as potential biomarkers for diagnosing AHSP and identifying the onset of renal damage. The findings of this study emphasize the importance of urinary proteomics in understanding the disease mechanisms and provide a basis for further research on early diagnosis and treatment.

[Correlation between streptococcal infection and renal damage in children with Henoch-Schönlein purpura nephritis]

OBJECTIVE

To explore whether streptococcal infection may aggravate renal damage in children with Henoch-Schönlein purpura nephritis and its possible mechanism.

METHODS

In the study, 485 children diagnosed with Henoch-Schönlein purpura nephritis from July 2015 to December 2019 were selected to analyze their clinical data retrospectively. According to the diagnosis of discharge, whether it was combined with streptococcal infection, the children were divided into two groups. The experimental group contained 91 children with Henoch-Schönlein purpura nephritis combined with streptococcal infection, and there were 394 children who were not infected with Streptococcus in the control group. Suitable test items were preliminarily selected through artificial neural network, and then data analysis was performed through SPSS 23.0.

RESULTS

The children with Henoch-Schönlein purpura nephritis infected with streptococcus had statistically significant differences compared with the uninfected children in the test items of urine protein, liver and kidney function, immunoglobulin and complement. Anti-streptolysin O had mild correlation with IgG (Spearman r=-0.328), fibrin degradation products (Spearman r=-0.207), total protein (Spearman r=-0.202) and globulin (Spearman r=-0.223). Compared with the children who were not infected with streptococcus, the differences of the average levels of age (P=0.001), IgG (P < 0.001), fibrin degradation products (P=0.019), total protein (P < 0.001), globulin (P < 0.001), IgA (P < 0.001), IgM (P=0.003), complement 3 (P=0.016), complement 4 (P=0.002), albumin/globulin ratio (P=0.007), alkaline phosphatase (P=0.036), and estimated glomerular filtration rate (P=0.039) in the infected children were statistically significant. In order to explore the risk factors of kidney damage in the children with Henoch-Schönlein purpura nephritis, Logistic regression was performed using anti-streptolysin O, age, immunoglobulin and complement as independent variables, urine protein detection parameters, liver and kidney functions as dependent variables. Age ≤10 years old and hypocomplementemia might be risk factors for aggravating renal damage in the children with Henoch-Schönlein purpura nephritis.

CONCLUSION

Streptococcal infections may aggravate renal damage in children with Henoch-Schönlein purpura nephritis, in which hypocomplementemia, inflammation, fibrinolysis and disorders of coagulation perhaps play an important role. Children with streptococcal infection should be treated with anti-infective treatment in time and necessarily, and followed up after discharge regularly.

Association between immune cells and allergic purpura: a Mendelian randomization study

BACKGROUND

Increasing evidence indicates a substantial correlation between the immune cells and the risk of allergic purpura. We utilized Mendelian randomization (MR) to investigate causal effect of immune cell on allergic purpura.

METHODS

Genetic instrumental variables for immune cells were sourced from an extensive genome-wide association study (GWAS) comprising 3757 participants. Summary statistics of allergic purpura, involving 470 cases and 216,099 controls, were obtained from FinnGen. The primary analysis employed the inverse-variance weighted (IVW) method. Rigorous sensitivity analyses including MR-Egger, weighted median and MR-PRESSO were conducted to ensure the reliability of the causal estimate.

RESULTS

We identified two immunophenotypes associated with an increased risk of allergic purpura: HLA-DR on CD14 + CD16- monocyte (OR: 1.2379; 95% CI: 1.0612-1.4440; P = 0.0066) and CD11b on basophil (OR: 1.2973; 95% CI: 1.0905-1.5433; P = 0.0033). The sensitivity analyses consistently yielded similar results for these immunophenotypes.

CONCLUSIONS

Our analyses confirmed a potential causal effect of HLA-DR on CD14 + CD16- monocyte, as well as CD11b on basophils, in relation to the risk of allergic purpura. Further studies are necessary to clarify the mechanisms by which these immunophenotypes influence the development of allergic purpura.

A predictive model to explore risk factors for Henoch-Schönlein purpura nephritis in children: a retrospective cross-sectional study

Objective

The risk factors for Henoch-Schönlein purpura nephritis (HSPN) remain largely unclear, particularly in family environment and vaccination. This study aimed to develop a predictive framework to quantify the risk of HSPN by examining family environmental factors and COVID-19 vaccination outcomes in children with Henoch-Schönlein purpura (HSP) in Anhui, China.

Methods

This study retrospectively analyzed 362 children diagnosed with HSP at Anhui Children's Hospital between January 2020 and February 2024. A questionnaire was designed to collect information from enrolled children. For patients with incomplete medical records, parents were contacted via phone or the questionnaire was sent to them to complete the survey. After data collection, the patients were split randomly into a training group and a validation group at a 7:3 ratio, univariate and multivariate logistic regression analyses were performed to identify risk factors for nephritis, and a nomogram was constructed from these factors to provide a visual prediction of the likelihood of nephritis in HSP. The nomogram's performance was evaluated in both the training and validation groups using the area under the receiver operating characteristic (AUC) curve, calibration plots, and decision curve analysis (DCA).

Results

The study identified family income/month, age of onset, BMI, number of recurrences, and COVID-19 vaccination status as independent risk factors for HSPN. A nomogram was subsequently developed afterward using these factors. In the training group, the nomogram achieved an area under the curve (AUC) of 0.83 (95% CI: 0.78-0.88), while in the validation group, the AUC was 0.90 (95% CI: 0.84-0.96), demonstrating strong predictive performance. The calibration curve showed that the nomogram's predictions were well-aligned with the actual outcomes. Additionally, DCA indicated that the nomogram provided considerable clinical net benefit.

Conclusion

The nomogram offers accurate risk prediction for nephritis in children with HSP, helping healthcare professionals identify high-risk patients early and make informed clinical decisions.

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.

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.

Predicting renal damage in children with IgA vasculitis by machine learning

BACKGROUND

Children with IgA Vasculitis (IgAV) may develop renal complications, which can impact their long-term prognosis. This study aimed to build a machine learning model to predict renal damage in children with IgAV and analyze risk factors for IgA Vasculitis with Nephritis (IgAVN).

METHODS

50 clinical indicators were collected from 217 inpatients at our hospital. Six machine learning algorithms-Logistic Regression, Linear Discriminant Analysis, K-Nearest Neighbor, Support Vector Machine, Decision Trees, and Random Forest-were utilized to select the model with the highest predictive performance. A simplified model was developed through feature importance ranking and validated by an additional cohort with 46 patients.

RESULTS

The random forest model had the highest accuracy, precision, recall, F1 score, and area under the curve, with values of 0.91, 0.98, 0.70, 0.79 and 0.94, respectively. The top 11 features according to the importance ranking were anti-streptolysin O, corticosteroids therapy, antihistamine therapy, absolute eosinophil count, immunoglobulin E, anticoagulant therapy, C-reactive protein, prothrombin time, age at onset, D-dimer, recurrence of rash ≥ 3 times. A simplified model using these features demonstrated optimal performance with an accuracy of 84.2%, a sensitivity of 89.4%, and a specificity of 82.5% in external validation. Finally, we provided a web tool based on the simplified model, whose code was published on https://github.com/mulanruo/IgAVN_Prediction .

CONCLUSION

The model based on the random forest algorithm demonstrates good performance in predicting renal damage in children with IgAV, providing a basis for early clinical diagnosis and decision-making.

Compartment Syndrome: An Uncommon Twist in Childhood Henoch-Schönlein Purpura

Henoch-Schönlein purpura (HSP) also known as rheumatoid purpura is the most common vasculitis in children. This condition affects small blood vessels, predominantly targeting the skin, digestive system, joints, and kidneys. Short-term prognosis mainly depends on abdominal complications, while long-term prognosis is mainly determined by the severity of kidney involvement, which occurs in about 35% of cases. Although uncommon, other organs such as the lungs, heart, or nervous system may also be affected. Compartment syndrome of the hand and forearm is a very rare complication of HSP. To our knowledge, only two cases have been reported in the literature. We describe the case of a four-year-old child who presented with rheumatoid purpura complicated by compartment syndrome of the hand and forearm successfully managed through emergency fasciotomy.

Renal disease in pediatric rheumatology

PURPOSE OF REVIEW

This review will provide updates in the outcomes in the common rheumatologic diseases with kidney involvement. Covered are also advances in therapeutics for the use of pediatric rheumatologic diseases with kidney involvement, as well as the potential kidney complications from other rheumatologic diseases and their medications.

RECENT FINDINGS

Two of the more common rheumatologic diseases with kidney involvement, lupus and vasculitis, continue to show inadequate response to initial therapy of renal disease and practice continues to be driven by results of adult studies.

SUMMARY

There is a continued need for pediatric specific studies in rheumatologic diseases with kidney involvement as outcomes continue to be inadequate. Despite recently approved treatments for adults with rheumatic diseases and kidney involvement, therapeutic options in pediatrics remain limited, contributing to the overall morbidity and mortality.

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.

A Review of IgA Vasculitis (Henoch-Schönlein Purpura) Past, Present, and Future

The clinical association of purpura, arthralgia, and arthritis was first described in 1837 in a publication by Johann Lukas Schönlein, a German physician. In 1874, Eduard Henoch, a student of Schönlein, reported cases of children with purpura, abdominal pain, bloody diarrhea, and joint pain. IgA vasculitis, or Henoch-Schönlein purpura, is a systemic hypersensitivity vasculitis caused by the deposition of immune complexes in small blood vessels, including the renal glomeruli and mesangium. In the skin, the presentation is with non-thrombocytopenic purpura or urticaria. Worldwide, IgA nephropathy is the most common cause of primary glomerulonephritis. Detection of IgA deposition in small blood vessels and the renal glomeruli is diagnostic in most cases. This article aims to review the history, current classification, epidemiology, presentation, and diagnosis of IgA vasculitis and nephropathy, disease associations or trigger factors, including infections, vaccines, and therapeutic agents, and highlights some future approaches to improve diagnosis and clinical management.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Correlation between antiphospholipid antibodies and renal involvement in children with Henoch-Schönlein purpura: A cross-sectional study

Background

Renal involvement is the most damaging long-term complication of Immunoglobulin-A (IgA) vasculitis. In the lack of a definite predictive biomarker for renal involvement, antiphospholipid antibodies (aPL) have been proposed in recent years.

Methods

In this prospective cohort of 48 pediatric patients who were admitted with IgA vasculitis from September 2015 to June 2017, two serum samples were taken 12 weeks apart to detect Anti-Phospholipid antibodies. All patients were followed-up for renal involvement for six months.

Results

Renal involvement occurred in 14 out of 48 patients with IgA vasculitis (29.16%). APLs were positive in nine out of 14 patients with IgA vasculitis and renal involvement (64.28%), in contrast to only six out of 34 patients with IgA vasculitis without renal involvement (17.64%). The presence of aPL antibodies was statistically associated with renal involvement (P=0.002). Although, the relationship between both sex (P=0.025) and age (P=0.046) with aPL positivity was statistically significant, performing a modified logistic regression test, the odds ratio was significant between the groups with and without renal involvement only in term of age and aPL positivity).

Conclusion

The presence of aPL antibodies was statistically associated with renal involvement. We found a significant relationship between the age and aPL positivity. Hence, we need multicenter, more extensive cohort studies to reach a better and more accurate conclusion on the relationship between serum aPLs and renal involvement in IgA vasculitis patients.

Does age at disease onset affect the clinical presentation and outcome in children with immunoglobulin A vasculitis?

Objectives

The study aimed to determine whether there is a relationship between the age at diagnosis and the clinical, laboratory, and prognostic features in pediatric immunoglobulin A vasculitis (IgAV) patients.

Patients and methods

In this study, 539 pediatric IgAV patients (298 males, 241 females; mean age: 7.74±3.36 years; range, 1 to 17.8 years) were retrospectively evaluated between January 2005 and July 2020. The relationship between clinical findings and age at diagnosis was analyzed by univariate logistic regression analysis. Factors associated with renal involvement, steroid-dependent or refractory disease, and recurrence were examined.

Results

The median age of diagnosis was 7.1 (1-17.8) years in all patients. At the time of admission, purpura, abdominal pain, and arthritis were the most common clinical findings. At the time of diagnosis, there was a positive association between age and purpura and an inverse association with the presence of arthritis. There were associations between renal involvement and age at diagnosis (odds ratio=1.22, 95% confidence interval 1.13-1.31, p<0.001), follow-up time (p<0.001), no history of previous infection (p<0.001), and presence of gastrointestinal (GI) involvement (p=0.003). Significant relationships were found between the age at diagnosis, follow-up time, GI involvement, renal involvement, scrotal involvement, the C-reactive protein value at the time of diagnosis, and the presence of steroid-dependent disease. An association was found between recurrence and GI involvement. All refractory patients had renal involvement. Age at diagnosis (p<0.001) and follow-up time (p<0.001) was found to be associated with refractory disease.

Conclusion

Age at diagnosis and follow-up time may be associated with renal involvement and refractory and steroid-dependent disease in IgAV. In addition, there may be a relationship between steroid-dependent disease and renal, GI, and scrotal involvement and between GI involvement and recurrence.

A narrative review of potential drug treatments for nephritis in children with IgA vasculitis (HSP)

Immunoglobulin A (IgA) vasculitis (IgAV, also known as Henoch-Schoenlein purpura, HSP) is the most common vasculitis of childhood. It usually presents with a simple, self-limiting disease course; however, a small subset of patients may develop kidney involvement (IgAV-N) which occurs 4-12 weeks after disease onset and is the biggest contributor to long-term morbidity. Treatment currently targets patients with established kidney involvement; however; there is a desire to work towards early prevention of inflammation during the window of opportunity between disease presentation and onset of significant nephritis. There are no clinical trials evaluating drugs which may prevent or halt the progression of nephritis in children with IgAV apart from the early use of corticosteroids which have no benefit. This article summarises the latest scientific evidence and clinical trials that support potential therapeutic targets for IgAV-N that are currently being developed based on the evolving understanding of the pathophysiology of IgAV-N. These span the mucosal immunity, B-cell and T-cell modulation, RAAS inhibition, and regulation of complement pathways, amongst others. Novel drugs that may be considered for use in early nephritis include TRF-budesonide; B-cell inhibiting agents including belimumab, telitacicept, blisibimod, VIS649, and BION-1301; B-cell depleting agents such as rituximab, ofatumumab, and bortezomib; sparsentan; angiotensin converting enzyme inhibitors (ACE-Is); and complement pathway inhibitors including avacopan, iptacopan, and narsoplimab. Further clinical trials, as well as pre-clinical scientific studies, are needed to identify mechanistic pathways as there may be an opportunity to prevent nephritis in this condition. Key Points • Kidney involvement is the main cause of long-term morbidity and mortality in IgA vasculitis despite the current treatment recommendations. • The evolving understanding of the pathophysiology of IgA vasculitis is allowing exploration of novel treatment options which target underlying immune pathways. • Novel treatments currently being trialled in IgA nephropathy may have benefit in IgA vasculitis due to the similarities in the underlying pathophysiology, such as TRF-budesonide, B-cell modulators, and complement inhibitors. • Further studies, including clinical trials of novel drugs, are urgently needed to improve the long-term outcomes for children with IgA vasculitis nephritis.

Long-term outcome of combination therapy with corticosteroids, mizoribine and RAS inhibitors as initial therapy for severe childhood IgA vasculitis with nephritis

BACKGROUND

Patients with severe IgA vasculitis with nephritis (IgAVN) typically receive aggressive therapy as an initial approach. We have consistently performed combination therapy including corticosteroids and immunosuppressants as initial therapy for severe IgAVN over a 20-year-plus period, with only minor changes to the treatment protocol. This study seeks to reveal the efficacy of combination therapy for severe IgAVN.

METHODS

We retrospectively studied 50 Japanese children diagnosed between 1996 and 2019 with clinicopathologically severe IgAVN who were defined as ISKDC classification grade IIIb-V and/or serum albumin < 2.5 g/dL.

RESULTS

The median age at the onset of IgAVN was 8.0 years (IQR: 6.0-10.0). At biopsy, 44% of patients had nephrotic syndrome and 14% had kidney dysfunction. All patients were treated with combination therapy after biopsy. Abnormal proteinuria resolved after initial therapy in all 50 patients. However, eight patients (16%) had recurrence of proteinuria. Abnormal proteinuria was again resolved in three of these patients with additional treatment. At the last follow-up (median 59.5 months; IQR, 26.2-84.2), the median urine protein-to-creatine ratio was 0.08 g/gCr (IQR, 0.05-0.15), and only one patient had kidney dysfunction.

CONCLUSIONS

Combination therapy provided good kidney outcomes for Japanese children with severe IgAVN. Even including recurrent cases, the degree of proteinuria was slight, and kidney function was good at the last follow-up. A higher resolution version of the Graphical abstract is available as Supplementary information.

A case series on recurrent and persisting IgA vasculitis (Henoch Schonlein purpura) in children

BACKGROUND

IgA vasculitis (IgAV) is a small vessel vasculitis that is more common in childhood. Very limited evidence exists on patients who experience an atypical disease course. The aim of this study was to describe a cohort of children diagnosed with recurrent or persisting IgAV to identify any themes associated with their disease course and areas of unmet needs.

METHODS

A single centre retrospective study of children diagnosed with recurrent or persisting IgAV at Alder Hey Children's Hospital (Liverpool, UK). Clinical data, including features at presentation and during follow up, potential triggers, abnormal laboratory and histology results, treatment and outcome at last clinical review were retrospectively collected. Key themes were identified.

RESULTS

A total of 13 children met the inclusion criteria (recurrent disease, n = 4; persisting disease, n = 9). Median age at first presentation was 10.2 years [2.6-15.5], female:male ratio 1.2:1. Children in the atypical cohort were significantly older than a larger cohort of children who followed a non-complicated disease course (median age 5.5 years (range [0.6-16.7], p = 0.003)). All children re-presented with a purpuric rash (either recurring or persisting), accompanied by joint involvement in 92% of patients (12/13). Disease-modifying anti-rheumatic drugs (DMARDs) were used in 8/13 (62%) children. The median time from first presentation to diagnosis of atypical disease was 18.4 months [5.3-150.8] and the time from first presentation to treatment was 24.1 months [1.8-95.4]. Use of corticosteroids was significantly higher in children with renal involvement (p = 0.026). During follow up, 8/13 (62%) children were admitted at least once, whilst 10/13 (77%) had re-presented at least once to the emergency department. Five (38%) children were referred to psychology services and 7 (54%) children reported feelings of frustration.

CONCLUSIONS

This series describes some characteristics of a small cohort of children with atypical IgAV. It also identifies unmet needs in children with atypical IgAV, which includes delays in diagnosis and lengthy waits for treatment, lack of high-quality evidence regarding treatment choices and a high unrecognised disease burden. Further research is needed to study this subgroup of children as evidence is lacking.

Reporting the clinical spectrum of children with IgAV in a retrospective 24-year cohort: Influences of age and sex on clinical presentation

Background/aim

Immunoglobulin A vasculitis (IgAV) is one of the most common types of vasculitis in children. The aims of this study were to investigate the clinical characteristics of the disease, and the effects of age and sex on the clinical course in children with IgAV.

Materials and methods

This was a retrospective study including pediatric patients diagnosed with IgAV who attended follow-ups at the pediatric rheumatology department of a tertiary healthcare institution between January 1997 and December 2020. The patients were grouped and compared according to sex and age at diagnosis (<7 years vs. ≥7 years).

Results

The study included 709 children with IgAV, 392 (55.3%) of whom were male. The mean age at diagnosis was 7.9 ± 3.2 years. The most common disease onset season was autumn (31.2%). Upper respiratory infections (27.8%) were the most common predisposing factors. Gastrointestinal system (GIS), joint, and renal involvement were observed in 52.8%, 47.5%, and 17.5% of patients, respectively. Renal involvement, GIS involvement, and disease relapse were significantly more common among those diagnosed after 7 years of age compared to those diagnosed before the age of 7 (p < 0.001, p = 0.033, and p < 0.001, respectively). Scrotal involvement and subcutaneous edema were more common among those diagnosed at younger than 7 years compared to those aged ≥7 years at diagnosis (p < 0.001 and p = 0.016, respectively). GIS involvement was more frequently seen in males compared to females (p = 0.046).

Conclusion

It was demonstrated that being ≥7 years of age at diagnosis or being a male were associated with higher likelihood of renal and GIS involvement in children with IgAV.

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.

Proteome analysis reveals novel serum biomarkers for Henoch-Schönlein purpura in Chinese children

PURPOSE

Henoch-Schönlein purpura (HSP) is diagnosed based on characteristic skin changes. This study aimed to identify the serum biomarkers of HSP in children.

EXPERIMENTAL DESIGN

We performed proteomic analysis of serum samples from 38 paired pre- and posttherapy HSP patients and 22 healthy controls using a combination of magnetic bead-based weak cation exchange and MALDI-TOF MS. ClinProTools was used to screen the differential peaks. Then, LC-ESI-MS/MS was performed to identify the proteins. ELISA was used to verify the expression of whole protein in the serum of 92 HSP patients, 14 peptic ulcer disease (PUD) patients and 38 healthy controls, which were prospectively collected. Finally, logistic regression analysis was performed to analyze the diagnostic value of the above predictors and existing clinical indicators.

RESULTS

Seven potential HSP serum biomarker peaks (m/z:1228.95, m/z:1781.22, m/z:1468.43, m/z:1619.53, m/z:1868.41, m/z:1694.05, m/z:1743.25) with higher expression in the pretherapy group and one peak (m/z:1947.41) with lower expression in the pretherapy group were all identified as peptide regions of albumin (ALB), complement C4-A precursor (C4A), tubulin beta chain (TUBB), isoform 1 of fibrinogen alpha chain (FGA), and ezrin (EZR). The expression of identified proteins was validated by ELISA. Multivariate logistic regression analysis showed that serum C4A EZR and ALB were independent risk factors for HSP, serum C4A and lgA were independent risk factors for HSPN, and serum D-dimer was an independent risk factor for abdominal HSP.

CONCLUSIONS AND CLINICAL RELEVANCE

These findings revealed the specific etiology of HSP from the perspective of serum proteomics. The identified proteins might serve as potential biomarkers for HSP and HSPN diagnoses.

SIGNIFICANCE

Henoch-Schönlein purpura (HSP) is the most common systemic vasculitis in children, and its diagnosis depends primarily on characteristic skin changes. Early diagnosis of non-rash patients is difficult, especially for abdominal and renal types (Henoch-Schönlein purpura nephritis, HSPN). HSPN has poor outcomes, is diagnosed based on urinary protein and/or haematuria, and cannot be detected early in HSP. Patients with an earlier diagnosis of HSPN appear to have better renal outcomes. Our plasma proteomic analysis of HSP in children revealed that HSP patients could be distinguished from healthy controls and peptic ulcer disease patients using complement C4-A precursor (C4A), ezrin, and albumin. C4A and IgA could distinguish HSPN from HSP in the early stages, and D-dimer was a sensitive index used to distinguish abdominal HSP; identifying these biomarkers could promote the early diagnosis of HSP, especially pediatric HSPN and abdominal HSP, thereby improving precision therapy.

Association of Pediatric Vasculitis Activity Score with immunoglobulin A vasculitis with nephritis

BACKGROUND

Immunoglobulin A vasculitis with nephritis (IgAVN) is the most serious complication affecting long-term prognosis. Understanding the risk factors and markers for the development of IgAVN is essential. The aim of this study is to identify IgAVN-associated factors and to evaluate the usability of Pediatric Vasculitis Activity Score (PVAS) at diagnosis as an early marker for the development of IgAVN.

METHODS

We conducted a retrospective case-control study of 314 patients divided into two groups: those with nephritis (IgAVN) and without nephritis (non-IgAVN). The groups were compared in terms of clinical symptoms, laboratory values, and PVAS values.

RESULTS

In total, 18.5% of the patients had IgAVN; they were older than the non-IgAVN patients (median age was 8.8, p < 0.05). Arthritis/arthralgia, abdominal pain, and intestinal bleeding were more common, systolic and diastolic BP were higher in IgAVN (p < 0.05). CRP, serum creatinine, and urine protein/Cr, PVAS were higher, while serum albumin was lower in IgAVN (p < 0.05). The receiver operator characteristic curve (ROC) analysis showed that IgAV patients with a determined cut-off PVAS value greater than 3 had 70.7% sensitivity in predicting whether or not they would develop IgAVN. Logistic regression analysis found that PVAS > 3 and low serum albumin at the time of diagnosis were independent risk factors for IgAVN.

CONCLUSION

Our study revealed that PVAS > 3 at diagnosis is an independent predictor of IgAVN. Patients with PVAS > 3 should be followed more closely to ensure early diagnosis and management of IgAVN. A higher resolution version of the Graphical abstract is available as Supplementary information.

Preadolescent-versus adolescent-onset immunoglobulin A vasculitis: The impact of age on prognosis

BACKGROUND

This study aimed to investigate the characteristics of patients with preadolescent- and adolescent-onset immunoglobulin A vasculitis (IgAV) and to determine whether age affects IgAV outcomes in adolescents.

METHODS

Demographic, clinical, and laboratory data of 333 patients diagnosed with IgAV at the Department of Pediatric Rheumatology, University of Health Sciences, Ankara City Hospital, were evaluated retrospectively. The patients were classified into two groups: preadolescents (<10 years) and adolescents (10-19 years). Subgroup analyses were also performed by grouping the adolescent patients into early, middle, and late adolescent groups.

RESULTS

Of the 333 patients, 219 (65.8%) and 114 (34.2%) were preadolescents and adolescents. Palpable purpura, renal, joint, and gastrointestinal (GI) tract involvement were detected in 333 (100%), 78 (23.4%), 79 (23.7%), and 124 (37.2%) patients, respectively; testicular involvement was observed in 25 (13.3%) of 187 male patients. The frequency of renal involvement was significantly higher in the adolescent group than in the preadolescent group at the time of diagnosis (p = 0.030). Notably, joint involvement was significantly higher in the adolescent group (p = 0.001). The need for aggressive therapy was significantly higher in the adolescent group than in the preadolescent group (p = 0.003). There was no significant difference in clinical data, demographic characteristics, and laboratory findings between the adolescent subgroups (p > 0.05).

CONCLUSIONS

Immunoglobulin A vasculitis can occur at any age but the disease prognosis appears to worsen with age. The present study reported that joint involvement, kidney involvement, and the need for more aggressive treatment were higher in the adolescent group than in the preadolescent group.

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.

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.

Increased Urinary IgA in Paediatric IgA Vasculitis Nephritis

IgA vasculitis (IgAV) is the most common form of paediatric vasculitis, with up to 50% of patients experiencing kidney inflammation. Much remains unknown about IgAV, but it is believed to arise due to galactose-deficient IgA1 promoting an auto-inflammatory response. This study assesses whether urinary IgA can be detected in children with IgAV to allow further evaluation of IgA1 and whether it has any relationship with nephritis. Urinary and serum IgA concentrations were measured using commercially available ELISA kits. Patients were grouped into IgAV nephritis (IgAVN) or IgAV without nephritis (IgAVwoN). Fifty-nine children were included: IgAVN n = 12, IgAVwoN n = 35, and healthy controls (HC) n = 12, with a mean age of 8.2 ± 4.1 years. Urinary IgA concentrations were statistically significantly higher in patients with IgAV (107.1 ± 136.3 μg/mmol) compared to HC (50.6 ± 26.3 μg/mmol; p = 0.027) and IgAVN (229.8 ± 226.3 μg/mmol) compared to both IgAVwoN (65.0 ± 37.8 μg/mmol; p = 0.002) and HC (p < 0.001). Urinary IgA concentrations were able to distinguish between renal status (AUC 0.838, 95%CI [0.704−0.973], p < 0.001) and did not correlate with proteinuria (r = 0.124; p = 0.407). Urinary IgA concentrations are increased in children with IgAVN, and it has the potential to act as a non-invasive biofluid to further evaluate nephritis in this disease.

Prediction of renal damage in children with IgA vasculitis based on machine learning

This article is objected to explore the value of machine learning algorithm in predicting the risk of renal damage in children with IgA vasculitis by constructing a predictive model and analyzing the related risk factors of IgA vasculitis Nephritis in children. Case data of 288 hospitalized children with IgA vasculitis from November 2018 to October 2021 were collected. The data included 42 indicators such as demographic characteristics, clinical symptoms and laboratory tests, etc. Univariate feature selection was used for feature extraction, and logistic regression, support vector machine (SVM), decision tree and random forest (RF) algorithms were used separately for classification prediction. Lastly, the performance of four algorithms is compared using accuracy rate, recall rate and AUC. The accuracy rate, recall rate and AUC of the established RF model were 0.83, 0.86 and 0.91 respectively, which were higher than 0.74, 0.80 and 0.89 of the logistic regression model; higher than 0.70, 0.80 and 0.89 of SVM model; higher than 0.74, 0.80 and 0.81 of the decision tree model. The top 10 important features provided by RF model are: Persistent purpura ≥4 weeks, Cr, Clinic time, ALB, WBC, TC, Relapse, TG, Recurrent purpura and EB-DNA. The model based on RF algorithm has better performance in the prediction of children with IgA vasculitis renal damage, indicated by better classification accuracy, better classification effect and better generalization performance.

Association between common laboratory indices and IgAV recurrence in children

Background

IgA vasculitis (IgAV) is a common type of vasculitis seen in children. IgAV recurrence can result in chronic kidney disease. We aimed to explore the association between common laboratory indices and IgAV recurrence in children, and to establish a prediction model.

Methods

This retrospective study included children with diagnosed with IgAV hospitalized in Bazhong Central Hospital, Sichuan, from January 2014 to December 2019. Children were assigned to two groups based on IgAV recurrence, and baseline clinical data were collected for comparison. A logistic regression model to predict IgAV recurrence was established. The receiver operating characteristic curve was plotted. The area under the curve (AUC) was used to detect performance of the predictive model.

Results

This study included 193 children (39 [20.2%], recurrence group; 154 [79.8%], non-recurrence group). Based on multivariate regression analysis, the duration of illness and joint involvement were independent predictors of IgAV recurrence in children (P < 0.05). No significant differences were observed in common laboratory indices (P > 0.05). The AUC of the prediction model was 0.766 (P < 0.001) with sensitivity of 74.4% and specificity of 68.8%.

Conclusion

Common laboratory indices were not associated with recurrence of IgAV in children.

Development and validation of nomogram prediction model for severe kidney disease in children with Henoch–Schönlein purpura: A prospective analysis of two independent cohorts—forecast severe kidney disease outcome in 2,480 hospitalized Henoch–Schönlein purpura children

This study aimed to develop and validate a nomogram to forecast severe kidney disease (SKD) outcomes for hospitalized Henoch–Schönlein purpura (HSP) children. The predictive model was built based on a primary cohort that included 2,019 patients with HSP who were diagnosed between January 2009 and December 2013. Another cohort consisting of 461 patients between January 2014 and December 2016 was recruited for independent validation. Patients were followed up for 24 months in development/training and validation cohorts. The data were gathered at multiple time points after HSP (at 3, 6, 12, and 24 months) covering severe kidney disease as the severe outcome after HSP. The least absolute shrinkage and selection operator (LASSO) regression model was utilized to decrease data dimension and choose potentially relevant features, which included socioeconomic factors, clinical features, and treatments. Multivariate Cox proportional hazards analysis was employed to establish a novel nomogram. The performance of the nomogram was assessed on the aspects of its calibration, discrimination, and clinical usefulness. The nomogram comprised serious skin rash or digestive tract purpura, severe gastrointestinal (GI) manifestations, recurrent symptoms, and renal involvement as predictors of SKD, providing favorable calibration and discrimination in the training dataset with a C-index of 0.751 (95% CI, 0.734–0.769). Furthermore, it demonstrated receivable discrimination in the validation cohort, with a C-index of 0.714 (95% CI, 0.678–0.750). With the use of decision curve analysis, the nomogram was proven to be clinically useful. The nomogram independently predicted SKD in HSP and displayed favorable discrimination and calibration values. It could be convenient to promote the individualized prediction of SKD in patients with HSP.

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.

Individualized medication based on pharmacogenomics and treatment progress in children with IgAV nephritis

Immunoglobulin A vasculitis (IgAV) nephritis, also known as Henoch-Schönlein purpura nephritis (HSPN), is a condition in which small blood vessel inflammation and perivascular IgA deposition in the kidney caused by neutrophil activation, which more often leads to chronic kidney disease and accounts for 1%–2% of children with end-stage renal disease (ESRD). The treatment principles recommended by the current management guidelines include general drug treatment, support measures and prevention of sequelae, among which the therapeutic drugs include corticosteroids, immunosuppressive agents and angiotensin system inhibitors. However, the concentration range of immunosuppressive therapy is narrow and the individualized difference is large, and the use of corticosteroids does not seem to improve the persistent nephropathy and prognosis of children with IgAV. Therefore, individualized maintenance treatment of the disease and stable renal prognosis are still difficult problems. Genetic information helps to predict drug response in advance. It has been proved that most gene polymorphisms of cytochrome oxidase P450 and drug transporter can affect drug efficacy and adverse reactions (ADR). Drug therapy based on genetics and pharmacogenomics is beneficial to providing safer and more effective treatment for children. Based on the pathogenesis of IgAV, this paper summarizes the current therapeutic drugs, explores potential therapeutic drugs, and focuses on the therapeutic significance of corticosteroids and immunosuppressants in children with IgAV nephritis at the level of pharmacogenomics. In addition, the individualized application of corticosteroids and immunosuppressants in children with different genotypes was analyzed, in order to provide a more comprehensive reference for the individualized treatment of IgAV nephritis in children.

Development and Validation of a Differential Diagnosis Model for Acute Appendicitis and Henoch-Schonlein Purpura in Children

Objective: To study and develop a predictive model for the differential diagnosis of acute appendicitis (AA) and Henoch-Schonlein purpura (HSP) in children and to validate the model internally and externally. Methods: The complete data of AA and HSP cases were retrospectively analyzed and divided into internal and external verification groups. SPSS software was used for single-factor analysis and screening of independent variables, and R software was used for the development and verification of the diagnostic model. Lasso regression analysis was used to screen predictors and Lasso-logistic regression model was constructed, and K-fold cross-validation was used for the internal verification. In addition, nonfever patients were selected for model development and validation in the same way. Receiver operating characteristic (ROC) curves and calibration curves were drawn, respectively, to evaluate the 2 models. Results: Internal development and validation of the model showed that fever, neutrophil ratio (NEUT%), albumin (ALB), direct bilirubin (DBIL), C-reactive protein (CRP), and K were predictive factors for the diagnosis of HSP. The model was presented in the form of a nomogram, and the area under ROC curve of the development group and verification group was 0.9462 (95% confidence interval [CI] = 0.9402-0.9522) and 0.8931 (95% CI = 0.8724-0.9139), respectively. In the model of patients without fever, NEUT%, platelets (PLT), ALB, DBIL, alkaline phosphatase (ALP), CRP, and K were predictive factors for the diagnosis of HSP, and the area under ROC curve of the development group and verification group was 0.9186 (95% CI = 0.908-0.9293) and 0.8591 (95% CI = 0.8284-0.8897), respectively. Conclusion: In this study, 2 diagnostic models were constructed for fever or not, both of which had good discrimination and calibration, and were helpful to distinguish AA and HSP in children.

Serum immunoglobulin profiles in Chinese children with Henoch-Schönlein purpura

OBJECTIVE

The present study focuses on the associations of serum immunoglobulin with disease activity, relapse/recurrence and renal involvement in Henoch-Schönlein purpura (HSP) children.

METHODS

1683 Chinese children with HSP were recruited from January 2015 to January 2021. Laboratory data of blood samples and urine tests were collected. Renal biopsy was performed by the percutaneous technique. Patients' histories associated with HSP onset were obtained by interviews and questionnaires.

RESULTS

(1) IgA and IgE were dramatically elevated in HSP patients as compared with their normal values, and subject to a 1.75-3.09 fold and a 1.97-2.61 fold increase, respectively. (2) No significant correlation of the disease activity with IgA and IgE was determined, respectively. (3) The serum IgA levels were significantly lower in patients with relapse/recurrence than that in patients without relapse/recurrence, which may be attributed to the transmission of IgA-mediated immune complexes from blood to vessel walls. (4) No significant correlation was found between serum IgA, IgE levels and the pathological classification.

CONCLUSIONS

HSP children have marked disorders of serum immunoglobulin profiles, characterized by significant increases in IgA and IgE. The detection of serum IgA may be applicable to predict relapse/recurrence of HSP, whereas not associated with disease activity and renal involvement.

Urinary Protein Array Analysis to Identify Key Inflammatory Markers in Children with IgA Vasculitis Nephritis

Chronic kidney disease is a recognised complication of immunoglobulin A vasculitis, (IgAV; formerly Henoch–Schonlein purpura—HSP). The pathophysiology of IgAV and why some patients develop significant renal involvement remains largely unknown. Identifying urinary inflammatory markers could direct targets for earlier intervention. The aim of this cross-sectional exploratory study was to perform a large protein array analysis to identify urinary markers to provide insight into the mechanisms of kidney inflammation in children with established IgAV nephritis (IgAVN). Determination of the relative levels of 124 key proteins was performed using commercially available proteome profiler array kits. Twelve children were recruited: IgAVN, n = 4; IgAV without nephritis (IgAVwoN), n = 4; healthy controls (HCs), n = 4. The urinary concentrations of twenty proteins were significantly different in IgAVN compared to IgAVwoN. The largest fold changes were reported for B-cell activating factor (BAFF), Cripto-1, sex-hormone-binding globulin and angiotensinogen. The urinary levels of complement components C5/C5a and factor D were also significantly elevated in patients with IgAVN. A total of 69 urinary proteins significantly raised levels in comparisons made between IgAVN vs. HCs and nine proteins in IgAVwoN vs. HCs, respectively. This study identified key urinary proteins potentially involved in IgAVN providing new insight into the pathophysiology. Further longitudinal studies with larger cohorts are needed to quantitatively analyse these biomarkers.

Clinical spectrum of immunoglobulin A vasculitis in children and determining the best timing of urine examination to predict renal involvement

BACKGROUND

Immunoglobulin A (IgA) vasculitis (also known as Henoch-Schonlein purpura) is the most common small vessel vasculitis of childhood. The long-term prognosis depends on renal involvement. The aim of this study was to evaluate the risk factors associated with renal involvement in children with IgA vasculitis and to investigate the best timing of urine examination to predict the presence of renal involvement at the sixth month after the diagnosis.

METHODS

In this prospective observational study, medical records, demographic data, clinical findings, laboratory tests, and urine microscopic examinations of pediatric patients diagnosed with IgA vasculitis were evaluated to identify potential risk factors associated with renal involvement.

RESULTS

A total of 178 patients with a median age of 6 years were involved in the study. Renal involvement was found in 24 (13.5%) patients. Most of the patients (85.7%), whose urine examination was found to be abnormal at the sixth month after the diagnosis, also had abnormalities in the first month urine examination. Factors significantly associated with renal involvement were as follows: older age, presence of hematuria and or proteinuria in the first month urine examination and patients who presented the disease in the spring season. Multivariate logistic regression analysis showed age ≥8 years (p = 0.005), the season of onset (p = 0.025), serum creatinine levels (p = 0.016), and abnormal urine examinations at the first-month visits (p = 0.005) significantly increased the risk of renal involvement.

CONCLUSION

This study has demonstrated that the optimal date to predict the presence of hematuria and/or proteinuria in the sixth month is the urine examination performed in the first month of the disease. Therefore, we think that patients with IgA vasculitis who show a presence of hematuria and/or proteinuria in the first-month urine examination should be followed more closely.

Activation of Complement System in Henoch-Schönlein Purpura Nephritis

Introduction: We studied the association between Henoch-Schönlein purpura nephritis (HSPN) and complement system activation. Methods: We retrospectively reviewed the pathologic findings and medical records of 35 children and 12 adults with HSPN and compared the differences according to C4d positivity in three groups consisting of total 47 patients, 35 pediatric and 12 adult patients, respectively. C4d staining of renal biopsy was additionally performed at the time of diagnosis or retrospectively using archival biopsy material. Results: The overall rate of C4d positivity was 53.2%: 20 (57.1%) of the 35 children and five (41.7%) of the 12 adults. Among the groups there was no significant difference in the severity of proteinuria, renal function, presence of crescents or mesangial proliferation stratified by C4d positivity, unlike IgA nephropathy. Conclusions: We suggest that the activation of complement system is not correlated with the clinical or pathological severity of HSPN.

Risk assessment and prediction model of renal damage in childhood immunoglobulin A vasculitis

OBJECTIVES

To explore the risk factors for renal damage in childhood immunoglobulin A vasculitis (IgAV) within 6 months and construct a clinical model for individual risk prediction.

METHODS

We retrospectively analyzed the clinical data of 1,007 children in our hospital and 287 children in other hospitals who were diagnosed with IgAV. Approximately 70% of the cases in our hospital were randomly selected using statistical product service soltions (SPSS) software for modeling. The remaining 30% of the cases were selected for internal verification, and the other hospital's cases were reviewed for external verification. A clinical prediction model for renal damage in children with IgAV was constructed by analyzing the modeling data through single-factor and multiple-factor logistic regression analyses. Then, we assessed and verified the degree of discrimination, calibration and clinical usefulness of the model. Finally, the prediction model was rendered in the form of a nomogram.

RESULTS

Age, persistent cutaneous purpura, erythrocyte distribution width, complement C₃, immunoglobulin G and triglycerides were independent influencing factors of renal damage in IgAV. Based on these factors, the area under the curve (AUC) for the prediction model was 0.772; the calibration curve did not significantly deviate from the ideal curve; and the clinical decision curve was higher than two extreme lines when the prediction probability was ~15-82%. When the internal and external verification datasets were applied to the prediction model, the AUC was 0.729 and 0.750, respectively, and the Z test was compared with the modeling AUC, P > 0.05. The calibration curves fluctuated around the ideal curve, and the clinical decision curve was higher than two extreme lines when the prediction probability was 25~84% and 14~73%, respectively.

CONCLUSION

The prediction model has a good degree of discrimination, calibration and clinical usefulness. Either the internal or external verification has better clinical efficacy, indicating that the model has repeatability and portability.

CLINICAL TRIAL REGISTRATION

www.chictr.org.cn, identifier ChiCTR2000033435.

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.

A retrospective study on the characteristics of renal pathological grades in HSPN children with mild to moderate proteinuria

OBJECTIVE

To investigate the characteristics of renal pathological grades in Henoch-Schönlein purpura nephritis (HSPN) children with mild to moderate proteinuria and the correlation between pathological grade and severity of proteinuria among this population.

METHODS

HSPN children who were presented with mild (150 mg <24 h urinary protein <25 mg/kg) to moderate (25 mg/kg ≤24 h urinary protein <50 mg/kg) proteinuria and performed renal biopsy without steroid ± immunosuppressant treatment in the Second Xiangya Hospital between January 2010 and March 2021 were involved. We retrospectively analyzed the correlation between age, disease course, degree of proteinuria, type of immunoglobulin deposits, C3 deposits in glomeruli and renal pathological grade.

RESULTS

(1) 72 HSPN children including 46 boys and 26 girls were included, with a mean age of onset of 9.01 ± 2.65 years old. The majority of these patients (62.5%) had a disease course between 1 week to 1 month. 51 patients presented with mild proteinuria and 21 patients with moderate proteinuria. (2) Renal biopsy results showed that ISKDC Grade IIIa were both predominant in mild proteinuria group (25, 49%) and moderate proteinuria group (11, 52.4%). 32 patients had grade II (44.4%), 2 had grade IIIb (2.8%), 1 had grade IV (1.4%), and 1 had grade VI (1.4%). There was no correlation between age, disease course and renal pathological grade (p > 0.05). (3) In patients with mild proteinuria (n = 51), 27 (52.9%) HSPN children had a pathological grade ≥ grade III. In patients with moderate proteinuria (n = 21), 13 (61.9%) HSPN children had grade ≥ III. There was no significant difference in the proportion of renal pathological grade between the 2 groups (p > 0.05). (4) There was no significant correlation between glomerular C3 deposits or immunoglobulin deposit types and renal pathological grade (p = 0.776 and p = 0.056 respectively).

CONCLUSION

In HSPN children with mild to moderate proteinuria, longer disease course or heavier urinary protein level is not completely parallel with higher renal pathological grade. ISKDC grade IIIa is the most common pathological grade. Clinicians should pay great attention to the renal injury in patients with mild to moderate proteinuria.

Epidemiological and clinical aspects of immunoglobulin A vasculitis in childhood: a retrospective cohort study

Background

A retrospective study was conducted in order to investigate and describe the characteristics of Immunoglobulin A vasculitis (IgAV), previously known as Henoch-Schӧnlein purpura, in the paediatric population of a community-based healthcare delivery system in the Italian region of Abruzzo.

Methods

This is a population-based retrospective chart review of the diagnosis of IgAV in children ages 0 to 18, admitted to the Department of Paediatrics of Chieti and Pescara between 1 January 2000 and 31 December 2016. All children enrolled presented with clinical symptoms and laboratory findings and met the EULAR/PRINTO/PRES 2008 criteria.

Results

Two-hundred-eight children met the criteria for IgAV, with the highest incidence reported among children below 7-years of age. A correlation with recent infections was found in 64% of the cohort; the onset was more frequently during the winter and fall. Purpura had a diffuse distribution in the majority of patients; joint impairment was the second most frequent symptom (43%), whereas the gastrointestinal tract was involved in 28% of patients.

Conclusions

Hereby, we confirm the relative benignity of IgAV in a cohort of Italian children; with regards to renal involvement, we report a better outcome compared to other studies. However, despite the low rate of renal disease, we observed a wide use of corticosteroids, especially for the treatment of persistent purpura.

Clinico-Epidemiological Profile and Outcome of Children with IgA Vasculitis in Aseer Region, Southwestern Saudi Arabia

Introduction: Immunoglobulin A (IgA) vasculitis is one of the most common forms of primary vasculitis in children; it typically has a benign course but can be aggressive and require intervention. Aim of the work: The aim of this retrospective study was to evaluate the epidemiological and clinical profile and treatment modalities used for children with IgA vasculitis in the southwestern region of Saudi Arabia. Material and Methods: We reviewed the medical records of 89 children admitted to Abha Maternity and Children Hospital in the southwestern region of Saudi Arabia from January 2016 to December 2020 with a confirmed diagnosis of IgA vasculitis according to the European League Against Rheumatism/Paediatric Rheumatology International Trials Organisation/Pediatric Rheumatology European Society criteria. Results: Eighty-nine children had a confirmed diagnosis of IgA vasculitis, with 50 boys (56.2%) and 39 girls (43.8%; male-to-female ratio of 1.28:1) and a mean age at diagnosis of 5.87 ± 2.81 years. The mean hospital stay duration was 5.66 ± 4.72 days. Infections preceded 29.2% of the cases, with upper respiratory tract infections comprising 24.7%. Approximately 31.5% of the cases were diagnosed in summer, followed by autumn in 28% of the cases. Rash was present in 100%, arthritis in 72.2%, gastrointestinal tract involvement in 60.7%, and renal involvement in 23.5% of cases. Thrombocytosis and leukocytosis were found in 35% and 46% of all cases, and 52.3% and 47.6.25% of cases with renal involvement, respectively (OR = 2.035, 95% CI: 0.75-5.52 and OR = 1.393, 95% CI: 0.522-1.716, respectively). Approximately 26% of cases experienced relapses. Treatment was conservative in 23.6%, oral prednisolone in 23.6%, and pulse steroid in 45% of cases. Abdominal pain with lower gastrointestinal tract bleeding was the primary indication for initiating pulse steroid treatment. Conclusions: There were similarities and differences in the epidemiology and frequency of clinical manifestations of patients with IgA vasculitis compared to previous studies. Children presenting with such epidemiological and clinical profile need to be closely monitored and long-term follow-up is recommended to improve the outcomes.

Risk factors for renal involvement in Henoch-Schönlein purpura

OBJECTIVE

Henoch-Schönlein purpura is a systemic vasculitis that mainly occurs in children. Renal impairment is a major complication of Henoch-Schönlein purpura, but there is no established predictive marker for renal involvement. Thus, in this study, we investigated the risk factors for renal involvement in children with Henoch-Schönlein purpura.

METHOD

The medical records of children newly diagnosed as having Henoch-Schönlein purpura between 2005 and 2020 were reviewed retrospectively. Selected laboratory data were recorded before treatment initiation. The date and the age at diagnosis; sex; and the presence of arthralgia, gastrointestinal and renal involvement were obtained retrospectively.

RESULTS

This study included a total of 186 patients with Henoch-Schönlein purpura. Among them, 36.0% had renal involvement; 28.4% had only microscopic hematuria, 53.7% had non-nephrotic range proteinuria, and 17.9% had nephrotic-range proteinuria during follow-up. The mean age was higher (p = 0.016) and female sex was predominant (p = 0.001) in patients with renal involvement than in those without renal involvement. Blood neutrophil/lymphocyte ratio (p = 0.002) and platelet/lymphocyte ratio (p = 0.002) were significantly higher than that of the patients without renal involvement. No statistically significant differences were observed in the hemoglobin concentration, platelet count, presence of arthralgia, and gastrointestinal involvement between patients with and without renal involvement. Logistic regression analysis revealed female sex (odd ratio = 3.213) and neutrophil/lymphocyte ratio (odd ratio = 1.329) as risk factors for renal involvement.

CONCLUSIONS

Female sex and high neutrophil/lymphocyte ratio were risk factors for renal involvement in Henoch-Schönlein purpura.

Is complement the main accomplice in IgA nephropathy? From initial observations to potential complement-targeted therapies

IgA Nephropathy (IgAN) is the main cause of primary glomerulonephritis, globally. This disease is associated with a wide range of clinical presentations, variable prognosis and a spectrum of histological findings. More than fifty years after its first description, this heterogeneity continues to complicate efforts to understand the pathogenesis. Nevertheless, involvement of the complement system in IgAN was identified early on. Dysfunction of the immunoglobulin A (IgA) system, the principal offender in this disease, including modification of isoforms and glycoforms of IgA1, the nature of immune complexes and autoantibodies to galactose deficient IgA1 might all be responsible for complement activation in IgAN. However, the specific mechanisms engaging complement are still under examination. Research in this domain should allow for identification of patients that may benefit from complement-targeted therapy, in the foreseeable future.

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.

Gastrointestinal involvement and its association with the risk for nephritis in IgA vasculitis

Background:

We analysed clinical and biochemical parameters in predicting severe gastrointestinal (GI) manifestations in childhood IgA vasculitis (IgAV) and the risk of developing renal complications.

Methods:

A national multicentric retrospective study included children with IgAV reviewed in five Croatian University Centres for paediatric rheumatology in the period 2009–2019.

Results:

Out of 611 children, 281 (45.99%) had at least one GI manifestation, while 42 of 281 (14.95%) had the most severe GI manifestations. Using logistic regression several clinical risk factors for the severe GI manifestations were identified: generalized rash [odds ratio (OR) 2.09 (95% confidence interval (CI) 1.09–4.01)], rash extended on upper extremities (OR 2.77 (95% CI 1.43–5.34)] or face [OR 3.69 (95% CI 1.42–9.43)] and nephritis (IgAVN) [OR 4.35 (95% CI 2.23–8.50)], as well as lower values of prothrombin time (OR 0.05 (95% CI 0.01–0.62)], fibrinogen [OR 0.45 (95% CI 0.29–0.70)] and IgM [OR 0.10 (95% I 0.03–0.35)]] among the laboratory parameters. Patients with severe GI involvement more frequently had relapse of the disease [OR 2.14 (CI 1.04–4.39)] and recurrent rash [OR 2.61 (CI 1.27–5.38)]. Multivariate logistic regression found that the combination of age, GI symptoms at the beginning of IgAV and severity of GI symptoms were statistically significant predictors of IgAVN. Patients in whom IgAV has started with GI symptoms [OR 6.60 (95% CI 1.67–26.06)], older children [OR 1.22 (95% CI 1.02–1.46)] with severe GI form of IgAV (OR 5.90 (95% CI 1.12–31.15)] were particularly high-risk for developing IgAVN.

Conclusion:

We detected a group of older children with the onset of GI symptoms before other IgAV symptoms and severe GI form of the IgAV, with significantly higher risk for acute and chronic complications of IgAV.

Streptococcal infection in childhood Henoch-Schönlein purpura: a 5-year retrospective study from a single tertiary medical center in China, 2015-2019

BACKGROUND

The present study focuses on the associations of streptococcal infection with the clinical phenotypes, relapse/recurrence and renal involvement in Henoch-Schönlein purpura (HSP) children.

METHODS

Two thousand seventy-four Chinese children with HSP were recruited from January 2015 to December 2019. Patients' histories associated with HSP onset were obtained by interviews and questionnaires. Laboratory data of urine tests, blood sample and infectious agents were collected. Renal biopsy was performed by the percutaneous technique.

RESULTS

(1) Streptococcal infection was identified in 393 (18.9%) HSP patients, and served as the most frequent infectious trigger. (2) Among the 393 cases with streptococcal infection, 43.0% of them had arthritis/arthralgia, 32.1% had abdominal pain and 29.3% had renal involvement. (3) 26.1% of HSP patients relapsed or recurred more than 1 time within a 5-year observational period, and the relapse/recurrence rate in streptococcal infectious group was subjected to a 0.4-fold decrease as compared with the non-infectious group. (4) No significant differences in renal pathological damage were identified among the streptococcal infectious group, the other infectious group and the non-infectious group.

CONCLUSIONS

Streptococcal infection is the most frequent trigger for childhood HSP and does not aggravate renal pathological damage; the possible elimination of streptococcal infection helps relieve the relapse/recurrence of HSP.

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.

Clinical spectrum and outcome of immunoglobulin A vasculitis in children: A 10-year clinical study

BACKGROUND

Immunoglobulin A (IgA) vasculitis is the most common vasculitides of childhood. The aim of this study was to characterise the disease and identify clinical and laboratory factors associated with renal involvement.

METHODS

Medical records of children aged ≤18 years with the diagnosis of IgA vasculitis according to the EULAR/PRES criteria were retrospectively reviewed for demographic data, clinical manifestations and laboratory tests. Factors associated with renal involvement were determined using multivariable logistic regression analysis.

RESULTS

A total of 113 patients were involved in the study. There were 57.5% of males (male: female ratio of 1.4:1). The mean (SD) age was 7.1 (3.0) years. Most of the patients presented during the fall (37.2%) and winter (29.2%). The most common presenting complaints were skin rash (83.2%) and arthralgia (9.7%). The most frequent presentation of the skin was palpable purpuric rash, except for two patients (1.8%) presenting with blistering eruptions in the form of hemorrhagic bullae and ecchymoses of both extremities. We have encountered one patient with pulmonary-renal syndrome. Renal involvement was found in 27.4% of the patients. In the multivariate analysis, the strongest factors associated with renal involvement were older age and elevated creatinine level. Factors that improved model fit were higher platelet and lower white blood cell counts, elevated anti-streptolysin O and a history of preceding infection.

CONCLUSION

The clinical profile of the disease in our cohort was similar to other reports. However, we have encountered a few severe and rare atypical presentations. Over a quarter of children in our setting had renal involvement. Children presenting with these risk factors need to be closely monitored and long-term follow-up is recommended.