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

Epidemiology and Clinical Characteristics of Henoch-Schönlein Purpura Associated with Streptococcal Infection in 217 Children in Hubei Province, China

Objectives The objectives of present study were to analyze the association of the streptococcal infection with childhood Henoch-Schönlein purpura (HSP) in China. Methods: We performed a case-control study over a period of five years to evaluate the epidemiology and clinical characteristics of group A β-hemolytic streptococcal (GABHS) triggered HSP. Results: 1. The frequency of GABHS-triggered HSP was 15.1%, while that of GABHS infection developing HSP in children was 4.7%. 2.The epidemiological characteristics of HSP with streptococcal infection were similar to those of HSP alone. 3. The GABHS-triggered HSP cases had a significantly higher frequency of renal involvement than the noninfectious group. 4. IgA and IgG were significantly increased in the streptococcal infection group than in the noninfectious group, while the levels of C3 and C4 decreased significantly. Conclusions: GABHS infection is the most frequent agent in HSP children, and may aggravate the immune dysfunction and prolong the course of HSP.

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.

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.

Epidemiology and Clinical Characteristics of Henoch-Schönlein Purpura Associated with Epstein-Barr Virus Infection

Background

Henoch-Schönlein purpura (HSP) is an immune-mediated vasculitis, and the formation of immune complexes may be triggered by exposure to Epstein-Barr virus (EBV) infection.

Methods

We performed a five-year case-control study to evaluate the epidemiology and clinical characteristics of HSP associated with EBV infection.

Results

The incidence of EBV-triggered HSP was 4.2%, while EBV infection in children with HSP was 0.9%; The EBV-triggered HSP cases had a significantly higher frequency of abdominal pain than the Mycoplasma Pneumoniae (MP)-triggered HSP group (χ2 = 8.024, p = 0.005); Significant differences were observed in the duration of abdominal pain (Z = -1.935, p = 0.027) between the two groups; C3 (t = 9.709, p < 0.001), IgA (t = 20.39, p < 0.001) and IgG (t = 6.407, p < 0.001) were significantly increased in the EBV infection group than those in the healthy control group. Notably, significantly higher proportion of CD19 (t = 6.773, p < 0.001) and lower proportion of CD56 (t = 11.13, p < 0.001) was found in EBV infection group compared with healthy control group. The IgA level was higher than that of the non-infectious group (t = 2.162, p = 0.032), but their CD4/CD8 ratio (t = 10.070, p < 0.001) and CD56 proportion (t = 2.096, p = 0.037) were significantly lower.

Conclusions

Both cellular and humoral immunity were involved in the pathogenesis of EBV-triggered HSP, leading to increased production of inflammatory mediators and immunoglobulins. Those events may cause or promote the development of systemic vessel vasculitis.