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

Clinical characteristics and risk factors of cardiac involvement in pediatric immunoglobulin A vasculitis: A 7-year retrospective study from a single tertiary medical center

Immunoglobulin A vasculitis(IgAV) is the most common form of systemic vasculitis affecting children. To date, cardiac involvement in pediatric IgAV has not been fully investigated and its prevalence may be underestimated. This study aims to reveal the clinical and laboratory characteristics of cardiac involvement in pediatric IgAV and further determine its risk factors. A total of 1451 children with IgAV were recruited between January 2016 and December 2022. According to the severity of cardiac involvement, the patients were divided into the myocarditis/suspected myocarditis group, cardiac abnormalities group, and non-cardiac involvement group. Demographic, clinical, and laboratory characteristics were retrospectively extracted from the individual data collected in the medical records. Among the 1451 pediatric IgAV patients, 179 (12.3%) were identified with cardiac involvement, including 154 (10.6%) with cardiac abnormalities and 25 (1.7%) with myocarditis/suspected myocarditis. Cardiac involvement in pediatric IgAV mainly manifested as elevated cardiac biomarker levels (n = 162), electrocardiogram abnormalities (n = 46), and echocardiogram/chest X-ray abnormalities (n = 15); however, cardiac-related symptoms were only observed in 15.1% of patients with cardiac involvement. Multivariate analysis demonstrated that interval from disease onset to diagnosis > 7 days (OR, 2.157; 95% CI, 1.523-3.057; p < 0.001), IgAV with multi-organ involvement (OR, 1.806; 95% CI, 1.242-2.627; p = 0.002), and elevated D-dimer levels (OR, 1.939; 95% CI, 1.259-2.985; p < 0.001) were independent risk factors for cardiac involvement in pediatric IgAV. The length of hospital stay was significantly longer in the myocarditis/suspected myocarditis group compared with the other two groups (p < 0.05).     Conclusion: This study suggests that cardiac involvements in pediatric IgAV is non-negligible, and cardiac involvement is associated with interval from disease onset to diagnosis > 7 days, IgAV with multi-organ involvement, and elevated D-dimer levels. Severe cardiac involvement may affect the prognosis of pediatric IgAV. What is Known: • Immunoglobulin A vasculitis (IgAV) is the most common form of systemic vasculitis affecting children and adolescents, which exhibits diverse clinical manifestations. Cases of severe IgAV complicated by cardiac involvement have been anecdotally reported. What is New: • The present study suggests that cardiac involvements in pediatric IgAV is non-negligible, and cardiac involvement is associated with interval from disease onset to diagnosis > 7 days, IgAV with multi-organ involvement, and elevated D-dimer levels. Severe cardiac involvement may affect the prognosis of pediatric IgAV.

Regulatory T and B cells in pediatric Henoch-Schönlein purpura: friends or foes?

BACKGROUND AND OBJECTIVES

Henoch-Schönlein purpura (HSP) is the most common immunoglobulin A-mediated systemic vasculitis in childhood. We studied immune dysregulation in HSP by analyzing regulatory T (Treg), T helper 3 (Th3), and regulatory B cell (Breg) subpopulations that might intervene in immune activation, IgA production, and HSP clinical manifestations.

METHODS

This prospective study included 3 groups of children: 30 HSP on acute phase, 30 HSP on remission, and 40 healthy controls (HCs) matched on age. Treg, Breg, and Th3 were analyzed by flow cytometry. Serum immunoglobulin and cytokine levels were quantified by ELISA and Luminex.

RESULTS

Treg frequencies were higher in acute HSP than in remitting HSP and HCs (6.53% [4.24; 9.21] vs. 4.33% [3.6; 5.66], p = 0.002, and vs. 4.45% [3.01; 6.6], p = 0.003, respectively). Activated Th3 cells (FoxP3 + Th3 cells) tend to be more abundant in HSP than in HCs (78.43% [50.62; 80.84] vs. 43.30% [40.20; 49.32], p = 0.135). Serum IgA, IL-17, and latency-associated peptide (a marker of the anti-inflammatory cytokine TGF-beta production) were significantly and inflammatory cytokines TNF-alpha, IL-1-beta, and IL-6 were non-significantly higher in HSP than HCs. Bregs were identical between the groups, but, in patients with renal impairment, Breg percentage was lower compared to those without. Treg removal in PBMC culture resulted in an increase in IgA production in HSP proving a negative regulatory role of Tregs on IgA production.

CONCLUSIONS

In pediatric HSP, immune activation persists in spite of an increase in Th3 and Tregs. Th3 could be involved in IgA hyperproduction, inefficiently downregulated by Tregs. Lack of Bregs appears linked to renal impairment.