Comprehensive analysis of the clinical and pathological features and prognoses of children with immunoglobulin A vasculitis nephritis with immunoglobulin M deposits in glomeruli.

BACKGROUND

The clinical significance of immunoglobulin M (IgM) deposition in the glomeruli of children with immunoglobulin A vasculitis (IgAV) nephritis remains unclear. This study aimed to analyze the clinical and pathological characteristics and prognoses of this population.

METHODS

Patients were divided into three groups according to histopathological IgM deposition intensity: grade A (204 cases); grade B (101 cases); and grade C + D (54 cases). The clinicopathological characteristics and follow-up information of the three groups of patients were collected and compared.

RESULTS

This study included 359 children with IgAV nephritis and found that 44.9% of them had IgM deposition in the kidney glomerulus. Children with IgM deposition and IgAV nephritis have relatively severe clinicopathological features. A total of 39 children (10.9%) had entered the end-stage kidney disease stage. Kaplan-Meier analysis showed that cumulative renal survival was significantly lower in children with higher glomerular IgM deposition (log-rank test chi-square = 55.341, p < 0.001). Multivariable Cox regression analysis found that IgM deposition (grade C + D: hazard ratio [HR], 2.04; 95% confidence interval [CI], 1.67-3.93; p = 0.04; grade B: HR, 2.59; 95% CI, 1.08-4.23; p = 0.03) and S1 (HR, 1.76; 95% CI, 0.42-2.98; p = 0.03) were independent risk factors for poor prognoses in children with IgAV nephritis. The receiver operating characteristic curve indicated that IgM deposition presented significant predictive capability.

CONCLUSION

There are differences in the clinicopathological features of IgAV nephritis with different degrees of mesangial IgM deposition. IgM deposition and S1 are independent risk factors for poor prognoses of IgAV nephritis in children.