Background and objective: IgA vasculitis (IgAV) is the most common childhood vasculitis, characterized by palpable purpura, abdominal pain, arthritis, and kidney involvement. Whereas other organ conditions are mostly benign and self-limiting, nephritis may lead to end-stage renal disease. The aim of this study was to evaluate risk factors associated with renal involvement and severe kidney disease in childhood IgAV.
Methods: A retrospective study was conducted in children and adolescents aged <18 years who were diagnosed with IgAV based on the EULAR/PRINTO/PRES 2010 criteria from January 2009 to December 2018. We reviewed demographic data, clinical manifestations, and laboratory data from medical records. Renal involvement was defined as hematuria and/or proteinuria. Severe renal involvement was defined by the presence of macroscopic hematuria, nephrotic syndrome, acute nephritis syndrome, and renal insufficiency. Logistic regression analysis was used to determine risk factors of renal involvement in patients with IgAV. We compared characteristics between patients with mild and severe renal involvement.
Result: A total of 95 patients with IgAV were enrolled in the study. There were 55 (57.9%) males, with a mean age at diagnosis of 8.9 ± 3.5 years. Renal involvement occurred in 41 patients (43.2%). Of those with renal involvement, 14 patients (34.1%) had severe renal manifestations. Patients with renal involvement had a significant greater number of hypertension, compared with those without renal involvement (24.4% vs. 1.9%; p 0.001). In regression analysis, the risk factors associated with renal involvement were age ≥7 years at diagnosis (OR 4.27, CI 1.18 to 15.41; p 0.027) and hypertension (OR 41.05, CI 2.12 to 796.60; p 0.014). In subgroup analysis, patients with severe renal involvement had significantly higher numbers of arthritis (57.1% vs. 11.1%; p 0.003), hypertension (50.0% vs. 11.1%; p 0.017), and obesity (30.8% vs. 4.0%; p 0.038), compared with those with mild renal involvement.
Conclusion: We found factors associated with IgAV nephritis; these included age ≥7 years at diagnosis and hypertension. Arthritis and obesity were risk factors for developing severe kidney disease.
Keywords: IgA vasculitis, renal involvement, nephritis, risk factors
