RESUMO
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.