Abstract: SA-PO256

Outcome Predictors in Childhood-Onset Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis: Clinicopathological Analysis in a Nationwide Japanese Survey

Session Information

Category: Glomerular

  • 1005 Clinical Glomerular Disorders

Authors

  • Hirano, Daishi, The Jikei university school of medicine, Tokyo, Japan
  • Iijima, Kazumoto, Dept. of Pediatrics, Kobe Univ. Graduate School of Medicine, Kobe, Japan
  • Ito, Shuichi, Department of Pediatrics, Graduate School of Medicine, Yokohama City University, Yokohama, Japan
Background

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) occurs mainly in adults (estimated annual incidence ∼ 10–20 per million, peak age at onset 60 years). Little is known about the disease in children. Here, we examined clinicopathological predictors of patient and renal outcomes in childhood-onset AAV.

Methods

This was a retrospective nationwide multicenter survey of patients with AAV diagnosed before age 16. Eligibility criteria were: (1) fulfilled the Chapel Hill Consensus Conference criteria for microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA), and (2) kidney biopsy showing histology consistent with AAV.

Results

The cohort consisted of 46 children; 35 (76%) were female, 38 (83%) had MPA, 9 (17%) had GPA, 83% were MPO-ANCA-positive, 13% were PR3-ANCA-positive. Median age at onset was 10.7 years, and median time to diagnosis was 2.0 months. Initial symptoms included fever and fatigue (43%), renal (74%), pulmonary (30%), ocular (20%), and mucocutaneous involvement (22%). Clinical features differed between MPA and GPA. Remission was achieved after induction therapy in 27 (55%) cases. After a median follow-up of 3.6 years, 14 (30%) patients had chronic kidney disease stages 2–3. Seven (15%) patients progressed to end-stage renal disease (ESRD). Renal outcome was better in GPA than MPA. In univariate analysis, although sex, age at onset, and diagnosis delay were not associated with risk of progression to ESRD, type of AAV, nephrotic-range proteinuria, and histological chronicity indices predicted renal outcome. Nephrotic-range proteinuria was significantly correlated with histological chronicity (r = 0.50, P〈 0.01) and was an independent predictor of ESRD on logistic regression ( P〈 0.01).

Conclusion

There were significant differences between two types of AAV in terms of clinical features and outcomes. Nephrotic-range proteinuria was an independent predictor of ESRD. Nearly 90% of the cohort did not need renal replacement therapy at a median follow-up of 3.6 years, indicating that renal survival in childhood-onset AAV has improved with the development of modern therapies.

Funding

  • Government Support - Non-U.S.