Renal survival and prognostic factors in patients with PR3-ANCA associated vasculitis with renal involvement

Abstract

Background: Severe renal disease is a feature of anti-neutrophil cytoplasmic antibodies (ANCA)-associated small-vessel vasculitis. We evaluated patient and renal survival and prognostic factors in patients with PR3-ANCA associated vasculitis with renal involvement at diagnosis during long-term follow-up.

Methods: Eighty-five patients were diagnosed between 1982 and 1996 and followed until 2001 allowing >or=5 years of follow-up. All patients were treated with prednisolone and cyclophosphamide. Univariate and multivariate analyses with patient and renal survival as dependent variables were performed.

Results: Of the 85 patients in this study, 17 (20%) died within one year after diagnosis. Of the 25 patients (29%) who were dialysis dependent at diagnosis, two remained dependent and two again became dialysis dependent after less than one year; nine died early without renal recovery. Risk factors for death occurring within one year in univariate analysis (RR, 95% CI) were age>65 years (6.5, 1.6-13.7) and dialysis dependency at diagnosis (3.6, 1.0-13). Twenty patients died beyond one year during the long-term follow-up. Male gender (4.7, 1.6-10) and developing dialysis dependency during follow-up (4.1, 1.4-12) were associated with poor outcome. Risk factor for renal failure within one year was dialysis dependency at diagnosis (29, 3.6-229). Of 64 patients dialysis independent one year after diagnosis, 12 patients became dialysis dependent during follow-up. A renal relapse was strongly associated with development of renal failure in long-term follow-up (17, 3.5-81).

Conclusions: Early death and failure to recover renal function in PR3-ANCA associated vasculitis is associated with age> 65 years and dialysis dependency at diagnosis. Long-term renal survival is determined by renal relapses during follow-up only. Slow, progressive renal failure without relapses is rarely observed in this group.