Using the Oxford classification of IgA nephropathy to predict long-term outcomes of Henoch-Schnlein purpura nephritis in adults

摘要

Recently, there has been emerging concern that crescents, the main histologic feature of Henoch鈥揝ch枚nlein purpura nephritis, merely reflect active inflammation, and may not be useful in predicting long-term outcomes. We therefore conducted a single-center retrospective study to evaluate whether the new Oxford classification of immunoglobulin A nephropathy can be used to predict long-term outcome in patients with Henoch鈥揝ch枚nlein purpura nephritis. We included 61 biopsy-proven patients with Henoch鈥揝ch枚nlein purpura nephritis between January 1991 and August 2010. In addition to the International Study of Kidney Disease in Children classification, pathologic findings were also evaluated by the Oxford classification. Primary outcomes were defined as either the onset of estimated glomerular filtration rate <60鈥塵l/min per 1.73鈥塵2 with 鈮?0% decrease in estimated glomerular filtration rate from baseline or end-stage renal disease. During a median follow-up of 49.3 months, 13 (21%) patients reached the primary end point. A Kaplan鈥揗eier plot showed that renal event-free survival was significantly longer in patients with <50% crescents than in those with crescents in 鈮?0% of glomeruli (P=0.003). Among the components of the Oxford classification, patients with endocapillary hypercellularity (E1; P=0.016) and tubular atrophy/interstitial fibrosis (T1/T2; P=0.018) had lower renal survival rates than those with E0 and T0. In a multivariate Cox model adjusted for clinical and pathologic factors, E1 (hazard ratio=8.91; 95% confidence interval=1.47鈥?3.88; P=0.017) and T1/T2 (hazard ratio=8.74; 95% confidence interval=1.40鈥?4.38; P=0.020) were independently associated with reaching a primary outcome, whereas the extent of crescentic lesions was not. Our findings suggest that the Oxford classification can be used in predicting long-term outcomes of Henoch鈥揝ch枚nlein purpura nephritis.