Epidemiology and temporal changes in the prognosis of rapidly progressive glomerulonephritis in Japan: a nationwide 1989-2015 survey.

Abstract

Rapidly progressive glomerulonephritis (RPGN) can progress to end-stage kidney disease within a short period. This study is a continuation of the chronological nationwide survey conducted by the Japan-RPGN working group. We examined a total of 2793 RPGN cases registered during four periods (1989-1998, 1999-2001, 2002-2008, 2009-2011) plus 1386 cases in 2012-2015. As potential prognostic determinants, we investigated the onset period, the clinical severity (CS) grade [classified according to age, serum creatinine (sCr) and C-reactive protein levels, and presence/absence of lung lesions], and causative disease. The cumulative overall RPGN patient survival at 24months kept improving over the five periods (72.0%, 72.9%, 77.7%, 83.0%, 84.9%, p < 0.001 for trend). The cumulative renal survival also improved in the latest period (68.7%, 75.4%, 76.7%, 73.4%, 78.2%, p < 0.001 for trend). The CS grade was well stratified to predict both life and renal prognoses. Anti-glomerular basement membrane disease (aGBMD)-RPGN had a poorer renal prognosis than other diseases. In anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV-RPGN, accounting for > 70% of the overall RPGN), the prognostic results were similar to that for overall RPGN. There was a much better renal prognosis for the latest period under the condition of sCr < 3mg/dL (the 24-month cumulative renal survival: 97.9%), but not for sCr ≥ 3mg/dL (61.5%). In overall RPGN as well as AAV-RPGN, both life and renal prognoses tended to improve, but the favorable renal result was substantially limited to mild cases. There was no improvement of the renal prognosis in aGBMD-RPGN.