Long-term observations of clinicopathological characteristics and outcome of Japanese patients with pauci-immune crescentic glomerulonephritis

The clinicopathological characteristics and outcome with pauci-immune crescentic glomerulonephritis (CreGN) are presumed to vary over time. We examined the characteristics and outcome of Japanese patients with CreGN according to the treatment periods. From 1968 to 2011, we examined a total of 102 patients diagnosed with pauci-immune CreGN by renal biopsy. The patients were divided into three groups according to the treatment periods-Group I (1968-1988, n = 18), Group II (1989-2001, n = 37; when the nationwide survey of rapidly progressive glomerulonephritis [RPGN] was performed in Japan), and Group III (2002-2011, n = 47; after publication of the Japanese guideline for RPGN). There were no significant differences in blood pressure, renal function or anti-neutrophil cytoplasmic antibody titer between groups. On the other hand, the rate of crescent formation and degree of interstitial inflammatory cell infiltration were decreased in Group III. Serum creatinine (< 3.0, 3.0-6.0, a parts per thousand yen6.0 mg/dL) and crescent formation (< 30, 30-50, 50-80, a parts per thousand yen80 %) were significant renal prognostic factors in Group III [serum creatinine: hazard ratio (HR) 4.79, 95 % confidence interval (CI) 1.43-16.1, P = 0.011; crescent formation: HR 2.86, 95 % CI 1.06-7.73, P = 0.039]. Furthermore, renal survival rate of patients with crescent formation < 50 % and patient survival rate of patients with serum creatinine < 3 mg/dL were improved in Group III. Patients with CreGN were diagnosed in the early phase of crescent formation and outcome has improved in recent years.