Clinicopathological and long-term prognostic features of membranous nephropathy with crescents: a Japanese single-center experience.

Background: Three recent studies from the United States and China reported the clinicopathological features and short-term prognosis in patients with membranous nephropathy (MN) and crescents in the absence of secondary MN, anti-glomerular basement membrane (GBM) antibodies, and anti-neutrophil cytoplasmic antibodies (ANCA).

Methods: We compared clinicopathological and prognostic features in 16 MN patients with crescents (crescent group) and 38 MN patients without crescents (control group), in the absence of secondary MN, anti-GBM antibodies, and ANCA. Median follow-up periods in the crescent and control groups were 79 and 50 months, respectively.

Results: Decreased estimated glomerular filtration rates (<50 mL/min/1.73 m), glomerulosclerosis, and moderate-to-severe interstitial fibrosis were more frequently observed in the crescent group than in the control group (P = 0.043, P = 0.004, and P = 0.035, respectively). Positive staining rates for glomerular IgG2 and IgG4 were significantly different between the 2 groups (P = 0.032, P = 0.006, respectively). Doubling of serum creatinine during follow-up was more frequently observed in the crescent group than in the control group (P = 0.002), although approximately two-thirds of patients in the crescent group were treated with immunosuppressive therapy. Crescent formation and interstitial fibrosis were risks for doubling of serum creatinine [hazard ratio (HR) = 10.506, P = 0.012; HR = 1.140, P = 0.009, respectively].

Conclusions: This is the first Japanese study demonstrating significant differences in clinicopathological and prognostic features between the 2 groups. Most patients in the crescent group may develop a long-term decline in renal function despite immunosuppressive therapy.