Significance of histological crescent formation in patients with diffuse proliferative lupus nephritis.

BACKGROUND Although crescentic nephritis is not rare in diffuse proliferative lupus nephritis (DPLN), little is known about the clinicopathological features in DPLN with crescents worldwide. This study was undertaken to investigate the clinicopathological features and outcome of Chinese DPLN patients with different degrees of crescents. METHODS 520 DPLN patients with more than 10% histological crescents (cDPLN) were enrolled in this retrospective study. They were divided into three groups: group 1 (10%≤ crescents <25%, n = 240), group 2 (25%≤ crescents <50%, n = 160), and group 3 (crescents ≥50%, n = 120). Another 100 patients without histological crescents were enrolled as a control group. Clinicopathological features, treatment responses, and outcomes were compared among the four groups. RESULTS There were 450 (86.6%) females and 70 (13.4%) males with an average age of 31.7 ± 11.4 years. Compared with the control group, cDPLN patients had shorter lupus nephritis duration (20.7 ± 34.1 vs. 30.4 ± 48.9 months), higher prevalence of rapidly progressive glomerulonephritis syndrome (21.8%), and gross hematuria (26.7%). Laboratory findings indicated more severe hypoproteinemia, hyperlipidemia, and renal insufficiency; heavier proteinuria and microscopic hematuria; higher tubular injury parameters, and lower serological activity in crescentic groups. Histologically, cDPLN patients have severe glomerular and tubulointerstitial lesions as well as extensive leukocyte infiltration together with a lesser degree of immune complex deposition. The proportion of death, end-stage renal disease, and treatment failure correlates positively with the degree of histological crescents. CONCLUSIONS cDPLN patients with acute onset and short disease duration mostly show severe renal manifestations, less extrarenal organ involvement, lower serological activity, serious capillary necrosis, severe tubulointerstitial inflammation, atrophy and fibrosis, prominent leukocyte infiltration, less glomerular immune complex deposition, poor treatment response, and worse renal outcome.