Source: www.medpagetoday.com/Rheumatology/Lupus/57445
by Nancy Walsh
Senior Staff Writer, MedPage Today

A greater number of glomerular crescents among patients with lupus nephritis was associated with deteriorating kidney function and severe adverse outcomes, a retrospective Chinese study found.

Among patients with crescents involving 50% or more of the glomeruli, the estimated 5- and 10-year survival rates were 78.9% and 52.6% compared with rates of 95.5% and 86.1% among those with fewer than 10% of crescents, according to Wei Chen, MD, PhD, and colleagues from Sun Yat-sen University in Guangzhou.

And in a multivariate analysis after adjustment for age, sex, proteinuria, and baseline kidney function, every 10% increase in crescents was an independent risk factor for a composite endpoint of doubling of the serum creatinine, end-stage renal disease, and death (HR 1.16, 95% CI 1-1.34, P=0.049), the researchers reported online in Lupus.

Crescents result from glomerular extracapillary proliferation and are typically cellular or fibrocellular. While it has been recognized that crescents being found in 50% or more of the glomeruli is a poor prognostic sign, little is known about outcomes with fewer crescents.

To address this knowledge gap, the researchers analyzed data from their hospital's lupus nephritis database, which included patients diagnosed from 1996 to 2011.

They identified 303 patients with crescents and 280 without. Baseline features associated with the presence of crescents were lower estimated glomerular filtration rate (eGFR 82 versus 108 mL/min/1.73 m2, P=0.001), higher blood pressure (133/84 versus 123/78, P<0 .001), worse proteinuria (1.95 versus="s" 1.08 g/24 h, P<0 .001), and more episodes of acute kidney injury (26.1% versus 8.2%, P<0 .001).

More severe disease activity also was seen among patients with crescents, with scores on the Systemic Lupus Erythematosus Disease Activity Index of 16 versus 12 (P<0 .001), on pathologic activity index scores (7 versus 3, P<0 .001), and on chronicity index scores (2 versus 1, P<0 .001).

After a median of 56 months, 16.8% of patients with crescents had a composite endpoint event, as did 13.9% of the noncrescent group, which was not a significant difference. There also were no differences in 10-year renal survival (86.2% versus 89.7%, P=0.637) or in 10-year patient survival (84.3% versus 89.2%, P=0.188).

Among the 303 patients with crescents, fewer than 10% of the glomeruli were affected in 29.4%, 31% had 10 to 19%, 15.5% had 20 to 29%, 9.2% had 30 to 39%, 5% had 40 to 49%, and 9.9% had 50% or more.

A total of 10.9% had class III nephritis, 65.3% had class IV, and 23.7% had class V.

On a hazard regression analysis, factors associated with the composite adverse outcome included age (HR 1.25 for every 10-year increase, 95% CI 1.01-1.55, P=0.037), lower eGFR (HR 1.13 for every 10 mL/min/1.73 m2 decrease, 95% CI 1.05-1.23, P=0.002), higher chronicity score (HR 1.23 for every 1-point increase, 95% CI 1.06-1.42, P=0.005), and proportion of crescents (HR 1.18 per 10% increase, 95% CI 1.05-1.33, P=0.004).

But in the multivariate analysis, only the proportion of crescents predicted the unfavorable prognosis.

"Our results demonstrated that the baseline conditions of the patients with crescents were much worse than in those without crescents; however, renal or patient survival did not differ between the two groups," the researchers noted.

A possible explanation for the absence of survival difference might be that crescents most commonly develop in class IV nephritis, when intensive immunosuppressive therapy is indicated, and this treatment, which can include intravenous pulsed methylprednisolone, and cyclophosphamide or mycophenolate mofetil (CellCept), "might account for the overall comparable prognosis," they suggested.

"Therefore, close attention should be paid to the lesions of crescents, and more prospective studies are needed to explore the optimal regimens for lupus nephritis patients with different proportions of crescents," they concluded.

Limitations of the study included its retrospective design and the heterogeneity of treatment regimens used.

The study was funded by the Ministry of Science and Technology of China, the National Natural Science Foundation of China, and Sun Yat-sen University.

Chen and co-authors disclosed no relevant relationships with industry.

Reviewed by F. Perry Wilson, MD, MSCE
Assistant Professor, Section of Nephrology, Yale School of Medicine

Primary Source
Lupus
Source Reference: Zhang W, et al "Clinical outcomes of lupus nephritis patients with different proportions of crescents" Lupus 2016; DOI: 10.1177/0961203316642312.