Clinical study of calprotectin in gout and its complications

Objective To explore the role of calprotectin in gout and its complications. Methods A total of 49 patients with gouty arthritis were selected,including 24 patients with acute attack of gout,25 patients with remission of gout and 40 healthy controls. Serum calprotectin levels were detected by enzyme-linked immunosorbent assay(ELISA). The differences of calprotectin levels were compared between healthy control,patients with acute gout attack and remission. And the correlations were examined between calprotectin level and serum levels of creatinine and urea nitrogen in gout patients. Concurrently,the changes of serum calprotectin level in gout patients with or without kidney stones and fatty liver were further analyzed. Results As compared with control group,the level of calprotectin spiked markedly in gout group7075.6(5095.59316.8) vs 2831.2(2124.83334.8),P<0.01and the level of calprotectin was significantly lower in remission group than that in acute attack group. The serum creatinine level was significantly higher in gout than that in control group(85.39±15.21 vs 70.86±12.85,P=0.025). Although no significant inter-group difference existed in urea nitrogen level,urea nitrogen level showed a rising trend in gout group(5.45±1.52 vs 4.47±1.12,P=0.075). Serum calprotectin level was positively correlated with serum creatinine level(r=0.396,P=0.012),but not with urea nitrogen level(r=-0.150,P=0.363). In gout group,no significant difference existed in calprotectin concentration between patients with and without kidney stones5873.6(3191.210712.0) vs 7095.4(5171.69357.2),P=0.524while calprotectin level was significantly higher in patients with fatty liver than that in those without fatty liver11515.6(6497.213320.4) vs 5873.6(3191.2,10712.0),P=0.002. Conclusion Involved probably in the pathogenesis of gout,calprotectin has a certain predictive effect on acute attack of gout. As for the complications of gout,calprotectin may be correlated with the formation of acute kidney injury and fatty liver. However,its role in the formation of kidney stones should be further explored.