Urinary MCP-1 as a biomarker for lupus nephritis: a meta-analysis

Abstract

This study aimed to evaluate whether urinary monocyte chemoattractant protein-1 (MCP-1) could serve as a biomarker for lupus nephritis (LN). We performed a meta-analysis to examine the relationship between urinary MCP-1 level and LN in three comparisons: active LN versus inactive LN, active LN versus control, and inactive LN versus control. Eight studies of a total of 399 patients with LN (204 with active LN, and 195 with inactive LN) and 130 controls were available for this meta-analysis. The meta-analysis revealed that the urinary MCP-1 level was significantly higher in the active-LN group than in the inactive-LN group (standard mean difference [SMD] = 1.883, 95 % confidence interval [CI] = 0.811-2.954, p = 0.001). The meta-analysis showed that the urinary MCP-1 level was significantly higher in the active-LN group than in the control group (SMD = 3.085, 95 % CI = 1.684-4.485, p = 1.6 x 10(-5)). Furthermore, stratification by ethnicity showed significantly elevated urinary MCP-1 levels in the active-LN group in Caucasian, Asian, and Egyptian populations (SMD = 2.408, 95 % CI = 1.711-3.105, p < 1.0 x 10(-8); SMD = 1.020, 95 % CI = 0.623-2.153, p = 4.6 x 10(-7); and SMD = 7.370, 95 % CI = 1.467-2.157, p = 5.9 x 10(-5), respectively). The meta-analysis indicated that the urinary MCP-1 level was also significantly higher in the inactive-LN group than in the control group (SMD = 1.812, 95 % CI = 0.628-2.996, p = 0.003). The meta-analysis demonstrated that urinary MCP-1 was significantly higher in patients with active LN than in those with inactive LN and control subjects, and the patients with inactive LN showed significantly higher urinary MCP-1 levels than the controls.