Serum and Urine Monocyte Chemoattractant Protein-1 as A Markers for Lupus Nephritis

Lupus nephritis (LN) is a common major organ manifestation and main cause of morbidity and mortality of the disease. We aimed to determine the level of serum and urinary monocyte chemoattractant protein-1(sMCP-1 and uMCP-1) in systemic lupus erythematosus (SLE) patients with and without LN and analyze their association with different clinical and serologic parameters of disease activity. We enrolled 60 female patients with SLE (32 with LN and 28 without LN) and 20 controls.MCP-1 and anti-dsDNA were measured by ELISA. There was statistically significant increase in serum and urinary MCP-1 in all SLE patients (mean=711.59, 676.68 pg/ml respectively) as compared to the control group (mean= 635.70, 632.40 pg/ml respectively), P=0.034, 0.020 respectively. Among patients with LN there was statistically significant increase in sMCP-1 (mean=723.58) compared to the control group (P=0.038, and in uMCP-1 (mean=699.08) compared to patients without LN (mean=651.07) and control group (mean=632.40), P=0.007, 0.002 respectively. Urinary, but not serum MCP-1, positively correlated with 24 hour proteinuria, anti-dsDNA, renal SLEDAI ,biopsy activity index (r=0.362, P=0.004; r=0.303, P=0.019; r= 0.267, P=0.039; r=0.353, P=0.047 respectively) and negatively correlated with serum albumin (r=-0.329, P=0.010).There was statistically significant increase in uMCP-1 and anti-dsDNA in patients with poor response compared to patients with good response to immunosuppressant therapy (P= 0.025; P=0.034 respectively). In conclusion, uMCP-1 is associated with LN and disease activity and may be used as a useful tool for diagnosis and follow up.