Clinical Significance of Serum C1q-Circulating Immune Complexes in Patients with Lupus Nephritis / 대한류마티스학회지

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate whether serum C1q-circulating immune complexes (C1q-CIC) serve as a predictive marker for renal flares in patients with lupus nephritis. METHODS: Twenty-five patients with lupus nephritis and 24 healthy controls were enrolled. Patients with lupus nephritis had their serum C1q-CIC titers and other serologic parameters such as serum C3, C4, anti-dsDNA antibody, and erythrocyte sedimentation rate measured simultaneously. The systemic lupus erythematosus disease activity index (SLEDAI) was also checked. RESULTS: Serum C1q-CIC titers were higher in patients with lupus nephritis than in healthy controls (109.33+/-53.79 microg/mL vs. 75.28+/-22.91 microg/mL, p=0.008). A statistically significant association was found between serum C1q-CIC titers and C3 (p=0.011), C4 (p=0.027), and anti-dsDNA antibody (p=0.014). SLEDAI was also correlated with serum C1q-CIC titers (p=0.022). CONCLUSION: Serum C1q-CIC appears to be related to renal disease activity in patients with lupus nephritis. These results suggest that serum C1q-CIC is a predictive marker for renal flares in patients with lupus nephritis.