Serum lipoxin A4 as a biomarker for systemic lupus erythematosus

Abstract

Introduction Systemic lupus erythematosus (SLE) is an immune-complex mediated autoimmune disease characterized by protean clinical manifestations and fluctuating disease course. It was proposed that progression and flares of lupus and lupus nephritis are due to decreased production of lipoxin A4 (LXA4) and enhanced production of leukotrienes by the renal tissue and/or infiltrating leukocytes and macrophages. Objective The aim of this study was to assess the levels of serum LXA4 in SLE patients and in healthy controls, and to correlate them with various clinical and laboratory data as well as renal biopsy and disease activity indices. Patients and methods Forty adult female SLE patients were included in this study. The SLE patients were divided into two groups: group I included 20 patients without nephritis and group II included 20 patients with nephritis. Forty apparently healthy age-matched women served as the control group. Patients and controls were assessed for serum LXA4 using enzyme linked immunosorbent assay. Disease activity was assessed using systemic lupus erythematosus desease activity index (SLEDAI) and renal SLEDAI. Renal biopsy was performed for patients with lupus nephritis. Results SLE patients showed a higher median level of serum LXA4 compared with the control group (0.24 vs. 0.15 ng/ml), but with no significant statistical difference (P = 0.097). Moreover, there was no statistically significant difference in serum LXA4 between SLE patients with and without nephritis and the control group (P = 0.142). There was no significant correlation between serum LXA4 and various clinical and laboratory data, as well as renal biopsy and disease activity index. Conclusion LXA4 was suggested to be an important biomarker to search for in SLE. Our study showed no significant statistical difference between SLE patients and the control group as regards serum LXA4. Assessment of urinary LXA4 is recommended as it may be more valuable than serum LXA4 in reflecting organ affection in SLE, as well as disease activity, and comparing it with serum LXA4 level.