Serum uric acid as a predictor for nephritis in Egyptian patients with systemic lupus erythematosus

Abstract

Objective Lupus nephritis (LN) is closely associated with hyperuricemia, and uric acid is considered a risk factor for renal involvement in systemic lupus erythematosus (SLE). This study aimed to examine the association between serum uric acid (SUA) level and LN development and progression in SLE patients with normal renal function. Methods A total of 60 SLE patients with normal renal function from Ain Shams University Hospital were selected and assigned to group 1 (30 patients with LN) and group 2 (30 patients without LN). All patients were subjected to history taking, clinical examination, disease activity assessment based on SLE disease activity index (SLEDAI) and renal SLEDAI (SLEDAI-R) scores, and laboratory investigations, including as SUA, complete blood count, blood urea nitrogen (BUN), serum creatinine, creatinine clearance, urine analysis, protein/creatinine ratio, 24-h urinary protein excretion, Antinuclear antibodies (ANA), anti-dsDNA antibody, and serum complement (C3, C4). Results Disease duration, SLEDAI score, and SUA level were higher in group 1 than in group 2 (p < 0.001). SUA level was positively correlated with SLEDAI and SLEDAI-R scores, proteinuria, urinary casts, renal biopsy class, disease activity and chronicity indices, BUN level, and serum creatinine level but was negatively correlated with creatinine clearance (p < 0.05). SUA was a predictor of LN development in SLE patients (sensitivity, 83.3%; specificity, 70%). Conclusion SUA is associated with the development of lupus nephritis in patients with normal kidney function also SUA in-dependently correlated with disease activity and chronicity in LN.