Serum Levels of Interleukin-2 in a Cohort of Egyptian Systemic Lupus Erythematosus Patients with Glomerulonephritis

Background Lupus nephritis is a serious complication of systemic lupus erythematosus(SLE).It is clinically evident in 50-60% of SLE patients, and it is histologically evident in most SLE patients. Defective Interleukin-2(IL-2) production contributes to the unbalanced immune system in SLE. Aim of the Work To evaluate the relationship between serum IL-2 level and renal involvement in SLE patients. Patients and Methods 60 adult SLE patients were studied. SLE Disease Activity Index-2000 (SLEDAI-2K) and serum IL-2 level by ELISA were assessed. Results Patients were (93.3%) females and (6.7%) males; their ages (19- 58 years) with median disease duration 4 (0.25-24years). The median IL-2 level was significantly lower in SLE patients with nephritis 25.5 ng/L (5-90 ng/L) than in patients without nephritis 53.5 ng/L (29-165 ng/L) (p ≤ 0.001). There was negative correlation between serum IL-2 and serum creatinine (r= -0.494 p ≤ 0.001) and between serum IL-2 and protein/creatinine ratio (r=-0.512 p ≤ 0.001). Although there was no relationship between SLE disease activity and serum IL-2; the level of serum IL-2 was higher with mild SLE disease activity (45-60 ng/L) followed by moderate activity (15-135 ng/L) and the lowest with high disease activity (5-165 ng/L). An increase in s.creatinine and a decrease in S.IL-2 had an independent effect on increasing probability of occurrence of nephritis in SLE patients (p < 0.01). Conclusion Serum IL-2 might have an important role in predicting the occurrence of lupus nephritis in SLE.