Background and aims Lupus Nephritis (LN) is one of the most serious manifestations and the strongest predictors of poor outcome in systemic lupus erythematosus (SLE). Recent evidence showed a potential role of interleukin-17 (IL-17) in the pathogenesis of LN. However, the correlation between IL-17 level and the severity of LN remains incompletely understood.

Objective To analyse IL-17 serum in LN and non LN patients and its correlation with disease activity measured by Systemic Lupus Activity Measure (SLAM) score.

Methods A cross sectional design was conducted with 40 SLE patients consisted of 22 LN (group 1) and 18 non LN (group 2). We used SLICC criteria to diagnose SLE, ACR to diagnose LN with urinalysis, and ELISA to measure IL-17 concentration.

Results Mean age group 1 25.68±7.12 y.o and 27.11±6.79 y.o in group 2. The mean differences of proteinuria, CRP, IL-17, and SLAM score between group 1 and group 2 were 4.73 mg (90.9% proteinuria +3) vs 2.06 mg; 1.64±0.89 vs 1.33±0.59; 9.64±1.64 vs 8.69±0.76; 16.36±5.30 vs 11.11±5.22. The correlation between IL-17 and SLAM score was 0.018 (p<0.05 ) in group 1 and 0.35 (p>0.05) in group 2.

Conclusions Lupus Nephritis has higher IL-17 serum level and SLAM score compared to non lupus nephritis. There is significant correlation between IL-17 and SLAM score in LN but not significant in non LN.