Serum Interleukin-17 Level in Patients with Rheumatoid Arthritis and its Relation to Disease Activity

Abstract

Background: Rheumatoid arthritis (RA) is a disease of progressive inflammatory autoimmune nature with articular and systemic effects. Its definite cause is unknown, but environmental and genetic factors are contributory. The aim of this study was to estimate the serum level of IL-17 in cases with RA and investigate its relation with disease activity among Egyptian population. Methods: This study included 20 RA cases and 20 healthy control subjects. All cases were subjected to full history taking, thorough clinical examination, laboratory investigations including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), anti-cyclic-citrullinated peptide (anti-CCP) antibodies and rheumatoid factor (RF). Enzyme linked immunosorbent assay was used to measure serum IL-17 level. Disease activity score-28 (DAS-28) was assessed. Results: The mean disease duration of the cases was 5.95±2.52 years (2-10years). DAS-28 ranged between 2.4 and 6.1 with a mean of 3.87±1.32. Serum IL-17 level was higher in the RA group (226.6±215.6 pg/ml) than the control group (48.17±54.9pg/ml) with p-value of <0.001. Significant correlations were found between IL-17 levels and the DAS-28, CRP, and hemoglobin. For detection of disease activity, IL-17 at a cut off value of > 98.2 pg/ml had sensitivity and specificity of 81.2% and 75%, respectively. Conclusions: Serum IL-17 level was significantly increased in cases with RA compared to healthy controls. Its significant correlation with DAS-28 suggested that serum IL-17 level could be an important marker of disease activity in RA.