Diagnostic values of serum IL-17A and IL-18 in Rheumatoid arthritis and Correlation with treatment

Abstract

Background: Rheumatoid arthritis (RA) is an autoimmune disorder that involves autoantibodies attacking and weakening joints. RA is characterized by leukocyte (Monocyte, Lymphocyte mast cell .etc) infiltrations into the synovial compartment leading to inflammation in the synovial membrane.   Synovitis leads to the release of pro-inflammatory cytokines, matrix metalloproteinases, chemokines, complement proteins, and growth factors.

Objective: The current study pointed to verify the diagnostic values of interleukin -17 A and interleukin -18 in Rheumatoid arthritis (RA) patients and the effect of treatment thereon.

Study subjects and methods: A total of 88 samples with RA were selected from the health clinics of AL-Yarmouk teaching hospital/rheumatology clinic in Baghdad, with female rheumatoid arthritis patients as the patient group (50) and (38) healthy females as the control group. All patients were exposed to clinical, laboratory, and ultrasound assessments, besides measuring the serum level of both (IL-17A and IL-18) by the method of Enzyme-linked immunosorbent assay (ELISA).

Results: The results show that there is a significant difference (p≤0.05) in IL-17A levels between patients and controls. The concentration of IL-17A in premenopausal patients is higher when compared to control groups (18.06 ± 3.85 vs 15.71 ± 1.82 pg/ml), so, the concentration in postmenopausal studied groups (17.19 ± 2.91 vs 14.13 ± 1.06 pg/ml).

Also, there are significant differences (p≤0.05) in the level of IL-18 between the patients and the control; it is found that the level of IL-18 within the premenopausal patients was higher compared to the control (16.09 ± 9.69 vs 12.52 ± 8.30 pg/ml).

Conclusion: A High level of IL-17A in RA patients contributes to the pathogenesis of RA as an inflammatory disease. As well as, the elevated levels of IL-18 suggest its physiological role to induce inflammatory disorder Treatment with (MTX and Etanercept) causes a decrease in the inflammatory markers of this disease RF in patient groups.