Shereen KAMEL1, Rehab KHALAF1, Hend MONESS2,Shimaa AHMED1

1Department of Rheumatology and Rehabilitation, Faculty of Medicine, Minia University, Minia, Egypt
2Department of Clinical Pathology, Faculty of Medicine, Minia University, Minia, Egypt

Keywords: Interleukin-17, knee, osteoarthritis, serum, synovial fluid.


Objectives: This study aims to assess the serum and synovial fluid (SF) levels of interleukin (IL)-17A in primary knee osteoarthritis (KOA) patients and to study their correlations with functional status, pain, and disease severity.

Patients and methods: This cross-sectional study was conducted between December 2017 and March 2018 and it included 70 patients (46 males, 24 females; mean age 57.3±10.0 years; range 34 to 76 years) with primary KOA and 30 age-, sex-, and body mass index-matched healthy individuals (20 males, 10 females; mean age 53.3±10.3 years; range, 35 to 70 years). Western Ontario and McMaster Universities osteoarthritis index (WOMAC), visual analog scale (VAS), Lequesne index, and Kellgren and Lawrence (KL) grading scale were used for assessment of the disease. IL-17A levels were measured in the serum for patients and healthy controls, and in SF for patients only using an enzyme-linked immunosorbent assay.

Results: Serum levels of IL-17A were significantly higher in KOA patients than controls (p=0.04). A positive correlation was found between serum and SF IL-17A levels. Serum and SF IL-17A levels had positive correlations with VAS, WOMAC pain score, Lequesne pain score, WOMAC function score, and Lequesne index. SF IL-17A levels had strong positive correlations with radiographic severity (KL grade) and duration of OA.

Conclusion: Higher IL-17A levels in primary KOA patients were significantly associated with longer disease duration, higher pain scores, worse quality of life, extreme disability, and advanced structural damage. Therapeutics that target IL-17A warrant further investigation.

Citation: Kamel S, Khalaf R, Moness H, Ahmed S. Serum and synovial fluid levels of interleukin-17a in primary knee osteoarthritis patients: correlations with functional status, pain, and disease severity. Arch Rheumatol 2022;37(2):187-194.

Ethics Committee Approval

The study protocol was approved by the Faculty of Medicine Ethics Committee. The study was conducted in accordance with the principles of the Declaration of Helsinki.

Author Contributions

Wrote manuscript: S.K.; Contributes to preparation: R.K.; Measured IL-17 in all patients: H.M.; Performed analytic calculation: S.A.

Conflict of Interest

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Financial Disclosure

The authors received no financial support for the research and/or authorship of this article.