Generic placeholder image

Current Rheumatology Reviews


ISSN (Print): 1573-3971
ISSN (Online): 1875-6360

Research Article

Interleukin 6 Concentration in Synovial Fluid of Patients with Inflammatory and Degenerative Arthritis

Author(s): Anna Mihailova*

Volume 18, Issue 3, 2022

Published on: 25 March, 2022

Page: [230 - 233] Pages: 4

DOI: 10.2174/1874471015666220128113319

open access plus


Aim: The present study aims to compare interleukin 6 concentration in synovial fluid in patients with known types of arthritis.

Background: Persistent synovitis without known markers, such as Rheumatoid Factor (RF), Anti- Citrullinated Protein Antibodies (ACPA), and genetic markers as HLA-B27, is not uncommon. It is valuable to determine the presence of chronic inflammation and put it in correlation with agerelated changes, which are especially relevant for middle-aged patients with mono- or oligoarthritis, when the dilemma to start disease-modifying drugs for inflammatory disease often is present. Interleukin 6 (IL-6) plays a significant role in chronic inflammation.

Objectives: IL-6 concentration in synovial fluid reflects the presence and activity of joint inflammation.

Methods: Synovial fluid was obtained from 101 patients with chronic synovitis. IL-6 concentration was determined by the immunochemical luminescence method.

Results: The median IL-6 concentration in synovial fluid in patients with osteoarthritis (OA) was 138.0 pg/ml (interquartile range (IQR) 43.4 to 296.0); in patients with rheumatoid arthritis was 2516.5 pg/ml, (IQR 1136.0 to 25058.0); in reactive arthritis 2281.0 pg/ml (IQR 1392.0 to 8652.0); psoriatic arthritis 1964.0 pg/ml (IQR 754.0 to 7300.0); ankylosing spondylitis 2776.0 pg/ml (IQR 514.7, 3944.0); in a group with negative RF, ACPA and HLA-B27 inflammatory arthritis 2163.0 pg/ml (IQR 822.0 to 7875.0). There is statistically significant difference of IL-6 concentration comparing OA and each inflammatory arthritis group, p<0.0001.

Conclusion: IL-6 detection in the synovial fluid is helpful in arthritis evaluation. The results show that an IL-6 level over 1000 pg/ml suggests the diagnosis of inflammatory arthritis.

Keywords: Interleukin 6, synovial fluid, synovitis, inflammation, inflammatory arthritis, osteoarthritis.

Graphical Abstract
Tanaka T, Narazaki M, Kishimoto T. IL-6 in inflammation, immunity, and disease. Cold Spring Harb Perspect Biol 2014; 6(10): a016295.
[] [PMID: 25190079]
Laavola M, Leppänen T, Hämäläinen M, et al. IL-6 in osteoarthritis: Effects of pine stilbenoids. Molecules 2018; 24(1): 109.
[] [PMID: 30597965]
Sack U, Kinne RW, Marx T, Heppt P, Bender S, Emmrich F. Interleukin-6 in synovial fluid is closely associated with chronic synovitis in rheumatoid arthritis. Rheumatol Int 1993; 13(2): 45-51.
[] [PMID: 8356390]
Swaak AJ, van Rooyen A, Nieuwenhuis E, Aarden LA. Interleukin-6 (IL-6) in synovial fluid and serum of patients with rheumatic diseases. Scand J Rheumatol 1988; 17(6): 469-74.
[] [PMID: 3266031]
Holt I, Cooper RG, Hopkins SJ. Relationships between local inflammation, interleukin-6 concentration and the acute phase protein response in arthritis patients. Eur J Clin Invest 1991; 21(5): 479-84.
[] [PMID: 1752286]
Hovdenes J, Kvien TK, Hovdenes AB. IL-6 in synovial fluids, plasma and supernatants from cultured cells of patients with rheumatoid arthritis and other inflammatory arthritides. Scand J Rheumatol 1990; 19(3): 177-82.
[] [PMID: 2359995]
Bertazzolo N, Punzi L, Stefani MP, et al. Interrelationships between interleukin (IL)-1, IL-6 and IL-8 in synovial fluid of various arthropathies. Agents Actions 1994; 41(1-2): 90-2.
[] [PMID: 8079829]
Radojčić MR, Thudium CS, Henriksen K, et al. Biomarker of extracellular matrix remodelling C1M and proinflammatory cytokine interleukin 6 are related to synovitis and pain in end-stage knee osteoarthritis patients. Pain 2017; 158(7): 1254-63.
[] [PMID: 28333699]
Tsuchida AI, Beekhuizen M, Rutgers M, et al. Interleukin-6 is elevated in synovial fluid of patients with focal cartilage defects and stimulates cartilage matrix production in an in vitro regeneration model. Arthritis Res Ther 2012; 14(6): R262.
[] [PMID: 23206933]
Beekhuizen M, Gierman LM, van Spil WE, et al. An explorative study comparing levels of soluble mediators in control and osteoarthritic synovial fluid. Osteoarthritis Cartilage 2013; 21(7): 918-22.
[] [PMID: 23598178]
Matsumoto T, Tsurumoto T, Shindo H. Interleukin-6 levels in synovial fluids of patients with rheumatoid arthritis correlated with the infiltration of inflammatory cells in synovial membrane. Rheumatol Int 2006; 26(12): 1096-100.
[] [PMID: 16738904]
Kotake S, Sato K, Kim KJ, et al. Interleukin-6 and soluble interleukin-6 receptors in the synovial fluids from rheumatoid arthritis patients are responsible for osteoclast-like cell formation. J Bone Miner Res 1996; 11(1): 88-95.
[] [PMID: 8770701]
Swärd P, Frobell R, Englund M, Roos H, Struglics A. Cartilage and bone markers and inflammatory cytokines are increased in synovial fluid in the acute phase of knee injury (hemarthrosis)--a cross-sectional analysis. Osteoarthritis Cartilage 2012; 20(11): 1302-8.
[] [PMID: 22874525]
Irie K, Uchiyama E, Iwaso H. Intraarticular inflammatory cytokines in acute anterior cruciate ligament injured knee. Knee 2003; 10(1): 93-6.
[] [PMID: 12649034]
Siqueira MB, Frangiamore S, Klika AK, Gajewski N, Barsoum WK, Higuera CA. Comparison of synovial fluid cytokine levels between traumatic knee injury and end-stage osteoarthritis. J Knee Surg 2017; 30(2): 128-33.
[] [PMID: 27123668]

© 2023 Bentham Science Publishers | Privacy Policy