Background Rheumatoid arthritis (RA) - an autoimmunological inflammatory joint disease and osteoarthritis (OA) inducing chronic degradation of articular cartilage, with a possible secondary inflammatory process, release the degradation products of extracellular matrix into synovial fluid. Released fragments of matrix molecules may be detected in joint fluid (SF), blood and urine.

Objectives We studied correlation between the concentration of collagenes degradation products, sulfated glycosaminoglycans (GAGs) and specific activity of N-acetyl-β-hexosaminidase (HEX) in synovial fluid of patients with RA and OA.

Material and methods: The study was conducted in RA 20 patients, 13 females and 7 males (mean age 43±18 years, mean disease duration 10.3±5.2 years), OA 20 patients, 12 females and 8 males (mean age 56±26 years, mean disease duration 12.3±5.2 years) and matched 10 healthy persons (6 women, 4 men, mean age 42±19 years) with no history of injures or joint disease. SF samples were aspirated from the knee joints of patients during routine therapeutic procedures. The determinations in SF were determined by the methods: Komsa-Penkova et. al.(1996)-collagen; Farndale et. al.(1992)- sulfated GAGs; Marciniak et. al.(2004)- HEX activity.

Results The concentration of the collagenes degradation products was significantly lower in SF of patients with OA (4.54±1.38 mg/ml) in comparison to RA (6.98±2.44 mg/ml). The concentration of GAGs in RA and OA was not significantly different. The specific activity of HEX in RA SF (26.67±11.5 μkat/kg of protein) was significantly higher in comparison to OA SF (5.33±3.28 μkat/kg of protein).

Conclusions The SF concentration of the collagen degradation products and GAGs, positively correlate with HEX activity in RA and OA patients. The HEX activity in SF may be a marker of destruction the cartilage extracellular matrix.

Disclosure of Interest None Declared