Aim: To assess the potential usefulness ,of measurements of serum levels of cartilage
oligomeric matrix protein (COMP) and YKL-40 in patients with knee osteoarthritis (OA)
as biochemical markers of osteoarthritic status.
Methods: 40 patients having symptomatic knee OA and meeting the ACR criteria for
idiopathic knee OA and 15 healthy subjects matched with age and sex as controls were
included in this study. Serum COMP and YKL-40 levels were measured by ELISA tech
nique. The levels of these markers were compared according to the changes in joint
space width (JSW), Kellgren Lawrence (K-L) grade, age, disease duration, gender, body
mass index (BMI) and western Ontario MacMaster (WOMAC) index in our OA patients.
Results: There were significant elevations of the serum COMP and YKL-40 in OA pa
tients in comparison to the control group (P<0.001), more in hilateral than unilateral cases.
There were highly significant positive correlations of both parameters with K-L radiological
severity of the disease, but an inverse significant correlation with JSW (P<0.001). As regard
• synovitis, there was significant increase of serum YKL-40 (P<0.05) while serum COMP
level showed a slight but insignificant increase. There were highly significant positive cor
relations of serum COMP and YKL-40 levels with WOMAC index and age (P<0.001)
while there were no significant correlations with disease duration and body mass index
(BMI) (P>0.05). C-reactive protein (CRP) was significantly higher in OA patients than in
controls and showed positive significant correlation with serum level of YKL-40 (P<0.001).
There was a positive highly significant correlation between both parameters (P<0.05).
Conclusion: From these results we concluded that, the raised levels of serum COMP
and YKL-40 can reflect disease severity and multiple joint involvement. YKL-40 may be
a useful marker of synovitis in OA. The combined use of both markers can help in early
diagnosis and improve prediction of disease status. |
