CHONDROITIN AND KERATAN SULFATE EPITOPES, GLYCOSAMINOGLYCANS, AND HYALURONAN IN PROGRESSIVE VERSUS NONPROGRESSIVE OSTEOARTHRITIS

Objective-To determine if a single time point estimation of chondroiti n sulphate (CS) or keratan sulphate (KS) epitopes, hyaluronan (HA), or total glycosaminoglycans (GAG) in knee synovial fluid at time of hosp ital referral can predict subsequent radiographic progression of knee osteoarthritis. Methods-Two groups of hospital referred patients with knee osteoarthritis were compared: (1) a ''progressive'' group (n = 45 ), showing further reduction in radiographic joint space of at least o ne grade (0-3) in at least one compartment; and (2) a ''non-progressiv e'' group (n = 25) in whom radiographs showed no change during the mea n follow up period of 2.3 years (median 2, range 1 to 5 years). Knee s ynovial fluid obtained at the first visit was examined by ELISA for: C S epitopes, using monoclonal antibodies 3B3 and 7D4; KS epitope, using monoclonal antibody 5D4; and HA, using biotinylated HA binding region of cartilage proteoglycan. Total sulphated GAG were measured by dye b inding with 1:9 dimethylmethylene blue. Results-In patients with bilat eral synovial fluid data right and left knee values were closely corre lated for all variables. There were no significant differences between CS and KS epitopes, HA, total sulphated GAG, or ratios of individual CS or KS epitopes to total GAG, between progressive and non-progressiv e groups. Conclusions-Single time point estimation of CS, KS, HA, or t otal GAG in synovial fluid does not distinguish radiographically progr essive and non-progressive knee osteoarthritis patients followed for t wo years.