[Stromelysin-1 (MMP-3) level in the sera from patients with rheumatoid arthritis and other connective tissue diseases--clinical significances in early onset rheumatoid arthritis].

Stromelysin-1 (MMP-3) is a metalloproteinase that degrades articular cartilage matrix in patients with rheumatoid arthritis (RA). We measured MMP-3 in the sera from patients with RA and other connective tissue diseases using specific sandwich EIA and studied its clinical significance in early onset RA. MMP-3 level in healthy control (n = 170) was significantly higher in male than in female. The level of MMP-3 in RA was significantly and dramatically higher than in healthy control, osteoarthritis, systemic lupus erythematosus, progressive systemic sclerosis, primary sjogren's syndrome, mixed connective tissue disease, gouty arthritis and traumatic arthritis. Serum MMP-3 significantly correlated with serum BUN or serum creatinine levels in SLE patients but not in RA patients. In early onset RA, serum MMP-3 level was significantly elevated. Furthermore, when the relationship between the serum MMP-3 level and X-ray findings of the joints in RA was studied, it was found that MMP-3 level was elevated even in stage I or II and that there was no statistical differences between stage I or II and stage III or IV, suggesting that serum MMP-3 level is elevated in the early stage of initial inflammatory process when only mild cartilage degradation is seen. These results suggest that measurements of serum MMP-3 is an important tool for establishing diagnosis of early onset RA, and that serum MMP-3 level may be a marker of cartilage destruction and of estimating therapeutic efficacy in early onset RA.