INCREASED SERUM LEVELS OF SOLUBLE CD44-ISOFORM V5 IN RHEUMATIC DISEASES ARE RESTRICTED TO SEROPOSITIVE RHEUMATOID-ARTHRITIS

Serum levels of sCD44v5 were measured in 134 patients with definite in flammatory rheumatic diseases (IRD) using a sandwich type ELISA. 94 pa tients suffered from erosive IgM-rheumatoid factor positive rheumatoid arthritis (RA+), 20 with undifferentiated seronegative polyarthritis, 12 with osteoarthropathia psoriatica and psoriasis vulgaris, 3 with s ystemic lupus erythematosus, 3 with scleroderma and 2 with reactive ar thritis. Elevated serum levels (> 58 ng/ml to 221 ng/ml; median: 93 ng /ml) were only detected in 54/94 (57%) patients with RA+, but not in o ther IRD. They correlated with advanced stages of disease (Steinbrocke r stages III + IV; p < 0.05), elevated CRP-levels (p < 0.01) and highe r measurements of IgM rheumatoid factor.