A comparative study of the protein pattern in serum and synovial fluid.

A routine program for evaluation of the protein pattern in serum and synovial fluid has been tested on 25 patients in a consecutive study. The program comprised agar gel electrophoresis, total protein and albumin determination, and immunochemical determination of antitrypsin, orosomucoid, haptoglobin, IgR, and IgA. Linear correlation analysis of corresponding data in serum and synovial fluid gave r-values for the five latter components which varied from 0.74 to 0.87. On this basis reference intervals in synovial fluid could be established. Total protein, haptoglobin and IgG were elevated in rheumatoid arthritis, compared with osteoarthritis.