Comparison of complement-fixing antibody titres in patients with rheumatoid arthritis and matched controls.

Many of the clinical findings in rheumatoid arthritis are consistent with an infectious aetiology. Direct methods of demonstrating infectious agents in rheumatoid tissues have given apparently conflicting results (Bartholomew, 1967; Duthie, Stewart, Alexander, and Dayhoff, 1967; Sharp, 1970). Indirect evidence, namely the demonstration of differences in titres of antibodies against different antigens between rheumatoid patients and normal people, has again given conflicting results (Smiley and Casey, 1969; Chandler, Robinson and Masi, 1971). This report describes differences in thecomplementfixing antibody titres between a group of rheumatoid patients and controls who were matched for age and sex.