[Circulating immune complexes and anti-IgG antibodies in rheumatoid arthritis].

Anti-IgG antibodies were studied in 222 patients hospitalized in a Rheumatology service using "radio-immuno-precipitation-PEG-assay" (RIPEGA), The presence of anti-IgG antibodies was observed in 94 per cent of sero-positive rheumatoid arthritis (RA+), 88 percent of seronegative rheumatoid arthritis (RA--), 50 percent miscellaneous chronic inflammatory rheumatisms (CIR) and 77 percent of no-classifiable chronic inflammatory rheumatisms. The study of circulating immune complexes (CIC) using the CIC-125 I linkage tests, carried out on 101 RA cases, demonstrated their presence in 80 per cent of RA+ and 85 per cent of RA--. The comparison of these two factors during RA showed a concordant relationship that was statistically significant. The presence of the rheumatoid factor (RF) in the form of complexes in the blood stream, is discussed.