[Rheumatoid arthritis with monoclonal gammopathy. Retrospective review of twelve case-reports (author's transl)].

Monoclonal gammopathy (MG) occurs in the course of rheumatoid arthritis (RA) in approximately 3.7% of cases. Twelve such cases were compared to two-hundred and fifteen controls with RA. RA was of later onset in patients with MG. Patients with MG had lower latex and Rose-Waaler titers; a decrease in these titres heralded onset of MG. The twelve patients with both RA and MG were then compared to nine-hundred and seventy-one controls with monoclonal gammopathy. As in previous studies, we recorded both IgM excess and unexplained lambda light chain excess.