Rheumatoid factor in Nigerian sera

Abstract

A high prevalence of rheumatoid factor has been found in the sera of apparently healthy inhabitants of two Western Nigerian villages. The prevalence of rheumatoid factor at high titre increased markedly with age. The rheumatoid factor found in the sera of these apparently healthy subjects showed a selective affinity for human γ-globulin rather than rabbit γ-globulin. Rheumatoid factor activity was shown to be restricted to the serum IgM fraction. In one of the two villages a significant correlation was found between the presence of rheumatoid factor at high titre and the presence of IgM malaria antibodies at high titre and the possible role of malaria in the induction of rheumatoid factor formation in these two communities is discussed.