Abstract
Thirteen patients were studied after jejunoileal bypass (JIB) surgery. Seven developed arthritis and six did not. Circulating immune complexes containing IgG and IgA were detected in the sera of patients with and without arthritis. IgA complexes were shown to contain secretory component, a protein predominantly associated with intraluminal IgA, in significantly higher levels in patients with arthritis. Analytical ultracentrifugation showed complexes of approximately 10 X 8S, consistent with the size of secretory IgA. Arthritis after JIB appears to be associated with circulating immune complexes containing secretory IgA.