Detection of anti-Proteus antibodies in sera of patients with rheumatoid arthritis.

This study was carried out to determine increased level of antibodies to certain bacteria in rheumatoid arthritis (RA) patients. Fifty RA patients and 25 each of those suffering from osteoarthritis (OA) and healthy controls were tested for antibodies to somatic ('O) and flagellar ('H') antigens of Proteus mirabilis, Escherichia coli, and for antibodies to 'O' antigen of Klebsiella pneumoniae by standard tube agglutination method. Anti-Proteus antibodies against 'O' and 'H' antigens could be demonstrated in 70% and 64% RA cases respectively, and were statistically significant. Antibodies could be demonstrated against E. coli 'O' and 'H' antigens in 86% and 92% RA cases respectively, and were statistically significant. Against K. pneumoniae 'O' antigen, no antibody could be demonstrated in any of RA and OA cases, and healthy controls. Of the 50 RA patients, 30 had raised CRP levels. Antibodies against P. mirabilis and E. coli antigens appeared to be independent from CRP. Thus a specific elevation in the immune response to P. mirabilis and E. coli has been demonstrated in patients with RA from India.

Elevated levels of anti-proteus antibodies in patients with active rheumatoid arthritis.

We carried out this study to determine if our patient population with rheumatoid arthritis (RA) has elevated levels of antibodies to gut bacteria. Seventy patients with RA were categorised as being either active or inactive on clinical grounds. Antibodies to the H and O antigens of Proteus mirabilis and Salmonella typhi were determined by tube agglutination method in these patients, 18 patients with osteoarthritis and 82 healthy controls. There was no significant difference in the anti-proteus antibody titres between both the control groups and patients with inactive disease. However, antibody levels among patients with active disease were significantly higher than controls (P < 0.001). There was no significant difference in anti-salmonella antibody titres among the various disease and control groups. Elevated antibody levels could suggest a role for Proteus as an etiological agent in RA.

Anti-proteus antibodies in rheumatoid arthritis

Antibodies [Abs] to Proteus mirabilis and Escherichia Coli in 14 active rheumatoid arthritis [RA], 16 inactive RA and 20 healthy controls were measured using the indirect immunofluorescence technique. The mean titres to Proteus mirabilis were found significantly higher in active RA patients than in the other two groups [P < 0.001]. On the other hand, the mean titres to E. coli were not significantly elevated in the three groups. These results emphasized the importance of searching for an environmental factor during the acute phase of the disease, either directly by looking for a microbial or viral antigens or indirectly by testing for [Abs] titres against particular micro organism. Proteus mirabilis is one of these organisms