Detection of Mycobacterium avium Subspecies paratuberculosis in the Blood of Patients with Rheumatoid Arthritis by Using Serological and Molecular Techniques.

The role of Mycobacterium avium subspecies paratuberculosis (MAP) in triggering rheumatoid arthritis (RA) could be a population-specific phenomenon. This study explored the relationship between MAP and RA using serological and molecular techniques; In this case-control study, 239 Iranian participants, including 120 RA patients and 119 controls, were enrolled. The indirect ELISA was designed to diagnose antibodies against MAP3865c125-133 and Zinc transporter 8 (ZnT8)178-186. The Nested-Polymerase Chain Reaction (PCR) detected MAP in blood; The frequency of MAP in RA patients and controls was 31.9% and 12.5%, respectively (P = 0.002). The antibodies against MAP3865c125-133 and ZnT8178-186 were 42.9% and 37% in RA patients and 14.2% and 11.7% in the controls, respectively (P < 0.0001). Interestingly, positive ELISA results in previously diagnosed (PD) RA were more common than newly diagnosed (ND) RA patients (P < 0.05).; The findings showed a higher frequency of MAP and its antibodies in the RA patients than in the controls. This data indicated MAP as one of RA's predisposing factors. Also, this first report implies the high positivity of MAP in Iranian RA patients.