Leila Masoori - Department of Laboratory Sciences, School of Allied Medical Sciences, Lorestan University of Medical Sciences, Khorramabad, Iran
Morteza Molazadeh - Quality Management, Giti Tajhiz Teb, Tehran, Iran
Nahid Rezaei - Department of Laboratory Sciences, School of Allied Medical Sciences, Lorestan University of Medical Sciences, Khorramabad, Iran
Somaye Alizadeh - Medical Education Development Center, North Khorasan University of Medical Sciences, Bojnurd, Iran
Hamid Hassanpour - Department of Parasitology and Mycology, School of Allied Medical Sciences, Ilam University of Medical Sciences, Ilam, Iran
Alireza Badirzadeh - Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran

Background: Toxoplasma gondii (T. gondii) is an intracellular protozoan parasite capable of infecting approximately one-third of the world human population. In this study, the seroprevalence of Toxoplasma gondii (T. gondii) antibodies in Iranian patients with rheumatoid arthritis was investigated, given the lack of information on the magnitude of toxoplasmosis in these patients.Methods: The serum was collected from patients with rheumatoid arthritis (n = ۹۳) and a healthy control group (n = ۹۳) from central parts of Iran to investigate the prevalence of anti-T. gondii IgG and IgM antibodies.Results: Anti-T. gondii IgG was detected among ۷۶ of ۹۳ patients with rheumatoid arthritis (۸۱.۷۲%) versus ۳۷ of ۹۳ healthy control group (۳۹.۸۰%), and it was higher among patients with rheumatoid arthritis than controls. The seroprevalence of anti-T. gondii IgM was significantly higher in patients with rheumatoid arthritis (۳۶ of ۹۳; ۳۸.۷۰%) compared to the healthy control group (۲ of ۹۳; ۲.۱%). Demographic variables (age and sex) did not have significant correlations in patients with rheumatoid arthritis who were positive for T. gondii infection.Conclusion: The findings of the present study provide efficient evidence that confirm the association between toxoplasmosis and development of rheumatoid arthritis, suggesting that Toxoplasma may contribute to the rheumatoid arthritis pathogenesis.

Toxoplasma gondii, Autoimmunity, Rheumatoid Arthritis, Iran, Immune system