Bacteriological and Molecular Assessment of Staphylococcal Enterotoxin E in the Blood of Patients With Rheumatoid Arthritis

BACKGROUND: Rheumatoid arthritis (RA) is the most common chronic inflammatory disease of unknown etiology. In this regard, the role of bacterial superantigens (as an effective agent) were considered. OBJECTIVES: This study aimed to assess staphylococcal enterotoxin E in the blood of patients with rheumatoid arthritis. PATIENTS AND METHODS: A total of 83 blood samples of patients with RA were studied. All of patient's blood samples have been cultured. Polymerase chain reaction (PCR) and ELISA methods have been used to assess the existence of staphylococcal enterotoxin E (entE). The data were analyzed through descriptive statistics. RESULTS: During this study and after sequential sub cultures, only 5 bacterial strains were isolated. Based on the results of biochemical tests, just one case was detected as Staphylococcus aureus. The result of molecular diagnosis of enterotoxin E gene was 13.25%. The results of ELISA were 40.96% positive for staphylococcal enterotoxin E. CONCLUSIONS: In this study, staphylococcal enterotoxin E (superantigen E) was detected in the blood of patients with RA, but its origin is unknown, because no staphylococcus enterotoxin E producer was isolated. This finding could provide a good model for the diagnosis and treatment of RA. However, the results of this study have shown some evidence regarding endogenous origin of involved superantigens in patients with rheumatoid arthritis.