HP and rheumatoid arthritis: For instance, IL-17 was observed in rheumatoid arthritis (RA) and osteoarthritis synovial fluids.36 In our study, IL-17A showed a significant increase in Hp+ patients, which is in line with the results reported by Arachchi et al in 2017.37 Increased expression of the IL-17 gene (compared to Hp-) has been reported in the H. pylori-infected biopsies.38 Moreover, high levels of IL-17 in the gastric mucus have been reported at the infection site.