Association Between Helicobacter Pylori Infection and Seronegative Neuromyelitis Optica Spectrum Disorder

Background: Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune demyelinating disease in the central nervous system. Association between NMOSD and Helicobacter pylori (H. pylori) infection has been investigated, but few studies have assessed the relationship between H. pylori and seronegative AQP4-Ab NMOSD. Objectives: This study aimed to survey the association between H. pylori infection and NMOSD patients with seronegative AQP4-Ab status, as well as the possible relationship between the presence of H. pylori and clinical characteristics. Materials & Methods: This cross-sectional study was carried out in Kashani Hospital affiliated with the Isfahan University of Medical Sciences, Isfahan, Iran, from October 2017 to May 2019. A total of 35 consecutive seronegative AQP4-Ab NMOSD patients and 37 sex and age-matched healthy controls participated in the study. Demographic and clinical characteristics were obtained from all participants. We assessed participants’ seroprevalence of IgG and IgM antibodies against H. pylori. The Association of H. pylori with NMOSD was determined. Results: The frequency of IgG and IgM Ab H. pylori seropositivity in NMOSD patients was 22.9% and 40.0%, respectively. Among HC, 11(29.7%) and 20(54.1%) were positive for IgG and IgM Ab H. pylori. Although the rate of H. pylori IgG (OR=0.700, 95%, CI=0.243, 2.017, P=0.420) and IgM Ab (OR=0.567, 95%, CI=0.222, 1.444, P=0.233) seropositivity in NMOSD were lower than NMOSD, these differences were not statistically different. No clinical variables associated with H. pylori IgG and IgM seropositivity infection seropositivity. Conclusion: These findings show that possibly there is no relationship between H. pylori infection and seronegative AQP4-Ab NMOSD.