Anti-myelin Oligodendrocyte Glycoprotein in Aquaporin-4 Negative Neuromyelitis Optica Spectrum Disorder

Background: The absence of Aquaporin-4 Antibody (AQP4-Ab) in a fraction of the Neuromyelitis Optica Spectrum Disorder (NMOSD) patients has led to a search for other serologic markers. Myelin Oligodendrocyte Glycoprotein (MOG) is a protein component of the myelin sheets encapsulating the neural fibers. Objectives: We aimed to compare the presence and levels of anti-MOG (Ig-G) in a group of seronegative NMOSD patients with a healthy control group. Materials & Methods: In this cross-sectional study, 30 NMOSD patients with negative AQP-Ab status, who were referred to the Neurology Clinic of Kashani University Hospital in Isfahan City, Iran, from March 2015 to March 2016, and 26 healthy controls were consecutively recruited. Their baseline demographic and clinical data were recorded. Serum anti-MOG levels were measured in both groups. The obtained data were analyzed using the Student t-test, Mann-Whitney U, and Chisquare test in SPSS V. 18. Results: The anti-MOG test results were statistically higher in patients (n=12, 37.5%) compared to controls (n=0, 0%) (P<0.0001). The level of anti-MOG in Healthy Control (HC) was higher compared to patients with negative anti-MOG (P<0.0001) and was lower than patients with positive anti-MOG (P<0.0001). Conclusion: Our study showed that nearly one-third of seronegative NMOSD patients were positive for MOG-Ab. Further studies are needed to assess the characteristics and outcome of these patients.