To determine the age and sex distribution of Myelin oligodendrocyte glycoprotein (MOG)-IgG seropositive and aquaporin-4 (AQP4)-IgG seropositive patients versus those testing negative.
MOG-IgG is a biomarker of MOG-antibody-associated-disease (MOGAD), a distinct central nervous system demyelinating disease with overlapping clinical features with AQP4-IgG-seropositive-neuromyelitis-optica-spectrum-disorders (AQP4+NMOSD). Knowledge of age and sex distribution from large cohorts tested for MOG-IgG and AQP4-IgG can provide useful epidemiology data to guide allocation of resources and healthcare delivery.
This is a retrospective laboratory-based study utilizing the Mayo Clinic neuroimmunology laboratory data on serum testing of MOG-IgG with live cell-based assay (2017-2022) and AQP4-IgG with fixed or live cell-based assay (2007-2021). Age, sex, and antibody titers were evaluated.
Of 96,373 patients’ sera tested for MOG-IgG, 7,367 (7.6%) were positive. Patients seropositive for MOG-IgG were younger than MOG-IgG seronegative patients (median age 34 [IQR 17-49] vs 42 [30-55] years, respectively; p<0.001). Among MOG-IgG seropositive patients, 1,167 (15.8%) were pediatric (aged <12 years), and 735 (10%) 12-17 years and 475 (6.5%) were elderly (aged ≥65 years). MOG-IgG seropositives had a female-to-male ratio of 1.6:1 while MOG-IgG seronegatives had a ratio of 2:1. The median MOG-IgG titer was 1:100 (IQR 1:40-1:100). Higher serum titers (≥1:1,000) were most frequent in pediatrics (42.8%) versus other groups (p<0.001).
Of 145,418 patients’ sera tested for AQP4-IgG, 5,505 (3.8%) were positive. The median age of AQP4-IgG seropositive and seronegative patients was 48 (IQR 33-60) and 42 (IQR 30-54) years, respectively; p<0.001. The female-to-male ratio in AQP4-IgG seropositives was 6.5:1 and greater than AQP4-IgG seronegatives (2:1) (p<0.001). The median AQP4-IgG serum titer was 1:1,000 (IQR 1:100-1:10,000).
This large dataset shows the predilection of pediatric patients for both MOG-IgG positivity and higher titers while also revealing a slight female predominance. In comparison, AQP4-IgG positives were older and had a higher proportion of females.