In this context, we performed a retrospective study of patients with rheumatologic disease and myelitis who were evaluated at our center over the past 5 years, to determine clinicoradiologic and serologic overlap with AQP4-IgG seropositive NMOSD and MOGAD and further characterize cases of “double-seronegative” myelitis. Here, AQP4 is linked to myelitis.