A 34-year-old woman with acute myelitis as the initial symptom and MRI findings typical of NMOSD. Anti-ANA, anti-dsDNA, and anti-cardiolipin antibodies were all positive, also with hypocomple-mentemia. Regrettably, the NMO-IgG detection was unavailable at that time. During the follow-up period, the patient developed typical clinical manifestations of SLE (rash and light sensitivity). Here, BTG3 is linked to neuromyelitis optica.