Purpose of review: We reviewed present topics on neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein (MOG)-antibody-associated disease (MOGAD).
Recent findings: The number of NMOSD-related publications have increased year by year after the discovery of aquaporin 4 (AQP4)-antibody, and those on MOGAD started to surge since 2012-2013. Recent clinic-epidemiological surveys in NMOSD suggest that some racial differences in the prevalence and the clinical course. At present, experts feel the 2015 diagnostic criteria of AQP4-antibody-seronegative NMOSD should be revised. Randomized controlled trials of monoclonal antibodies in NMOSD have demonstrated a significant risk reduction of relapse, especially in AQP4-antibody-positive cases. Meanwhile, the efficacy in seronegative NMOSD was unclear. MOGAD can show NMO and other clinical phenotypes, but the clinical manifestations and frequencies are different in children and adults. One pathological study has suggested that MOGAD is distinct from AQP4-antibody-positive NMOSD, but may share some features with multiple sclerosis and acute disseminated encephalomyelitis. Immunosuppressive therapy can reduce relapse in MOGAD, but, unlike AQP4-antibody-positive NMOSD, some MOGAD patients treated with rituximab experience relapses despite a complete B-cell depletion.
Summary: Our understanding and therapy of AQP4-antibody-positive NMOSD has made a significant progress, and recent research has identified challenges in seronegative NMOSD and MOGAD.