Myelin Oligodendrocyte Glycoprotein and Aquaporin 4 Antibody Related Diseases In Childhood: A Nationwide Multicentric Retrospective Study

Objective: Knowledge about neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) has been evolving. MOGAD usually presents with acute disseminated encephalomyelitis (ADEM), optic neuritis (ON) and transverse myelitis (TM) and NMOSD, with TM, ON and limited forms of the disease. We assessed clinical aspects, response to treatment, outcome of these diseases. Methods: Data obtained from hospital registry systems of 13 participating centers were classified, and results displayed by descriptive statistics. Results: There were 112 patients (70 F, 63%): 79 (70%) MOGAD (MOG IgG-positive) and 33 (30%) NMOSD (aquaporin-4 IgG-positive and double negative), mean age 11.5±4.6 in MOGAD, 14.1±4.9 in NMOSD. Course was polyphasic in 33/79 (42%) MOGAD, with annualized relapse rate (ARR) 1.01±0.79 (0.3-4, median 0.8), in 17/33 (51.5%) NMOSD with ARR 0.84±0.61 (0.2-2, median 0.6). MOGAD mostly presented with ADEM (23/46, 50%) and NMOSD, with ON and/or TM (16/17, 94%). Aquaporin 4 antibody was positive in 16/33 (48.5%) of NMOSD patients. Besides typical ADEM and ON, magnetic resonance imaging (MRI) could show atypical findings: meningoencephalitis-, leukodystrophy-, or MS-like lesions in MOGAD. Sequelae, mostly visual, were observed in 21.5% MOGAD and 42.5% NMOSD cases. Frequent maintenance treatments were intravenous immunoglobulin (IVIg) in MOGAD (17/79, 21.5%), azathioprine in NMOSD (17/33, 51%). Remission was achieved with IVIg in 6/13 MOGAD and rituximab in 3/5 NMOSD. Conclusion: MOGAD was twice as frequent as NMOSD in our cohort. NMOSD patients were older. As treatment and course vary between diagnostic groups, differences in clinical presentation and outcome may assist correct classification.