This study was approved by the Mayo Clinic Institutional Review Board.Īll samples were stored at −80☌ at the Mayo Clinic central laboratory. In contrast, the negative predictive value is the percentage of negative test results in patients without an MOG-IgG–like clinical phenotype of all negative test results and is an estimate of how reliably a negative test result rules out the disease. Positive predictive value (PPV) was calculated as the percentage of positive test results in patients with MOG-IgG–like clinical phenotypes of all positive test results and estimates the reliability of a positive test result. Specificity was calculated as the percentage of positive cases in the MS cohort and those with other neurologic presentations inconsistent with an MOG-related clinical phenotype. Sensitivity was calculated as the percentage of positives cases within the MOG-IgG–like clinical phenotype cohort. The control samples were collected from patients with MS (244, selected from the Olmsted County MS population-based cohort), hypergammaglobulinemia (42), and other (17, encephalitis, glioma, Creutzfeldt-Jakob disease, glaucoma). Serum samples from 394 patients and controls were tested: 91 patients were classified as having a MOG-IgG–like clinical phenotype and included ADEM (28), AQP4-IgG seronegative NMO (27, fulfilling Wingerchuk diagnostic criteria for NMO, either 1999 or 2006 ), optic neuritis (21 single, 2 relapsing), or longitudinally extensive transverse myelitis (10 single, 3 recurrent). The study was approved by the Institutional Review Board of Mayo Clinic, Rochester, MN (No. Standard protocol approvals, registrations, and patient consentsĪll patients in our study consented to the use of their medical records for research purposes. Hence, accurate serologic diagnosis is imperative to optimize clinical care.Ī recent review article published in 2017 by key opinion leaders in the field stated that “methods for detecting MOG antibodies have improved substantially, with cell based assays (CBAs) being state of the art.” 1 In this blinded study, 3 different MOG-IgG CBAs from 3 international centers were compared. MOG-IgG also provides important prognostic information. 4, –, 8 Early initiation and prolonged administration of such drugs may prevent relapses and reduce disability accrual, although randomized clinical trials have not yet been undertaken. While MOG antibody has had a checkered past as a biomarker because of a lack of any specific disease association, contemporary methodologies using cell-based assays (CBAs) now define an autoimmune oligodendroglyopathy with a preferential response to immunosuppressants rather than disease-modifying agents (DMA) commonly used in MS. MOG-IgG may be transient or persistent, and its role as a predictor of relapse remains a focus of ongoing study. Attacks may be associated with accumulating neuronal injury and functional impairment.
MOG-IgG–associated IDDs may have a higher prevalence in children and are often relapsing, commonly manifesting as optic neuritis.
1, –, 5 Until their relatively recent discovery, patients with these disorders were commonly misdiagnosed as having multiple sclerosis (MS), yet contemporary findings show that MS, MOG-IgG, and AQP4-IgG–associated IDDs have clinical, radiologic, pathologic, and prognostic differences. There is accumulating evidence that CNS inflammatory demyelinating disorders (IDDs), including forms of neuromyelitis optica (NMO) spectrum disorders, acute disseminated encephalomyelitis (ADEM), optic neuritis (recurrent more than single episode), and transverse myelitis are commonly associated with immunoglobulin G (IgG) targeting aquaporin-4 (AQP4) or myelin oligodendrocyte glycoprotein (MOG).
Glossary ADEM = acute disseminated encephalomyelitis AQP4 = aquaporin-4 CBA = cell-based assay DMA = disease-modifying agent IDD = inflammatory demyelinating disorder IgG = immunoglobulin G IIF = indirect immunofluorescence MOG = myelin oligodendrocyte glycoprotein MS = multiple sclerosis NMO = neuromyelitis optica PPV = positive predictive value