Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an autoimmune disease of the central nervous system currently recognised as a separate entity from seropositive neuromyelitis optica spectrum disorder and multiple sclerosis (MS). Although diagnosis recommendations for MOGAD have been proposed (1), currently there are no formal consensus diagnostic criteria. Recently, an international panel of experts (2) have developed MOGAD diagnostic criteria for adult and paediatric age groups, requiring the presence of three main criteria: 1) one of six core clinical demyelinating events (optic neuritis, myelitis, acute disseminated encephalomyelitis, cerebral monofocal or polyfocal deficits, brainstem or cerebellar deficits, cerebral cortical encephalitis); 2) a positive MOG-IgG test; 3) exclusion of alternative diagnoses. For a clear positive test performed having established criteria 1) and 3), the diagnosis is ascertained. However, a low positive, positive without reported titre or a negative serum testing with CSF positivity require the support of clinical or MRI features.
The panel underlines the importance of MOG-IgG testing in an appropriate clinical context in order to enhance the positive predictive value of the test. False positive diagnoses may result from MOG-IgG seropositivity at lower titres in other demyelinating diseases, such as MS (up to 2.5%).
Live cell-based assays are more sensitive and specific than fixed cell-based assays, which are commercially used. The panel recommend that test reports provide qualitative and semi-quantitative results with reference values.
These proposed diagnostic criteria may improve identification of MOGAD and enable progress by refining the design of clinical trials targeting therapeutics or predictors of disease course.
Key points
- MOGAD has been recognised as a distinct demyelinating disease of the central nervous system, for which diagnostic criteria are warranted.
- MOG-IgG serum testing should only be performed when clinical and imaging features are suggestive of MOGAD, so as to avoid false positive results.
- Live cell-based assays that use full-length human MOG should be used to detect MOG-IgG. Fixed cell-based assays are a less sensitive and specific alternative.
- Serum MOG-IgG reports should include qualitative and semi-quantitative results.
- While these proposed criteria require validation in further studies, they are a step forward to identifying and managing MOGAD.
References
- Jarius S., Paul F., Aktas O. et al. MOG encephalomyelitis : international recommendations on diagnosis and antibody testing. J Neuroinflammation 2018; 15(1): 134. https://pubmed.ncbi.nlm.nih.gov/29724224/
- Banwell B., Bennett J. L., Marignier R. et al. Diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disease: International MOGAD Panel proposed criteria. Lancet Neurol 2023; P246-257. https://pubmed.ncbi.nlm.nih.gov/36706773/
Publish on behalf of the Scientific Panel Multiple Sclerosis