Basic Neuroscience · Neuropharmacology
MS vs NMOSD vs MOGAD
Distinguishing the three main inflammatory demyelinating diseases. Confirm AQP4-IgG and MOG-IgG serostatus (cell-based assay) before long-term treatment — misdiagnosis leads to harmful or ineffective therapy.
| Feature | Multiple Sclerosis | NMOSD (AQP4-IgG) | MOGAD (MOG-IgG) |
|---|---|---|---|
| Target antigen | None identified (T-cell–mediated CNS demyelination) | AQP4 water channel on astrocytes | MOG on the oligodendrocyte / myelin surface |
| Demographics | Young adults; F:M ~3:1 | Median ~40 y; F:M up to ~9:1; more common in non-white populations | All ages incl. children; F ≈ M |
| Optic neuritis | Usually unilateral, mild–moderate | Severe, may be bilateral; posterior/chiasmal; poor recovery | Often bilateral, painful, with disc edema; usually good recovery |
| Myelitis | Short-segment, partial | LETM ≥3 vertebral segments, central cord | LETM, often conus/cauda; H-sign on axial |
| Other hallmark attacks | Brainstem/cerebellar, cognitive | Area postrema (intractable nausea/vomiting/hiccups), diencephalic, narcolepsy | ADEM (esp. children); cortical encephalitis with seizures (FLAMES) |
| Brain MRI | Periventricular ovoid (Dawson fingers), juxtacortical, infratentorial | Periependymal (around 3rd/4th ventricle & area postrema), diencephalic | Fluffy / ill-defined, ADEM-like, often resolves; cortical FLAIR-hyperintensity |
| CSF oligoclonal bands | Positive ~85–95% | Usually negative (<20%) | Usually negative |
| Serology | No specific antibody | AQP4-IgG (cell-based assay) | MOG-IgG (cell-based assay); low/transient titers can be false-positive |
| Course | Relapsing → secondary progressive; progression independent of relapses | Relapsing; no progressive phase — disability is attack-driven | Monophasic or relapsing; disability attack-related |
| Attack recovery | Usually moderate | Often severe / incomplete | Often good |
| Acute treatment | IV methylprednisolone ± PLEX | IV steroids + early PLEX | IV steroids (steroid-responsive/dependent) ± IVIG/PLEX |
| Maintenance | DMTs (interferons → anti-CD20; see MS DMT sheet) | Eculizumab, ravulizumab, inebilizumab, satralizumab (FDA); rituximab | Off-label: rituximab (less reliable), IVIG, MMF, azathioprine — no FDA-approved therapy |
| ⚠ Key pitfall | — | MS DMTs (IFN-β, natalizumab, fingolimod) WORSEN NMOSD | Don’t over-call on a low/transient MOG titer; re-test if uncertain |
Bottom line: MS — OCB-positive, short lesions, progressive course, treat with DMTs. NMOSD — AQP4-IgG, LETM & area postrema, severe attacks, treat with complement/IL-6/anti-CD20 (never MS DMTs). MOGAD — MOG-IgG, ADEM/bilateral ON, steroid-responsive, often monophasic; no approved therapy.
Neuro-Pharmacology — NeurologyResident.Net by Ahmed Koriesh