inflammatorydemyelinating

Inflammatory demyelinating refers to a group of disorders in which immune-mediated inflammation damages the myelin sheath surrounding nerve fibers, primarily in the central nervous system but sometimes involving the peripheral nervous system. The best-known examples include multiple sclerosis, acute disseminated encephalomyelitis, neuromyelitis optica spectrum disorders, and myelin oligodendrocyte glycoprotein antibody-associated disease. The term is descriptive and encompasses several distinct diseases rather than indicating a single condition.

Pathophysiology involves immune mechanisms where autoreactive T and B cells target myelin and, in some conditions, antibodies against specific myelin or astrocyte components drive inflammation and demyelination. This can result in focal or disseminated lesions with variable axonal injury. Distinct entities within this category may be associated with specific antibodies, such as aquaporin-4–IgG in NMOSD or MOG-IgG in MOGAD, while others like classic MS may lack a single defining antibody.

Clinical features vary by disease and site of injury. Common manifestations include optic neuritis, transverse myelitis, brainstem or cerebellar symptoms, and cognitive changes. Acute disseminated encephalomyelitis often presents with a rapid, multifocal neurologic syndrome, frequently following infection or vaccination, particularly in children.

Diagnosis combines clinical history with magnetic resonance imaging, cerebrospinal fluid analysis, and targeted serologic tests for disease-specific antibodies. Imaging typically shows demyelinating lesions in the CNS; CSF may reveal oligoclonal bands or elevated IgG index in some conditions. Testing for AQP4-IgG and MOG-IgG helps distinguish NMOSD and MOGAD from other IDDs.

Treatment focuses on controlling inflammation and preventing relapses. Acute attacks are treated with high-dose corticosteroids, with plasmapheresis or IVIG for refractory cases. Long-term management depends on the underlying diagnosis and may include disease-modifying therapies, immunosuppressants, or targeted biologics. Prognosis varies widely by subtype and response to therapy.