Leptomeningeal and Intraparenchymal Blood Barrier Disruption in a MOG-IgG-Positive Patient.

Background: Recently, pathogenic serum immunoglobulin G (IgG) autoantibodies to myelin oligodendrocyte glycoprotein (MOG) have been detected in a subgroup of patients with central nervous system (CNS) demyelination, including in patients with myelitis. Relatively little is known so far about leptomeningeal involvement in MOG-IgG-positive myelitis.

Findings: We report the case of a 30-year-old previously healthy woman presenting with longitudinally extensive transverse myelitis and tetraparesis, in whom both the leptomeningeal barrier and the blood-brain barrier (BBB) were altered, as demonstrated by gadolinium-enhanced MRI during relapse. Blood samples taken at onset and four years later were retrospectively found positive for MOG-IgG.

Conclusion: Our findings demonstrate that spinal leptomeningeal enhancement (LME) can occur in MOG-IgG-positive encephalomyelitis (EM) and may accompany intraparenchymal BBB breakdown.