Neuromyelitis optica spectrum disorder mimicking extensive leukodystrophy

Area of Science:

• Neurology
• Neuroimmunology
• Radiology

Background:

• Neuromyelitis Optica Spectrum Disorders (NMO-SD) are autoimmune conditions affecting the central nervous system.
• Historically, brain Magnetic Resonance Imaging (MRI) in NMO-SD was often considered normal, but typical lesion patterns are now recognized.
• The comprehensive MRI pattern for NMO-SD is still evolving.

Observation:

• A 50-year-old woman with a long-standing diagnosis of anti-Aquaporin-4 antibody-positive (anti-AQP4+) NMO-SD presented with unusual brain MRI findings.
• The observed brain MRI showed extensive white matter lesions (EWML).
• These EWML mimicked the appearance of leukodystrophy, a group of genetic white matter disorders.

Findings:

• The case highlights an atypical presentation of NMO-SD characterized by extensive white matter lesions.
• These lesions were significant enough to be mistaken for leukodystrophy on initial radiological assessment.
• This challenges the previously held notion of typically normal or less extensive brain MRI findings in NMO-SD.

Implications:

• The findings suggest that extensive white matter lesions (EWML) should be considered as a potential brain MRI manifestation in patients with NMO-SD.
• This broadens the spectrum of neuroimaging findings associated with NMO-SD.
• Recognizing EWML as a possible NMO-SD presentation may aid in earlier and more accurate diagnosis, especially in anti-AQP4+ individuals.