Chodnicki, Kevin D.

Seronegative neuromyelitis optica spectrum disorder (NMOSD) is a diagnostic challenge. This study aimed to characterize misapplication of the 2015 international criteria for seronegative NMOSD. We reviewed 35 consecutive seronegative NMOSD referrals to a tertiary center. Two (6%) met formal criteria, and 2 (6%) were clinically suspected of NMOSD without fulfilling radiologic supportive criteria. Alternative diagnoses were common including multiple sclerosis (37%), optic neuritis (14%), functional neurologic disorder (11%), and other (38%). Immunosuppression with rituximab was used in 3 of 4 patients with functional neurologic disorder. Misapplication of the 2015 criteria is common, and alternative explanations in seronegative NMOSD patients should be strongly considered.

Increased intracranial pressure (ICP) is increasingly recognized in myelin oligodendrocyte glycoprotein antibody-associated disease but has not been systematically explored in other demyelinating conditions. This cross-sectional study examines the features of raised ICP in aquaporin-4-IgG-positive neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS). Lumbar puncture opening pressure (OP) done within 30 days of an attack was identified in 41 NMOSD patients and 37 MS patients. Raised OP was present in 7 (17.1%) NMOSD patients and 4 (10.8%) MS patients who were largely asymptomatic, partially explained by obesity, and did not require ICP lowering medications beyond acute treatment with corticosteroids.