Tajfirouz, Deena

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.

Background Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and multiple sclerosis (MS) have both overlapping and distinct MRI lesion features, which vary with imaging timing. This study identified distinguishing MRI characteristics using paired MRIs at clinical attack and remission. Methods We retrospectively identified Mayo Clinic patients with MOGAD and MS that: (1) fulfilled respective diagnostic criteria; (2) had paired attack (≤30 days) and remission MRI scans (≥12 months) without interval attacks. MRIs were compared between groups for key features. Results We included 43 patients with MOGAD (median age 31 years (range, 3–67); 63% female) and 49 patients with MS (median age 39 years (range, 17–65); 65% female). Resolution of at least one T2-lesion differentiated MOGAD from MS (sensitivity, (95% CI 77% to 100%), specificity, (95% CI 86% to 99%); Youden’s index (YI)=0.90). Resolution of at least two T2-lesions indicated MOGAD (sensitivity 62% (95% CI 41% to 79%); specificity, 100% (95% CI 94% to 100%); YI=0.62). MOGAD patients were more likely to have normal MRI scans at follow-up compared with MS (brain 14/44 (32%) vs 0/60 (0%), p<0.001; spine 21/27 (78%) vs 7/36 (19%), p<0.001). In addition, the presence of T1-hypointense, ovoid periventricular T2, and enhancing lesions were more common in MS versus MOGAD at attack and remission and in the spine, longitudinally extensive T2 lesions were more common in MOGAD attacks (8/27 (30%)). Conclusion Paired MRI at attack and remission revealed distinctive characteristics of MOGAD and MS, with greater diagnostic value at remission driven by the discriminating power of T2-lesion resolution. In MOGAD patients with initial parenchymal involvement, a 1-year follow-up MRI may aid diagnosis and serve as a new baseline.

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.