Majed, Masoud

ABSTRACT Objective The optimal treatment for neurosarcoidosis myelitis is uncertain. We characterize incident neurosarcoidosis myelitis and assess treatment response by MRI and clinical scales. Methods Incident probable or definite neurosarcoidosis myelitis in adults was retrospectively identified from 13 academic medical centers. Cases were analyzed by initial treatment. The primary outcome was T1 post‐contrast gadolinium enhancement resolution at 6 months post‐treatment. Secondary outcomes were changes in modified Rankin scale (mRS) and Expanded Disability Status Scale (EDSS) from nadir to final follow‐up. Results Two hundred two patients were identified (median diagnosis age: 47 years (IQR 39–55); male: female 1.3:1). Median nadir mRS and EDSS were 2 (IQR 2–3) and 4 (IQR 2.5–6). At initial treatment, 129 (63.9%) received prolonged corticosteroids ≥ 4 weeks (group A 1 ), 36 (17.8%) received corticosteroids < 4 weeks (B 1 ), 21 (10.4%) received corticosteroids plus sarcoidosis‐directed immunosuppressant (E), and 16 (7.9%) received corticosteroids plus non‐sarcoidosis‐directed agents (F). In 167 cases with sufficient imaging, there were no significant differences in contrast enhancement resolution at 6 months (A 1 27/106 (25.5%), B 1 9/28 (32.1%), E 5/19 (26.3%), F 5/14 (35.7%); Fisher's exact p = 0.76). There were no significant differences in changes in mRS or EDSS among treatment groups (Kruskal–Wallis p = 0.69 and 0.63, respectively) after median follow‐up of 46.5 months (IQR 18–91.3). Interpretation Different initial immunosuppression strategies did not correlate with MRI contrast enhancement resolution at 6 months or clinical scales (mRS, EDSS). However, conclusions are limited by retrospective design, imbalanced cohorts, and insensitivity of binary MRI outcomes and available clinical scales for treatment response in neurosarcoidosis.

Objective The aim of this study was to assess the diagnostic utility of cerebrospinal fluid (CSF) myelin oligodendrocyte glycoprotein antibodies (MOG‐IgG) testing. Methods We retrospectively identified patients for CSF MOG‐IgG testing from January 1, 1996, to May 1, 2023, at Mayo Clinic and other medical centers that sent CSF MOG‐IgG for testing including: controls, 282; serum MOG‐IgG positive MOG antibody‐associated disease (MOGAD), 74; serum MOG‐IgG negative high‐risk phenotypes, 73; serum false positive MOG‐IgG with alternative diagnoses, 18. A live cell‐based assay assessed CSF MOG‐IgG positivity (IgG‐binding‐index [IBI], ≥2.5) using multiple anti‐human secondary antibodies and end‐titers were calculated if sufficient sample volume. Correlation of CSF MOG‐IgG IBI and titer was assessed. Results The pan‐IgG Fc‐specific secondary was optimal, yielding CSF MOG‐IgG sensitivity of 90% and specificity of 98% (Youden's index 0.88). CSF MOG‐IgG was positive in: 4/282 (1.4%) controls; 66/74 (89%) serum MOG‐IgG positive MOGAD patients; and 9/73 (12%) serum MOG‐IgG negative patients with high‐risk phenotypes. Serum negative but CSF positive MOG‐IgG accounted for 9/83 (11%) MOGAD patients, and all fulfilled 2023 MOGAD diagnostic criteria. Subgroup analysis of serum MOG‐IgG low‐positives revealed CSF MOG‐IgG positivity more in MOGAD (13/16[81%]) than other diseases with false positive serum MOG‐IgG (3/15[20%]) ( p = 0.01). CSF MOG‐IgG IBI and CSF MOG‐IgG titer (both available in 29 samples) were correlated (Spearman's r = 0.64, p < 0.001). Interpretation CSF MOG‐IgG testing has diagnostic utility in patients with a suspicious phenotype but negative serum MOG‐IgG, and those with low positive serum MOG‐IgG results and diagnostic uncertainty. These findings support a role for CSF MOG‐IgG testing in the appropriate clinical setting. ANN NEUROL 2024;96:34–45