A Multi-Center Retrospective Cohort Study of Neurosarcoidosis Myelitis: Current Observations and Future Directions

The optimal treatment for neurosarcoidosis myelitis is uncertain. We characterize incident neurosarcoidosis myelitis and assess treatment response by MRI and clinical scales.

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.

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 A₁), 36 (17.8%) received corticosteroids < 4 weeks (B₁), 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 (A₁ 27/106 (25.5%), B₁ 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).

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.