Pure spinal multiple sclerosis: A case series of a possible new entity.

Background: Recent literature describes a condition similar to multiple sclerosis (MS) but with demyelinating lesions limited to the spinal cord. This condition, referred to as "pure spinal" MS, might benefit from disease-modifying treatment (DMT).

Methods: We screened the medical records of approximately 8000 patients with demyelinating diseases at the Isfahan MS clinic in Iran. Criteria for inclusion in the case series were adults with a demyelinating disease limited to the spinal cord, positive oligoclonal IgG bands in cerebrospinal fluid (CSF), and negative results for other potential diagnoses.

Results: Seven people with pure spinal MS were identified (all women, mean age [SD]: 40.14 [6.17] years at the first visit, mean follow-up duration [SD]: 98 [39.41] months). Two had a family history of conventional MS in their siblings. All patients exhibited lower limb weakness and tested negative for anti-MOG and anti-AQP4 antibodies. They experienced relapsing-remitting partial myelitis, with new spinal cord lesions on MRI but no extraspinal CNS lesions. DMT significantly reduced relapse rates in all patients, and two showed no increase in EDSS scores.

Conclusion: Pure spinal MS might be an atypical form of MS. Those affected may benefit from DMT; therefore, further investigation and consideration in the upcoming revisions of the McDonald criteria are recommended.