Multiple sclerosis, solitary sclerosis or something else?

BACKGROUND: Inflammatory demyelinating diseases of the central nervous system represent a wide spectrum of entities and their classification cannot currently be regarded complete. OBJECTIVE: Our aim is to describe a series of patients presenting with progressive myelopathy associated to a single demyelinating lesion of the spinal cord. METHODS: We identified the patients affected by chronic progressive spinal cord dysfunction related to a single spinal cord lesion not satisfying the diagnostic criteria for any of the currently defined diseases. RESULTS: Seven females and one male were included. The median age at onset of symptoms was 53 years (range 42-68) and the median follow-up was 8 years (range 5-12). Brain and spinal magnetic resonance imaging (MRI) scans detected only one single, circumscribed, T2 hyperintense, non-longitudinally extensive lesion at level of cervico-medullary junction or cervical cord, in the absence of Gadolinium enhancement or swelling. Cerebrospinal fluid (CSF) examination displayed neither oligoclonal bands nor raised IgG index. A response to immunosuppressive agents was observed in some of the patients. Serial control brain and spinal MRI did not reveal accumulation of new lesions. CONCLUSION: New entities or variants should be included among the inflammatory demyelinating diseases of the central nervous system, and their characterization may have relevant prognostic and treatment implications.