Isolated longitudinal myelitis: a report of six cases

Study design: Retrospective chart review. Objective: To report six patients with isolated longitudinal myelitis (LM). Setting: Outpatients at Multiple Sclerosis Center/Clinic Vanderbilt University Medical Center. Methods: 1. Patients: Patients treated for LM in whom evidence for multiple sclerosis (MS), neuromyelitis optica (NMO) and systemic inflammatory disorders such as systemic lupus erythematosus (SLE) was lacking. 2. Interventions: Clinical, laboratory and imaging data, treatment and outcomes were reviewed. 3. Main Outcome Measures: LM in the absence of optic neuritis, normal or nonspecific brain magnetic resonance imaging (MRI) findings, the absence of NMO antibody. Results: All presented with monophasic myelitis with variable loss of motor, sensory and bowel/bladder functions. MRIs of the brain were normal (five cases), and in the sixth showed a single T2 hyperintense lesion, which was interpreted as an ischemic lesion due to small-vessel disease. MRIs of the spinal cord of all patients showed swelling and T2 hyperintense lesions with patchy contrast enhancement that extended from the cervicomedullary junction to the conus medullaris. Two of these patients received rituximab with clinical benefit. Another patient received one dose of rituximab, developed an allergic reaction, received further treatments with azathioprine and also made a good recovery. In one patient, approval for rituximab was obtained several months after the inflammation had subsided, and she has shown only a minimal improvement. The two patients who did not receive rituximab made no significant recovery from their maximal neurological deficits. Conclusions: Isolated LM may be a new clinical syndrome, or a variant of NMO.