Objective: To identify predictors of short- and long-term outcomes in acute myelitis (AM).
Design: First episodes of AM were retrospectively identified in a single institution. Information regarding demographics, clinical status, laboratory workup, magnetic resonance imaging of the spine and brain, and electrophysiological assessment was collected. Tau, 14-3-3 protein, and cystatin C levels were assessed de novo in stored cerebrospinal fluid samples.
Setting: A neurological department database. Patients Fifty-three patients with a first episode of AM.
Main outcome measures: The prognostic value of all variables was analyzed for the following outcomes: recovery from the initial event, symptom recurrence, conversion to multiple sclerosis (MS), and long-term disability.
Results: Median follow-up was 6.2 years. Six patients (11%) remained monophasic; 5 (9%) developed recurrent myelitis; and 42 (79%) underwent conversion to MS. Sensory level absence, no sphincter involvement, abnormal magnetic resonance imaging findings in the brain, spinal cord lesions shorter than 3 vertebral segments, and abnormal somatosensory evoked potentials predicted MS conversion. Fifteen of 32 patients with pyramidal dysfunction at onset (47%) and 17 of 43 with relapses during follow-up (40%) had significant disability at the last visit compared with 2 of 21 patients without pyramidal manifestations (10%) and none of the patients without exacerbations (P = .006 and P = .02, respectively). In 11 patients with exacerbations, we observed a significant correlation between cerebrospinal fluid levels of cystatin C and the degree of neurological disability at the last visit (Spearman rho = 0.69; P = .03).
Conclusions: For patients with first-episode AM, the conversion rate to MS is high. Motor dysfunction at onset and relapse occurrence are associated with worse outcome. Cerebrospinal fluid levels of cystatin C may prove useful for predicting the prognosis of such patients.