Spinal cord multiple sclerosis and devic neuromyelitis optica in children.

We read with interest the article by Glasier et al, “Clinical, Neurodiagnostic, and MR Findings in Children with Spinal and Brain Stem Multiple Sclerosis” (1). In this study, five of seven children with spinal multiple sclerosis (MS) had lesions that extended over three or more segments with concomitant cord swelling. This differs from our experience as well as that of previous authors. Typical plaques in the spinal cord are usually small, extend over fewer than two vertebral segments, involve less than one half the cross-sectional area of the spinal cord, and usually do not show cord enlargement (2–4). We acknowledge that MS may present differently in children. It is known that acute MS plaques in children may be large and can simulate a brain tumor on magnetic resonance (MR) (5). However, we postulate that many of the cases described by Glasier et al may actually represent Devic syndrome. In their series, four of the five patients with swollen spinal cords and lesions extending for multiple segments presented with or subsequently developed optic neuritis. In two of these patients, the initial MR of the brain was negative. The lesions described in the spinal cords of these four patients bear a striking resemblance to a subacute necrotic myelopathy that is the characteristic spinal lesion in Devic neuromyelitis optica. The clinical syndrome is regarded as a form of MS or as a separate neurologic syndrome. Devic neuromyelitis optica is characterized by an extensive necrotizing myelopathy, associated with “optic neuritis” usually occurring before the onset of the myelopathy. Brain MR studies typically are normal initially, without evidence of typical MS plaques. Oligoclonal bands also are typically negative (4, 6). In conclusion, the diagnosis of MS will continue to be a dilemma in children. However, we feel that the features described on the spinal MR studies in Glasier’s article are most compatible with a necrotic myelopathy as opposed to atypical demyelinating plaques of multiple sclerosis. Very little has been written about Devic neuromyelitis optica in the literature, and its exact classification remains unclear. It also is not known whether there is an increased incidence of Devic neuromyelitis optica in children. We were very intrigued by the series presented by Glasier et al and expect it will elicit further study about MS and its related conditions in children.