The American Academy of Neurology (AAN) has published new guidelines on the diagnosis and treatment of transverse myelitis.

The writing group for the new report, from the Therapeutics and Technology Assessment Subcommittee of the AAN, focused on making evidence-based recommendations, but the evidence for many questions was thin.

"There's a glaring lack of prospective well-designed studies, but the reason for that is pretty obvious: it's a rare disorder," first author Thomas F. Scott, MD, professor of neurology at Drexel University College of Medicine in Pittsburgh, Pennsylvania, told Medscape Medical News. "We really think we need multicenter work to get further with that."

The document, which was also endorsed by the Consortium of MS Centers, was published online December 7 and in the December 13 print issue of Neurology.

Important Changes

Transverse myelitis is an inflammatory lesion of the spinal cord with an incidence of one severe case and eight mild cases per million per year, the authors note. The new recommendations are based on a review of the published literature from 1966 to March 2009, with an evidence-based classification of relevant articles.

Dr. Scott pointed to important changes in the new document: a level B recommendation that neuromyelitis optica (NMO)–immunoglobulin G antibodies should be considered useful to determine the cause of transverse myelitis in patients presenting with features of acute complete transverse myelitis, and that the presence of these antibodies, specifically aquaporin-4-specific antibodies, should be considered useful in determining whether there is an increased risk for recurrence.

NMO antibodies have been "blessed" in the new document as an important test, Dr. Scott said, "because transverse myelitis is somewhat of a broad syndrome, rather than a specific disease."

It is still a level C recommendation, but in terms of treatment, the writing committee has recommended that plasma exchange be considered for patients with transverse myelitis who fail to improve after treatment with corticosteroids.

Although there was only one prospective study of this intervention, Dr. Scott notes, it was well-performed and positive, making it possible to endorse plasmapheresis for those not responding to corticosteroids, which themselves "are empiric therapy, which everybody uses but is not very well proven," Dr. Scott said.

Another treatment option endorsed on the basis of accumulating evidence is rituximab, with a level C recommendation that it may be considered in patients with transverse myelitis resulting from NMO, to decrease the number of relapses.

Other level C recommendations include:

In suspected transverse myelitis cases, a distinction between acute partial transverse myelitis may be considered useful to determine etiology and risk for relapse, which is more common with acute partial transverse myelitis. "I particularly like that we have also blessed the language of acute partial myelitis vs acute complete transverse myelitis, because that involves a lot of my own personal research, but that may be biased," Dr. Scott points out wryly.

• Age and sex may be considered useful to determine etiology in patients presenting with transverse myelitis syndrome, with spinal infarcts seen more often in older patients, and more female than male patients having transverse myelitis resulting from multiple sclerosis (MS).
• Brain magnetic resonance imaging characteristics consistent with those of MS may be considered useful to predict conversion to MS after a first partial transverse myelitis episode.
• Longer spinal lesions extending over 3 vertebral segments may be considered useful in determining NMO vs MS.
• Finally, cerebrospinal fluid examination for cells and oligoclonal bands may be considered useful to determine the cause of the transverse myelitis syndrome.

Several level U recommendations were also made, given a lack of evidence in these areas:

• There is insufficient evidence to support or refute the efficacy of other transverse myelitis therapies or the usefulness of ethnicity to determine the cause of a subacute myelopathy.
• There is insufficient evidence to support the efficacy of other therapies, the authors write, although they note that despite the absence of evidence, high-dose intravenous methylprednisolone, given in a dose of one gram daily for three to seven days, "is typically the first treatment offered to hasten recovery, reduce disease activity, and restore neurology function."
• There is insufficient evidence regarding the use of other immunosuppressive strategies to reduce the risk for future attacks of transverse myelitis.

Although transverse myelitis is uncommon, making reliable data difficult and expensive to collect, the authors write in a clinician summary that accompanies the report that "the devastating effects...make urgent treatment critical to minimize disability."

In the likely absence of existing policy for treatment of this condition from either government programs or private insurers, "medical review staff should allow for requests for individual consideration with each case [claim] with reference to published articles or other resources — even if those resources are judged as 'lower class' evidence — and further dialogue in case additional data are needed."

They note that a good source of treatment protocols are those used in MS centers.

A variety of physician tools, including the clinician and patient summaries, a slide set, a clinical case example, and a podcast are available for download on the AAN's Web site.

The guideline was funded by the American Academy of Neurology. The article notes that no authors received honoraria or financial support to develop this document. Disclosures for coauthors appear in the article.

Neurology. 2011;77:2128-2134. Full text

Susan Jeffrey • Medscape Medical News © 2011 WebMD, LLC