Assessment of the new diagnostic criteria for idiopathic ATM

Investigators evaluating the usefulness of new diagnostic criteria for idiopathic acute transverse myelitis (ATM) say that they represent a major advance in the management of the disease, but that one in ten patients meeting the criteria still progress to MS.The new criteria from the Transverse Myelitis Consortium Working Group have been established to help select homogenous groups of patients for clinical trials, but the authors of the trial evaluating their usefulness note, "However, in our experience, even when applying the restrictive criteria of the Working Group, a considerable proportion of patients with definite or possible ATM may progress to MS. This would be an important consideration when selecting patients for trials involving disease-modifying therapies aimed at delaying the onset of MS."The study involved 24 patients who fulfilled the clinical, radiological and serological criteria for definite ATM and 21 for possible ATM. Five of the patients converted to MS at a mean of 18 ± 14.4 months follow-up; three of the patients presented with criteria for possible ATM and two for definite ATM. All five patients were female, and were younger than those in the ATM group.The authors say, "Our study highlights that two more factors, sex (female population) and age at onset of symptoms (younger patients) may represent additional aids for detecting patients at greater risk of developing clinically defined MS." They add that the number of spinal MRI levels affected (less than two) may also help, as their study found that the MS group presented with fewer affected levels than the ATM group.With respect to functional recovery, the authors found that a higher admission Rankin score and an increased CSF glucose were significantly related to worse outcome Rankin score. Therefore, they suggest that modified Rankin score and possibly CSF glucose levels may be useful in stratifying patients involved in ATM clinical trials. Reference...