van der Vuurst de Vries RM, et al. - Researchers examined the diagnostic accuracy of the 2017 criteria vs the 2010 criteria in the prediction of clinically definite MS in patients with a typical clinically isolated syndrome (CIS). Compared to the previous 2010 criteria, the 2017 revised McDonald criteria were identified to have greater sensitivity but less specificity for a second attack. The tradeoff is that, in patients with a less active disease course, it leads to a higher number of MS diagnoses.

Methods

• The inclusion criteria was fulfilled by a total of 251 patients at Erasmus MC, Rotterdam, the Netherlands, in collaboration with several regional hospitals.
• Early in the diagnostic process, 13 patients received another diagnosis and therefore were excluded from the analyses.
• Participation was declined by 9 patients with CIS.
• This prospective CIS cohort thus included 229 patients between March 2006 and August 2016.
• Within 3 months after onset of symptoms, patients underwent a baseline magnetic resonance imaging scan and, if clinically required, researchers performed a lumbar puncture.
• Between December 2017 and January 2018, data analysis was done.
• For the 2017 vs the 2010 criteria, they determined sensitivity, specificity, accuracy, and positive and negative predictive value after 1, 3, and 5 years.

Results

• One hundred sixty seven were women (73%) among the 229 patients with CIS; the mean (SD) age was 33.5 (8.2) years.
• Clinically definite MS (CDMS) was diagnosed in 113 patients (49%) during a mean (SD) follow-up time of 65.3 (30.9) months.
• For the 2017 criteria compared to the 2010 criteria, higher sensitivity (68%; 95% CI, 57%-77% vs 36%; 95% CI, 27%-47%; P < .001), but lower specificity (61%; 95% CI, 50%-71% vs 85%; 95% CI, 76%-92%; P < .001) were evident.
• More MS diagnoses could be made at baseline using the 2017 criteria (n = 97 [54%]; 95% CI, 47%-61% vs n = 46 [26%]; 95% CI, 20%-32%; P < .001).
• In the group with at least 5 years of follow-up, a second attack during follow-up was not encountered in 33% of patients who were diagnosed as having MS using the 2017 criteria vs 23% when using the 2010 criteria.