Real-world validation of the 2017 McDonald criteria for pediatric MS

OBJECTIVE: To compare the diagnostic accuracy of the McDonald 2017 vs the McDonald 2010 criteria to predict a second attack of MS (clinically definite MS [CDMS]) at the first attack of acquired demyelinating syndromes (ADS). METHODS: One hundred sixty-four children (aged <18 years) with an incident attack of ADS were included in a prospective multicenter study between June 2006 and December 2016. Brain (and spinal if available) MRI was performed ≤3 months after symptom onset. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were compared at baseline between the 2010 and 2017 criteria. RESULTS: Among the 164 patients, 110 patients (67%) presented without encephalopathy (ADS–, female 63%; median age 14.8 years, IQR 11.3–16.1years) and 54 (33%) with encephalopathy (acute disseminated encephalomyelitis [ADEM], female 52%; median age 4.0 years, IQR 2.6–6.1 years). Of the 110 ADS– patients, 52 (47%) were diagnosed with CDMS within a median follow-up of 4.5 years (IQR 2.6–6.7 years). The sensitivity was higher for the 2017 criteria than for the 2010 criteria (83%; 95% CI 67–92, vs 49%; 95% CI 33–65; p < 0.001), but the specificity was lower (73%; 95% CI 59–84 vs 87%; 95% CI 74–94, p = 0.02). At baseline, 48 patients fulfilled the 2017 criteria compared with 27 patients when using the 2010 criteria. The results for children aged <12 years without encephalopathy were similar. In patients with ADEM, 8% fulfilled the 2010 criteria and 10% the 2017 criteria at baseline but no patient fulfilled the criteria for CDMS. CONCLUSIONS: The McDonald 2017 criteria are more sensitive than the McDonald 2010 criteria for predicting CDMS at baseline. These criteria can also be applied in children aged <12 years without encephalopathy but not in children with ADEM. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that in children with ADS, the 2017 McDonald criteria are more sensitive but less specific than the 2010 McDonald criteria for predicting CDMS.