Background Recently, the International Paediatric Multiple Sclerosis Study Group (IPMSSG) definitions for the diagnosis of immune-mediated acquired demyelinating syndromes (ADS) of the central nervous system, including paediatric multiple sclerosis (MS), have been revised.

Objective To evaluate the 2012 revised IPMSSG consensus definitions in a cohort of children with ADS prospectively followed from January 2007.

Methods Children with ADS who had an MRI scan obtained within 90 days after first disease onset were included. The sensitivity and specificity of the 2007 and 2012 IPMSSG consensus definitions were assessed. The time to MS diagnosis applying the 2007 and 2012 definitions was compared using survival analysis and log-rank test.

Results 82 children with ADS were included. 35 children were diagnosed with paediatric MS, of whom 30 experienced a second clinical event. The final diagnosis corresponded applying either the 2007 or 2012 IPMSSG definitions. The revised 2012 definitions had sufficient sensitivity (80%) and high specificity (100%). MS diagnosis was made 3.4 months earlier (χ²=8.24, p=0.004) applying the new definitions. In 14 children, MS diagnosis was made at first MRI.

Conclusions MS diagnosis can be made reliable and early using the 2012 IPMSSG consensus definitions. This is beneficial for adequate counselling of children and their families and for early treatment possibilities.