[1] Univ Copenhagen, Dept Pediat, Rigshosp, Copenhagen, Denmark
[2] Univ Copenhagen, Danish Multiple Sclerosis Ctr, Dept Neurol, Rigshosp, Copenhagen, Denmark
[3] Statens Serum Inst, Dept Autoimmun & Biomarkers, Copenhagen, Denmark
[4] Hosp Reg Zealand, Dept Clin Biochem, Copenhagen, Denmark
[5] Odense Univ Hosp, Dept Clin Biochem & Pharmacol, Odense, Denmark
[6] Univ Copenhagen, Dept Clin Biochem, Rigshosp, Copenhagen, Denmark