CSF cellular and immunoglobulin G (IgG) profiles in 40 earlier-onset (<11 years) and 67 later-onset (>11 and <18 years) pediatric MS patients were compared in a multicenter US study. Earlier-onset patients had a mean age of 7.2 +/- 2.7 years (60% female), and later-age patients 15.1 +/- 1.7 years (63% female). CSF white blood cell counts were higher in earlier-onset patients (median^ 9 mm3 vs 6mm3 (p=0.15) but had a lower proportion of lymphocytes (70% vs 93%, p=0.0085) and a higher proportion of neutrophils (p=0.033). An elevated IgG index occurred in fewer earlier-onset disease patients than in the later-onset group (35% vs 68%, p=0.031). An activation of the innate rather than the adaptive immune system in the earlier stages of MS is suggested or an immature immune response. [1]

COMMENT. The CSF profile in pediatric MS is dependent on age of onset, and the age-related variations are important in diagnosis. Pohl D et al [2] reported the CSF characteristics of 136 childhood-onset (<16 years) cases of MS. CSF pleocytosis occurred in 66%, and oligoclonal IgG in 92%.