Younger children with MS have a distinct CSF inflammatory profile at disease onset.
BACKGROUND
The clinical and MRI presentation differs between earlier- and later-onset pediatric multiple sclerosis (MS), whereas the effect of age on the CSF inflammatory profile is unknown and may contribute to delayed diagnosis.


OBJECTIVE
To compare the CSF cellular and immunoglobulin G (IgG) profiles between earlier- and later-onset pediatric MS.


METHODS
We queried the databases of 6 pediatric MS centers for earlier-onset (onset <11 years) and later-onset (> or = 11 and <18 years) patients with MS or clinically isolated syndrome who underwent CSF analysis within the first 3 months of presentation (observational study). We compared CSF white blood cell (WBC) differential count, IgG index, and IgG oligoclonal bands between age groups.


RESULTS
We identified 40 earlier-onset (mean age at onset = 7.2 +/- 2.7 years, 60% females) and 67 later-onset pediatric MS patients (15.1 +/- 1.7 years, 63% females). Although WBC count tended to be higher in earlier-onset patients (median = 9/mm(3) [0-343] vs 6 [0-140], p = 0.15), they had a lower proportion of lymphocytes (70% [0-100] vs 93% [0-100] of WBCs, p = 0.0085; difference = +3% per 1-year increase of age, p = 0.0011) and higher proportion of neutrophils than later-onset patients (0.5% [0-75] vs 0% [0-50] of WBCs, p = 0.16; difference = -1% per 1-year increase of age, p = 0.033). In earlier-onset disease, fewer patients had an elevated IgG index than in the later-onset group (35% vs 68% of patients, p = 0.031).


CONCLUSIONS
Age modifies the CSF profile at pediatric multiple sclerosis (MS) onset, which may mislead the diagnosis. Our findings suggest an activation of the innate rather than the adaptive immune system in the earlier stages of MS or an immature immune response.
Chabas
D
D
UCSF Regional Pediatric MS Center, 350 Parnassus Ave., Suite 908, San Francisco, CA 94117, USA. dchabas@gmail.com
Ness
J
J
Belman
A
A
Yeh
E A
EA
Kuntz
N
N
Gorman
M P
MP
Strober
J B
JB
De Kouchkovsky
I
I
McCulloch
C
C
Chitnis
T
T
Rodriguez
M
M
Weinstock-Guttman
B
B
Krupp
L B
LB
Waubant
E
E
D000293:Adolescent; D000367:Age Factors; D017668:Age of Onset; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000134:cerebrospinal fluid*; D007958:Leukocyte Count / Q000379:methods; D008137:Longitudinal Studies; D008297:Male; D009103:Multiple Sclerosis / Q000134:cerebrospinal fluid* / Q000276:immunology*; D010372:Pediatrics; D016016:Proportional Hazards Models; D012720:Severity of Illness Index
D007074:Immunoglobulin G