The presence and frequency of cortical lesions (CLs) in 24 pediatric patients with relapsing-remitting multiple sclerosis (RRMS) were compared to 15 adult patients with RRMS and 10 pediatric healthy controls, in a study at University Ospedale San Raffaele, Milan and other centers in Italy. Pediatric patients had shorter disease duration and lower disability than adults. On MRI DIR sequences 3-dimensional T1-weighted scans, white matter lesion number and volume did not differ between pediatric and adult patients. CLs occurred in 2 (8%) pediatric patients and 10 (66%) adult patients. After adjusting for age, gender, and disease duration, median CL volume and number of CLs were lower in pediatric than adult patients with RRMS (p=0.0003). All CLs in pediatric patients were located at the boundary between white and gray matter. CL formation is not likely to be an initial event in pediatric MS. [1]

COMMENT. Cortical lesions are rare in pediatric patients with MS. Compared to adults, children with MS have a relative sparing of brain gray matter. Clinically, an earlier age of onset is associated with specific features including more frequent encephalopathy, seizures, and brainstem and cerebellar symptoms during the first event [2]. These researchers at the UCSF MS Center report the initial brain MRI scan of younger patients shows more frequent involvement of the posterior fossa and higher numbers of ovoid, ill-defined T2-bright foci that often partially resolve on the follow-up scan. The spinal fluid in younger patients may fail to reveal oligoclonal bands or elevated IgG index at disease onset. No therapy for MS in children has been approved by the US Food and Drug Administration. As a result, physicians have started to use off-label drugs approved for adults.