Multiple Sclerosis in Children Is More Common Than Thought

Multiple sclerosis is increasingly being diagnosed in children and teens. Although physicians have long known that kids can come down with the disease, new technology and emerging awareness of the problem have led them to spot the kind of cases that previously had gone undetected until years later. Among the 400,000 cases of MS diagnosed in the United States, 10,000 are pediatric cases, although neurologists think that there are probably many other cases being missed. "There may be up to 20,000 children with MS," says UCSF researcher Emmanuelle Waubant, MD, PhD. Even after diagnosis, children with MS and their parents are confronted by issues not faced by adult patients, Waubant says. After an MS diagnosis, children may be seen by adult neurologists who specialize in MS, but have little experience with children, or by pediatric neurologists who have little experience with the disorder, she says. The epidemiology and course of the disease are also different in children than in adults, and there may be a lack of information about the pediatric safety and efficacy of drugs used to treat adult MS. Such concerns have led to the creation of the newly opened UCSF Regional Pediatric MS Center (see accompanying story). How Multiple Sclerosis Manifests in Children
Multiple sclerosis in children manifests itself differently than MS in adults, researchers say. In children, MS may begin after a first bout of neurological symptoms (called acute disseminated encephalomyelitis, or ADEM), which is felt to be temporary. "Most children with ADEM make a nice recovery and never have other symptoms, but a certain proportion continue to have symptoms and new symptoms occur later, thereby meeting the criteria of MS," Waubant says. The disease is thought to progress more slowly in children, but that is debatable when looking at an ethnically mixed population, Waubant says. The epidemiology of the disease also presents a different picture in adults and children. In adults, women get MS more often than men, but until puberty, MS afflicts boys and girls equally. And while the adult disease predominates among whites, in pediatric patients the pattern is the reverse, says Waubant, with far higher incidence and possible severity among minority children. The cognitive consequences of MS are likely to be greater in children than in adults, possibly because children are still developing those skills and do not have sufficient cognitive capacity to fall back upon. "If children with MS are away from school for long periods, that only adds to the impact MS might have on their cognitive development," Waubant says. Pediatric MS Might Teach Us Much About MS in General
The study of pediatric MS offers the possibility of learning much more about the mysterious etiology of MS in general, researchers say. Multiple sclerosis has long been thought to have both genetic and environmental causes, but no specific environmental factor has been identified. In part, this is because the disease may strike long after exposure to such a factor. "Studying MS in children is offering a new window into studying environmental factors because the onset has to be much closer to the environmental exposure," Waubant says. Physicians treating children with MS face other complications. Because drugs for MS are tested in adults, physicians have often been hesitant to administer them without knowing that they are safe and efficacious in children. "This was also important because families' health insurance plans would deny coverage for these drugs," Waubant says. Waubant led the first study of the safety of using interferon to treat MS in children. Since then, others have collected retrospective or prospective data to show that adult MS drugs are safe in children. Because of the nature of these studies, it will remain unclear how efficacious the drugs are in children. Links: UCSF Opens Pediatric MS Center