There are several identified genetic and environmental risk factors for pediatric multiple sclerosis. Some of the identified environmental risk factors include exposure to certain viruses, vitamin D deficiency, and second-hand tobacco smoke exposure. The main genetic risk factors involved in development of pediatric onset multiple sclerosis (POMC) is variation in Human Leukocyte Antigen (HLA)-DRB1 *1501 and familial history [1].
Genetic Risk Factors
Familial susceptibility of multiple sclerosis has been studied on many occasions and demonstrated a 25% risk of developing multiple sclerosis in monozygote twins compared to a 2-5% risk rate in dizygote twins and first-degree relatives [2]. Many Human Leukocyte Antigens (HLA) including …show more content…
Vitamin D is naturally produced by our body from sun exposure and plays a critical role in nutrition absorption and regulation of normal immune response. Vitamin D plays an immunoregulatory role through upregulation of T-cell activity and anti-inflammatory molecules and downregulation of pro-inflammatory cytokines during acute phases. Vitamin D also contributes to myelin repair mechanisms [1]. This evidence is supported by a higher prevalence of multiple sclerosis observed in people living in northern latitudes compared to those living closer to the equator. Also, a prospective cohort study within the pediatric population done by a Canadian national showed relationship between low serum 25(OH)D level during the first presentation of symptoms with increased risk of subsequent multiple sclerosis diagnosis. Not only does low vitamin D level have positive correlation with developing multiple sclerosis, but also, low levels are inversely related to relapse risk [3].
Exposure to second-hand smoking is another risk factor of pediatric onset multiple sclerosis. The relative risk for first incidence of multiple sclerosis in those exposed to smoke was 1.37 times greater in children 10 years of age [1, 4]. “Smoking and Multiple Sclerosis: An Updated Meta- Analysis” states that smoking at an early age leads to increased probability of progressive, severe multiple sclerosis