Multiple sclerosis: Unveiling current immunogenetic factors and their role in etiopathogenesis and clinical aspects

Multiple sclerosis (MS) is the most common cause of neurological deficits among the young population. While the prevalence of MS is increasing worldwide, the incidence rate of MS is also undergoing a similar trend in Lithuania. Globally, women are twice as likely to be affected by MS as men. Unilateral optic neuritis is the most common initial symptom of MS. The signs and symptoms of MS vary greatly from patient to patient and depend on the location and severity of the nerve fiber damage in the central nervous system. Most people with MS have a relapsing-remitting disease course or clinically isolated syndrome. They experience periods of new symptoms or relapses that develop over days or weeks and usually resolve partially or completely. These relapses are followed by quiet periods of disease remission that may last months or even years. Data accumulated over the years suggest a complex interplay between environment and immunogenetics (strong associations with a large number of immune and genetic markers), and an increasingly convincing role of an underlying degenerative process leading to demyelination (in both white and gray matter), axonal and neurosynaptic damage, and a persistent innate inflammatory response, with T-cell-mediated autoimmunity appearing to play a diminishing role as the MS develops and progresses. In the absence of clinically proven, accurate, and reliable biomarkers, the disease can take a progressive course in case of late treatment, signifying the critical need for early diagnosis. This article therefore discusses the etiopathogenesis and clinical aspects of MS.