====== Multiple Sclerosis ======


====== Causes ====== There currently is no known cause for the affliction of MS; however the general consensus is that which follows both environmental as well as genetic factors contributing to the emergence of the disease (Dyment et al. 2004). There is a variance in the amount of environmental factors thought to influence the presence of MS. Many theories attempt to analyze different combinations of risk factors with hopes of coming to a conclusion which explains the emergence of MS; however none have been successful (Dyment et al. 2004). Some of the most prominent environmental risk factors include an array of microbes (Ascherio & Munger, 2007). Microbes vary depending on geographic region and it is thought that a change in exposure to a set of microbes native to a specific location is what increases the risk of developing MS (Ascherio & Munger, 2007). A theory which further investigates this ideology is that of the hygiene hypothesis. It states that in early life contact with infections are beneficial to the individual, with later exposure to high risk microbes resulting in the development of MS further along in life (Compston & Coles, 2008). Therefore an individual who has recently moved to an area with high risk microbes is more likely to acquire MS due to its novelty to their immune system. In addition to microbes there is evidence in support of a virus as a candidate for causing MS (Ascherio & Munger, 2007). An example of this would be the human herpes virus (hhv), more specifically hhv-4, which is one of the 8 different known strains of hhv (Gildan, 2005). The majority of the human population has been exposed to at least one strain of the hhv, with one of the most common being the Varicella zoster virus which causes chickenpox or shingles (Gildan, 2005). Studies show that individuals who have not previously been infected with hhv-4, otherwise known as the Epstein-Barr virus are at less of a risk of acquiring MS compared to those who have previously contracted it (Gildan, 2005). Furthermore according to the hygiene hypothesis individuals exposed to the Epstein-Barr virus as youths have a reduced risk of being affected by MS as opposed to the higher risk experienced by adults since it is their first interaction with the causative virus in a relatively later stage in life which acts as a trigger (Gildan, 2005). While believed by many, MS is not categorized as a hereditary disease (Dyment et al. 2004). Instead its connection with genetics lies within the chance of genetic variation leading to increase risk in developing the disease (Ascherio & Munger, 2007). Due to the similarity of genetic expression found among related individuals, the probability of developing MS is increased when comparing with an afflicted member of the family versus the general public (Ascherio & Munger, 2007). In addition, MS is more prevalent in certain ethnic groups than others due to the genetic expression variance (Ascherio & Munger, 2007). More specifically there are a few genes which when mutated are more likely to be linked with MS, they are found in the human leukocyte antigen (HLA) system (Ascherio & Munger, 2007). Mutations in this system have been shown to be susceptible to the progression of various autoimmune diseases including type-1 diabetes (Ascherio & Munger, 2007). In general research show that changes in the HLA system are responsible for between 20 to 60 percent of the genetic predisposition to MS (Ascherio & Munger, 2007).
====== Symptoms ====== MS symptoms vary from person to person (Multiple Sclerosis Clinical Presentation, 2016). MS Symptoms include: * Sensory loss * Walking difficulty * Spasticity * Bladder, bowel, and sexual dysfunction * Tremors * Optic neuritis * Heat intolerance * Fatigue * Pain * Cognitive difficulties * Constipation
====== Diagnosis ======
====== Pathophysiology ====== **Effect of Demyelination:** After demyelination, the nerve tissue is damaged and the axons are not able to conduct action potentials effectively due to loss of myelin, which ultimately acts as an insulator. This prevents the body to communicate with the Central Nervous System effectively, therefore causing numbness in certain areas of the body (Smith and McDonald, 1999).













====== Treatment and Management ======
====== Conclusion ====== Multiple Sclerosis is an inflammatory, autoimmune disease which disrupts the neurons’ ability to trigger action potentials. As of today, the pathophysiology of this disease is not fully understood, however, considerable advances have been made in understanding the factors behind this disease. It is evident that further research needs to be conducted to figure out the precise mechanism of the demyelination and remyelination process. The findings of this research will lead to more efficient treatment mechanisms and may even lead to a cure for Multiple Sclerosis.
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