Multiple Sclerosis: Causes, Symptoms, Diagnosis, and Treatment

Multiple sclerosis (MS) is, in basic terms, an inflammatory condition whereby an individual's immune system attacks, and causes damage to the protective sheath covering the nerves (also referred to as myelin) thereby disrupting normal communication between the spinal cord, the brain, and the rest of the body. Myelin provides some form of cover to the nerves, and when it is damaged, nervous axons, which are responsible for the conduction of impulses, do not function effectively. Moreover, with continued loss of myelin, the nerves become more prone to damage, and gradually deteriorate, causing the patient to develop symptoms as a result of lost or diminished impulses. The symptoms experienced will depend on the nerves affected, as well as the extent of damage. It is estimated that around 400,000 persons in the U.S. suffer from MS.

Causes

The actual cause of MS is yet to be discovered; however, most theories describe it as an auto-immune disease caused by various factors ranging from childhood viral infections to genetics (Mayo Clinic, 2014; National MS Society, 2014). Vitamin D deficiency and over-consumption of salt have also been identified as other possible causes of the disease, but these are theories that are yet to be proven.

Risk Factors

So, what would actually make one individual more prone to MS, compared to another?

Age: MS has been found to be more common among people of younger ages, particularly those aged between 15 and 60 (Mayo Clinic, 2014). The disease is very rare among young children, and the elderly.

Gender: Women, compared to men, have significantly higher chances of developing MS, particularly because the HLA-DRB1*15 gene, which has been associated with MS susceptibility, is more likely to be found and thrive in women as compared to men (National MS Society, 2014b).

Autoimmune Diseases: persons with inflammatory bowel disease, thyroid disease, and type 1 diabetes are more at risk of developing MS.

Geographical Factors: MS has been found to be more common among people living far away from the equator. It is more prevalent in Europe, northern U.S., Southern Australia, New Zealand, and Southern Canada; and less common in Africa and Asia (Mayo clinic, 2014). According to the National Multiple Sclerosis Society (National MS Society, 2014a), the high prevalence rates in temperate zones is due to the fact that such zones experience relatively low amounts of sunlight, and people in such areas have lower levels of vitamin D, which is believed to protect the body against immune-mediated health conditions.

Family History: genetics do have a critical role to play in the development of MS - one has a higher risk of developing the disease if they have a first-degree relative with the same (Mayo Clinic, 2014). However, the risk has been found to be relatively low.

Infectious Factors: childhood exposure to such viruses as Epstein Barr, which causes mononucleosis and other bacteria and microbes recognized as causes of myelin damage increases one's risk of contracting MS (Mayo Clinic, 2014; National MS Society, 2014a).

Signs and Symptoms

An MS patient will experience symptoms based on the affected nerve. Visual changes, and in extreme cases, vision loss, is, for instance, likely to be experienced if the optical nerve is affected. General symptoms, nonetheless, include;

i) Weakness, tingling, or numbness on one side of the body. The weakness could range from mild to severe, in which case paralysis could result

ii) Visual changes or vision loss, and in some cases, pain when moving the eye

iii) Incontinence, and difficulty emptying bladder

iv) Dizziness

v) Fatigue

vi) Slurred speech

vii) Electric-shock sensations mostly experienced during neck movements

Types of MS/Disease Course

MS could be categorized into four distinct types -- relapsing-remitting MS, secondary-progressive MS, primary-progressive MS, and progressive-relapsing MS (Mayo Clinic, 2014). The four differ in terms of consistency of symptoms. Most MS patients report relapsing-remitting courses, where symptoms are experienced over several days or weeks (relapse), and then disappear, only to reemerge (remission) after a long period of time, at times up to 1 year (Mayo Clinic, 2014). However, most patients with this kind of relapsing-remitting MS end up developing primary-progressive MS, where symptoms progress for prolonged periods without remission (Mayo Clinic, 2014). Secondary-progressive MS comes about when symptoms are not diagnosed and addressed effectively during a remission, causing the patient to suffer a relapse after a relatively short period of time. The final type of MS, progressive-relapsing MS is diagnosed when a patient reports escalating symptoms that are often accompanied by intermittent remission episodes.

Diagnosis

There are three physical tests that can be used to diagnose MS. The most common of these is the MRI (magnetic resonance imaging) scan, where the physician images the spinal cord and the brain to identify signs of injury. Additionally, a lumbar puncture, which entails testing cerebrospinal fluid for the presence of inflammatory markers or proteins, could be used to detect injuries to the central nervous system. The third possible test is the evoked potentials test which identifies subclinical injury areas by showing slowed response times in the brainstem, the spinal cord, the auditory nerve, and the optic nerve.