Understanding Multiple Sclerosis

M

ultiple sclerosis (MS) is a complex, demyelinating neurological disorder that occurs primarily due to an alteration in the immunological mechanisms that normally protect the body from foreign organisms. As a result of these alterations, our body identifies normal cells in the body as foreign and begins attacking these cells. The myelin sheath, or protective covering, that surrounds the nerve fibers and assists in the transmission of signals becomes the target of this misguided immunological attack leading to delays in the transmission of signals from the brain and spinal cord.

Multiple sclerosis affects females up to three times more commonly than males, and it is commonly seen in patients between the ages of 20 and 40 years old. Different ethnic groups are affected by the disease, but it is more common in Caucasians than in African Americans or Hispanics. The precise mechanism involved in causing MS is unknown, but several risk factors have been identified. Although MS is not an inherited disease, there is an increased risk of multiple sclerosis in patients with positive family history. People who are born and raised in areas that are further away from the equator (such as colder northern regions) have a higher risk of developing multiple sclerosis as well. Low vitamin D levels, smoking and obesity have also been recognized as risk factors for MS.

 

Multiple sclerosis patients present with a multitude of symptoms ranging from typical clinical presentations to atypical symptoms. Typical clinical presentations include optic neuritis, loss of vision in one or both eyes often associated with painful eye movements; weakness or numbness in one or more limbs that develops rapidly over a few hours or days and improves in a few days or weeks; double vision which starts suddenly and gradually improves in a few weeks; balance issues and falls. Atypical symptoms include heat sensitivity, shock- like sensations along the spine that may be triggered by head movements, bladder symptoms such as urgency, frequency and incontinence, sexual dysfunction, muscle stiffness and depression. No matter the symptom type, fatigue is the most common symptom in patients with MS, as about 80- 90 percent of the patients experience it.

 

Based on the pattern of presentation of these symptoms, multiple sclerosis is classified as relapsing-remitting, primary progressive or secondary progressive type. Medications used to manage multiple sclerosis are called disease-modifying therapies. With time most relapsing-remitting patients convert into progressive disease type. The disease- modifying therapies aim to delay this progression by suppressing the immune system. Commonly used medications are oral medications, intravenous infusions and injectable medications. Treatment is usually tailored based on patient preference, disease severity and lab tests performed to screen for infections. In new developments for the disease, stem cell therapy and BTK inhibitors are experimental therapies currently showing promising results and may be available in the near future.

Arvin Parvathaneni, MD, MPH
Clinical Assistant Professor of Neurology
LSU Health Shreveport.