Multiple sclerosis, medically known as encephalomyelitis disseminata is a chronic autoimmune disease that disturbs the activities of the central nervous system i.e., the brain and the spinal cord by deranging the flow of information between the body and the brain. In autoimmune disorders, immune system attacks healthy body tissues, considering them as foreign agents like virus or bacteria.
In multiple sclerosis, inflammation occurs in the myelinated nerve fibers as immune system attacks them. It results in scars or sclerosis in various regions of the nerve fiber because myelin sheath is damaged. That’s why it is called multiple sclerosis which means “scars in various areas of the nerve fiber.”
As myelin increases the efficiency and speed of the nerve fibers, damaged myelinated nerve fibers do not conduct electrical signals effectively. Multiple sclerosis mainly disturbs the functions of these parts:
- the spinal cord
- the stem of the brain
- the cerebellum, region of brain that controls body movement and balance
- the optic nerves of brain that transmit electrical impulses from retina to the brain
As the damage increases, the nerve fibers will break apart and no longer capable of carrying electrical signals from brain to the target nerve. Eventually, the body will fail to carry out its normal functioning.
Types of multiple sclerosis[i]
There are four types of multiple sclerosis based on the progression of disease with the passage of time.4
- Clinically isolated syndrome
Clinically isolated syndrome is preliminary condition of the multiple sclerosis having a single episode having symptoms that last for atleast one day. It happens due to demyelination of the nerve fibers. CIS will change into relapse-remitting multiple sclerosis if the episode occurs again.
- Relapse-remitting Multiple Sclerosis
About 85% of the patients are diagnosed with RRMS in which relapses, the exacerbation of the episodes of symptoms, occur. The symptoms may disappear on their own or by treatment or attacks may persist over several years. The gap between attacks is called period of remission. So, RRMS is accompanied with periods of relapse and remission. The symptoms aggravate over the course of time with each attack.
- Primary progressive Multiple Sclerosis
In PPMS symptoms gradually exacerbate without relapses or remission over years. There occurs period of stability and periods during which symptoms increase. Almost 15% patients are diagnosed with PPMS.
- Secondary progressive Multiple Sclerosis
Secondary progressive MS (SPMS) occurs when RRMS transitions into the progressive form. people will experience episodes of relapse and remission, but then the disease will start to progress steadily
Progressive relapsing multiple sclerosis is a rare condition prevalent in only 5% of the multiple sclerosis patients. Relapses are seldom, but symptoms exacerbate in between different relapses. Its symptoms resemble with that of PPMS (primary progressive multiple sclerosis).
Signs and symptoms of multiple sclerosis
The symptoms associated with multiple sclerosis are not common to every individual infact, they vary from one individual to another widely. The symptoms linked with multiple sclerosis include:
- Tiredness
- Difficulty in walking
- Numbness of different parts of the body particularly face, legs and arms
- Muscles weaken due to damaging of nerve fiber
- Problems with the vision like blurred vision, partial or complete loss of sensation, pain while moving the eye due to inflammation of the optical nerve etc. It is one of the earliest indicators of multiple sclerosis and do not affect both eyes simultaneously.
- Issues with balance, coordination which results in dizziness and spinning of head.
- It becomes difficult for the patient to organize his activities, affects multitasking, planning and learning
- Demyelination of the nerve fibers initiate emotional traumas
- Frequent and uncontrolled urge to urinate due to loss of bladder function alongwith urinary tract infections in some cases
- Constipation leading to fecal incontinence
- Loss of sexual desire
- Other least common symptoms are headache, loss of hearing and speech, respiratory disorders, tingling sensation, convulsions, problem with swallowing food, restricted or no mobility, loss of heat sensation, etc.
Symptoms occur in phases or may worsen over the course of time depending on the category of multiple sclerosis diagnosed. The progress of multiple sclerosis also varies among different individuals. Sometimes, its symptoms do not progress for months or years, while for some individuals it occurs rapidly.
Causes and risk factors
The cause of multiple sclerosis is less known to the doctors but researchers believe that it is triggered by various environmental factors like a toxin or virus that make the immune system to attack body’s own cells and produce an auto immunological response.
Multiple factors like genetic factors triggered by the environment can also cause multiple sclerosis i.e., a person having a parent or sibling with multiple sclerosis is more likely to develop MS. A person who smokes is more prone to MS and have more lesions as compared to the non-smoker. Women are more likely to develop symptoms of MS than men. Low levels of vitamin D affects the activity of the immune response. Vitamin B12 produces myelin, its deficiency increase the susceptibility of multiple sclerosis.
There is not a single test to diagnose multiple sclerosis, several strategies are employed to comply with the requirements for a diagnosis. A physiologist will conduct a physical as well as neurological testing while considering the symptoms and the medical history of the patient. Some of the diagnostic techniques include:
- Magnetic resonance imaging (MRI) of the brain and spinal cord to reveal lesions or scars.
- Fluid analysis of the spinal cord will help to identify antibodies indicative of previous infection
- evoked potential test, to assess the electrical activity of the nerve impulse
Treatment of multiple sclerosis[ii]
Multiple sclerosis cannot be cured but there are treatments that slow down the advancement of the disease, lessen the chances of relapse and cure the symptoms. Some of the treatments are:
- Medications to prevent the progression of the disease
The treatment of multiple sclerosis constitutes the use of the disease-modifying therapies (DMTs) beta-interferons and glatiramer acetate. They function by changing activities of the immune system. The disease modifying therapies approved by food and drug administration (FDA) currently include:
- Medications delivered via injections are Avonexand Rebif, Betaseron and Extavia, Copaxone and Glatopa, Plegridy, etc.
- Orally delivered medications are Aubagio, Gilenya, Tecfidera, cladribine, Siponimod, etc.
- Infused medications are Lemtrada, Novantrone, Ocrevus, Tysabri,etc.
- Complementary therapies to assist the recovery process may include:
- exercise
- healthy diet like fruits, vegetables, lean proteins, nuts, low fat dairy products, etc.
- massage for pain
- acupuncture
- stressreduction
- non-smoking
- Plasma exchange
Exchange of plasma involves replacing the blood plasma with new plasma to removes antibodies from the blood that are producing autoimmune response. It is only preferable for severe multiple sclerosis.
[i] https://www.nhs.uk/conditions/multiple-sclerosis/
[ii] https://www.medicalnewstoday.com/articles/37556#treatment
