Multiple Sclerosis In-Depth Report

Stuart SchlossmanMultiple Sclerosis

Multiple Sclerosis In-Depth Report

Background

Multiple sclerosis (MS) is a neurological disease that involves the central nervous system (CNS), the nerves that comprise the brain and spinal cord. It has two major features:
  • Destruction of myelin, a fatty insulation covering the nerve fibers, is the main characteristic of MS. The end results of this process, called demyelination,are multiple patches of hard, scarred tissue called plaques or lesions. Sclerosis comes from the Greek word skleros, which means hard.
  • Damage of axons, the fibers that carry electric impulses away from a nerve cell, is also a major factor in the permanent disability that occurs with MS.

Myelin is the layer that forms around nerves. Its purpose is to speed the transmission of impulses along nerve cells.
The symptoms, severity, and course of MS vary widely depending partly on the sites of the plaques and the extent of the demyelination.

AUTOIMMUNE DISEASE PROCESS

Multiple sclerosis is thought to be an autoimmune disorder. In autoimmune diseases, immune factors attack the body’s own cells. In the case of MS, the immune system attacks the tissues that make up myelin. The damage to myelin, and nerve fibers (axon), is caused by overactivated T cells. T cells are a type of white blood cells called lymphocytes.

TYPES OF MULTIPLE SCLEROSIS

Doctors generally group multiple sclerosis into four major disease course categories:
  • Relapsing-Remitting MS. Relapse-remitting MS (RMSS) is the most common form of multiple sclerosis. About 85% of patients are first diagnosed with this type of MS RMSS is marked by flare-ups (also called relapses or exacerbations) of symptoms followed by periods of remission when symptoms improve or disappear.
  • Secondary-Progressive MS. Some patients with RMSS go on to develop secondary-progressive (SPMS). (For many patients, treatment with disease-modifying medications helps delay this progression.) In SPMS, the disease course continues to worsen with or without periods of remission or leveling off of symptom severity (plateaus).
  • Primary-Progressive MS. About 10% of patients are diagnosed with primary-progressive MS (PPMS). In PPMS, symptoms continue to worsen gradually from the very beginning. PPMS has no relapses or remissions. There may be periods of occasional plateaus. This type of multiple sclerosis is more resistant to the medications typically used to treat the illness.
  • Progressive-Relapsing MS. Progressive-relapsing MS (PRMS) is a rare form of MS, occurring in less than 5% of patients. It is progressive from the start with intermittent flare-ups of worsening symptoms along the way. There are no periods of remission.

Symptoms

Symptoms of multiple sclerosis appear in a variety of ways. Most patients first have a single attack of symptoms, a neurological episode called a clinical isolated syndrome, which typically occurs between the ages of 20 and 50. Initial symptoms may be mild enough that patients do not always seek medical care. Once a second attack occurs, the patient is considered to have relapsing-remitting multiple sclerosis. Much less commonly, the disease is progressive from the start, with the patient having more or less continuous symptoms.
Symptoms in multiple sclerosis depend on the location of the nerve lesion. Not all symptoms affect all patients.

EARLY SYMPTOMS

Symptoms more likely to occur earlier in the disease include:
  • Vision Problems. Optic neuritis, inflammation of the nerves in the eye, is a common early symptom in over half of patients. Patients may initially experience blurred or double vision, usually because of problems with one eye. As the condition progresses, vision loss increases, although total blindness is rare.
  • Tingling and Numbness Sensations. Tingling, crawling or burning sensations, or loss of sensation can occur. Patients may feel sensations of intense heat or cold. Symptoms often begin at the end of the legs or arms and move up towards the beginning of the limb. L’Hermmitte’s sign, which is caused by lesions in the cervical spine in the neck, is an electrical buzzing sensation that runs down the back and into the legs. It occurs when bending the neck forward.
  • Muscle Weakness and Spasms. Patients can feel weakness, clumsiness, or heaviness in the limbs. They may have difficulty with finger dexterity. Muscle spasms and stiffness (spasticity), particularly in the legs, occur in an initial attack of MS in about 40% of patients.
  • Problems with Balance and Coordination. Patients have an unsteady gait and difficulty walking normally and keeping their balance. They may have trouble grasping small objects. These problems can be compounded by other common MS symptoms, such as dizziness and tremor. Ataxia (lack of muscle coordination) and tremors (shaking or trembling of limb) affect up to half of patients.
  • Fatigue. Fatigue is the most common and debilitating symptom of MS and often occurs early in the disease. Fatigue is typically worse in the late afternoon and improves in the early evening, and may be accompanied by an increase in body temperature. At the onset, this occurs in about 20% of patients, but as the disease progresses, this is a significant symptom in nearly all patients

OTHER COMMON SYMPTOMS

Other common symptoms that progress over time include:
Bladder and Bowel Problems. Some patients have problems emptying their bladder (urinary retention) and bowels (constipation) or find they cannot control their bladder and bowels (incontinence). Patients with urge incontinence need to urinate frequently or are unable to reach the bathroom before leakage occurs. Bladder problems, and catheterization for urinary retention, can lead to urinary tract infections.
Pain. About two-thirds of patients have pain at some point during the course of the disease, and 40% are never pain free. MS causes many pain syndromes; some occur for a short time while others continue for a long time. Some worsen with age and disease progression. Pain syndromes associated with MS include trigeminal (facial) pain, powerful spasms and cramps, pressure pain, stiffened joints, and a variety of sensations, including feelings of itching, burning, and shooting pain.
Sexual Dysfunction. Sexual dysfunction is a common problem, occurring in more than 70% of patients. Men are likely to have erectile dysfunction, and women often have problems with vaginal lubrication. Sexual dysfunction appears to be highly associated with urinary dysfunction.
Speech and Swallowing Problems. Up to half of patients have trouble chewing or swallowing. Some patients have slurred speech and problems speaking clearly.
Thinking, Concentration, and Memory Problems. Cognitive problems, such as having trouble concentrating, reasoning, and solving problems, affect about half of patients. Up to 75% of patients have problems with memory. These disabilities can create difficulties in the workplace.
Mood Swings. Depression is very common and is sometimes very severe. Depression can be caused both by physical changes in the brain as well as emotional response to the stress of dealing with MS. About 10% of patients suffer from psychosis (manic depression and paranoia). About 5% of patients with severe MS have uncontrolled and extreme mood swings where they alternate between uncontrollable laughing and weeping (pseudobulbar affect).

POSSIBLE SYMPTOM TRIGGERS

Some patients find that MS flares (relapses) are triggered by certain factors. Possible symptom triggers include.
Infections. Viral and bacterial infections, including urinary tract infections, may provoke MS symptoms.
Heat and Cold. Sudden changes in temperature or humidity can trigger symptoms. Many patients with MS have heat intolerance and find that heat worsens their symptoms.
Stress. Many patients report that stress worsens their symptoms.

Prognosis

Multiple sclerosis is not a fatal disease. Except in rare cases of severe disease, most people with multiple sclerosis have a normal or near-normal life span and usually die from the same conditions (heart disease, cancer) that affect the general population. Still, MS symptoms can negatively affect quality of life. Suicide rates among patients with MS are higher than average.
The majority of patients with MS do not become severely disabled. Twenty years after diagnosis, about two-thirds of people with MS remain ambulatory and do not need a wheelchair, although many of them may use a cane or crutches for walking assistance. Some patients use an electric scooter or wheelchair to help cope with fatigue or balance problems.
The severity of the disease, and how the disease progresses, varies widely from patient to patient and is unpredictable. About 20% of patients remain asymptomatic or become only mildly symptomatic after an initial clinical event. Another 20% experience a rapidly progressive condition. Most patients, however, will have some degree of disease progression.
Women tend to have a better outlook than men. Factors that determine a higher risk for a severe condition include:
  • Age over 40 years at the time of onset of symptoms
  • Initial symptoms that affect motor control, mental functioning, or urinary control
  • Initial symptoms that affect multiple regions of the body
  • Attacks in the first years that are frequent, or a short time between the first two attacks
  • Incomplete remissions
  • Rapid progression to disability
  • MS that is progressive from the beginning or becomes progressive shortly after the onset

Causes

As with other autoimmune disorders, the exact cause of MS is unknown. A combination of environmental and genetic factors likely plays a role.

GENETIC FACTORS

Multiple sclerosis is not hereditary, but genetic factors appear to play a role in making some people susceptible to the disease process leading to the condition. The most significant genetic link to MS has been identified in the major histocompatability complex (MHC), a cluster of genes on chromosome 6 that are essential for immune system function. A much smaller percentage of MS cases may be due to variations in interleukin-7 (IL-7) and interleukin-2 (IL-2) gene receptors, which are also related to immune system regulation.

ENVIRONMENTAL FACTORS

Multiple sclerosis is more common in certain geographical areas of the world, particularly areas that are farther from the equator. Prevalence is generally highest in northern European and North America. The clustering of MS cases in these regions has led researchers to investigate whether certain toxins, infections, or vitamin deficiencies (such as vitamin D) may play a factor in triggering MS in genetically susceptible people.
Infectious organisms, mainly viruses, have long been a suspect. They include Epstein-Barr virus (the cause of mononucleosis), herpesvirus 6, herpes simplex virus, influenza, measles, mumps, varicella zoster virus, cytomegaolovirus, respiratory syncytial virus, and Chlamydia pneumonia. However, no direct link has been proven between these infections and multiple sclerosis. There is no evidence that any type of vaccination cause multiple sclerosis.

Risk Factors

About 400,000 Americans and 2.5 million people worldwide suffer from MS.

AGE

Onset occurs between the ages of 20 and 50 years in 70% of patients with the average age about 30. The disease also occurs in both younger and older individuals. It rarely develops before age 15 or after age 60, however.

GENDER

MS is about 2.5 times more common among women than men. The gender gap is strongest among people who develop MS at a younger age. However, some research indicates that men may be more disabled by the disease than women.

RACE AND ETHNICITY

Multiple sclerosis occurs worldwide but is most common in Caucasian people of northern European origin, especially those of Scottish descent.

FAMILY HISTORY

A family history of the disease may put some people at risk for MS, although the risk for someone inheriting all the genetic factors contributing to MS is only about 2 – 4%. Some research indicates that family members who have MS tend to develop the disease at around the same age. However, family history does not predict whether one family member will experience the same disease severity as another family member.

POSSIBLE PROTECTIVE FACTORS

Estrogen and Oral Contraceptives. Higher estrogen levels may temporarily lower the risk of developing multiple sclerosis. Studies indicate that oral contraceptives (which contain estrogen) and pregnancy delay the onset of multiple sclerosis. The risk for a first clinical attack increases, however, in the 6 months after a woman gives birth.

Diagnosis

Most patients first seek medical help after a first attack of symptoms called a clinically isolated syndrome (CIS). Not all patients who have a CIS go on to develop MS, and it is difficult to predict which patients will or will not.
Multiple sclerosis can be challenging to diagnose as there is no one test for it, and a number of other conditions may mimic its symptoms. To confirm a diagnosis of multiple sclerosis the doctor needs to find:
  • Evidence of nerve damage in at least two different areas of the central nervous system (brain, spinal cord, and optic nerves)
  • Evidence that the damage occurred in episodes that happened at least one month apart
  • No evidence that the damage is caused by other conditions
A diagnosis of multiple sclerosis is based on results from a combination of various tests. These include the patient’s medical history, neurological exam, magnetic resonance imaging (MRI) scans, evoked potential tests, and possibly a spinal fluid test.

MEDICAL HISTORY

The doctor will ask about the patient’s personal and family medical history, including lifestyle factors, prescription or other drug use, and other medical conditions that the patient or relatives may have had. The doctor will ask the patient to describe the symptoms experienced, when they occurred, and how long they lasted.

NEUROLOGICAL EXAM

In a neurological exam, the doctor will test the patient’s vision and reflexes and evaluate balance, coordination, and muscle strength.

EVOKED POTENTIAL (EP) TESTS

This is a simple and painless electrical test of nerve function that assesses how long it takes nerve impulses from the eye, ear, or skin to reach the brain. It involves having electrodes placed on the scalp over specific areas of the brain that process sensory information. Evoked potential tests can be used to evaluate nerve transmission for vision, sound, or muscle responses in the legs or arms.

MAGNETIC RESONANCE IMAGING

Magnetic resonance imaging (MRI) scans are important diagnostic tools in MS and are used for diagnosing multiple sclerosis, tracking changes over time, and helping to determine treatment effectiveness.
MRIs scans can detect bright patches that indicate areas of damaged myelin and injured tissue (lesions) caused by MS. However, about 5% of people who are confirmed to have multiple sclerosis based on other diagnostic criteria, do not show evidence of lesions in an initial MRI.
Once diagnosed, periodic follow-up MRIs can be used to track the disease and effectiveness of treatments in two ways:
  • By distinguishing new lesions from old ones
  • Revealing increasing or decreasing numbers of lesions within the central nervous system over time

CEREBROSPINAL FLUID ANALYSIS

A spinal fluid test by itself cannot confirm or exclude multiple sclerosis but it can be useful when combined with other tests. Obtaining a sample of spinal fluid requires a lumbar puncture, or spinal tap. Spinal fluid in patients with MS usually contains unusually high levels of immunoglobulin G (IgG) antibodies as well as other proteins and fragments of myelin. These can be signs of an autoimmune disorder, not necessarily multiple sclerosis.

A lumbar puncture, or spinal tap, is a procedure to collect cerebrospinal fluid to check for the presence of disease or injury. A spinal needle is inserted, usually between the 3rd and 4th lumbar vertebrae in the lower spine. Once the needle is properly positioned in the subarachnoid space (the space between the spinal cord and its covering, the meninges), pressures can be measured and fluid can be collected for testing.

RULING OUT OTHER DISORDERS

The symptoms of MS overlap with a number of other diseases that must be ruled out. These conditions include stroke, alcoholism, emotional disorders, Lyme disease, chronic fatigue syndrome, fibromyalgia, AIDS, cervical spondylosis, certain neurologic degenerative illnesses, transverse myelitis, and certain other autoimmune disorders (hypothyroidism, scleroderma, Sjogren syndrome, vasculitis, and systemic lupus erythematosus).

Because this  NY Times article is old, we are not providing their listing of medications as this report was prepared prior to the Oral Medication

To see the continuation of this article and the resources used, click here
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC’s accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.’s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

A.D.A.M. Copyright
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only — they do not constitute endorsements of those other sites. © 1997- 2008 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

~~~~~~~~~~~~~~~~~~~~
 Keep CURRENT and up to date, with MS News and Information
Sign-up for emails 

.

WATCH OUR MS EDUCATIONAL VIDEOS by Topic, 

.

Visit our MS Learning Channel on YouTube: http://www.youtube.com/msviewsandnews