Myasthenia Gravis (MG) is a rare life-threatening auto immune neuromuscular junction disorder. The name Myasthenia Gravis is derives from Greek (myasthenia = muscle illness) and Latin (gravis = grave) words, together, meaning “grave muscular weakness”. MG is characterized by painless, fluctuating, fatigable weakness involving specific muscle group.
The prevalence of MG is estimated to be about 20/100,000 population in the United States. It occurs in all races, both genders and at any age, but the average age of onset in females is 28; in males, it’s 42. In about 10 percent of cases, MG begins in childhood (juvenile onset). In some cases, the foetus of a pregnant mother with MG may acquire immune antibodies. Congenital Myasthenia is a rare disorder where babies are born with a genetic defect in neuromuscular transmission similar to MG; however, it is not an auto-immune disorder. This is called Neonatal Myasthenia and is generally temporary, with the child’s symptoms often disappearing within few weeks after birth. Some children may develop MG indistinguishable from adults. MG is not directly inherited nor is it contagious. It does occasionally occur in more than one member of the same family.
Generally, the immune system releases antibodies to attack foreign invaders, such as bacteria. In autoimmune diseases, the antibodies mistakenly attack a person’s own tissues. In myasthenia gravis, they attack and damage muscle cells; in Lambert-Eaton myasthenic syndrome, they attack nerve cells that send messages to muscle.
MG can affect any voluntary muscle i.e. skeletal muscle muscles. Involuntary muscles such as the digestive system, heart and brain are not affected. MG tends to affect the muscles that control movement of the eyes and eyelids, causing ocular weakness, facial expression, chewing, talking, and swallowing are often, but not always, involved in the disorder.
Causes
- Muscle Functions
Generally, the brain sends an electrical signal along the motor nerves to the muscle to make movements, during this process, a chemical transmitter – acetylcholine (ACh) is released from the nerve ending. It immediately crosses to the muscle where it
locks onto the ACh receptors (AChR), causing the muscle to contract. The spare ACh
is broken down by ACh esterase, allowing the muscle to relax.
However, in myasthenia gravis the immune system produces antibodies (proteins) that block or damage the muscle acetylcholine receptors, which prevent the muscles contracting. The disruption caused due to this, weakens the muscles.
These antibodies may also block the function of a protein called a muscle-specific receptor tyrosine kinase. This protein is involved in forming the nerve-muscular junction. When antibodies block the function of this protein, it may lead to myasthenia gravis.
- Thymus Gland
Studies suggest that the thymus gland – part of the immune system situated in the upper chest beneath the breastbone, may trigger or maintain the production of the antibodies that block acetylcholine. Thymomas (tumour of the thymus) tend to be noncancerous and occur in 10% of individuals with MG. In 70% of individuals with MG, the thymus contains clusters of immune cells (hyperplasia) that indicate an active immune response.
The exact nature of the relationship between the thymus and MG is still uncertain. It is believed that the abnormal thymus gland may give incorrect instructions to developing immune cells, resulting in auto-immunity and consequently, defective transmission of nerve impulses to muscles.
- Toxic Metals
Heavy metals are metallic elements with a high atomic weight and a density at least five times greater than that of water. Of the 20-plus heavy metals, four– lead (Pb), cadmium (Cd), mercury (Hg), and inorganic arsenic (As)–cause toxicity in humans, even at low levels. Present in toxic waste, they enter the body through the food chain and accumulate in both hard and soft tissue. Other heavy metals, such as nickel, can cause toxicity, but people are less likely to encounter them at toxic levels.
Underlying heavy metal toxicity may contribute to muscle insufficiencies.
- Auto Immune Attack
This factor is always present and is usually connected with the other causes, e.g. mercury and pesticide toxicity and Candida infection can keep the immune system in a state of imbalance, producing auto-immune reactions.
- Other
Symptoms among patient who already have the disease may worsen with some medications, such as beta blockers, calcium channel blockers, quinine, and some antibiotics. Many believe some people have a genetic propensity to developing the disease. The following are known to make symptoms worse:
- Emotional/mental stress
- Illness
- Some medications
- Tiredness
- Very high temperatures
- Muscle relaxants used during surgery
- Aminoglycoside and Quinolone
- Antibiotics like – cardiac anti-arrhythmics, local anesthetics, magnesium salts (including milk of magnesia)
Symptoms
The symptoms of myasthenia gravis can come on suddenly, but it may take some time before the condition is correctly diagnosed. MG symptoms tend to progress over time, usually reaching their worst within a few years after the onset of the disease.
The symptoms of myasthenia gravis include –
- Eye Muscle – The muscles around the eyes are most commonly affected first, as these are constantly used and can quickly tire. This causes drooping of the eyelid, and double vision. In some people, the muscles around the eyes are the only ones affected (when the level of abnormal antibody is low). If symptoms only affect the muscles around the eyes for longer than two years then the condition is unlikely to progress to other muscles. This is known as ocular myasthenia and affects 1 in 6 people with myasthenia gravis.
- Face and Throat Muscle – Muscles around the face and throat are also often affected. Difficulty in swallowing and slurred speech may be the first signs of myasthenia gravis.
- Altered Speaking – Speech may become very soft or nasal, depending on the affected muscles.
- Limited Facial Expressions
- Problems in Chewing – The muscles used for chewing may wear out halfway through a meal, particularly if you’ve been eating something hard to chew.
- Difficulty in Swallowing
- Neck and Limb muscles – MG can affect the muscles of the arms, legs and neck. This can cause mobility problems, such as a waddling gait, head drop and difficulty performing physical tasks such as lifting.
- Other Symptoms –
- Breathing
- Seeing
- Swallowing
- Chewing
- Walking
- Using your arms or hands
- Holding up your head
Diagnosis
The following diagnostic tests will probably be carried out by the GP –
- Blood Test – A blood test may reveal the presence of abnormal antibodies that disrupt the receptor sites where nerve impulses signal the muscles to move.
- Ice Pack Test – If the patient is detected with a droopy eyelid, an ice pack test may be conducted. In this test, a bag filled with ice is placed on the patient’s eyelids for 2 minutes; once the bag is removed an analysis for any signs of improvement in the movement of eyelids is carried out.
- Edrophonium test –This test is usually carried ,out only when other tests have not yet yielded a conclusive diagnosis. Edrophonium chloride (Tensilon, Reversol) or neostigmine (Prostigmin) is injected into a vein – the drug clocks the breakdown of acetylcholine by cholinesterase (cholinesterase inhibitors) and temporarily increases the levels of acetylcholine at the neuromuscular junction – put simply, edrophonium bocks an enzyme that breaks down acetylcholine, the chemical that transmits signals from the nerve ending to the muscle receptor sites. Some patients may experience a brief period in which muscle weakness is relieved, especially those with weakness in the eye muscles.
- Repetitive nerve stimulation – In this test, electrodes are attached to the skin over the affected muscles. Small electrical pulses are sent through the electrodes to measure how well the nerves send a signal to the muscle. The electrical pulses will be applied several times to determine whether signals get worse when the muscle is tired.
- Pulmonary function test (spirometry) – In this test, the aim is to determine whether the patient is breathing adequately. The forced vital capacity (the maximum amount of air a person can expel from the lungs after a maximum inspiration) may be periodically measured so as not to miss a gradual worsening of muscular weakness in the lungs. MG patients with severe symptoms are at risk of respiratory failure due to exhaustion of the respiratory muscles. Respiratory failure is when there is inadequate gas exchange by the respiratory system, with the result that arterial oxygen and/or carbon dioxide levels cannot be maintained within their normal ranges.
- Muscle Biopsy – this is only done if the diagnosis is in doubt and a muscular condition is suspected. A needle or small incision is used to remove a small sample of muscle. The patient will receive a local anesthetic.
- Single-fiber electromyography (EMG) – Electromyography (EMG) measures the electrical activity traveling between your brain and your muscle. It involves inserting a fine wire electrode through your skin and into a muscle. In a single-fiber EMG, doctors test a single muscle fiber.
- Imaging Scans – Doctors at times prescribe CT scan or MRI test to check if there’s a tumor or other abnormality in the thymus.
Treatment
- Medications
- Cholinesterase inhibitors – These inhibitors block the action of the chemical that normally makes the muscle relax after it has contracted. They improve communication between nerves and muscles. This medication is very effective for patients with mild MG symptoms. Some side effects may include nausea and/or stomach cramps.
- Steroids or Immunosuppressant – These help in altering the body’s immune system and lower the production of antibodies that cause MG. This includes – prednisolone (a steroid drug) or azathioprine (an immunosuppressant drug)
- Therapies
- Plasmapheresis – In this therapy blood is removed from the body, the plasma (the abnormal antibodies that cause MG) is separated from the cells, the cells are then suspended in saline (or a plasma substitute or donor plasma), and the reconstituted solution is returned to the patient.
- Intravenous immunoglobulin therapy – In this therapy, normal antibodies that alter the way the immune system acts are injected into the patient.
- Removal of the thymus gland (thymectomy) – About 15 percent of the people with myasthenia gravis have a tumor in their thymus gland, a gland under the breastbone that is involved with the immune system. A thymectomy may be performed as an open surgery or as a minimally invasive surgery.
Alternative Treatment
Environmental Medicine is a branch of medicine whose domain is not limited by anatomical boundaries but, rather, is concerned with the whole person and the way that a person reacts to his/her total environment. It involves treating the cause of the disease. In MG, the treatment involves –
- Herbs – Herbs like Liquorice and Kallawala (Polypodium leucotomos) can insignificantly turn off the auto-immune destructive reactions that maintain the disease. Also, colloidal silver (used to fight the infections) has some immune regulatory and healing effect. These herbs act as repairing agents for the immune system.
- Thymus Treatment – Herbs like Echinacea, yarrow, thyme, barley grasslicorice, olive leafpau d’arco rosehips, wheatgrass help in keeping the thymus gland strong and enhances its immunity. Cruciferous vegetables like broccoli, cauli flower, cabbage etc. also appear to enhance thymus function, as do the essential oils of bergamot,clove, tea tree, oregano, thyme and eucalyptus, Nutrients like black current oil, organic germanium, vitamin A and beta carotene and zinc helps the thymus function.
- Biodetoxification Program – The Center’s Bio-detoxification Program utilizes clinical procedures that safely reduce the body’s burden of toxic chemicals, including chemicals stored following occupational, accidental, and/or chronic airborne exposures.
- Alka Vita Supplements – This has the tremendous advantage that it alkalises, therefore increases oxygenation, counteracts free radical attack and damage and therefore undermines the basis of disease. It is also directly ‘anti-septic’ against fungal infections, including Candida and possibly all harmful micro-organisms and parasites, although there is not enough information on this, we do know that all anaerobic infections (the harmful ones) are attacked by free electrons that Alka- vita supplies and are eventually destroyed or severely limited by an alkaline environment.
- Colloidal Silver – Eliminates infections of various types, known and unknown that contribute to auto-immune disorders leading to the improper function of the immune function.
- Vitamin Supplements -Different Vitamins are essential to aid the immune system and many biochemical processes including the utilisation of calcium and magnesium. Its deficiency is almost universal in northern climates and even more so since the introduction of sun screen. Its deficiency has been linked strongly to auto-immune diseases.
- Omega 3 Fatty Acids – For improving the body function.
- Exercise – Helps to –
- Increase flexibility
- Improve range of motion of your joints
- Boost circulation
- Promote better posture
- Relieve stress
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