Western Medicine

Myasthenia gravis is a chronic disorder of neuromuscular junction function that causes muscles to become weak and to tire easily. The specific pattern of muscle involvement is often important to diagnosis.

The Brain and Nervous System

The central nervous system comprises the brain and spinal cord. Nerves are attached to the spinal cord and branch out to the entire body forming the peripheral nervous system. Nerve impulses can travel along each nerve in one direction only. One type of nerve (motor) carries signals from the brain to the legs, for example, and another (sensory) sends signals back from the legs to the brain.
(Reader's Digest, Guide to Medical Cures and Treatments copyright 1999)

Chinese Medicine

Myasthenia gravis is an autoimmune disease that results in chronic defective transmission of nerve impulses to the muscles. The disease produces weakness and abnormally rapid fatigue of voluntary muscles. Symptoms improve after rest or medication. The disease usually presents between the ages of 10 and 50 years and women are affected more often than men in 200,000. It is an uncommon disease occurring in approximately one in 200,000 people.
Depending on the symptoms it produces, myasthenia gravis is placed in different traditional Chinese medicine (TCM) syndrome categories:

• When weakness of the limbs predominates, it is classified as flaccidity syndrome. In TCM, this refers to a syndrome marked by weakness, limited movement and muscular atrophy (wasting) of the limbs, especially the lower limbs and results from lack of nourishment reaching the muscle tissue. This can be caused by consumption of body fluid by lung-heat, an overwhelming effect of dampness-heat evil, or weakness of the liver and kidneys leading to insufficiency of essence and blood.
• If the main symptom is drooping of one or both eyelids, the syndrome is classified as ptosis.
• In individuals presenting with weakness of the eye muscles and suffering from double vision, the syndrome is classified as vision changes.
• Others classifications include drooping head or respiratory collapse and relate to corresponding manifestations of the disease.

Western Medicine

Myasthenia gravis has an overall incidence of about four cases per million. There is no racial or geographic predilection, and the disorder can occur at any age. However, there is an increased incidence in young women, especially in the third decade, and in older men in the seventh decade.
The disease is caused by the autoimmune destruction of the acetylcholine receptors on the post-synaptic membrane of the muscle fiber. Immune complexes are deposited at the post-synaptic membranes causing interference with and later destruction of the acetylcholine receptor. The communication between the nerve impulses and muscle fibers is impaired or lost and muscle weakness results.

Click here to see structure of the Neuromuscular Junction
The process that initiates the immune response is unknown, but the thymus gland appears to be critical for both the autoimmune activation and the maintenance of the activated autoimmune state. Overgrowth of the thymus gland is found in 70 per cent of myasthenic patients below the age of 40 years. In 10 per cent of patients there is a tumor of the thymus gland and the incidence of this increases with age.
There is an association between myasthenia gravis and thyroid disease, rheumatoid disease, pernicious anemia and systemic lupus erythematosus. Myasthenia gravis is sometimes caused by D-penicillamine treatment in rheumatoid disease.

Chinese Medicine

Click here to see the causes of myasthenia gravis from a TCM perspective
In TCM, myasthenia gravis is considered to be a complex disease. Many organs or systems of the body are involved and progress of the disease varies. Manifestations of the disease do not necessarily follow a prescribed order, but depend on the pathogenic factors involved and the mechanisms affected. The causes can be classified as follows:
Exogenous causes
Invasion by exogenous pathogens leads to impaired functioning of organs and depletion of blood and vital energy (qi), contributing to the disease. TCM considers that blood belongs to yin-fluid, which is mainly responsible for providing moisture and nourishment to the tissues. The role of qi is to promote and consolidate all body functions. Deficiency in blood and qi result in inadequate supply of these essentials to the muscles, tendons and meridians and flaccidity syndrome results.
Endogenous causes
These can occur when an individual encounters emotional problems or damage by the seven modes of emotions (for example, anger damaging the liver, fear damaging the kidneys or melancholia damaging the spleen). The understanding in TCM is that the liver stores the blood that supports the tendons, and the kidneys store essence for the production of bone marrow. Both blood and essence are part of yin. If an individual's liver-yin and kidney-yin are depleted, a virtual fire is created internally causing the supply of blood and essence to become exhausted. The tendons and muscles then lose their nutrient supply and become weak and numb.
Non-exogenous/endogenous cause
This is mainly the result of an imbalanced lifestyle and includes the eating of an improper diet (too much greasy or sweet food) or excess consumption of alcohol and leads to spleen and stomach injury. Stress and chronic disease can also result in a decline in qi and body fluid and cause spleen and stomach damage. The spleen and stomach are the primary organs for digestion and absorption; they extract nutritive essence from food and use it for the production of qi, blood and body fluids. If they do not function properly, muscle weakness, drooping eyelids or breathing difficulties can develop.
Congenital factors
Inborn defects, such as weakness of the spleen and stomach, yang-deficiency of the spleen and kidneys or yin-deficiency of the liver and kidneys, can cause failure in different organs and lead to the disease.

Western Medicine

Weakness is the defining symptom of myasthenia gravis. Patients may not recognize it as such and complain to their doctor of double vision, difficulty swallowing, slurring of speech, or even a change in gait. Five areas of motor function are commonly affected and involve the muscles that control the following:

• the eye
• the face, nose and throat
• respiration
• the torso (pectoral and pelvic muscles), and
• the arms and legs.

The symptoms may fluctuate from hour to hour, from day to day, or over longer periods. They are provoked or worsened by exertion, exposure to extremes of temperature, viral or other infections, menses and excitement.

The symptoms experienced are commonly these:

• Eye muscle involvement often results in drooping of the upper eyelid and double vision. It usually affects both eyes and is asymmetrical.
• Weakness of other muscles innervated by cranial nerves results in loss of facial expression, everted (pouting) lips, a smile that resembles a snarl, jaw drop, nasal regurgitation of liquids, choking on foods and secretions, and a slurred, nasal speech with a reduced volume.
• Depending on the severity of the disease, difficulty breathing can appear on moderate or mild exertion or be present even at rest.
• Abnormal tiredness of the limb muscles causes difficulty in combing the hair, lifting objects repeatedly, climbing stairs, walking and running.

Drooping of the eyelids is an early symptom of myasthenia gravis.

Initially, the symptoms affect only the eyes in 40 per cent of patients; are generalized in 40 per cent; involve only the extremities in 10 per cent; and affect only the nose, mouth or throat, or these muscles and the eye muscles in another 10 per cent. Subsequently, the weakness can spread from the eye to the facial, salivary, swallowing and respiratory muscles and then to the torso and limb muscles, but the sequence may vary. Arm and leg muscles are affected more than hands and feet. In the most advanced cases the weakness is general throughout the body.
By the end of the first year, the eye muscles are affected in nearly all patients. The symptoms remain ocular (involving the eye) in only 16 per cent. In nearly 90 per cent of those in whom the disease becomes generalized, this occurs within the first year after the onset. Progression is most rapid within the first three years, and more than half of the deaths caused by myasthenia gravis occur in that period.
Spontaneous remissions lasting from weeks to years can occur. Long remissions are uncommon, and most remissions occur during the first three years.

Chinese Medicine

TCM practitioners will examine a sufferer and categorize symptoms under special syndrome groups known as "disharmony patterns." Certain disharmony patterns are present at different stages of a disorder. In myasthenia gravis, these can be classified into the following types:

Qi-deficiency in the spleen and stomach
Individuals present with drooping eyelids, weakness of the limbs, and difficulty in holding the head up and chewing food. Symptoms are worse towards the end of the day. Others symptoms include poor appetite, diarrhea, a reluctance to speak and shortness of breath.
Yang-deficiency in the spleen and kidneys
This often presents with drooping eyelids, limitation in muscular control of the eye, and limb weakness. Other accompanying symptoms are soreness in the loin region, spontaneous sweating, aversion to cold temperatures, cold limbs, a pale complexion, difficulty in swallowing, poor appetite and diarrhea, and the excretion of large volumes of dilute urine.
Yin-deficiency in the liver and kidneys
The main symptoms include drooping eyelids, difficulty in swallowing and chewing food, and limb weakness. Symptoms worsen towards the end of the day. Other accompanying symptoms are soreness and weakness in the lumbar (lower back) region and knees, dizziness, ringing in the ears, insomnia and nightmares. A feeling of dryness in both eyes and a hot sensation in the chest, palms of the hands and soles of the feet can develop.
Deficiency in both qi and blood
Individuals present with fatigue and weakness, palpitation, shortness of breath, a reluctance to speak, pale complexion, drooping eyelids, difficulty in swallowing and chewing food, muscle wasting and fatigue, and spontaneous sweating.

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Western Medicine

The presence of weakness (usually worse at the end of the day or after vigorous exercise), but without loss of sensation is necessary although not sufficient on its own to make the diagnosis of myasthenia gravis. Diagnosis is based on the clinical history, physical examination and results of specific tests and laboratory studies.

Tensilon (edrophonium) test
Edrophonium chloride (an anticholinesterase) is given intravenously. If improvement in weakness occurs within seconds and lasts for two to three minutes the test is considered positive. Occasionally the test itself can cause respiratory constriction and fainting and is always carried out in a proper clinical setting.
Serum acetylcholine receptor antibodies
These disease-specific antibodies are present in 90 per cent of cases of generalized myasthenia gravis. The antibodies are found in no other condition.
Nerve stimulation
Stimulation of the motor nerve results in a characteristic decrease in muscle response.

Other tests
Chest X-ray may show a mass (enlarged gland) in the area of the thymus that can be confirmed by computed tomography scanning. Nothing unusual can be detected from peripheral blood samples.

The thymus gland lies behind the breastbone and extends upwards as far as the thyroid. It has an immunological role. Autoimmunity in myasthenia gravis is thought to result from pathological activity in this gland.

Chinese Medicine

Diagnosis in TCM places importance on determining the circumstances and manifestations of a disease through inquiry and symptom observation. Diagnosis is based on the traditional four examination techniques:

1. Questioning The TCM practitioner will establish the medical history of both the patient and his family.
2. Observation Examination of the physical features of the body, such as the face, tongue, hair, nails, sputum (mucus that is coughed up), and location of pain, all offer clues to the problem. The tongue is a particularly useful indicator of the functioning of the internal organs.
3. Listening and smelling The smelling of sputum and breath and listening to the sounds produced by the chest offer additional clues to the patient's health.
4. Touching Feeling the pulse is a cornerstone of TCM diagnosis and gives the practitioner much information about any bodily imbalance.

In myasthenia gravis, the procedures used in TCM to differentiate between disharmony patterns can be explained as follows:

Qi-deficiency in the spleen and stomach
Impaired functioning of the spleen and stomach causes an insufficiency in qi and blood production. This reduces the supply of nutrients available to the muscles and tendons and results in weakness in muscular contractions. A reluctance to speak and shortness of breath also result from qi and blood insufficiency. Poor appetite and diarrhea are symptoms of spleen weakness.
On examination, the tongue is swollen, pink in color, indented on the margins and coated with a thin, white fur. The pulse is weak and fine.

Yang-deficiency in the spleen and kidneys
Yang-deficiency implies under-functioning of these two organs. This leads to a decline in the storage of essence and muscle weakness results. Kidney-yang deficiency also causes soreness in the loin area, production of copious amounts of dilute urine and an aversion to cold temperatures.
On examination, the tongue is swollen, pink in color and covered with a thin, white fur. The pulse is deep and fine.

Yin-deficiency in the liver and kidneys
Yin-deficiency of these organs leads to essence and blood depletion and results in loss of nourishment and moisture to the body. Body structures, such as the muscles, bones and tendons, become weak. Liver-yin deficiency can also cause insomnia, nightmares and dryness of the eyes. Kidney problems cause dizziness, ringing in the ears, soreness and weakness in the loin area and the knees.
On examination, the tongue is red with a scanty fur covering. The pulse is fine and rapid.

Deficiency in both qi and blood
Deficiency in qi and blood not only affects the supply of nutrients to muscles and tendons, but also leads to general impairment of the whole body. In addition to symptoms of muscle weakness, individuals present with fatigue, palpitation, shortness of breath, pallor and spontaneous sweating.
On examination, the tongue is pale, swollen and indented on the margins. The tongue fur is white and thin. The pulse is deep and fine.

The muscles of the human body (Illustrated Explanations of the New Medicine, 19-20th century)

Western Medicine

Therapy for myasthenia gravis can be divided into four groups: symptomatic treatment; immunosuppressive medication; short-term immunosuppressant treatment; and surgical thymectomy (removal of the thymus gland).

Symptomatic treatment
The anticholinesterase drugs (such as pyridostigmine and neostigmine) improve strength by improving neuromuscular junction transmission without altering the autoimmune disorder. They are therefore useful only to lessen symptoms and are usually used in combination with another form of more substantive treatment. High doses of anticholinesterases can cause paradoxical weakness and be confused with a worsening of the symptoms of the disease.

Immunosuppressive medication
Prednisone and azathioprine remain the main immunosuppressive agents used in the treatment of myasthenia gravis. The choice of agent depends on the goals of therapy.

Prednisone (a corticosteroid) given daily in a high dose is both effective and rapid in onset of action. It carries however both short- and long-term potential side effects. Additionally, high-dose daily corticosteroids can cause a transient, potentially severe exacerbation of weakness in about a quarter of patients during the first week of treatment. In this situation, the drug is then often given on alternate days only.

Azathioprine is an effective drug but usually requires three to 12 months of use prior to the onset of a therapeutic benefit. It can be used alone in mild cases or added as a steroid-sparing drug to allow the dose of prednisone to be reduced. The main complications involve bone marrow suppression and altered liver function.

Cyclosporine has only recently been introduced in the treatment of myasthenia gravis. It is used in cases that do not respond to conventional treatment and for those intolerant of corticosteroids. It can affect kidney function and cause high blood pressure.

Short-term immunosuppressant treatment Short-term immunosuppressant treatments include plasma exchange and intravenous gamma globulin. Both promote rapid improvement in muscle weakness. Although these treatments are known to alter the function of the immune system, the actual mechanism of action is not clear. They are mainly used in myasthenic crisis, other less severe exacerbations of the disease and preparation of a weak patient for thymectomy. Both are expensive, but they have a limited role in maintenance therapy in some patients.

Surgical thymectomy
Thymectomy is considered the only therapy for myasthenia gravis that offers a significant chance for a drug-free remission. Additionally, the procedure is essential in those patients with thymomas for removal of the growth. Early surgical removal of as much of the thymus gland as possible appears to offer the best therapeutic benefits.

For most patients with pure ocular (eye) or very mild generalized myasthenia gravis, symptomatic treatment alone is enough. Occasionally, the disabling symptom of double vision will necessitate the use of immunosuppressive drugs, but for the most part these medicines are reserved for significant generalized disease.

Surgical thymectomy is usually indicated as the first line of treatment for patients with significant generalized myasthenia gravis between puberty and about 50 years of age, as well as all patients with a thymoma.

Patients with late-onset generalized myasthenia gravis frequently have marked difficulty with swallowing and breathing; high-dose corticosteroids are consequently often needed to prevent aspiration and/or respiratory insufficiency.

Chinese Medicine

There are three therapeutic options in the TCM treatment of myasthenia gravis: the regularization of disharmony patterns, use of Chinese patent medicines and acupuncture therapy.

Therapeutic regimens for disharmony patterns

Qi-deficiency in the spleen and stomach

Therapeutic aim: To Tonify the spleen and benefit the qi

Prescription: Buzhong yiqi decoction (modified)

In this prescription, pilose asiabell, milk-vetch and large head atractylodes roots are used to tonify the spleen and benefit the qi. Cimicifuga rhizome and Chinese thorowax root improve the transformation and transportation functions in the spleen. Dried tangerine peel regulates the qi movement; Chinese angelica aids the blood; and fresh ginger and Chinese date improve the communication between the interior and exterior of the body. Coix seed and Indian bread invigorate the spleen and expel dampness evil. Used in combination, these ingredients invigorate the spleen and stomach, increasing production of nutrient essence and relieving symptoms.

Yang-deficiency in the spleen and kidneys

Therapeutic aim: To warm and tonify the spleen and kidneys

Prescription: Yougui bolus (modified)

In this prescription, monkshood, cassia bark and deerhorn glue warm and invigorate the spleen and kidneys. Rehmannia root, Asiatic cornelian cherry, dodder seed, wolfberry and eucommia are used for nourishing the spleen-yin and kidney-yin. Chinese angelica replenishes the blood; and pilose asiabell, milk-vetch, common yam and large head atractylodes roots replenish the qi and tonify the spleen.

Yin-deficiency in the liver and kidneys

Therapeutic aim: To nourish and invigorate the liver and kidneys

Prescription: Zuogui bolus (modified)

In this prescription, fresh rehmannia rhizome is used in quantity for effective nourishment of the kidney-yin. Wolfberry replenishes the essence and improves visual acuity; and Asiatic cornelian reduces depletion of essence and calms the liver. Deerhorn glue invigorates the yang; and tortoise shell glue nourishes the yin. A combination of these two glues can replenish essence and bone marrow. Dodder seed and achyranthes root reinforce the lumbar (lower back) region and knees, and strengthen the tendons and bones. Common yam root tonifies the spleen and aids the kidneys.

Deficiency in both qi and blood

Therapeutic aim: To invigorate and replenish the qi and blood

Prescription: Bazhen decoction (modified)

In this prescription, ginseng, Indian bread, large head atractylodes root and liquorice root invigorate the spleen and benefit the qi. Pilose asiabell, white peony and rehmannia roots nourish the heart and blood. Szechwan lovage root improves the blood circulation; when combined with pilose asiabell root and rehmannia root, it increases blood production without causing an increase in viscosity (thickening). Fresh ginger and Chinese date help the ginseng and Indian bread to regulate the spleen and kidneys.

Chinese patent drugs
These drugs are available in small dosages and are readily absorbed on ingestion. They are more convenient to use because they are not bulky to carry about and are therefore more appropriate to a busy lifestyle. Taking a pill or a bolus is often easier for those who do not wish to consume large volumes of liquid or who do not like the bitter taste of decoctions. Examples of patent medicines used in the treatment of myasthenia gravis are:
Qi-deficiency in the spleen and stomach: Buzhong yiqi bolus
Yang-deficiency in the spleen and kidneys: Ginseng yangrong bolus
Yin-deficiency in the liver and kidneys: Liuwei dihuang bolus
Deficiency in both qi and blood:
Jinkui shenqi bolus
Acupuncture therapies
Use of acupuncture stimulates the meridians. These connect the internal organs with the limbs and their stimulation results in:

• activation of qi and blood
• regulation of yin and yang
• strengthening of the tendons and bones, and
• lubrication of the joints.

Acupuncture can be used therefore as the main or an adjuvant therapy.

Acupuncture

General method of acupuncture
Treatment is given daily over 10 days; four to five acupoints are selected each time and the needle retained for 20 to 30 minutes.

For drooping eyelids, acupoints are selected on the face: zan-zhu, yang-bai, yu-yao, si-bai and jing-ming.

For limb weakness: he-gu, nei-guan, wai-guan, san-yin-jiao, tai-chong, da-zhui, pi-yu, shen-yu and zu-san-li are used.

Otopuncture therapy
This therapy is used weekly and applied to each ear alternately. The method involves acupoint embedding of the needle under the skin.
The acupoints used are spleen, kidney, liver and points for endocrine functions.

Western Medicine

Early treatment may improve the chance of a drug-free remission, but prevention is not possible.

Chinese Medicine

In the prevention of myasthenia gravis, or the mitigation of its affects, the following measures are recommended:

Exercise regularly to strengthen body resistance.

Maintain a balanced lifestyle and avoid stress in order to prevent pathogen invasion or induction of attacks.

A balanced lifestyle reduces stress and strengthens the immune system.

Consult your doctor immediately if you experience significant muscle fatigue.

Get regular check ups.

Be wary of any medicine that affects nerve impulses to the muscles or inhibits respiratory movement. Such drugs include certain antibiotics, morphine, curare and quinine.

Dietary therapy may be helpful. Chinese physicians recommend foods that are able to nourish and invigorate the spleen and kidneys, and thus benefit the qi and the blood. Foods such as Chinese date, lotus seed, walnut, Chinese yam, dried mushrooms, wolfberry and fleece flower root can be added to the diet. In individuals who are mainly qi-deficient, milk-vetch root (huang qi) tea (100g boiled over one hour) can be beneficial.

Physicians recommend foods such as Chinese dates, lotus seeds and walnuts for those with myasthenia gravis.

Western Medicine

Chinese Medicine