Myasthenia gravis . Multiple sclerosis K R.ppt

1. IMMUNOLOGY
(AUTOIMMUNE DISEASES)
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2. 1. Myasthenia gravis
Myasthenia gravis (MG) is a chronic autoimmune
disorder in which antibodies destroy the
communication between nerves and muscle,
resulting in weakness of the skeletal muscles.
Myasthenia gravis affects the voluntary muscles of
the body, especially those that control the eyes,
mouth, throat and limbs.
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3. EPIDEMIOLOGY
• MG occurs in all ethnic groups and both sexes. It most
commonly affects women under 40 and people from 50 to 70
years old of either sex, but it has been known to occur at any
age. Younger people rarely have thymoma. Prevalence in the
United States is estimated at between 0.5 and 20.4 cases per
100,000, with an estimated 60,000 Americans affected. Within
the United Kingdom, an estimated 15 cases of MG occur per
100,000 people.
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4. CAUSES
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6. Signs and symptoms
• The hallmark of myasthenia gravis is muscle weakness
that worsens after periods of activity and improves after
periods of rest. Certain muscles such as those that
control eye and eyelid movement, facial expression,
chewing, talking, and swallowing are often (but not
always) involved in the disorder.
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7. Continued…..
People with myasthenia gravis may experience the following
symptoms:
•weakness of the eye muscles (called ocular myasthenia)
•drooping of one or both eyelids (ptosis)
•blurred or double vision (diplopia)
•a change in facial expression
•difficulty swallowing
•shortness of breath
•impaired speech (dysarthria)
•weakness in the arms, hands, fingers, legs, and neck.
•Sometimes the severe weakness of myasthenia gravis may
cause respiratory failure, which requires immediate emergency
medical care.
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10. DIAGNOSIS
A doctor may perform or order several tests to confirm the diagnosis
of myasthenia gravis:
•A physical and neurological examination. A physician will first review
an individual’s medical history and conduct a physical examination. In
a neurological examination, the physician will check muscle strength
and tone, coordination, sense of touch, and look for impairment of eye
movements.
•An edrophonium test. This test uses injections of edrophonium
chloride to briefly relieve weakness in people with myasthenia gravis.
The drug blocks the breakdown of acetylcholine and temporarily
increases the levels of acetylcholine at the neuromuscular junction. It
is usually used to test ocular muscle weakness.
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11. • A blood test. Most individuals with myasthenia gravis
have abnormally elevated levels of acetylcholine
receptor antibodies. However, in some individuals with
myasthenia gravis, neither of these antibodies is present.
These individuals are said to have seronegative (negative
antibody) myasthenia.
• Electrodiagnostics. Electrodiagnosis (EDX) is a method
of medical diagnosis that obtains information about
diseases by passively recording the electrical activity of
body parts (that is, their natural electrophysiology) or by
measuring their response to external electrical stimuli
(evoked potentials).
• Diagnostic imaging. Diagnostic imaging of the chest
using computed tomography (CT) or magnetic resonance
imaging (MRI) may identify the presence of a thymoma.
• Pulmonary function testing. Measuring breathing
strength can help predict if respiration may fail and lead
to a myasthenic crisis.
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12. TREATMENT
There is no cure for myasthenia gravis, but it is treated with
medications and sometimes surgery.
• Medications: Cholinesterase inhibitors (anticholinesterase) boost
signals between nerves and muscles to improve muscle strength.
Immunosuppressants, including corticosteroids, decrease
inflammation and reduce your body’s production of abnormal
antibodies.
• Monoclonal antibodies: You receive intravenous (IV) infusions of
biologically engineered proteins. These proteins suppress an
overactive immune system.
• Plasma exchange (plasmapheresis): An IV line removes
abnormal antibodies from your blood.
• Surgery: A thymectomy is surgery to remove the thymus gland.
Even if tests don’t show a problem with your thymus gland,
surgical removal sometimes improves symptoms.
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13. 2. Multiple sclerosis
• Multiple sclerosis (MS) is an autoimmune disease and
potentially disabling disease of the brain and spinal cord
(central nervous system).
• In MS, the immune system attacks the protective sheath
(myelin) that covers nerve fibers and causes
communication problems between your brain and the
rest of your body. Eventually, the disease can cause
permanent damage or deterioration of the nerves.
• Signs and symptoms of MS vary widely and depend on
the amount of nerve damage and which nerves are
affected.
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17. ETIOLOGY
• EtiologyIt is a disease of young adults. Most
cases occur between the age of 20 and 40
years.Females are affected more than males.
• The cause of disease is unknown; may interplay
between a viral infection, host immune response
and hereditary alone or in combination may play a
role.
• Breach in blood brain barrier in genetically
predisposing individual would be responsible for
MS.
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19. The most common early symptoms of MS are:
• Fatigue
• Vision problems
• Tingling and numbness
• Vertigo and dizziness
• Muscle weakness and spasms
• Problems with balance and coordination
Other, less common, symptoms include:
• Speech and swallowing problems
• Cognitive dysfunction.
• Difficulty with walking
• Bladder and bowel dysfunction
• Sexual dysfunction
• Mood swings, depression
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20. TYPES OF MS
• The disease has several forms which change the course of the
management and are therefore important to recognize. Most
patients will have a months-long to year-long disease free
after their first exacerbation.
• Relapsing remitting disease: progression is characterized by
relapses of active disease with incomplete recovery during
periods of remission.
• Secondary progressive disease: progression becomes more
aggressive so that a consistent worsening of function occurs.
• Primary progressive disease: symptoms are progressive from
the onset of disease with the early onset of disability.
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23. DIAGNOSIS
A doctor will carry out a physical and neurological examination,
ask about symptoms, and consider the person’s medical history.
•No single test can confirm a diagnosis, so a doctor will use
several strategies when deciding whether a person meets the
criteria for a diagnosis.
•These include:
•MRI scans of the brain and spinal cord, which may reveal
lesions
•spinal fluid analysis, which may identify antibodies that suggest
a previous infection or proteins consistent with a diagnosis of
MS.
•an evoked potential test, which measures electrical activity in
response to stimuli
•Other conditions have symptoms that are similar to those of
MS, so a doctor may suggest other tests to assess for other
possible causes of the person’s symptoms.
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24. TREATMENT
There is no cure for multiple sclerosis. Treatment typically focuses on
speeding recovery from attacks, slowing the progression of the disease
and managing MS symptoms. Some people have such mild symptoms
that no treatment is necessary.
Treatments for MS attacks
•Corticosteroids, such as oral prednisone and intravenous
methylprednisolone, are prescribed to reduce nerve inflammation.
Side effects may include insomnia, increased blood pressure, increased
blood glucose levels, mood swings and fluid retention.
•Plasma exchange (plasmapheresis). The liquid portion of part of your
blood (plasma) is removed and separated from your blood cells. The
blood cells are then mixed with a protein solution (albumin) and put
back into your body. Plasma exchange may be used if your symptoms
are new, severe and haven't responded to steroids.
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25. Treatmentsto modifyprogression
Injectable treatments include:
•Interferon beta medications.These drugs are among the most
commonly prescribed medications to treat MS. They are
injected under the skin or into muscle and can reduce the
frequency and severity of relapses.
•Side effects of interferons may include flu-like symptoms and
injection-site reactions.
•Glatiramer acetate (Copaxone, Glatopa). This medication may
help block your immune system's attack on myelin and must be
injected beneath the skin. Side effects may include skin irritation
at the injection site.
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26. TreatmentsforMSsignsandsymptoms
Physical therapy for multiple sclerosis
Physical therapy can build muscle strength and ease some of the
symptoms of MS.
Physical therapy. A physical or occupational therapist can teach
you stretching and strengthening exercises and show you how to
use devices to make it easier to perform daily tasks.
Muscle relaxants. You may experience painful or uncontrollable
muscle stiffness or spasms, particularly in your legs. Muscle
relaxants such as baclofen (Lioresal, Gablofen), tizanidine
(Zanaflex) and cyclobenzaprine may help.
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28. Refrences
• Myasthenis gravis and disorders by Henry j
kaminski and Linda l kusner.
• Autoimmune diseases – Noel R.Rose, Ian
R.Mackay
• Myoclinic.com
• Research gate.com
• Wikipedia.com
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