Inclusion Body Myositis – Prognosis, Symptoms, Treatment, Causes

What is Inclusion Body Myositis?

Inclusion Body Myositis or IBM is what is medically termed as an inflammatory muscular disease. It is characterized as a progressive muscle wasting and weakness. Persons aging 50 years or more are the people who are often affected by this disease condition. These are a very rare condition that occurs and is reportedly seen most on women than in men. Although this said muscular disease condition can be seen during adulthood.

Observe Muscle wasting of both thighs

Causes of IBM

The exact etiology of Inclusion Body Myositis is still unknown. Yet there are theories with regards to the causative factors, such as:

Autoimmune disease

Researchers theorized that it is a form of autoimmune disorder wherein the immune system is in constant fight of the infection until it disappears. Hence, by mere fighting of the immune system, aside from it destroys the virus; it also destroys healthy tissues and putting a bigger risk for the person’s health. It is the mere fact of the patient’s body attacking its own muscular tissues causing swelling and inflammation within the person’s muscular system.

Degenerative disease

Another theory is that it is a degenerative kind of disease wherein the degeneration or atrophy and aging process of the person’s muscles leads to an abnormal buildup and damage of protein.

Medication

Another theory suggested that this disease condition called Inclusion Body Myositis or sometimes called as Sporadic Inclusion Body Myositis is due to the fact that the person takes medication that his or her body is allergic to. Aside from that certain medications made available to the public can cause Inclusion Body Myositis. Some of these medications include cholesterol- lowering drugs, penicillamine, carticaine, interferon-alpha, growth hormones, carbimazole, cimetidine, phenytoin, hepatitis B vaccine. The medications mentioned all contribute to developing Inclusion Body Myositis. It is only through stopping the intake of such medications that the symptoms are relieved.

Genetics

It is believed that one of the causative factors that predispose a person to the said disease condition is the fact that he or she has the gene mutations in the UDP-N-acetylglucosamine 2-epimerase/N-acetylannosamine kinase (GNE) gene. With this gene mutation, it is theorized that the gene impairs the function of the GNE protein leading to having this kind of muscular disease condition.

Infections, Injuries and Viruses

These are other causative factors that contribute to the Inclusion Body Myositis. Acquiring an injury into the patient’s muscles, such as a sport incident or a car accident, may lead to inflammation and edema of the muscular tissue. Viruses, on the other hand, trigger the autoimmune Inclusion Body Myositis symptoms. Persons who are HIV positive can lead to the development of this muscular disease condition.

Symptoms of IBM

When a person has been diagnosed with having Inclusion Body Myositis, he or she will manifest the following symptoms:

1. Muscle weakness that slowly progresses in a matter of months or years
2. History of Frequent falls
3. Dysphagia or having difficulty swallowing
4. Limb weakness
5. Head drop or difficulty holding the head up
6. Muscle wasting
7. Mild facial weakness
8. Increase in difficulty in the day to day task that requires the usage of the muscles located in the proximal area, such of these tasks includes combing the hair, lifting objects, climbing steps, getting up from a chair and stepping onto the curb.
9. Poor grip
10. Pain or discomfort as muscles weaken
11. Weakness is asymmetrical
12. Diminishing DTR or deep tendon reflexes
13. Mixed neurogenic and myopathic changes on electromyography
14. Weakness in the patient’s fingers, wrist, thighs and forearms.

The symptoms mentioned may vary from person to person.

Diagnosis of IBM

The person is thoroughly physically examined by a physician along with questioning related questions with the disease condition and also letting the person take test to confirm the diagnosis. Such of these tests includes the following:

1. Muscle biopsy
2. Blood Test
3. MRIs or magnetic resonance imaging
4. EMGs or electromyography
5. Nerve conduction studies
6. Lab results of Serum creatinine kinase which is less than 12 times the normal

Additional laboratory values that are considered elevated with this kind of disease condition includes:

1. Serum aldolase
2. Serum lactate dehydrogenase
3. Serum alanine aminotransferase
4. Serum aspartate aminotransferase

Aside from that to be diagnosed with this kind of disease condition, one must possess the following clinical features or criteria:

1. Onset age of greater than thirty years old
2. Illness duration which is greater than six months
3. And some of the symptoms that were mentioned above.

It is often misdiagnosed as polymyositis and the person is diagnosed with this one if the patient doesn’t respond to the therapy intended for polymyositis.

Treatment of IBM

When a person has this disease condition, he or she together with his or her physician will work towards the goal of the treatment. The treatment goal focuses on the muscle strength improvement in order to improve the activities of the daily living or ADLs. One must also know that when one is diagnosed to having this muscular disease condition, there will be no treatment that can slow or stop the disease progression.

Immunosuppressants. The specific therapy for this kind of disease condition includes immunosuppressive therapy or treatment.

Intravenous globulin or steroids. Corticosteroids or steroids for that matter help in the regulation of the immune and inflammatory response.

There is also a need for multidisciplinary treatment approach for:

1. Speech and language therapy in the dysphagia assessment
2. Physiotherapy and occupational therapy
3. Dietary support since the patient is at risk for choking due to dysphagia

Prognosis of IBM

According to studies, when one is diagnosed with having Inclusion Body Myositis, there is actually a slow progression when this kind of muscular disease condition is manifested in adulthood. However, if the symptoms are manifested in old age, the muscular disease condition tends to progress in a rapid manner. When one has progressive dysphagia, there is a poor prognosis of the patient.