An inclusion body myositis (IBM) is a progressive muscle disorder causing muscle weakness, weakness, and wasting. Usually, IBM affects adults over 50, and it is more common in men than women. It mainly affects the muscles of the arms and legs, but it can also affect the muscles of the face, neck, and throat.
The exact cause of IBM is unknown, but it is believed to involve both genetic and environmental factors. An autoimmune disease, IBM occurs when the immune system mistakenly attacks the body's own tissues. A protein deposit called inclusion body is produced by the immune system that targets the muscle fibers in IBM. Inflammation, damage, and atrophy occur in the muscles as a result of these inclusion bodies, which interfere with their normal function and structure.
Some possible risk factors for developing IBM include:
Having a family history of IBM or other muscle diseases
Having certain genetic mutations or variations that affect the muscle proteins
Having exposure to certain viruses, toxins, or drugs that may trigger or worsen the immune response
Having aging-related changes in the muscle cells that may increase their vulnerability to damage
The symptoms of IBM usually develop gradually and worsen over time. Some common symptoms include:
Difficulty walking, climbing stairs, or rising from a chair
Frequent falls or tripping
Weakness and wasting of the muscles of the wrists, fingers, knees, ankles, and feet
Difficulty swallowing, chewing, or speaking
Drooping of the eyelids or facial muscles
Muscle pain, cramps, or stiffness
Fatigue or reduced exercise tolerance
Some people with IBM may also develop other problems, such as:
Breathing difficulties or sleep apnea
Aspiration pneumonia or choking
Weight loss or malnutrition
Skin ulcers or infections
Depression or anxiety
IBM can be difficult to diagnose, as it can mimic other muscle diseases or conditions. The diagnosis of IBM is usually based on a combination of:
Medical history and physical examination
Blood tests to check the levels of muscle enzymes, antibodies, and other markers
Electromyography (EMG) to measure the electrical activity of the muscles
Muscle biopsy to examine the tissue samples under a microscope
Magnetic resonance imaging (MRI) to obtain images of the muscles
There is no cure for IBM, and the treatment options are limited and mostly supportive. The main goals of treatment are to slow down the progression of the disease, relieve the symptoms, and improve the quality of life of the patient.
Some possible treatments for IBM include:
Medications to suppress the immune system, such as corticosteroids, methotrexate, or rituximab
Medications to reduce the inflammation, pain, or stiffness, such as nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, or gabapentin
Medications to improve the muscle strength or function, such as pyridostigmine, leucine, or creatine
Medications to treat the complications, such as antibiotics, antacids, or antidepressants
Physical therapy to maintain or improve the range of motion, flexibility, and balance of the muscles and joints
Occupational therapy to assist with the daily activities and provide adaptive devices or aids
Speech therapy to help with the swallowing and communication problems
Nutritional therapy to provide adequate calories, protein, and fluids to prevent weight loss or malnutrition
Respiratory therapy to monitor and support the breathing function and prevent infections
Surgery to correct the drooping of the eyelids or facial muscles
IBM cannot be prevented in most cases, as the cause is unknown or unavoidable. However, some possible ways to reduce the risk or severity of IBM include:
Avoiding smoking, alcohol, and drugs that may harm the muscles or the immune system
Taking medications and treatments as prescribed by the doctor for any underlying conditions that may affect the muscles or the immune system
Having regular check-ups and tests to monitor the muscle function and the overall health
Following the doctor’s advice and instructions regarding the exercise, diet, and lifestyle
Having regular follow-ups and evaluations to monitor the disease progression and the treatment outcomes
Inflammatory, weakness, and wasting of the skeletal muscles are symptoms of IBM. With proper diagnosis, treatment, and care, most patients can manage their symptoms and maintain their independence.
