Thursday, March 3, 2016

Dysphagia Evaluation and Treatment Info for Myositis

Here's another awesome project by my student Ani Haas! 

If you have a patient with Myositis, this info is a great guide for dysphagia therapy with these patients.  Are exercises appropriate?  What is the prognosis?  What compensatory strategies tend to be helpful?  Other considerations.  Let us know in the comments if you found this helpful! 



Myositis

Background:
Myositis is a general term meaning inflammation of the muscles. Inflammatory myopathies are the largest group of potentially treatable myopathies in children and adults.  The disorders are best classified on the basis of distinct clincopathologic features.  To date, there are four subtypes: dermatomyositis, polymyositis, necrotizing autoimmune myositis, and inclusion-body myositis. Correct subtype identification and the distinction of these conditions from other diseases that have similar characteristics are fundamental in differing prognosis and differing responses to therapy.

Symptoms:

People with inflammatory myopathies have increasing difficulty with tasks that require the use of proximal muscles. An example of this is getting up from a chair, climbing stairs, or lifting objects.  People may feel tired after standing or walking, have muscle pain or soreness that lasts for weeks, and may have trouble holding their head up. With certain subtypes, some patients may experience difficulty swallowing, cardiac arrhythmia, ventricular dysfunction, or fever.

Specific Clinical Features:

Dermatomyositis: Affects both children and adults. Early symptoms include skin manifestations, a blue-purple rash with edema accompanying or proceeding muscle weakness. Muscle strength may not be affected and the dermatomyositis may be limited to the skin.

Polymyositis: This subtype is rare, often mis-diagnosed, and will stand-alone.  Proper diagnosis is based on exclusion and is often diagnosed as sub acute proximal myopathy in adults who do not have a rash, family history of neuromuscular disease, exposure to mytoxic drugs like statins, penicillamine, or any facial or extraocular muscle involvement.

Necrotizing Autoimmune Myositis: This subtype makes up almost 20% of all myopathies.  It can occur at any age but is typically seen in adults.  It can occur alone or following a viral infection.  It causes severe weakness and very high creatine kinase levels in the blood.

Inclusion-Body Myositis: Inclusion-Body Myositis (IBM) is the most common and disabling inflammatory myopathy among people 50 years of age or older.  It is thought to be an insidious disease that develops over a period of years.  It often simulates a late-life muscular dystrophy or slowly progressive motor-neuron disease. Early clinical features of IBM include involvement of distal muscles, especially foot extensors and finger flexors, atrophy of the forearms and quadriceps muscles.



Causes:
Myositis can be caused by anything that leads to inflammation of the muscles. Common causes include; inflammatory conditions, viral infections, drugs, injury, or Rhabdomyolysis (a breakdown of muscle tissue that releases a damaging protein into the blood).

Diagnosis of Myositis:
Blood tests: Testing for elevated levels of muscle enzymes, like creatine kinase, which will be present in patients with active disease.
MRI: A MRI is helpful for diagnosis when muscle edema is present, identifying which particular muscles are affected by atrophy.
EMG: By inserting needle electrodes into muscles, a doctor can test the response of muscles to electrical nerve signals. EMG can identify muscles that are weak or damaged by myositis. EMG can also be used to rule out neurogenic conditions and assess disease activity.
Muscle biopsy: This is the most accurate test for diagnosing myositis. A doctor identifies a weak muscle, makes a small incision, and removes a small sample of muscle tissue for testing. Muscle biopsy leads to a final diagnosis in most people with myositis.

Treatment Options:
Currently, there are differing treatment options for specific subtypes:

Treatment of dermatomyositis, polymyositis, and necrotizing autoimmune myositis:
 Once daily doses of oral prednisone, a corticosteroid, is the first-line drug in combating the above inflammatory myopathies. Corticosteroids slow the body's immune system and stop the inflammatory attack on muscle, skin and other body systems. These medicines control the inflammation, ease pain, and increase muscle strength.

Immunosuppressant: Commonly used is methotrexate and azathioprine is often used in combination with prednisone. They may help the patient to taper off prednisone more quickly and avoid some of the unwanted effects.

Intravenous immune globulin (IVIG): IVIG is a blood product derived from human plasma. IVIG is used to boost the body's immune system response, IVIG is usually reserved for cases resistant to other treatments.

Treatment of Inclusion-Body Myositis (IBM):
Due to the slow and progressive course of IBM, the degenerative effects are already advanced by the time the patient seeks medical help. Musculature of the pharynx is at risk for inflammatory myopathic changes, which can cause dysphagia.  Treatment options used to treat other myositis diagnosis have been ineffective in treating IBM; there is no clear treatment option for IBM. Treatment is aimed at delaying the progression of the disease.



Dysphagia in Myositis:
Due to ineffective drug treatment options for IBM, dysphagia is more common in IBM than any other inflammatory myopathy. Dysphagia in patients with IBM contributes to aspiration pneumonia associated respiratory failure, which is the most common cause of death in people with IBM.

Clinical Features of Dysphagia in IBM:
Patients may experience feeling of:
1. Food sticking in throat
2. Coughing during meals
3. Nasal reflux
4. Difficulty with dry foods, solids, and thin liquids most frequently.

Clinical oral exam on patients with IBM typically show normal lingual range of motion, strength, and coordination.  Some patients may exhibit reduced laryngeal elevation

Videofluroscopic abnormalities in patients with IBM included:  
1. Residual pharyngeal pooling  
2. Reduced pharyngeal constrictor contraction
3. Impaired laryngeal elevation
4. Cricopharyngeal (CP) dysfunction noted by poor relaxation and narrowing of upper esophagus
5. Tongue base weakness
6. Reduced laryngeal elevation.
7. Zenker’s Diverticulum

Phases of Swallowing Effected:

Oral Phase: The oral phase of the swallow may be marked by slow bolus delivery due to slowed limb movements. Patients may also exhibit slowed mastication. Patients are at risk for malnutrition because feeding is difficult and lengthy and patients may lose motivation to finish meals.

Pharyngeal Phase: The pharyngeal phase of swallowing is potentially the most affected by IBM. This is because this phase in swallowing relies on skeletal muscles that may be affected by myopathic changes. The upper esophageal sphincter (UES), which allows food to pass into the esophagus may be unable to relax, causing dysphagia.

Swallowing Rehabilitation:
Patients should receive clinical dysphagia evaluations along with videofluoroscopy.  Swallowing rehabilitation can include: diet modifications, feeding strategies, compensatory techniques, and exercises. A combination of oral and enteral feeding may be necessary for some patients. Extreme cases may require exclusive enteral nutrition.


Feeding Strategies:
Feeding strategies include:
1.      Chewing food well
2.      Double swallow
3.      Small bites
4.      Alternating solids and liquids
5.      Upright position during feeding

Compensatory Techniques:
Compensatory techniques include:
1.      Chin tuck
2.      Head turn, trial both sides
3.      Effortful swallow
4.      Mendelsohn maneuver
5.      Supraglottic swallow

Swallow Exercises:
Swallow exercise should be based off of swallow dysfunction noted during videofluoroscopy. Typical exercises implemented include:
1.      Masako (tongue hold)
2.      Mendelsohn maneuver
3.      Falsetto
4.      Supraglottic exercises

Interventional Measures:
Swallow rehabilitation including the above mentioned strategies might not be sufficient in treating some patients with IBM.  Interventional measures include:
1.      Cricopharyngeal myotomy
2.      Pharyngoesophageal dilation
3.      Botulinum injections
4.      Percutaneous endoscopic gastrostomy

Of these interventional measures, cricopharyngeal myotomy is the most well documented surgical technique for alleviating cricopharyngeal spasm or uncoordinated pharyngeal contraction.  The best results are when a long myotomy (6 cm or greater) is created.  This is because it incorporates the cricopharyngeus that extends into the constrictor above and the esophageal musculature below, which is aimed at improving pressure generation and cricopharyngeal opening.

Dysphagia is a progressive condition in patients with IBM.  It often leads to death from aspiration pneumonia. Immunosuppressive therapy has shown not to be beneficial when treating patients with IBM. Treatment of CP dysfunction seems to provide some symptomatic benefit.  Unfortunately, due to the progressive nature of the disease, pharyngeal function seems to worsen and enteral feeding may become the patient’s only option. Until then, feeding strategies, compensatory techniques, swallow exercises, and interventional measures can help in treating dysphagia in patients with IBM.  


References

Dalakas, M. C., Sonies, B., Dambrosia, J., Sekul, E., Cupler, E., & Sivakumar, K. (1997). Treatment of inclusion-body myositis with IVIg: A double-blind, placebo-controlled study. Neurology, 48(3), 712-716.

Dalakas, M. C. (2015). Inflammatory Muscle Disease. Inflammatory Muscle Disease, 372(18).

Houser, S. M., Calabrese, L. H., & Strome, M. (1998). Dysphagia in patients with inclusion body myositis. Laryngoscope The Laryngoscope, 108(7), 1001-1005.

Oh, T. H., Brumfield, K. A., Hoskin, T. L., Kasperbauer, J. L., & Basford, J. R. (2008). Dysphagia in Inclusion Body Myositis: Clinical Features, Management, and Clinical Outcome. American Journal of Physical Medicine & Rehabilitation, 87(11), 883-889. Retrieved February 14, 2016.

Pars, K., Garde, N., Skripuletz, T., Pul, R., Dengler, R., & Stangel, M. (2013). Subcutaneous immunoglobulin treatment of inclusion-body myositis stabilizes dysphagia. Muscle & Nerve Muscle Nerve, 48(5), 838-839.

TMA - The Myositis Association. (n.d.). Retrieved February 28, 2016, from http://www.myositis.org/

Wintzen, A. R., Ambots, G. T., De Bakker, H., Hulshof, J. H., & Padberg, G. W. (1988). Dysphagia in inclusion body myositis: Clinical Features, Management, and Clinical Outcome. Journal of Neurology, 51, 1542-1545.