Neuromuscular disease
Neuromuscular disease is a broad term that encompasses many diseases and ailments that impair the functioning of the muscles, either directly, being pathologies of the voluntary muscle, or indirectly, being pathologies of nerves or neuromuscular junctions.[2][4]
Neuromuscular disease | |
---|---|
Congenital nemaline myopathy (neuromuscular disorder) | |
Specialty | Neurology, physical medicine and rehabilitation |
Causes | Autoimmune disorders[1], genetic disorders[2], environmental factors[3] |
Diagnostic method | Muscle electrophysiology tests, genetic testing |
Treatment | Depends on the disorder; many currently have no cure[2] |
Neuromuscular diseases are those that affect the muscles and their direct nervous system control; problems with central nervous control can cause either spasticity or some degree of paralysis (from both lower and upper motor neuron disorders), depending on the location and the nature of the problem. Some examples of central disorders include cerebrovascular accident, Parkinson's disease, multiple sclerosis, Huntington's disease and Creutzfeldt–Jakob disease. Spinal muscular atrophies are disorders of lower motor neuron while amyotrophic lateral sclerosis is a mixed upper and lower motor neuron condition.
Symptoms and signs
Symptoms of neuromuscular disease may include the following:[2][5]
- Numbness
- Paresthesia
- Muscle weakness
- Muscle atrophy
- Myalgia (muscle pain)
- Fasciculations (muscle twitches)
Causes
Neuromuscular disease can be caused by autoimmune disorders,[1] genetic/hereditary disorders[2] and some forms of the collagen disorder Ehlers–Danlos Syndrome,[6] exposure to environmental chemicals and poisoning which includes heavy metal poisoning.[3] The failure of the electrical insulation surrounding nerves, the myelin, is seen in certain deficiency diseases, such as the failure of the body's system for absorbing vitamin B-12[3]
Diseases of the motor end plate include myasthenia gravis, a form of muscle weakness due to antibodies against acetylcholine receptor,[7] and its related condition Lambert-Eaton myasthenic syndrome (LEMS).[8] Tetanus and botulism are bacterial infections in which bacterial toxins cause increased or decreased muscle tone, respectively.[9] Muscular dystrophies, including Duchenne's and Becker's, are a large group of diseases, many of them hereditary or resulting from genetic mutations, where the muscle integrity is disrupted, they lead to progressive loss of strength and decreased life span.[10]
Further causes of neuromuscular diseases are :
Inflammatory muscle disorders
- Polymyalgia rheumatica (or "muscle rheumatism") is an inflammatory condition that mainly occurs in the elderly; it is associated with giant-cell arteritis(It often responds to prednisolone).[11]
- Polymyositis is an autoimmune condition in which the muscle is affected.[12]
- Rhabdomyolysis is the breakdown of muscular tissue due to any cause.[13]
Tumors
- Smooth muscle: leiomyoma (benign)[14]
- Striated muscle: rhabdomyoma (benign)[15]
Diagnosis
Diagnostic procedures that may reveal muscular disorders include direct clinical observations. This usually starts with the observation of bulk, possible atrophy or loss of muscle tone. Neuromuscular disease can also be diagnosed by testing the levels of various chemicals and antigens in the blood, and using electrodiagnostic medicine tests[16] including electromyography[17] (measuring electrical activity in muscles) and nerve conduction studies.[18]
In neuromuscular disease evaluation, it is important to perform musculoskeletal and neurologic examinations. Genetic testing is an important part of diagnosing inherited neuromuscular conditions.[16]
Prognosis
Prognosis and management vary by disease.
See also
References
- Kraker, Jessica; a. Zivkovic, Sasa (2011). "Autoimmune Neuromuscular Disorders". Current Neuropharmacology. 9 (3): 400–8. doi:10.2174/157015911796558000. PMC 3151594. PMID 22379454.
- "Neuromuscular Disorders: MedlinePlus". www.nlm.nih.gov. Retrieved 2016-04-24.
- Swash, Michael; Schwartz, Martin S. (2013-03-14). Neuromuscular Diseases: A Practical Approach to Diagnosis and Management. Springer Science & Business Media. p. 86,196. ISBN 9781447138341.
- Hill, M (2003). "The Neuromuscular Junction Disorders". Journal of Neurology, Neurosurgery & Psychiatry. 74 (90002): ii32–ii37. doi:10.1136/jnnp.74.suppl_2.ii32. PMC 1765619. PMID 12754327.
- "Myopathy Information Page: National Institute of Neurological Disorders and Stroke (NINDS)". www.ninds.nih.gov. Retrieved 2016-04-24.
- Voermans, Nicol C; Van Alfen, Nens; Pillen, Sigrid; Lammens, Martin; Schalkwijk, Joost; Zwarts, Machiel J; Van Rooij, Iris A; Hamel, Ben C. J; Van Engelen, Baziel G (2009). "Neuromuscular involvement in various types of Ehlers-Danlos syndrome". Annals of Neurology. 65 (6): 687–97. doi:10.1002/ana.21643. PMID 19557868.
- Myasthenia Gravis at eMedicine
- Lambert-Eaton Myasthenic Syndrome (LEMS) at eMedicine
- Kumar, Vinay; Abbas, Abul K.; Aster, Jon C. (2014-09-05). Robbins & Cotran Pathologic Basis of Disease. Elsevier Health Sciences. p. 382. ISBN 9780323296359.
- "Muscular Dystrophy Information Page: National Institute of Neurological Disorders and Stroke (NINDS)". www.ninds.nih.gov. Retrieved 2016-04-24.
- Liaison, Janet Austin, Office of Communications and Public. "Polymyalgia Rheumatica and Giant Cell Arteritis". www.niams.nih.gov. Retrieved 2016-04-24.
- Polymyositis at eMedicine
- MedlinePlus Encyclopedia Rhabdomyolysis
- Leiomyoma at eMedicine
- Rhabdomyomas at eMedicine
- McDonald, Craig M (2012). "Clinical Approach to the Diagnostic Evaluation of Hereditary and Acquired Neuromuscular Diseases". Physical Medicine and Rehabilitation Clinics of North America. 23 (3): 495–563. doi:10.1016/j.pmr.2012.06.011. PMC 3482409. PMID 22938875.
- Darras, Basil T.; Jr, H. Royden Jones, Jr; Ryan, Monique M.; Vivo, Darryl C. De (2014-12-03). Neuromuscular Disorders of Infancy, Childhood, and Adolescence: A Clinician's Approach. Elsevier. p. 488. ISBN 978-0124171275.
- Electromyography and Nerve Conduction Studies at eMedicine
Further reading
- Wokke, John H. J.; Doorn, Pieter A. van; Hoogendijk, Jessica E.; Visser, Marianne de (2013-03-07). Neuromuscular Disease: A Case-Based Approach. Cambridge University Press. ISBN 9781107328044.
- Ambrosino, N; Carpene, N; Gherardi, M (2009). "Chronic respiratory care for neuromuscular diseases in adults". European Respiratory Journal. 34 (2): 444–451. doi:10.1183/09031936.00182208. PMID 19648521.