Monomelic amyotrophy
You don't need to be Editor-In-Chief to add or edit content to WikiDoc. You can begin to add to or edit text on this WikiDoc page by clicking on the edit button at the top of this page. Next enter or edit the information that you would like to appear here. Once you are done editing, scroll down and click the Save page button at the bottom of the page.
| Monomelic amyotrophy Classification and external resources |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Phone:617-632-7753
Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [2] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.
Monomelic amyotrophy (also known as MMA, Hirayama's disease, Sobue disease or Juvenile nonprogressive amyotrophy) is an untreatable, focal, lower motor neuron disease that primarily affects young (15 - 25 year-old) males in India and Japan. MMA is marked by insidious onset of muscular atrophy, which stabilizes at a plateau after two to five years from which it neither improves nor worsens. There is no pain or sensory loss associated with MMA. Unlike other lower motor neuron diseases, MMA is not believed to be hereditary and fasciculations (involuntary muscle twitches) are rare.
EMG tests reveal loss of the nerve supply, or denervation, in the affected limb without conduction block (nerve blockage restricted to a small segment of the nerve). Increased sweating, coldness and cyanosis have been reported for a few patients, indicating involvement of the sympathetic nervous system.
While MMA will cause weakness and/or wasting in only one limb, EMG and NCV tests often show signs of reinnervation in the unaffected limbs.
Treatment
There is no cure for MMA. Treatment consists of muscle strengthening exercises and training in hand coordination.
Prognosis
The symptoms of MMA usually progress slowly for one to two years before reaching a plateau, and then remain stable for many years. Disability is generally slight. Rarely, the weakness progresses to the opposite limb. There is also a slowly progressive variant of MMA known as O'Sullivan-McLeod syndrome, which only affects the small muscles of the hand and forearm and has a slowly progressive course.
Epidemiology
MMA occurs in males between the ages of 15 and 25. Onset and progression are slow. MMA is seen most frequently in Asia, particularly in Japan and India; it is much less common in North America.
External links
- monomelic_amyotrophy at NINDS
- MND Association
- Overview at Washington University
- Gourie-Devi M, Nalini A (2001). "Sympathetic skin response in monomelic amyotrophy". Acta Neurol. Scand. 104 (3): 162-6. PMID 11551236.
Acknowledgement and Attribution Regarding Sources of Content
Some of the initial content on this page may be incorporated in part from copyleft sources in the public domain including wikis such as Wikipedia and AskDrWiki. Drug information for patients came from the The National Library of Medicine. Infectious disease information may have come from the Centers for Disease Control (CDC). Differential Diagnoses are drawn from clinicians as well as an amalgamation of 3 sources: 1.The Disease Database; 2. Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:3; 3. Sailer, Christian, Wasner, Susanne. Differential Diagnosis Pocket. Hermosa Beach, CA: Borm Bruckmeir Publishing LLC, 2002:7 .
