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Mitochondrial Myopathies


Michael Rubin

, MDCM, New York Presbyterian Hospital-Cornell Medical Center

Last full review/revision Jul 2020| Content last modified Jul 2020
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Mitochondrial myopathies are muscle disorders inherited through faulty genes in the mitochondria or in the nuclear genes that control mitochondrial function. The muscles and organs such as the brain, nerves, and retinas are affected.

Mitochondria are the energy factories of cells and carry some of their own genes. When mitochondria stop working properly, less and less energy is generated within the cells. This may lead to cell injury or even cell death, and body systems, often including the muscles, will not function properly. Mitochondrial myopathies can be inherited through faulty genes within the mitochondria themselves or through genes within the cell nucleus.

Mitochondrial myopathies can cause increasing weakness in one or a few muscle groups, such as the eye muscles (ophthalmoplegia) and often affect many other organs, such as the heart, intestines, or brain. Infants whose muscles are affected are weak and have severely reduced muscle tone (hypotonia, or "floppiness"). Depending on which organs are affected, complications may include deafness or hearing loss, seizures, or stroke-like episodes. One mitochondrial myopathy is called Kearns-Sayre syndrome. It causes problems with the eyes, muscles, and heart.

Treatment of Mitochondrial Myopathies

No specific treatment is available for mitochondrial myopathy, but various drugs and treatments are used to manage symptoms and complications.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

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