Mitochondria are tiny structures in all cells. They provide energy. Mitochondrial myopathies are a group of diseases that affect them. The diseases affect the nerves and muscles, among other systems. The severity of these diseases can vary greatly. Some produce mild symptoms and others have life-threatening conditions. Mitochondrial myopathies include:
NAME OF CONDITION
AGE OF ONSET
Kearns-Sayre Syndrome (KSS)
Before age 20
Salt and pepper pigmentation in eye, eye movement problems (PEO), heart and skeletal muscle dysfunction
Brain abnormalities that lead to muscle problems, seizures, uncoordinated muscle movement (ataxia), impaired vision and hearing, developmental delay and poor control over breathing
Mitochondrial DNA Depletion Syndrome
Muscle weakness and liver failure, floppiness, feeding difficulties, and developmental delay
Mitochondrial Encephalomyopathy, Lactic Acidosis and Strokelike Episodes (MELAS)
Childhood to adulthood
Strokelike episodes, migraine headaches, vomiting and seizures, muscle weakness, exercise intolerance, hearing loss, diabetes, short stature
Myoclonic Epilepsy associated with Ragged Red Fibers (MERRF)
Late childhood to adulthood
Myoclonus (jerky movements), seizures, muscle weakness, uncoordinated muscle movement (ataxia)
This condition is caused by mutation in the genes.
Having a family member with the gene.
Mitochondrial myopathies can cause a range of symptoms. Some people experience very few symptoms. Others may experience the full range. If you have any of these symptoms, do not assume it is due to this condition, as these symptoms may be caused by a number of conditions.
Fauci AS, Braunwald E, Kasper DL, Hauser SL, Longo DL, Jameson JL, and Loscalzo J, Eds.
Harrison's Principles of Internal Medicine
. 17th edition. United States:The McGraw-Hill Companies; 2008:Chapter 382, Muscular Dystrophies and Other Muscle Diseases.
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provided by your physician. It is neither intended nor implied to be a
substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER
IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the
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