Kearns-Sayre syndrome (KSS) is a rare neuromuscular condition that impacts your eyes and other parts of your body, including your heart. It happens due to a defect in the DNA of mitochondria, which help produce most of your body’s energy. Most people with KSS develop symptoms before age 20. There isn’t a cure, but treatment options can help.
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Kearns-Sayre syndrome (KSS) is a rare neuromuscular condition. It impacts your eyes and other parts of your body, including your heart. Most people with KSS develop symptoms before age 20.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
Kearns-Sayre Syndrome is a rare mitochondrial disease that doesn’t have a cure. It’s named for Thomas P. Kearns and George Pomeroy Sayre, who first described the disease in 1958. It worsens over time (progressive), leading to a range of health issues that often involve your eyes, heart, muscles and cognition (ability to think and reason). Early diagnosis and ongoing treatment can help you or your child manage symptoms for an improved quality of life.
Mitochondria are tiny rod-like structures that exist in every cell of your body, except red blood cells. Mitochondria are the “energy factories” of your body. They produce 90% of the energy needed to support body function and growth. Mitochondria use oxygen to convert fuel from the food you eat into energy your cells can use.
When mitochondria are abnormal or damaged, they begin to fail. Your body doesn’t get enough energy to work properly.
Mitochondrial diseases are difficult to diagnose and treat because they affect multiple body systems (cells, tissues and organs). While symptoms of mitochondrial disease can vary in severity, they typically worsen over time. They often damage muscles and nerve cells, which depend on a lot of energy to work as they should.
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Kearns-Sayre syndrome can affect both men and women. Usually, the genetic changes that cause KSS happen as a baby develops during pregnancy. These genetic changes (mutations) occur in their mitochondria.
This genetic disorder can be passed down from mothers (maternal inheritance), but may also occur without a family history. Genetic testing may help to determine if the mutation was inherited (passed down) or not.
Many conditions have symptoms that resemble Kearns-Sayre syndrome, affecting your eyes, muscles and other parts of your body. They include, but aren’t limited to:
Getting an accurate diagnosis is important, so you or your child can receive appropriate care for KSS.
Other names for Kearns-Sayre syndrome are:
Kearns-Sayre syndrome is rare. An estimated 1 to 3 people out of every 100,000 have the disease.
KSS happens due to a genetic mutation in mitochondrial DNA (mtDNA). This type of DNA affects genes needed for healthy mitochondrial function. Researchers don’t know why the genetic change happens.
Signs of Kearns-Sayre syndrome usually occur before age 20 and first affect your eyes. Over time, the disease may cause blindness. Early symptoms include:
KSS also causes a range of other symptoms, including
It can be challenging to diagnose Kearns-Sayre syndrome. It can involve many body systems. You may notice unusual symptoms in yourself or your child. Or a healthcare provider may notice symptoms during a checkup. If you observe any signs or symptoms, see your healthcare provider.
To diagnose KSS, healthcare providers:
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Your healthcare provider may also take a biopsy of your muscle tissue to look for ragged-red fibers. These indicate abnormal muscle cells due to mitochondrial disease. Imaging studies to rule out other conditions may include:
Early detection is essential for effective treatment. Getting the proper diagnosis ensures that you, or your child, receive appropriate care.
There isn’t a cure for Kearns-Sayre syndrome. Early detection and supportive care can help reduce the risk of complications. Your healthcare provider can recommend therapies to help you or your child manage symptoms so you can live a better quality of life.
Kearns-Sayre syndrome requires a range of expertise, as it can affect many parts of your body. Your care team may include:
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Treatment focuses on managing symptoms and reducing complications as the condition progresses.
Physical and occupational therapy can help with coordination, strength and balance problems. Your healthcare provider may also prescribe medication to treat heart or hormone conditions or psychological symptoms such as depression.
Your healthcare provider may recommend:
Ongoing monitoring is necessary if you or your child has KSS. New symptoms often arise as organ systems fail over time. Talk to your healthcare provider about options to help you live longer and better.
There isn’t a way to prevent Kearns-Sayre syndrome, and nothing you do causes it. It happens due to genetic mutations as a baby develops in the womb.
The outlook for Kearns-Sayre syndrome depends on symptoms and their severity. Most people with the condition live for several decades. Supportive treatment options can provide you or your child a longer, healthier life.
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Early detection of Kearns-Sayre syndrome is important to manage symptoms and reduce the risk of complications. Genetic testing can confirm a diagnosis so you receive the appropriate care. Your healthcare provider works with you to customize a care plan that meets your needs and goals.
A note from Cleveland Clinic
Kearns-Sayre syndrome is a challenging disease to diagnose and treat, as it can affect so many parts of your body. Pay attention to how you feel as new symptoms arise. And check in with your healthcare provider regularly. Working together, you can find ways to address problems promptly so you stay as healthy as possible, for as long as possible.
Last reviewed on 05/19/2022.
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