What is Mitochondrial Disease?
Mitochondrial disease refers to a group of conditions affecting the mitochondria. A genetic mutation in the mitochondria causes mitochondrial disease. (MitoCanada)
The mitochondria is the structure in a cell responsible for producing energy. Healthy mitochondria will convert oxygen and the sugar, protein, and fat from food into energy. This energy is vital for organs such as the muscles, brain, liver, kidneys, digestive tract, and heart to function. In the cell, mitochondria that are dysfunctional due to mutation may produce less energy and can result in organs being dysfunctional. (Children's Hospital of Philadelphia; GARD; MitoCanada)
Currently, mitochondrial dysfunction is associated with over 300 disorders. Mitochondrial disease can present itself at birth but can also appear later in life. It is estimated that 1 in every 4,000 people has mitochondrial disease and that every 30 minutes, a baby is born with the condition. (MitoCanada; Mito Action)
Signs and Characteristics
Mitochondrial disease is a rare disease that is difficult to diagnose due to the different signs and characteristics present in each person. Even someone in the same family with the same mitochondrial disease may experience different signs and characteristics. The severity and the age that symptoms present themselves can be varied. (Cleveland Clinic; NORD)
To learn more about rare diseases, click here.
Mitochondrial disease signs and characteristics can affect various parts of the body such as the brain (neurological), eyes (ocular), gastrointestinal tract, cardiovascular system, the muscles (musculoskeletal), and other general areas. (Mito Action; Children's Hospital of Philadelphia)
It includes having difficulty paying attention, seizures, headaches, physical dysfunction, loss of control of body movements, muscles that contract jerky, and noise, light, and smell sensitivity. (Mito Action; Cleveland Clinic)
The degeneration of the retina can cause night blindness, a decrease in visual acuity, and colour vision deficits. The eyes' muscles may also become weak or paralyzed. Additional signs and characteristics may include the eyes not moving together, blurry vision or the upper eyelid can become droopy. (Mito Action; Cleveland Clinic)
Includes unexplained liver failure, impairment of the digestive tract muscles causing food to not move through the system properly, a lack of appetite or having difficulty eating, nausea, inability to swallow, or stomach cramps. (Mito Action; Cleveland Clinic)
The heartbeat may be irregular, or blood pressure may be a concern if it's too high or too low. If a child has an unexplained heart block, this can be one of the signs. Additionally, in the body, there may be a build-up of lactic acid. (Mito Action; Cleveland Clinic)
Someone with mitochondrial disease may experience pain in the muscles or, in general, the cramping of muscles, joint pain, or muscle weakness. Muscles may also not be as coordinated, or an individual may experience an inability to gain weight or grow at the expected rate. (Mito Action; Cleveland Clinic)
Other general areas
Individuals with mitochondrial disease may also experience a lack of energy, shortness of breath, sores on the mouth, fever, dizziness, congestion, coughing, dry skin, or an intolerance to exercise. Occasionally some may experience kidney stones or swollen hands. (Mito Action; Cleveland Clinic)
Who is at risk for Mitochondrial Disease?
Before discussing mitochondrial disease diagnosis, it is important to understand who is at risk for developing the disease. Mitochondrial disease is a genetic condition that is inherited from parents. In this case, the individual would have received a mutated gene from one or both parents. Genes provide the body with instructions for the creation of proteins that are crucial for the body to function correctly. When genes become mutated, protein products may become dysfunctional, absent, overproduced, or inefficient. These proteins are important for mitochondria health and for the mitochondria to perform and develop correctly. Proteins aid in the process of converting oxygen alongside sugar, protein, and fat from food into energy for the body. A lack of energy can lead to the signs and characteristics listed above. (NORD; GARD)
Mitochondrial disease affects all genders, all ages, and individuals from any ethnicity or race. Mitochondrial disease is a rare disease but is also one of the most common types of metabolic disease. Metabolic diseases are a group of conditions that occur at the same time and can result in metabolism problems (problems in the bodily reactions that occur in order to produce energy).(MayoClinic; NORD)
Receiving a diagnosis
Although an individual may experience some of the signs and characteristics listed above, the signs and characteristics aren't unique to mitochondrial disease. However, if an individual is experiencing three or more signs and characteristics, there is a possibility they may have mitochondrial disease, specifically if it involves multiple organ systems.
There is not one single test available to determine whether or not someone has mitochondrial disease. When seeing a health care practitioner, they will usually ask about medical history and family health history since mitochondrial diseases are genetic. Additionally, physical and neurological tests may also be done. The physical and neurological exams may include exercise tests for endurance and strength, or skill tests for reflexes, speech, thought, and vision. (MitoCanada; NIH)
Additional laboratory tests or screenings may take place to check organ function or to detect any abnormalities. Another possible test is routine urine or blood testing to identify elevated lactic acid levels since lactic acidosis (lactic build-up) is common in mitochondrial diseases. One important test that health care practitioners may use is a muscle biopsy. This test takes a small sample of muscle tissue from the body in order to examine the muscle cells for excessive mitochondria or an absence of mitochondrial enzymes. (NIH; NORD)
Finally, a genetic test can be conducted to confirm a diagnosis by determining if the genetic mutation that causes mitochondrial disease is present. Taking a blood test or doing a muscle biopsy can be used for genetic testing. A positive result may confirm a mitochondrial disease diagnosis, but a negative result is more difficult to interpret. If someone receives a negative test, it may mean that a person has the genetic mutation and can have mitochondrial disease, but that the test was not able to detect it. (NIH; NORD; GARD)
Speak to a health care provider about getting tested for Mitochondrial disease if you're at risk or have a family member with mitochondrial disease.
Currently, mitochondrial disease has no cure. However, treatments are available that help with the management of signs and characteristics and help slow the progression of mitochondrial disease. Treatment plans will differ for every individual and should be discussed with a health care practitioner. (NORD)
Vitamins and supplements
Sometimes referred to as the "Mito Cocktail," a mix of various vitamins and supplements have shown good responses in people living with mitochondrial disease. Vitamins and supplements are the most common mitochondrial treatment and usually include a combination of acetyl-L-carnitine, riboflavin (vitamin B2), thiamine (vitamin B1), coenzyme Q10, and creatine monohydrate. The vitamins and supplements listed are not an exhaustive list. A health care specialist will create a specific mix to match each case. This mix of vitamins is meant to help replace deficiencies that occur due to the mitochondrial energy production not functioning properly. (NORD; MitoCanada; Cleveland Clinic)
Exercise is proven to be one of the most beneficial treatments for mitochondrial disease. Exercise can include a variety of activities, such as swimming, walking, cycling, weight lifting, and much more. Exercising increases the amount of energy produced in the body, which improves the function of mitochondria and increases the number of healthy mitochondria in cells. As individuals exercise, the body learns to use oxygen more efficiently, resulting in a build-up of exercise tolerance over time. There has been research that supports the idea that if exercise is increased slowly, it can be safe for those with mitochondrial diseases. This is important since, for mitochondrial disease, exercise intolerance is common. A physician will help to incorporate an exercise plan based on the individual into a treatment plan. (MitoCanada; Mito Action; Cleveland Clinic)
Other treatments exist for each sign and characteristic present, such as anti-seizure medications for seizures, cochlear implants for hearing loss, or eye crutches for drooping eyelids. Certain therapies such as speech therapy, respiratory therapy, or physical therapy may also be included in treatment. Based on the signs and characteristics present, a health care practitioner will recommend the best course of treatment. (NORD; Cleveland Clinic)
Living with Mitochondrial Disease
Mitochondrial disease can cause various signs and characteristics to be present that impact an individual's life quality. Receiving a diagnosis and living with mitochondrial disease can be a challenge that often causes mental and physical health to become worn down. However, there are things that can improve the quality of life for individuals living with mitochondrial disease.
- Having a secure network of family and friends who act as a support system can be key for improving quality of life. Having people who show encouragement and support when you need it has been shown to improve mental health. This can help ease the stress and anxiety that is associated with a diagnosis. (National Institute of Mental Health)
- Mitochondrial disease can cause individuals to feel higher levels of fatigue and exercise intolerance. Following an exercise plan set in place by a physician can help lower exercise intolerance and improve fatigue over time. Exercise intensity and duration should be slowly increased as per a physician's instructions to avoid overworking the body. Exercise can help to stimulate mental health. (Verhaak et al.)
- When being diagnosed with a medical condition, it can be common to feel stressed and anxious. It can cause feelings of isolation, uncertainty about the future, financial strain, and discomfort in signs and characteristics. One way to obtain stress relief can be by having open communication with both a care team and loved ones about how you're feeling. Other ways to obtain stress relief include exercise, socializing, or meditation. (Fabry Disease News; Healthline)
- Take advantage of the community resources available to individuals who are living with a medical condition. There are government services and resources available to make life easier and to help in daily life, including therapy programs. (National Institute of Mental Health)
- As awareness gets raised for mitochondrial disease, more options may become available. It may be useful to stay up to date on mitochondrial news and clinical trials that are happening. (Mito Action)