What is Mitochondrial disease and what causes it?
Mitochondria are the “powerhouse” of the cells that produce 90% of the energy needed to sustain life. In mitochondrial disorders, the mitochondria’s ability to convert food and oxygen into energy is impaired because of a genetic mutation in the DNA. We all have two types of DNA in our bodies. Nuclear DNA is found in the cell’s nucleus and is inherited from both our mother and father. Mitochondria also have DNA, inherited from mothers. Because both types of DNA are responsible for the structure and function of the mitochondria, mutations in either can cause mitochondrial disorders. Mutations can be inherited from parents or can occur randomly in a child called de novo mutations.
What are the symptoms?
The parts of the body that tend to be most affected are those that need the most energy such as the heart, brain, muscles and gastrointestinal tract. Symptoms can range from fatigue and exercise intolerance to poor growth, muscle weakness, developmental delays, vision and/or hearing loss, stroke, seizures, heart failure, diabetes and kidney failure. Symptoms may appear at birth or they may not appear until adulthood. Mitochondrial disease may progress quickly and can be severe or it can be stable and well-managed for years. There are no cures for mitochondrial diseases, but treatment can help reduce symptoms or slow the decline in health.
How is it diagnosed?
Because mitochondrial diseases affect so many different organs and patients present with many different symptoms, mitochondrial disease can be difficult to diagnose. No reliable and consistent means of diagnosis currently exists. This is why referral to a medical facility with physicians who specialize in these diseases is critical to making the diagnosis.