Discussion
Mitochondrial myopathies are disorders characterized by morphological abnormalities of muscle mitochondria. Accumulating evidence suggests that mitochondrial disorders are among the most common inherited metabolic diseases. Similar to fibromyalgia, patients may present with muscle weakness, pain, fatigue and exercise intolerance that progressively worsens over time.
Several steps are involved in Adenosine-5'-triphosphate (ATP) generation in the mitochondria, and defects in any part of the cycle may impair energy production leading to symptoms. These abnormalities in generation and utilization of ATP can be assessed by specific tests, which as in our patient pointed towards problems in energy metabolism. Genetic testing with sequencing of the mitochondrial genome and chromosomal genes affecting mitochondrial function may also be pursued, as was performed in our patient. Mutations in POLG1 and several mitochondrial genome polymorphisms were noted.
Subsequently, our patient was started on a regimen of coenzyme Q10 (Co-Q10; ubiquinone), creatine, carnitine, folic acid and α-lipoic acid. Co-Q10 transports electrons between complex I and complex III of the mitochondrial respiratory chain and has been shown to improve mitochondrial function in several studies. Creatine generates additional ATP through the creatine phosphate shuttle. Carnitine enhances transport of fatty acids into the mitochondria. Folic acid is a cofactor for several mitochondrial enzymes, while α-lipoic acid is a strong antioxidant. Although this treatment regimen was started several years after symptom onset, within the first few months our patient showed tremendous improvement. With continued therapy, her complaints dissipated over several months, with a gradual but sustained resolution of all symptoms.