Mitochondrial Disease Symptoms

Mitochondria are the rod-shaped structures, present in every cell in the body. Mitochondria are protected by the outer and the inner membranes. They contain several enzymes and protein which are required for processing of carbohydrates and fats. Thus they help produce energy and hence are commonly known as 'powerhouse of the cells'.

Functions of Mitochondria

As explained above, mitochondria help release energy from the food we eat. The ATP (Adenosine Triphosphate) molecules produced in the mitochondria by the process of oxidative phosphorylation store this energy. Mitochondria also promote programmed cell death (apoptosis or prompt destruction of unwanted cells). Mitochondria are involved in synthesis of steroids, formation of important blood ingredients and hormones like estrogen and testosterone. They determine the growth and development of cells in various ways.

Mitochondrial Diseases

Certain reactions taking place in mitochondria can lead to excessive production of free radicals which in turn can damage mitochondria. Mitochondrial malfunction can result in abnormal cell death giving rise to a number of medical conditions. Though mitochondria are present in every cell of the body, they are present in large numbers in the muscle cells that need more energy. Since mitochondria play an important role in body metabolism, damage to mitochondria is exhibited through various symptoms. Diseases caused due to damage to mitochondria are referred to as mitochondrial myopathies which consist of a number of neuromuscular diseases like Kearns-Sayre syndrome, myoclonus epilepsy with ragged-red fibers, and mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes.

Symptoms of Mitochondrial Disease in Children and Adults

Infants may suffer from Mitochondrial DNA Depletion Syndrome (MDS). Symptoms like brain abnormalities, delay in reaching developmental milestones, difficulties with feeding, liver dysfunction, muscle weakness, etc. are noticed in infants with MDS.

Mitochondrial Encephalomyopathy with Lactic Acidosis and Stroke-like episodes (MELAS) is seen in children as well as adults. The symptoms are episodes of strokes, migraines, diabetes, hearing loss, and muscle fatigue. Muscle fatigue is one of the most common mitochondrial disease symptoms in adults. The symptoms seen in infants, usually become prominent before the age of 20.

Deafness, blindness, droopy eyelids, limited movement of the limbs or even eyes, nausea, vomiting, seizures, exercise intolerance, heart failure (the capacity of the heart to pump blood is severely affected), breathlessness are the common symptoms of mitochondrial diseases. Learning disabilities, gastrointestinal disorders, stunted growth, cataracts, loss of vision, loss of coordination are also common in patients of mitochondrial diseases. Muscle deterioration may lead to difficulties in speaking and swallowing. Pearson syndrome in infants exhibits symptoms like anemia and pancreas dysfunction.

Various tests help diagnose mitochondrial diseases. Doctors can confirm the diagnosis after examining the mitochondrial disease symptoms and test results. Unfortunately, there doesn't exist any specific treatment for mitochondrial diseases. Certain medications, physical therapy can help manage the symptoms. Vitamin therapies help improve the energy levels.

About one in 3-4 thousand people in the U.S. suffers from mitochondrial disease. The treatment may vary according to the type of the mitochondrial disease and severity of the symptoms. The prognosis for patients with mitochondrial diseases is greatly influenced by the type of disease and the degree of involvement of various organs. Since these diseases are responsible for progressive weakness, they can eventually lead to death.