February 26, 2001
Physicians, Researchers & Families Battle
Devastating Mitochondrial Disease
International Conference Scheduled for Feb. 28-March 4 in San Diego
Physicians and the public are only now beginning to learn about the devastation and death that results from defective mitochondria, thread-like structures inside cells that function as power generators converting the potential energy provided by food into energy that can be used by the body.
Tall, Skinny and Very Sick
While he was growing up, Mark Clayton was a tall, skinny kid who was never quite as fast or strong as the other children. Today, at age 45, the San Diegan is 6 feet 5 inches and only 145 pounds. About 10 years ago, Mark’s general weakness got worse; he began to fall and he had trouble getting up from chairs. After an EMG and muscle biopsy last year, Mark got the diagnosis of mitochondrial disease. A mechanical designer, he is able to continue in his profession, but he has considerable trouble walking. He knows there is no cure to this progressive disease.
Mitochondria are responsible for creating more than 90 percent of the energy needed by the body to sustain life and growth. In addition, the mitochondria are essential for metabolic functions that help each tissue to perform its role in the day-to-day operation of the body. When mitochondria fail, less and less energy is generated within the cell, resulting in a cascade of cell injury and organ system failure. Each year, thousands of children and adults die from mitochondrial disease.
On Feb. 28, physicians and researchers from throughout the world will meet in San Diego for “Mitochondria 2001,” a five-day conference at the Hyatt Regency Islandia, San Diego, hosted by the UCSD School of Medicine, the Mitochondrial Medicine Society, the Mitochondria Research Society, and the United Mitochondrial Disease Foundation. Held concurrently with the professional conference is a program March 2-4 for families impacted by mitochondrial diseases.
They Lost Two Sons to Mitochondrial Disease
Jennifer and Lee DeMeo of Escondido said firstborn Lee Jr. appeared perfectly normal at birth, with a nearly perfect apgar score of 9. By the time he was 15 months, the baby had trouble focusing, then developmental delays. At 2 ½ years, Lee Jr. was in a wheelchair. Although he couldn't walk and never talked, he was a joy to his parents with his laughter and engaging personality. Unexpectedly, Jennifer got pregnant again and delivered Jacob, who they found had mitochondrial disease, like his brother. Only Jacob's case was worse; he died at the age of 8 months. Lee Jr. died in September 1999 at the age of 5.
Each year, nearly 4,000 children are born with mitochondrial disease. The mortality for the most severe forms of mitochondrial disease in childhood is up to 50 percent per year. Some children born with mitochondrial disease do not show symptoms until adulthood when they become disabled and die. Many diseases of aging, such as Parkinson’s, Alzheimer’s, cancer, diabetes and heart disease are thought to involve mitochondrial defects.
Research and treatment for mitochondrial disease is an emerging field in medicine. Although scientists realized in 1963 that mitochondria have their own DNA, it wasn’t until 1988 that the first mitochondrial DNA disorders were identified. Researchers now know there are more than 40 types of mitochondrial disease. Depending upon which cells are affected, symptoms may include loss of motor control, muscle weakness and pain, gastrointestinal disorders and swallowing difficulties, poor growth, cardiac disease, liver disease, diabetes, breathing problems, seizures, visual/hearing problems, lactic acidosis, developmental delays and susceptibility to infection.
Among the leading treatment and research centers in North America are the UCSD Mitochondrial and Metabolic Disease Center, Columbia University in New York, Emory University and Scottish Rite Hospital in Atlanta, Cleveland Clinic in Ohio, Children’s Hospital in Philadelphia and the Hospital for Sick Children in Toronto, Canada.
Richard Haas, M.B., co-director of UCSD’s Mitochondrial and Metabolic Disease Center and conference co-director, says the Mitochondrial 2001 program brings together professionals from a wide variety of medical disciplines. During the conference, these physicians and researchers will finalize an aggressive battle plan to alleviate problems ranging from coding to diagnostic standards and guidelines for new clinical trials.
Wheelchair Bound 13-Year-old Struggles On
Mark Fleming of Los Angeles first noticed Bryan was having a problem when the bright-eyed, physically active toddler was 4 years old. Although he had difficulty walking and swallowing, doctors couldn't determine the cause. Five months later, after a 7 week hospitalization, mitochondrial disease was diagnosed. Bryan was sent home with a ventilator and stomach tube. Mark says it took them 2 to 3 years to teach Bryan how to swallow food again. They finally weaned him from the ventilator during the day, but he needs it at night. About 2 years ago, Bryan became confined to a wheelchair and he has problems talking.
Conference co-coordinator, Robert Naviaux, M.D., Ph.D., co-director of UCSD’s Mitochondrial and Metabolic Disease Center, notes that the extent of mitochondrial disease in the United States is largely unknown. The current estimates are based on studies done in Finland, the Netherlands and Australia. Naviaux is a member of an oversight committee that is developing a national epidemiological study to provide more accurate U.S. data.
“The problem is made worse because you can’t ‘officially’ die of mitochondrial disease in the U.S., even though, in actuality, you die as a result of the disease,” he says.
Because there is no international classification of disease (ICD) code for the vast majority of mitochondrial diseases, death certificates typically list generic codes or “unspecified” as the cause of death. Naviaux notes that accurate ICD codes would provide realistic disease statistics and help in obtaining research funding from organizations such as the National Institutes of Health. In addition, the codes determine health insurance payments. Companies require a code along with a current program of treatment in order to assess proper reimbursement for medical services.
During the Feb. 28-March 4 conference, physicians and researchers will develop a plan to lobby the National Center for Health Statistics in Maryland to ratify a new mitochondrial disease ICD code that has been recommended by the Society for Inborn Metabolic Disorders and the American College of Medical Genetics. In other action at the conference, physicians and researchers will develop uniform lab standards and guidelines for clinical trials.
Mother With Mitochondrial Disease Worries About Her Son
For the past 10 years, Sharon has been in and out of doctors' offices with complaints of muscle weakness. She first noticed a droopy right eye when she was 18; the muscle weakness began a couple years later.By the time she was 30, Sharon could no longer tolerate exercise. Eventually, she found a doctor who diagnosed mitochondrial disease. Although physicians have noted cardiac problems, Sharon says she feels fortunate that she doesn't suffer from the seizures that some mitochondrial disease patients have. Because mitochondrial disease is frequently passed from one generation to another, Sharon is very concerned about her 2-year-old son Liam, who currently shows no signs of the disease.
Based on their experience with more than 400 in-patients and over 1,000 out-patients during the past five years, the UCSD Mitochondrial and Metabolic Disease Center has developed a list of major clinical problems as a starting point for the development of clinical trial guidelines. Because mitochondrial disease is a multi-organ disease, the job of the clinical trial task force will be to develop a priority list of disease abnormalities that are most problematic in children and adults. Then, after the conference, this list will be used to develop protocols for clinical trials internationally.
Noting that the area of mitochondrial disease research currently is not well-funded, Haas hopes that will soon change.
Naviaux believes that findings in mitochondrial medicine may be “no less significant than the formulation of the germ theory by Louis Pasteur and Robert Koch 100 years ago. The recognition that mitochondrial dysfunction can produce disorders ranging from childhood diseases to common disorders of aging is revolutionizing our understanding of many fundamental biological processes and is creating common ground between disciplines in medicine that didn’t exist before. Our knowledge of mitochondrial medicine is growing at such a rapid pace that it is certain there are many surprises yet to come.”
Media Contact: Sue Pondrom
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