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Leigh's Disease
What is Leigh's Disease?
Leigh's disease is a rare inherited neurometabolic disorder that affects the
central nervous system. This progressive disorder begins in infants between the
ages of three months and two years. Rarely, it occurs in teenagers and adults.
Leigh's disease can be caused by mutations in mitochondrial DNA or by
deficiencies of an enzyme called pyruvate dehydrogenase. Symptoms of Leigh's
disease usually progress rapidly. The earliest signs may be poor sucking
ability, and the loss of head control and motor skills. These symptoms may be
accompanied by loss of appetite, vomiting, irritability, continuous crying, and
seizures. As the disorder progresses, symptoms may also include generalized
weakness, lack of muscle tone, and episodes of lactic acidosis, which can lead
to impairment of respiratory and kidney function. In Leigh’s disease, genetic
mutations in mitochondrial DNA interfere with the energy sources that run cells
in an area of the brain that plays a role in motor movements. The primary
function of mitochondria is to convert the energy in glucose and fatty acids
into a substance called adenosine triphosphate (ATP). The energy in ATP drives
virtually all of a cell's metabolic functions. Genetic mutations in
mitochondrial DNA, therefore, result in a chronic lack of energy in these cells,
which in turn affects the central nervous system and causes progressive
degeneration of motor functions.
There is also a form of Leigh’s disease (called X-linked Leigh's disease)
which is the result of mutations in a gene that produces another group of
substances that are important for cell metabolism. This gene is only found on
the X chromosome.
Is there any treatment?
The most common treatment for Leigh's disease is thiamine or Vitamin B1. Oral
sodium bicarbonate or sodium citrate may also be prescribed to manage lactic
acidosis. Researchers are currently testing dichloroacetate to establish its
effectiveness in treating lactic acidosis. In individuals who have the X-linked
form of Leigh’s disease, a high-fat, low-carbohydrate diet may be recommended.
What is the prognosis?
The prognosis for individuals with Leigh's disease is poor. Individuals who
lack mitochondrial complex IV activity and those with pyruvate dehydrogenase
deficiency tend to have the worst prognosis and die within a few years. Those
with partial deficiencies have a better prognosis, and may live to be 6 or 7
years of age. Some have survived to their mid-teenage years.
What research is being done?
The NINDS supports and encourages a broad range of basic and clinical
research on neurogenetic disorders such as Leigh's disease. The goal of this
research is to understand what causes these disorders and then to apply these
findings to new ways to diagnose, treat, and prevent them.
Organizations
Epilepsy Foundation
8301 Professional Place
Landover, MD 20785-7223
postmaster@efa.org
http://www.epilepsyfoundation.org
Tel: 301.459.3700 800.EFA.1000 (332.1000)
Fax: 301.577.2684
National Organization for Rare Disorders (NORD)
P.O. Box 1968
(55 Kenosia Avenue)
Danbury, CT 06813-1968
orphan@rarediseases.org
http://www.rarediseases.org
Tel: 203.744.0100 Voice Mail 800.999.NORD (6673)
Fax: 203.798.2291
United Mitochondrial Disease Foundation
8085 Saltsburg Road, Suite 201
Pittsburgh, PA 15239
info@umdf.org
http://www.umdf.org
Tel: 412.793.8077
Fax: 412.793.6477
Source: National Institutes of Health; National Institute of
Neurological Disorders and Stroke
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