Question: What is (are) pyruvate dehydrogenase deficiency ?
Answer: Pyruvate dehydrogenase deficiency is characterized by the buildup of a chemical called lactic acid in the body and a variety of neurological problems. Signs and symptoms of this condition usually first appear shortly after birth, and they can vary widely among affected individuals. The most common feature is a potentially life-threatening buildup of lactic acid (lactic acidosis), which can cause nausea, vomiting, severe breathing problems, and an abnormal heartbeat. People with pyruvate dehydrogenase deficiency usually have neurological problems as well. Most have delayed development of mental abilities and motor skills such as sitting and walking. Other neurological problems can include intellectual disability, seizures, weak muscle tone (hypotonia), poor coordination, and difficulty walking. Some affected individuals have abnormal brain structures, such as underdevelopment of the tissue connecting the left and right halves of the brain (corpus callosum), wasting away (atrophy) of the exterior part of the brain known as the cerebral cortex, or patches of damaged tissue (lesions) on some parts of the brain. Because of the severe health effects, many individuals with pyruvate dehydrogenase deficiency do not survive past childhood, although some may live into adolescence or adulthood.
Source: GHR

Question: How many people are affected by pyruvate dehydrogenase deficiency ?
Answer: Pyruvate dehydrogenase deficiency is believed to be a rare condition; however, its prevalence is unknown.
Source: GHR

Question: Is pyruvate dehydrogenase deficiency inherited ?
Answer: Pyruvate dehydrogenase deficiency can have different inheritance patterns. When the condition is caused by mutations in the PDHA1 gene, it is inherited in an X-linked recessive pattern. The PDHA1 gene is located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation would usually have to occur in both copies of the gene to cause the disorder. However, in pyruvate dehydrogenase deficiency, one altered copy of the PDHA1 gene is sufficient to cause the disorder, because the X chromosome with the normal copy of the PDHA1 gene is turned off through a process called X-inactivation. Early in embryonic development in females, one of the two X chromosomes is permanently inactivated in somatic cells (cells other than egg and sperm cells). X-inactivation ensures that females, like males, have only one active copy of the X chromosome in each body cell. Usually X-inactivation occurs randomly, such that each X chromosome is active in about half of the body cells. Sometimes X-inactivation is not random, and one X chromosome is active in more than half of cells. When X-inactivation does not occur randomly, it is called skewed X-inactivation. Research shows that females with pyruvate dehydrogenase deficiency caused by mutation of the PDHA1 gene have skewed X-inactivation, which results in the inactivation of the X chromosome with the normal copy of the PDHA1 gene in most cells of the body. This skewed X-inactivation causes the chromosome with the mutated PDHA1 gene to be expressed in more than half of cells. When caused by mutations in the other associated genes, pyruvate dehydrogenase deficiency is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
Source: GHR

Question: What are the treatments for pyruvate dehydrogenase deficiency ?
Answer: These resources address the diagnosis or management of pyruvate dehydrogenase deficiency: - Genetic Testing Registry: Pyruvate dehydrogenase E1-beta deficiency - Genetic Testing Registry: Pyruvate dehydrogenase E2 deficiency - Genetic Testing Registry: Pyruvate dehydrogenase E3-binding protein deficiency - Genetic Testing Registry: Pyruvate dehydrogenase complex deficiency - Genetic Testing Registry: Pyruvate dehydrogenase phosphatase deficiency These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
Source: GHR