Pyruvate Dehydrogenase Complex Deficiency
Pyruvate dehydrogenase complex (PDC) deficiency is a type of metabolic disease. This means that the body is not able to efficiently break down nutrients in food to be used for energy. Symptoms of PDC deficiency include signs of metabolic dysfunction such as extreme tiredness (lethargy), poor feeding, and rapid breathing (tachypnea). Other symptoms may include signs of neurological dysfunction such as developmental delay, periods of uncontrolled movements (ataxia), low muscle tone (hypotonia), abnormal eye movements, and seizures. Symptoms usually begin in infancy, but signs can first appear at birth or later in childhood. Symptoms may be especially apparent during times of illness, stress, or after meals with high amounts of carbohydrates.
The most common form of PDC deficiency is caused by genetic changes (mutations or pathogenic variants) in the PDHA1 gene. These pathogenic variants are inherited in an X-linked manner. Pathogenic variants in other genes including PDHB, DLAT, PDHX, DLD, and PDP1 can also cause PDC deficiency. These pathogenic variants are inherited in an autosomal recessive manner. PDC deficiency is diagnosed based on laboratory tests including blood tests, analysis of the urine, and brain MRI. The diagnosis can be confirmed by analyzing the pyruvate dehydrogenase enzyme. Treatment for PDC deficiency includes dietary supplementation with carnitine, thiamine, and lipoic acid.
The most common form of PDC deficiency is caused by genetic changes (mutations or pathogenic variants) in the PDHA1 gene. These pathogenic variants are inherited in an X-linked manner. Pathogenic variants in other genes including PDHB, DLAT, PDHX, DLD, and PDP1 can also cause PDC deficiency. These pathogenic variants are inherited in an autosomal recessive manner. PDC deficiency is diagnosed based on laboratory tests including blood tests, analysis of the urine, and brain MRI. The diagnosis can be confirmed by analyzing the pyruvate dehydrogenase enzyme. Treatment for PDC deficiency includes dietary supplementation with carnitine, thiamine, and lipoic acid.