Pyruvate Dehydrogenase Complex Deficiency (PDC Deficiency)
Description
Pyruvate Dehydrogenase Complex Deficiency (PDC Deficiency) is a rare inherited metabolic disorder that affects the body‘s ability to produce energy from food. This deficiency occurs when the pyruvate dehydrogenase complex (PDC), a group of enzymes essential for this process, is not functioning properly. This can lead to a buildup of lactic acid in the blood, causing various symptoms, particularly in the nervous system.
Genes Involved
PDC Deficiency is caused by mutations in genes that code for the enzymes of the pyruvate dehydrogenase complex. The most commonly affected genes include:
- PDHA1: This gene codes for the E1 alpha subunit of the pyruvate dehydrogenase complex.
- PDHB: This gene codes for the E1 beta subunit of the pyruvate dehydrogenase complex.
- PDHX: This gene codes for the E2 subunit of the pyruvate dehydrogenase complex.
- DLD: This gene codes for the E3 subunit of the pyruvate dehydrogenase complex.
Recognizing the Signs and Symptoms
Symptoms of PDC Deficiency can vary widely depending on the severity of the deficiency. Some common signs include:
- Neurological problems: This may include seizures, developmental delays, muscle weakness, and difficulties with coordination.
- Metabolic acidosis: A buildup of lactic acid in the blood can cause acidosis, leading to rapid breathing, lethargy, and vomiting.
- Feeding difficulties: Infants with PDC Deficiency may have difficulty feeding, leading to poor growth and weight gain.
- Other symptoms: Other possible symptoms include enlarged liver, heart problems, and respiratory problems.
Causes
PDC Deficiency is an inherited disorder, meaning it is passed down from parents to their children. In most cases, the disorder is caused by an autosomal recessive pattern of inheritance. This means that both parents must carry a copy of the mutated gene for their child to inherit the condition. If both parents are carriers, there is a 25% chance that their child will inherit the disorder, a 50% chance that their child will be a carrier, and a 25% chance that their child will not inherit the disorder.
Inheritance/recurrence risk
PDC Deficiency is inherited in an autosomal recessive pattern, meaning both parents must carry a copy of the mutated gene for their child to inherit the condition. If both parents are carriers, there is a 25% chance that their child will inherit the disorder, a 50% chance that their child will be a carrier, and a 25% chance that their child will not inherit the disorder.
