There are over a dozen types of Fatty Acid Oxidation Disorders (FAODs) based upon which enzyme is affected that coverts fat to energy. Determining the specific enzyme that is affected helps guide the treatment.
Infants undergo a newborn screening test during the first few days of their life using a dried blood spot specimen obtained in the nursery. These screenings test for a group of health disorders that aren’t otherwise detectable at birth and include disorders such as sickle cell anemia, cystic fibrosis and FAODs. Newborn screening occurs in every state, however the disease panel can differ from state to state.
Since the turn of the century, close to 4 million babies undergo newborn screening annually in the U.S. Since 1990, the use of a scientific technique know as tandem mass spectrometry has enabled healthcare providers to detect a greater number of metabolic disorders including over a dozen FAODs. Early detection provides the best opportunity to identify affected babies and ensure the best outcome.
Certain FAOD diagnoses have signature biochemical characteristics that are identified immediately by the newborn screen. An abnormal result on a newborn screening test does not necessarily guarantee that a child has a particular condition, but it is critical that you follow up with your physician for more extensive confirmatory testing. Typically, additional blood and urine testing must be done to confirm the specific FAOD diagnosis. The most common blood test performed for confirmation testing is the blood acylcarnitine test; the specific pattern of acylcarnitine can differentiate one disorder from the next. Sometimes, skin cells must be cultured or DNA tests in blood performed to show the specific enzyme deficiency.
For adults and children who never underwent newborn screening, biochemical or genetic testing can help pinpoint a diagnosis. Genetic testing identifies alterations in the genes associated with the FAOD enzymes. Siblings of affected individuals, whether or not they are symptomatic, should be tested. FAODs are inherited in an autosomal recessive manner, meaning that an affected child receives a genetic mutation from each parent. Parents are non-symptomatic carriers who have a 25% chance in every pregnancy of having an affected child.
Important organs such as the heart, liver or muscles may be affected by FAODs and require monitoring and specialized care from a cardiologist, neurologist and/or gastroenterologist.