Since 1966, California has had a newborn screening program to identify disorders detectable in infants that require immediate medical management. Over time this program has continued to add additional illnesses to the screening program. They have been identified and understood to be candidates for early identification and treatment on a statewide basis. Currently the Newborn Screen evaluates for disorders of metabolism, such as galactosemia and phenylketonuria; disorder of endocrine function such as hypothyroidism or congenital adrenal hyperplasia; and disorders of hemoglobin such as sickle cell disease or thalessemia. These are all examples of a few diseases that are identifiable within the categories of current detection.
Beginning in August 2007 California’s Newborn Screen will also include tests for biotinidase deficiency and cystic fibrosis. All of these exams are completed from blood taken from newborns greater than 12 hours old and less than 12 days of age. The blood is placed on “spots” on a uniform blot for each newborn. This then is sent to a regional neonatal and prenatal screening laboratory. If there are any positives identified, the blood is then forwarded to a confirmatory laboratory designated by the state. If necessary, parents are then referred to specialty care clinics specific to the disorder that has been identified. Usually results of the newborn screen are sent to the family’s pediatrician and should be available approximately two weeks after birth.
Biotinidase deficiency can be classified in both a partial and profound category. To have this enzyme be inactive would result in a problem. Remaining inactive, it cannot release biotin, a vitamin cofactor necessary for organic acid metabolism. California’s screening program is aimed at identifying profound biotinidase deficiency. If left untreated biotinidase deficiency may lead to seizures, vision or hearing problems, skin abnormalities, eventually mental retardation and possibly death.
Cystic fibrosis is an autosomal recessive illness. This means that it requires both parents to have a mutation on chromosome seven for a child to manifest the disease; one copy may result in a carrier status. Cystic fibrosis may lead to damage in multiple organs of the body--particularly the lungs, pancreas and gastrointestinal tract. Affected infants may show slow growth, severe respiratory infections, or abnormal or absent stools.
California’s method will be to apply a four-step screen process where all samples will undergo a common first step. Only those with a positive on this initial step will then proceed to the subsequent more specific screens. In doing this California hopes to detect approximately ninety percent of new cystic fibrosis cases through the newborn screening program.