Newborn Screening Ontario (NSO) offers screening for serious diseases to all babies born in Ontario. Individually, these diseases are rare, but as a group, they will affect approximately 150 out of 140,000 babies born in the province each year. These babies appear normal at birth and, without newborn screening, might not be identified to have one of these diseases before irreversible damage has occurred. Early identification of these diseases allows treatment that may prevent growth problems, health problems, mental retardation, and sudden infant death.
NSO is housed at the Children's Hospital of Eastern Ontario (CHEO) in Ottawa, where all the screening tests are performed. NSO at CHEO began receiving samples on April 3, 2006 and began screening for phenylketonuria (PKU), congenital hypothyroidism, and MCADD (medium chain acyl-CoA dehydrogenase deficiency).
On August 8, 2006, the program expanded further to include screening for 18 additional metabolic conditions, including other fatty acid oxidation defects (FAODs), amino acidemias (AAs), and organic acidemias (OAs). NSO began screening for hemoglobinopathies (HbSS, HbSC, and HbS/▀-thalassemia) on November 24, 2006. On February 28, 2007, NSO began screening for biotinidase deficiency and galactosemia. We began screening for congenital adrenal hyperplasia (CAH) on May 14, 2007, and added screening for cystic fibrosis (CF) on April 7, 2008. Screening for the most recent addition, Severe Combined Immune Deficiency (SCID), began on August 12, 2013.
As a provider of antenatal or newborn care, you should discuss newborn screening with your patient. Information about newborn screening should also be discussed with prospective parents in their prenatal education classes. To assist with patient education, pamphlets about newborn screening are available in many different languages. There is also a video available (to view, please click here). If you have any questions about newborn screening or educational resources available, please contact NSO.
A newborn screening specimen card should be completed between one day (24 hours) and seven days after the birth of the infant, ideally, between two days (48 hours) and three days (72 hours) after birth. If tested before 24 hours of age, the baby's health care provider should repeat the test within five days, at the first postnatal checkup. Blood spots from infants are collected using the heel-prick method, which is detailed on the back of the specimen card. The parent should be given an information letter that includes a reference number in the top right hand corner. This number can be used to link to the baby's sample.
A health care provider will fill out demographic information about the baby and the baby's mother/guardian on the newborn screening card. This information allows NSO to correctly interpret the baby's results, and, in the event that the baby screens positive for a disease, it will allow the health care providers coordinating follow-up to contact the parent/guardian quickly to retrieve the baby.
As a health care provider, it is important that you emphasize to parents/guardians that newborn screening is part of their baby's routine care and could save their baby's life and/or prevent serious health problems. The vast majority of parents agree to have their baby screened. Parents/guardians may choose to decline newborn screening for their baby. You should discuss this decision with them, and you should document this decision in the baby's medical record. Some health care providers will ask parents/guardians to sign a form indicating that they have refused this testing for their baby.
The Newborn Screening Sample
It is critical that NSO receive the newborn screening specimen card as soon as possible after the blood spots are collected. Therefore, the cards should be sent no later than 24 hours after collection and, ideally, as soon as the blood spots are dry (four to six hours after collection). Babies with some of the diseases screened will start to become ill and may suffer irreversible damage soon after birth.
The hospital or health care provider will send the baby's sample to NSO using the Purolator courier service. When the sample is received, the blood spot is tested and the demographic information from the newborn screening card is entered into a database. This database connects the baby's information with the results of the screening tests, and also serves as a way to store the baby's newborn screening result.
The results of the screening tests are reviewed by doctors to determine if the baby has a lower risk of having a disease ("screen negative") or a higher risk of having a disease ("screen positive").
Screen Negative Results (low risk)
If the baby is "screen negative", he or she has a low risk of having any of these diseases. In this case, a report is mailed to the hospital or health care provider that sent in the baby's sample. This report will NOT contain information about the baby's carrier status for the hemoglobinopathies.
If the baby's sample is unsatisfactory (for example, if it was taken too early, or if there was not enough blood to do the testing), NSO will contact the hospital or health care provider that sent in the sample and ask them for a new sample. The health care provider who submitted the sample should call the patient to tell them that the baby's test needs to be repeated and make arrangements for another sample to be taken.
Screen Positive Results (increased risk)
If the baby is screen positive, this does NOT mean that the baby has a disease; however, it does mean that the baby has an increased chance to have a disease. A doctor, genetic counsellor, or nurse from NSO may contact the baby's parents/guardians or health care provider directly about the result. An NSO physician will refer the baby to physicians at a regional treatment centre for follow-up diagnostic testing to determine if the baby truly has the disease. In some cases, NSO staff work directly with health care providers and families to arrange testing.
The treatment centre physicians will provide the referring physician at NSO with follow-up information about the baby, as is the case for any medical referral. This includes medical information, which tests were done, the results of those tests, and whether or not the baby truly has the disease (for an example of a Diagnostic Evaluation Form, please click here).
This feedback allows NSO to make sure that screen positive babies receive appropriate and timely care. It is also important for you to note that the information from the evaluation form will be used to make sure that NSO provides quality service to the baby and all babies born in Ontario. The NSO health care providers review this information and may contact you, the patient, or the regional treatment centre if we have questions about the baby's care. Parents/guardians may choose not to share this information, in which case, they should be encouraged to discuss this with their health care provider or contact NSO.
As with all screening tests, false positive and false negative results occur in newborn screening. False positives increase parental anxiety, while false negatives will give a misleading sense of reassurance. If a baby in your care displays symptoms of a particular disease, the child should be investigated and managed appropriately regardless of the results of the newborn screen. The relevant specialist should be contacted immediately for further advice.
There is wide variation in the clinical presentation of the diseases that the newborn screen detects. Therefore, some affected individuals ľ babies who have had diagnostic testing indicating that they have a particular diseaseľ will remain asymptomatic or have very mild symptoms, even without treatment.