Newborn bloodspot screening aims to achieve early identification of a panel conditions for which early intervention can lead to the elimination or reduction of mortality, morbidity and disability in affected newborns.
The screening program will not detect every affected child, so if one of the screened conditions is suspected, follow-up diagnostic testing should always be considered.
The infant's parent or caregiver will not be notified if the screening result is normal.
Principles of newborn bloodspot screening
The principles of screening include the following:
- Each condition is a serious disorder.
- The condition occurs with sufficient frequency for screening to be cost-effective.
- A cheap reliable screening test is available.
- Early treatment/intervention is beneficial
- Consequences of non-treatment may be severe.
Newborns are routinely screened for the following conditions:
- phenylketonuria (since 1966)
- congenital hypothyroidism (since 1977)
- cystic fibrosis (since 1988)
- various inborn errors of metabolism (since 2002).
In Victoria, 25 conditions are now screened for.
Facts about phenylketonuria:
- There are approximately six cases per year in Victoria.
- It is inherited as an autosomal recessive condition i.e. the parents are not affected but are carriers.
- It is due to a deficiency of the enzyme phenylalanine hydroxylase
- PKU is characterised by an inability to metabolise phenylalanine (an amino acid).
- Accumulation of phenylalanine in the bloodstream leads to neurological complications. If not identified and treated soon after birth it can result in severe, progressive intellectual disability.
- Newborn screening also occasionally detects milder variants and other enzyme deficiencies that secondarily affect phenylalanine metabolism.
- Early detection and treatment of PKU with a diet low in phenylalanine (very low protein and special formula) and/or a drug enables normal growth and development.
- Affected children are managed by the metabolic team at the Royal Children's Hospital and monitored with regular blood tests.
Facts about hypothyroidism:
- Hypothyroidism is usually caused by the absence or poor functioning of the thyroid gland, resulting in reduced production of thyroxine (causing increased thyroid stimulating hormone). Approximately 30 babies are diagnosed with congenital hypothyroidism per year in Victoria.
- It is generally not inherited.
- Lack of thyroxine causes severe intellectual disability and growth problems.
- If detected early and treated with daily oral thyroxine supplements the infant can grow and develop normally.
Facts about cystic fibrosis (CF):
- It is inherited as an autosomal recessive condition.
- Approximately 20 babies are diagnosed with CF per year in Victoria.
- It is a severe genetic condition resulting in the production of thick mucus in the lungs and digestive system, which results in respiratory infections and difficulty in digesting food properly.
- Screening involves a three-step process which can take up to four to six weeks for some babies.
- An enzyme level (immunoreactive trypsinogen) is measured from the neonatal screening card.
- If the enzyme is increased, a genetic test is performed for the most common CF mutations.
- If only one CF mutation is detected, a sweat test is performed to determine whether the baby has CF caused by a second, uncommon CF mutation or whether the baby is a healthy carrier.
- If two CF mutations are detected the baby has CF but a sweat test is still recommended to independently confirm the diagnosis.
- Early detection and treatment improves the health of babies and allows identification of other family members at risk of having a child with CF.
Various inborn errors of metabolism
Screening also identifies a range of metabolic conditions:
- As well as PKU, 22 different metabolic conditions are detected by tandem mass spectrometry testing.
- Approximately 15 babies are diagnosed per year in Victoria.
- MCADD (medium chain acyl CoA dehydrogenase deficiency - see OMIM database), a defect in fatty acid oxidation, is the most frequent.
- There are various treatments including special diets and vitamin supplementation.
- Affected children are managed by the metabolic team at the Royal Children's Hospital, Melbourne.
- New conditions may be considered for addition to the screening panel as technology and medical knowledge advances.
Problems if untreated
|thyroid gland unable to produce thyroid hormones (T3 and T4)||growth failure, intellectual impairment||thyroid hormone supplements|
|abnormal secretions in the body; in particular the lungs and pancreas||impaired digestive and respiratory function, infections and decreased life span||dietary supplements, physiotherapy|
|amino acid disorders*- for example: phenylketonuria (PKU)
|defective enzymes that break down protein||developmental delay, intellectual impairment, seizures||dietary modifications, vitamin supplements|
|fatty acid oxidation disorders*
|defective enzymes that turn fat into energy||muscle problems, poor feeding, vomiting, seizures, sudden death||avoid prolonged fasting, dietary modifications|
It is important that health professionals have prior training for newborn screening. Information, including an e-learning tool is available on the Victorian Clinical Genetics Services website.
Follow these procedures before screening:
- Provide parents with the Newborn Screening Program information brochure. Translated versions are available on the Victorian Clinical Genetics Services website.
- Discuss newborn screening test with parents, using an interpreter if necessary. Advise that participation is voluntary but highly recommended.
- Advise that screening is done for many conditions.
- Explain that a second sample is sometimes required. Reasons include that the sample: was collected too early; was contaminated; or produced an unclear result.
- Most second samples are within the normal range.
- Parents will be contacted to arrange further testing, if required.
- Written consent has been required from parents since 2011.
- Gain signed documentation of consent on the screening card. Parents may consent to the test but refuse use of their infants screening card for de-identified research.
Refusal of screening
If parents refuse the test on behalf of their baby:
- Confirm the parents have received the Newborn Screening Program information brochure and that staff have discussed the test with them.
- Arrange for a medical staff member from the care team to meet with the parents and clearly outline the benefits of the newborn screening test and the risks of not having it done. This is to ensure the parents have a good understanding of possible consequences.
- Parents must be offered the opportunity to have a discussion with a Newborn Screening counsellor if they wish.
- Ring the Victorian Clinical Genetic Services Reception as soon as possible on 03 8341 6201 and ask for a Newborn Screening counsellor.
- Counsellors are best contacted during working hours. An answering machine will take messages.
- The newborn screening card should be filled out with the relevant infant details and signed by the parents, with “No” ticked under “Newborn Screening Consent”. Send the card to the laboratory as for any other screening card. It is important that the laboratory has this record of babies who were not screened.
- Have parent/s complete the decline of screening form and place in the medical record.
- Document the refusal for the test in the Child Health Record book.
- Refusal and nature of discussion should be documented and signed in the mother's and/or baby's file.
- Advise the parents that in the event that the infant becomes unwell, they should seek medical advice and inform their GP/paediatrician that their infant has not had a newborn screening test.
Follow this procedure for sample collection:
- Complete all information on card prior to collection.
- Ensure correct identification of baby.
- Consider giving sucrose for pain management (as per local protocol).
- Collect blood at 48-72 hours after birth (not 'day 2'). This time period represents a balance between allowing enough time for baby's metabolism to establish itself (independent of mother) and avoiding a delay in diagnosis.
- Sample preference is heel prick, followed by samples collected by venepuncture or from a line. If sampling from a tube is unavoidable, please record on the bloodspot card the type of tube used.
- Breast feeding or holding the baby is encouraged
- Cleanse heel as per local protocol. Do not add anything further to heel, such as paraffin.
- Wear gloves.
- Ensure baby is peripherally warm before heel prick.
- Air dry heel or wipe dry with sterile gauze pad.
- Have heel dependent, facing down.
- Identify puncture site - either side of midline, on edge of plantar surface.
- (newborn screening test)
- Press lancet into heel firmly at slight angle.
- Wait for spontaneous free flow of blood, do not squeeze.
- Wipe away first drop with sterile gauze pad.
- Don't rush, allow time for a large drop of blood to form.
- Lightly touch large blood drop to circle on back of card, using a single application of blood for each circle.
- Allow blood to soak through and completely fill circle. A drop that is evenly soaked through and fills two-thirds of the circle is adequate. Three out of the four circles is also adequate.
- Air dry blood spots on a flat non-absorbent surface.
21. Dry for a minimum of four hours away from direct sunlight or heat.
22. Check completeness of identification and sufficient blood.
23. Do not allow cards to come into contact with contaminated skin or surfaces. Do not place cards in plastic as they will sweat.
24. Completed cards should be dispatched to the laboratory using courier (pathology/local) or Express Post without delay after the four-hour drying time.
Other points to consider relating to sampling technique:
- It is important not to squeeze or milk the infant's heel. This will contaminate the specimen with tissue fluids and cause excessive pain.
- Blood spots should not be overlaid on the card. Avoid placing several drops ‘on top of each other’ on the same circle with some time passing between each drop. This results in the first drop starting to dry, preventing subsequent drops from penetrating the filter paper. This can affect screening results.
- Only soak blood from the back of the screening card.
- The circles are a guide only, blood outside the lines is acceptable
- The card should not be rubbed on the heel and the blood spots should not be pressed with fingers. This invariably abrades or compresses the card and reduces its blood holding capacity.
Timing of the test
All newborn infants are screened between 48-72 hours of life regardless of gestational age, weight, commencement of feeding or health status - with the exception of babies receiving blood products (including blood/exchange transfusions, platelets, fresh frozen plasma). See below for instructions regarding these babies.
Further screening requirements
- Infants receiving blood products including blood/exchange transfusions, platelets, fresh frozen plasma (FFP):
- Sample should be obtained if possible prior to the transfusion (even if this is less than 48 hours of age)
- Second sample at least 48 hours after the transfusion is completed when biochemistry is stable
- Third sample is collected three weeks later if first sample taken prior to 48-72 hours as the genetic profile will be stabilised.
- Infants commencing total parenteral nutrition (TPN):
- document this in the box on the screening card
- Infants who have died or are receiving palliative care:
- Screening may help to exclude diseases which could have implications for the family in future pregnancies.
- If the sample is taken after the infant dies, write in red on the screening card that it is a ‘post mortem’ sample as there is a marked difference in the metabolic profile between a live and a deceased infant.
- Infants born after ‘in-utero blood transfusion’:
- Obtain a sample 48-72 hours after birth as this is when the mother’s/donor’s influence on metabolites has ceased.
- Collect a second sample 3 weeks later.
- Extremely low birth weight or premature infants:
- A second sample should be repeated after the initial specimen to detect those infants where immaturity of the hypothalamic-pituitary-thyroid axis may initially mask primary congenital hypothyroidism
- Birth weight < 1,000 g - second specimen collected at three weeks (no later than six weeks)
- Birth weight < 1,500 g - second specimen collected at two weeks (no later than four weeks)
|1st Sample||All infants (including palliative or deceased infants)||48-72 hours|
|2nd Sample||Infants who have received blood transfusions/exchange transfusion/s, platelets, FFP from birth to 72 hours of life||Obtain sample pre-transfusion (even < 48 hours of age), then > 48 hours post transfusion - NB: need to obtain third sample|
|2nd Sample||Premature infants birth weight < 1,000 g||3 weeks|
|2nd Sample||Premature infants birth weight < 1,500 g||2 weeks|
|3rd Sample||Infants who have had blood transfusions within the first 48-72 hours of life||3 weeks post transfusion|
If in doubt or you have any queries, contact the Newborn Screening Laboratory on (03) 8341 6272.
Record date and time sample collected in:
- Child Health Record book
- patient's medical record on the inpatient progress notes/care plan
- add to BOS (if applicable).
Parents may request to have their infant's newborn screening card returned to them after two years, as per the Public Records Act 1973.
Parents may document a request for no secondary access to the card. This prevents the card being used for other purposes, eg development of new tests, ethics approved research.
For further information, contact the Newborn Screening Laboratory.
Victorian Clinical Genetics Services
- Telephone: (03) 8341 6201
- Fax: (03) 8341 6390
Newborn Screening Laboratory
- Telephone: (03) 8341 6272
- Fax: (03) 8341 6339
Newborn Screening Nurse
- Telephone: (03) 8341 6460
- Better Health Channel Fact Sheet on Newborn Screening
- E-learning tool for health professionals
- The OMIM database is a useful starting point for learning more about these conditions.
Watch our video
Monique Cooper shares the story of her son Charlie who lives with a rare health condition, detected through the newborn bloodspot screening program. Download the transcript
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First published: August 2014
Last web update: March 2019
Review by: August 2020
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Page last updated: 12 Nov 2020