http://www.genetics.com.au/factsheet/fs20.html
Important points
•Newborn Screening (NBS) is a public health funded system for testing newborn babies’ blood for about 30 rare conditions. Some of these conditions can result in physical and/or intellectual problems if not treated promptly, and are often referred to as inborn errors of metabolism
•The conditions tested for include phenylketonuria (PKU), congenital hypothyroidism, cystic fibrosis (CF), galactosaemia and a number of other extremely rare conditions
•This form of testing is known as screening because it involves testing a whole population - in this case, newborn babies. All babies are tested even if they do not have any obvious signs of a condition
•Over 99% of parents agree for their baby to have the NBS test and overall about 1 out of every 1000 babies tested (0.1%) will be diagnosed with a condition as a result of having NBS
•A few days after the baby is born, a blood sample is taken from a tiny prick of the baby’s heel, placed onto a newborn screening card and the card sent to the laboratory
•A series of tests are performed on the dried blood spots. For about 1% of babies’ samples, a test looks at the genetic information (the DNA) in the blood spot to clarify the result
•The parents are not notified if the test result is normal
•Each year newborn screening finds about 90 NSW/ACT babies who have one of these conditions and most of these babies benefit from treatment
•After the dried blood has been tested, it will be stored in the laboratory for varying periods in different states of Australia and in New Zealand to allow for normal quality control practices, and may need to be used for approved research after identifying information has been removed
◦The dried blood spot may be used for further testing at the request of the parent or guardian, to provide new medical information of benefit to the family
◦No further tests will be carried out on any identified stored blood sample by the newborn screening laboratory without written consent from either the parent(s)/guardian(s), the individual if they are old enough, or other lawful authority
What is newborn screening?
Newborn screening refers to the process where babies are given a simple blood test a few days after birth to see if they have a rare genetic or metabolic condition. The conditions screened for in Newborn Screening (NBS) may be life threatening and/or cause intellectual disability.
These conditions are often referred to as ‘inborn errors of metabolism’.
•Metabolism is the chemical process by which food is broken down to make energy available for the normal functioning, growth and development of the body
•Enzymes are proteins that are used by the cells to break down food into a form that can be used
•Errors in metabolism occur when the essential enzymes are absent or malfunction
The aim of NBS is to detect the conditions before the onset of symptoms so treatment can be started early to reduce the effect of the condition.
This form of testing is known as screening because it involves testing a whole population - in this case, newborn babies. All babies are tested even if they do not have any obvious signs of a condition that affects their metabolism.
Newborn screening in Australia and New Zealand
All newborn babies are offered screening in Australia and New Zealand (Australasia).
The NBS policy for the Australasian program is developed by a joint subcommittee of the Human Genetics Society of Australasia (HGSA) and the Division of Paediatrics of the Royal Australasian College of Physicians. Newborn screening is recommended provided that:
1. There is benefit for the individual from early diagnosis
2. The benefit is reasonably balanced against financial and other costs
3. There is a reliable test suitable for newborn screening
4. There is a satisfactory system in operation to deal with diagnostic testing, counselling, treatment and follow-up of patients identified by the test
NBS to detect rare metabolic conditions is an accepted part of neonatal health care in all developed countries. NBS has been established in Australasia since the late 1960s. All Australasian newborn screening programs are fully publicly funded.
•Over 99% of parents agree for their baby to have the newborn screening test
•Overall about 1 out of every 1000 babies tested (0.1%) will be diagnosed with a condition as a result of newborn screening
•Newborn screening is a test provided for all babies free of charge
NBS services in Australasia are provided by five centralised screening laboratories. These are:
•Western Australia
•South Australia (also covers Tasmania and part of the Northern Territory)
•Victoria
•New South Wales (also covers the Australian Capital Territory)
•Queensland (also covers part of the Northern Territory)
How is newborn screening done?
Parents are provided with information and asked for their verbal consent for the blood sample to be taken from the baby by pricking the baby’s heel before the baby leaves hospital. This occurs between 48 and 72 hours after birth. For home births, the test is done on about day 4.
The small amount of blood is placed onto three different spots on a card like the one shown in Figure 20.1 and is sent to a special laboratory.
A series of tests is performed on the dried blood spots. For about 1% of babies’ samples, a test looks at the genetic information (the DNA) in the blood spot to clarify the result.
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