Starting on the right foot with Newborn Screening
Programs that screen newborn babies for selected genetic and metabolic diseases are vital to the health of infants. Without these screenings, babies would be at risk for developing severe illnesses that could cause brain damage or death. With early detection and treatment, however, many of these diseases can be managed successfully. Newborn screenings are thus an important part of providing comprehensive care for all infants.
How it works
Newborn screening tests for any disorders involving the metabolism of nutrients in the body. These disorders can lead to abnormalities in body chemistry, which can cause various diseases or disorders. Most metabolic disorders are caused by a lack of a particular enzyme, which in turn prevents the body from breaking down a certain nutrient. This can then lead to problems with the body’s ability to derive the benefit of this nutrient, which can result in a disease or disorder of body chemistry.
As most affected children show no sign of the disease at birth, the tests have to be done within 24 – 72 hours of birth. Newborn screening tests are therefore designed to pick up these diseases and disorders before any harmful effects set in,
The screening process
These diseases are rare. However, since we do not know which child may be at risk of a metabolic disease, international practice recommends that all children undergo newborn screening.
By testing all children, we are assured of finding the few that are affected, for whom early detection and treatment of disease is vital.
The ideal time is between 24 and 72 hours after the birth but up to a week after birth is still acceptable. The baby needs to have had a few feeds and started the digestion and metabolism of proteins, carbohydrates, and fats (all found in breast milk and formula milk to bring the disorder to light.) Tests done outside the ideal timeframe may still be useful, but they become less accurate.
- The test must be done 1-3 days after birth.
- Ask your paediatrician to order the test.
- A trained sister will come to you to take the test.
- A few drops of blood will be taken from your baby’s heel. In some cases, instead of a heel prick, blood may be drawn from the baby’s vein and put on a special blotting card.
- The card will be couriered to the Centre for Human Metabolomics at the North-West University where the testing will be done.
- Your paediatrician will contact you with the result.
If something is found to be abnormal with the results, a repeat test and sometimes additional blood and urine tests may be required. The request for further testing must not alarm you as it does not mean that there is something wrong with your baby.
Often, when the first test suggests a problem, the results cannot be considered final until a repeat test is done. This requires a new blood sample. Your paediatrician will discuss the need for further tests with you.
You will be notified of the result within 7 working days of the test being done.
If a test comes back positive for any of the disorders, your paediatrician will contact you immediately. Each disorder is treatable in its own way even though they are not curable. Your paediatrician will guide you through the explanation of the disease and the ways in which it can be treated. Next Biosciences is also able to organise a genetic counsellor to counsel you about the implications of the disease.
In most instances treatment consists of dietary modifications, dietary supplementation, hormones and sometimes medication. If your baby has one of these conditions, it is very important that treatment is started as soon as possible.
The baby will feel a little discomfort during the blood collection procedure and may cry a bit. The testing is not harmful at all.
24 conditions are screened for in the Newborn Screen, including:
Amino Acid Disorders
- Citrullinaemia, Type 1
- Classic Phenylketonuria
- Maple Syrup Urine Disease
- Tyrosinaemia, Type 1
Organic Acid Disorders
- 3-Hydroxy-3-Methyglutaric Aciduria
- 3-Methylcrotonyl-CoA Carboxylase Deficiency
- Glutaric Acidaemia Type I
- Holocarboxylase Synthase Deficiency
- Isovaleric Acidaemia
- Methylmalonic Acidaemia (Cobalamin disorders)
- Methylmalonic Acidaemia (methylmalonyl-CoA mutase)
- Propionic Acidaemia
- B-Ketothiolase Deficiency
Disorders of Fatty Acid Oxidation
- Carnitine Uptake Defect/Carnitine Transport Defect
- Long Chain 3-Hydroxyacyl-CoA Dehydrogenase Deficiency
- Multiple Acyl-CoA Dehydrogenase Deficiency
(MADD or Glutaric Acidaemia Il)
- Medium-chain Acyl-CoA Dehydrogenase Deficiency
- Very Long-chain Acyl-CoA Dehydrogenase Deficiency
Disorders of Carbohydrate Metabolism
- Classic Galactosaemia
- Congenital Adrenal Hyperplasia
- Primary Congenital Hypothyroidism
- Biotinidase Deficiency
- Cystic Fibrosis