Newborn Screening

Newborn Screening Test (NBS) is the baby’s first test that

Looks for developmental, genetic, and metabolic disorders in the newborn baby.
The test is done after 24-48 hours a baby is born. It is even possible for older babies to be screened up to the age of 2.
NBS test is done on babys blood and urine samples to test for 50 different genetic conditions.
NBS covers 7 metabolic disorders, 49 parameters of Amino Acids, Organic Acids, and fatty Acid Disorders. The technology used for performing these tests is known as Tandem Mass Spectrometry.
Newborn hemoglobinopathies screening may be considered an additional strategy within a prevention program in non-endemic countries, for sickle cell disease.
NBS is an integral part of neonatal care for early treatment of the affected newborn rather than prospective primary prevention.

Retrospective primary prevention for the parents who are at risk and had an affected child.
Prospective primary prevention for those couples who are at risk and had a carrier child. Health gain in the treatment of an anemic carrier and accident prevention particularly during
anesthesia for HbS carriers Long-term information for healthy carriers for future partner testing and reproductive choices.

Early signs of newborn hemoglobinopathy include:

Newborn screening includes tests that are easy to diagnose and treatment is possible if detected early.

These tests include

NBS can detect various metabolic disorders of the newborn such as

Phenylketonuria (PKU)
Methylmalonic academia
Maple syrup urine disease (MSUD)
Tyrosinemia
Citrullinemia
Medium-chain acyl CoA dehydrogenase (MCAD) deficiency
Hormonal problems such as congenital hypothyroidism and congenital adrenal hyperplasia.
Haemoglobinopathies like sickle cell disease, hemoglobin SC disease, and beta-thalassemia

Other rare but serious medical problems detected in newborn screening are:

NBS has shown immeasurable benefits for potentially disabling or fatal diseases like PKU.
Pre-symptomatic diagnosis through newborn screening can prevent this anxiety and also the costs associated with seeking a diagnosis for unexplained symptoms.
Benefits to society, permitting knowledge about a particular disorder such as incidence,
Natural history, phenotypic spectrum, and optimal treatment algorithms, thereby allowing more individuals who are affected with these disorders to benefit from this information.
DBS retention and use for quality assurance provide significant benefits by improving the precision and accuracy of testing, decreasing false-positive and false-negative results.
NBS for sickle cell anemia and other hemoglobinopathies are done using HPLC or isoelectric focusing. Results are ready by the time a baby is 5–7 days old.
Potential to increase the performance metrics of testing and target disorders that may not be amenable to biochemical testing.

Sample for NBS is either dry blood or fresh cord blood

Fresh cord blood, analyzed within 24 hours, gives the best separation patterns. The fresh cord blood samples can either be loaded directly from the tube or be haemolysed first. However, fresh cord blood is not always available.
An alternative of choice, suitable for large-scale regional or national screening programs is dry blood samples collected from a heel-prick within one week after birth. A few drops are absorbed on filter paper (Guthrie card) and sent by mail to the reference laboratory serving the region.

Screenings are done using the following methods:

Blood test
A few drops of blood are taken from the babys heel and are sent to a lab for analysis. This is often read by the time the newborn is around five to seven days old.
Hearing test
A health care provider will place a tiny earpiece or microphone in the infant's ear. Another method uses electrodes that are put on the baby's head while the baby is quiet or asleep.
CCHD screen
A provider will place a small soft sensor on the baby's skin and attach it to a machine called an oximeter for a few minutes. The oximeter will measure the babys oxygen levels in the hand and foot.

Risk of false-positive results since cutoff thresholds are generally set low to avoid missing affected infants leading to unnecessary cost and treatment.
The risk involved in screening for new diseases where the phenotypic spectrum is not fully understood before the ons et of screening.
Risk of potential harm from erroneous over-treatment for diseases like PKU.
Risks associated with screening for mild or later-onset diseases that may not manifest for years after screening, such as some of the lysosomal storage disorders.
Detection of maternal deficiencies from the transfer of metabolites to the baby either in the uterus or through breastfeeding.
Lack of communication and education about the use of DBS may contribute to a sense of public mistrust.