What is newborn screening and why should I make sure my baby is tested?

Article written for MidwifeInfo by Judi Tuerck, RN MS, Assistant Professor, Oregon Health & Science University, Child Development and Rehabilitation Center. Email Judi at tuerckj@ohsu.edu.

Newborn screening is a simple blood test, done when the baby is 2-3 days old that checks for a number of serious biochemical birth defects that can cause mental retardation, serious physical problems or even death. Babies with these conditions appear perfectly healthy even though they are getting very sick. By the time symptoms occur, it is usually too late to prevent permanent damage. If infants can be diagnosed and  treated before symptoms occur, in most cases, damage can be totally

A few drops of blood from the baby’s heel are collected on a special filter paper, which is dried and transported to the screening
laboratory. This has traditionally been done via regular U.S. mail, although many hospitals and birth centers now use couriers or express mail to ensure the laboratory receives specimens in a timely manner.

Once in the screening laboratory, testing takes 1-2 days. If an abnormality is found your doctor, midwife, or nurse practitioner will be contacted, usually by phone, with instructions for further testing. This does not necessarily mean your baby has a disorder. However, it is important to get your baby retested quickly so that treatment, if needed, can be started as early as possible.

All fifty states and D.C. screen infants for hypothyroidism, sickle cell disease and hyperphenylalaninemia (PKU) and all but one state (WA) also screen for galactosemia.

Traditionally, screening programs have been limited in the number of disorders they could screen for, as each disease required its own small blood spot. In the last 5-6 years this has changed with the development of tandem mass spectrometry (MS/MS) for newborn screening that enables screening for 25-30 different biochemical disorders using only one blood spot. As of May 2003, 28 screening programs have MS/MS screening in place and this is increasing monthly. A complete list of disorders covered in your
state is available through the National Newborn Screening and Genetic Resource Center at Genes-R-Us. They have links to individual state screening programs as well as to other important information on newborn screening.

is important to remember that not all conditions are detectable using only tandem mass spectrometry. Hypothyroidism, adrenal hyperplasia, sickle cell diseases, galactosemia, cystic fibrosis and biotinidase deficiency require different testing methods.

It is also important to remember that screening programs may count diseases differently. For example, almost all disorders covered by
tandem mass spectrometry have early and late onset versions of the same disease. These are not separate diseases, but usually represent degrees of severity. In one program these may be counted as one disease, others count them as two. In states using MS/MS, depending on the way diseases are counted, programs may screen from 25 to over 55 diseases.

If your state does not yet offer screening with MS/MS and you would like this done, supplementary MS/MS screening is available at commercial laboratories, Baylor University Medical Center, The Mayo Clinic Division of Laboratory Genetics, or NeoGen Screening, Inc.

Approximately 15 states mandate that every infant have two screening specimens collected and every state except CA requires a second specimen if the first is collected before 24 hours of age. The reason this is done is that not all babies with these diseases will have abnormal results on specimens collected in the first few days of life.

However, if specimen collection is delayed many babies with early onset disease will die or be damaged as a result. According to the Academy of Pediatrics the best time for collecting the first specimen is between 48-72 hours of age. Second specimens are generally collected between 10-14 days of age. Different recommendations may exist if your baby’s blood spot is collected at less than 24 hours of age.

Most of these conditions are rare. The chances that any given baby will be affected with one of them are about 1:1,500. Newborn screening has been a routine part of newborn care for over 40 years. Thousands of individuals have had an opportunity for a normal life; millions of dollars have been saved as these individuals no longer need life-long care, and untold pain and suffering have been averted. Make sure your baby is screened!

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