Newborn Screening and Medications

The first few days of a baby’s life are very hectic! It often seems that doctors and nurses are constantly running tests or giving medications in these first days, and many parents wonder why all of these things are done, and, more importantly, are they necessary. The answer is, YES! All of the things we do in those first few days are important things we have learned we can do to help insure the health of your infant. Let’s discuss each portion one by one.

Erythromycin ointment: newborns are susceptible to infection in the early months. In the first 1-2 weeks after birth, this includes severe bacterial infections of the eyes (pink eye). The bacteria that cause pink eye in the newborn are very different than those that cause pink eye in older children. In infants, the most common causes for pink eye are Chlamydia and Neisseria gonorrhea. Both of these infections can cause permanent vision loss in infants. By applying this antibiotic ointment once within the first few hours after birth, we can prevent these infections from occurring. The most common side effect of the erythromycin ointment is some mild irritation around the skin of the eye that resolves on its own, without intervention. This does not commonly occur, and is not harmful.

Vitamin K: Our bodies obtain the majority of the vitamin K that they use from natural bacteria that inhabit our intestines. These bacteria produce vitamin K which our bodies store for use. Infants are born without any intestinal bacteria and so are vitamin K deficient when they are born. Why does this matter? Vitamin K is a key factor in our clotting system, that is, our body’s natural ability to stop bleeding. Before the initiation of vitamin K shots at birth infants were at risk for severe bleeding, including intracranial (inside the brain) bleeding within the first several weeks of life. Unfortunately, breast milk has very little vitamin K in it, and formula has only slightly more. Vitamin K deficient bleeding (VKDB) or “hemorrhagic disease of the newborn”, as it is more commonly known, can occur as early as the first day of life, but usually between days 2-7. The risk can persist up to 6 months for infants who do not receive vitamin K injection at birth and are exclusively breast fed due to low amount of vitamin K found in breast milk.

Some parents express concern based on a study that came out in the 1990’s suggesting a relationship between injectable administration of vitamin K and childhood cancer.[ However, poor methods and small sample sizes led to the discrediting of these studies and a review of the evidence published in 2000 by Ross and Davies found no link between the two. Multiple studies since that time have shown no association between vitamin K and cancer.

Newborn screening; the PKU test: The PKU test is done to identify a number of genetic/metabolic diseases that can seriously affect an infant’s long-term health, development and survival. Metabolic diseases are diseases they lead to an inability to process certain types of energy (for instance, an inability to process certain proteins or fats) If we identify these diseases early in life, we can often make appropriate interventions, sometimes a simple as using a specialized formula, and prevent children from developing serious and permanent brain injury.

This testing starting in the 1960’s and it is called the PKU test after the original disease for which is tested, phenylketonuria. Today, all states screen for a different panel of tests. To see what is tested in each state you can go to this website:

This testing is performed on blood. We take small samples of an infant’s blood on a special piece of filter paper. This paper is then tested for things including hypothyroidism, sickle cell disease, phenylketonuria, and many other diseases. There are no risks associated with PKU testing, and the benefits are astounding! For instance, before newborn screening for thyroid disease, children with congenital hypo (low) thyroidism would develop permanent severe developmental delay and mental retardation. Today, we can identify these babies before they show any symptoms, initiate the right treatment, and they have perfectly normal, healthy development!

Newborn hearing tests: Much like the PKU testing, we realized that many infant’s who had congenital hearing loss were going unrecognized in early infancy, and that this was leading them to have significant delays in their speech development. With the advent of universal newborn hearing tests, we can now identify infants with hearing loss within the first few days to weeks of life and initiate hearing support that allows them to have more normal speech development. Newborn hearing screening is performed by placing small “headphones” over the baby’s ears and a small set of clicks is played via a microphone and the inner ear’s response to these sounds is tested. This is called the “Otoacoustic emissions” test. Some hospitals may use testing called “ABR” testing (auditory brainstem response). In this test small electrodes are placed on the infant’s head and the brain’s response to sound is tested. Both of these tests are completely painless, and in fact are often performed with the infant sound asleep. They have no risks associated with them at all, and cause the infant absolutely no discomfort.