In the United States, 3.8 million babies were born in 2017 (Martin, Hamilton, Osterman, Driscoll, & Drake, 2018). Of these births, the US Department of Health and Human Services (HHS, 2017) reports that most states record at least a 99.9% participation rate in screening programs for genetic and early development disorders. Each state’s screening program varies somewhat in the disorders included in their panel; however, every state includes at least 29 core conditions that were put forward in the Recommended Uniform Screening Panel (RUSP) by the Federal Advisory Committees (2019). In most states, the standard newborn screening includes at least a heel-stick, pulse oximetry, and hearing test. In some states, a second blood draw is done to screen for false positives between ten days and two weeks after the original draw. As a result of these screenings, 1 in 300, or 12,500 newborns a year, are diagnosed with one of these core conditions (HHS, 2017). Of these conditions, the most commonly identified include phenylketonuria, cystic fibrosis, congenital hypothyroidism, sickle cell disease, critical congenital heart disease, and hearing loss (National Institutes of Health [NIH], 2017). For the purpose of this module, we will focus on these most commonly identified conditions, although the RN working with a newly diagnosed infant should obviously take the time necessary to educate themselves on the remaining, less-common conditions, so as to better educate and equip new parents.
Phenylketonuria (PKU) is one of the most common genetic disorders identified in the newborn screening, accounting for between 1 in 10,000 to 1 in 15,000 births in the US (NIH, 2019). In this condition, the amino acid phenylalanine (Phe) found in protein cannot be digested by the affected person due to a lack of the metabolizing enzyme in the liver, phenylalanine hydroxylase. This results in elevated levels of Phe in the blood (National Organization for Rare Disorders [NORD], 2019). The original screening test developed by Dr. Guthrie in 1960 is included in the 29 tests recommended by RUSP and is run from the blood obtained in the heel-stick (HHS, 2017). Unfortunately, infants with this condition typically do not show any symptoms until they are several months old. If unidentified and untreated, the condition leads to permanent intellectual disability with behavioral issues, delayed development, growth delay, microcephaly, seizures, or psychiatric illness (NORD, 2019). Prior to 1960, when a reliable test and treatment measures were developed, PKU was not identified until after permanent brain damage with developmental delay had occurred (Berry et al., 2013). Thus, the availability of newborn screening has drastically reduced observed symptoms of PKU, and the severe effects are almost never seen in the US today (NORD, 2019).
Treatment for PKU is lifelong adherence to a Phe-restricted diet with a goal of maintaining a Phe blood level between 120-360 µmol/L. A Phe-restricted diet consists of abstaining from animal protein, most legumes, and nuts. They must limit their intake of bread, pasta, and rice or consume only low-protein variations of those foods. People (both infants and adults) with PKU also need to supplement their diet with amino acid-based, Phe-free formula or medical foods to maintain energy with adequate protein, vitamins, and minerals while adhering to a Phe-restricted diet (Berry et al., 2013).
Implications for Nursing
Nurses who interact with the parents of patients newly diagnosed with PKU need to be aware of the multiple resources available for these patients, as external support is key in the optimal health and wellness of chronically ill patients. The nurse should also be knowledgeabe on the long-term effects of PKU and the potential impact such a diagnosis will have on the lives of the patient and their family. Nurses should stress the need for ongoing follow up and management with a metabolic clinic. New studies show that as little as 50% of patients with PKU are followed lifelong, despite the fact that consistent management of the condition and adherence to a Phe-restricted diet has been shown to limit the effect on IQ tests and cognitive screens later in life (Berry et al., 2013). Resources for families of infants diagnosed with PKU include the National Organization for Rare Disorders, Children’s PKU Network, National PKU Alliance, and National PKU News (NORD, 2019).
Congenital hypothyroidism affects as many as 1 in 2000 to 1 in 4000 births in the US each year. This condition is caused by an under-developed, malfunctioning, or absent thyroid, and is present at birth. In contrast to developed thyroid disease, which manifests later in life, effects of congenital hypothyroidism manifest almost immediately after birth, and treatment should start within the first two weeks of life to prevent developmental delay (NIH, 2019a). Congenital hypothyroidism affects phenotypically female infants twice as often as phenotypically male infants for reasons that are as of yet unidentified (Adler, 2019). Symptoms of congenital hypothyroidism may include hypo-activity and somnolence in the newborn, along with constipation and difficulty feeding (NIH, 2019a). They may also exhibit macroglossia, large fontanelles, prolonged jaundice, puffy facies, or umbilical hernias (American College of Medical Genetics, 2012). If left untreated, congenital hypothyroidism can lead to permanent intellectual disability and impaired growth (NIH, 2019a).
Just as in adults, congenital hypothyroidism is identified by testing for elevated levels of thyroid stimulating hormone in the blood, and as with PKU, this test is included in the panel recommended by RUSP and taken from the heel-stick blood draw. If this test is outside of normal limits, the patient should be referred to a specialist, who may order additional tests to confirm the diagnosis. Confirmatory testing is usually comprised of total T4 and T3 resin uptake (American College of Medical Genetics, 2012). Congenital hypothyroidism is treated by medical supplementation of the thyroxine that the patient’s own thyroid is not making (Adler, 2019). Infants who start treatment within the first two weeks of life will develop normally, although regular follow-up with a specialist is necessary to ensure that the patient’s levels stay within normal limits (Adler, 2019; NIH, 2019a).
Implications for Nursing
The nurse working with infants diagnosed with congenital hypothyroidism should be aware of the following when caring for these patients and their families: parents should be reassured that as long as their child is promptly treated, they will not have any permanent intellectual disability or developmental delay. Due to the time-sensitive nature of the treatment of congenital hypothyroidism, parents should be made aware of their infant’s results as soon as possible and assisted in making an appointment with a specialist to obtain confirmatory testing and the timely initiation of treatment (American College of Medical Genetics, 2012). The nurse should educate parents that this is a disease that will require lifelong, long-term medical treatment, so they are aware that frequent follow-up will be necessary (Adler, 2019). Resources for parents of infants with congenital hypothyroidism include the American Thyroid Association and the MAGIC Foundation (NIH, 2019a).
Cystic fibrosis (CF) is a disorder of the body’s mucus production, causing abnormally thick and sticky mucus, leading to increased respiratory and digestive disorders. This disease can lead to permanent lung damage with frequent infections, and contributes to a shorter-than-average life expectancy (NIH, 2019c). Symptoms of CF in an infant include salty skin, frequent cough, wheezing, meconium ileus, and failure to thrive (American College of Medical Genetics, 2010). According to the NIH (2019c), CF affects as many as 1 in 2500 to 1 in 3500 white newborns a year in the US. The disease is significantly less common in other populations in the US, affecting only around 1 in 17,000 African Americans and 1 in 35,000 Asian Americans (NIH, 2019c). This is yet another test included in the recommended panel by RUSP and is again identified by the heel-stick; however, the actual type of test run can vary from state to state. Like congenital hypothyroidism, a positive newborn screen for possible CF requires several confirmatory follow-up tests with a specialist. These usually consist of a sweat test or a sweat chloride test but can include a genetic test as well (American College of Medical Genetics, 2010). Unfortunately, unlike PKU or congenital hypothyroidism, the effects of CF cannot be circumvented by early diagnosis and treatment at this time. Early diagnosis and intervention are associated with longer life and better quality of life in patients with the disease (Cordeiro et al., 2018). Advances in the treatment available for CF coupled with earlier identification and interventions have increased the life expectancy of an affected patient from early teens to an average of 40 years of age (NIH, 2019c).
Implications for Nursing
The nurse working with newborns and infants should be aware that not all gene variations that can cause CF are tested for in every state. If an infant presents with symptoms indicative of CF (frequent lung infections, digestive problems, failure to thrive, wheezing, etc.), they should still be referred for a sweat test or genetic testing. Conversely, some states only test for elevated levels of immunoreactive trypsinogen (IRT), which is not completely specific to a diagnosis of CF and thus should be referred for a sweat test to rule out a false positive (Kaneshiro, 2018). Nurses should also be aware that there are many resources available for patients who have CF and their families, including the American Lung Association, the Cystic Fibrosis Foundation, Cystic Fibrosis Research Inc, and the National Organization for Rare Disorders, among others (NIH, 2019c).
Sickle Cell Disease
Sickle cell disease, or β- thalassemia, is the final disorder that is identified by the heel-stick that will be discussed in this module. Sickle cell disease is a disease that affects the body’s hemoglobin structure leading to distorted, sickle-shaped red blood cells. The NIH and the US National Library of Medicine estimate that this condition affects 1 in 500 African American births in the US and between 1 in 1000 and 1 in 14000 Hispanic Americans. It is the most commonly inherited blood disease in the US. Sickle cell disease causes anemia as the malformed hemoglobin results in the affected patient’s red blood cells breaking down at a faster rate than normal. Infants with sickle cell disease may not show symptoms immediately, however children with this trait may exhibit a range of symptoms such as jaundice, shortness of breath, fatigue and even delayed growth. Long-term effects of sickle cell disease can range from mild to severe. Patients with sickle cell disease are at risk of developing clots due to the abnormal structure of their red blood cells. Side effects of these clots can include severe pain, organ failure, pulmonary hypertension, priapism (extended penile erection in the newborn), acute chest syndrome, or stroke (US National Library of Medicine, 2019). These are called vaso-occlusive crises, and they can be exacerbated by dehydration, pain, infection, or changes in the weather (Bender, 2017).
There is not a consistently effective cure for sickle cell disease at this time, but bone marrow transplants have been used with some success, curing several children of sickle cell disease before they acquired some of the chronic effects of the disease (Healthwise, 2019). At this time, further studies are needed to determine whether this intervention can be expanded to more patients in the sickle cell community as it does come with significant risks, including graft versus host disease and death. Until recently, the treatments for sickle cell disease have been aimed at controlling potential triggers for vaso-occlusive crises, such as aggressively managing infection and hydration needs, and aggressive pain management. It is important to note that despite the guidance that opioids are not an appropriate treatment for the chronic pain that some sickle cell patients may develop, vaso-occlusive crises are acute pain episodes and there is significant evidence to support the use of opioids during these periods. Blood transfusions and hydroxyurea (Hydrea, Droxia) are interventions available for the chronic management of sickle cell disease with the aim of preventing long-term effects. At this time, chronic transfusion is only recommended in children with sickle cell who have a transcranial Doppler reading of greater than 200 cm/sec or in patients who have a history of stroke. Hydroxyurea (Hydrea, Droxia) has been shown to decrease the number of vaso-occlusive pain crises per year in sickle cell patients, as well as reduce the need for blood transfusions to manage acute issues such as acute chest syndrome. However, it is not cleared by the FDA for use in children, and it has not been shown to significantly decrease the mortality rate in sickle cell disease (HHS, 2014).
Implications for Nursing
The nurse working with newborns diagnosed with sickle cell disease needs to be able to educate parents about what to look for in vaso-occlusive crises in the newborn or infant. Symptoms in the infant can include swelling in the hands or feet, or pain symptoms such as excessive crying. Parents need to be educated that their child will need regular follow-up with a specialist, which will include yearly transcranial Doppler measurements and other tests, and that their child may need more aggressive infection and fever management than other children. They will also need to be educated to ensure that their child stays hydrated and avoids physical exhaustion, high altitudes, and extreme temperatures. Patients with sickle cell disease and their parents should be encouraged that early identification of the disease with the appropriate education and management has been shown to reduce the rate of chronic complications of sickle cell disease (Bender, 2017). Resources available for parents of patients with sickle cell disease include the American Sickle Cell Anemia Association, the Sickle Cell Disease Association of America, the National Organization of Rare Disorders, and the Sickle Cell Information Center (US National Library of Medicine, 2019).
Critical Congenital Heart Disease
Critical congenital heart disease (CCHD) is a collection of structural abnormalities in the heart that can be present at birth. These defects can be identified by a lower than normal reading on the pulse oximetry portion of the newborn screening, which is completed at least 24 hours after birth (Centers for Disease Control and Prevention [CDC], 2019). The pulse oximetry portion of the newborn screening is considered normal if oxygen saturation levels are “≥95% in the right hand or foot with a ≤3% absolute difference between the right hand or foot” (CDC, 2018). The test is considered abnormal if any oxygen saturation level is below 90% or if oxygen saturation levels are below 95% in the right hand or foot for three tests which have been greater than an hour apart. The test is also considered abnormal if there is greater than a 3% difference between oxygen saturation measures of the right hand and foot on three separate occasions (CDC, 2018). CCHD is the most common type of birth defect as reported by the NIH (2019b), affecting as many as 18 in 10,000 births per year, and is responsible for at least 30% of all infant deaths secondary to birth defects. Infants who have CCHD may present with tachypnea, cyanosis, abnormal heartbeat, and low blood pressure. Undiagnosed CCHD can lead to sudden cardiac arrest, stroke, abnormal heart rhythms, heart failure, or premature death; however, due to early surgical intervention most patients with CCHD now survive infancy and can go on to lead normal lives (NIH, 2019b; US National Library of Medicine, 2019).
Implications for Nursing
The nurse working with newborns and infants should be aware that the pulse oximetry screening for CCHD is most effective when done at least 24 hours after birth. Thus, if a patient is to be discharged within 24 hours of birth, the screening should be done as late as possible or completed at a follow-up office visit. Nurses should also be aware that an abnormal, or failed reading on the pulse oximetry test does not necessarily indicate that an infant has CCHD, and the patient will need further testing and follow-up to determine diagnosis. Further testing for CCHD usually includes an echocardiogram after other causes of hypoxemia, such as respiratory obstruction, have been ruled out (CDC, 2018). Parents of children who have been diagnosed with CCHD should be counseled that with the proper interventional surgery, or series of surgeries, most patients go on to lead normal lives (CDC, 2019).
The NIH estimates that 1 to 3 in every 1,000 births in the US are affected by partial hearing loss or deafness (NIH, 2018). The hearing screen portion of the newborn screening is administered by either one or two tests. The two available tests are the automated auditory brainstem response (AABR) test and the otoacoustic emissions (OAE) test. The AABR test is comprised of a device that is placed over one ear at a time that emits a chirp. The device then measures brainstem responses to the stimuli (Hall, 2015). The OAE measures the eardrum’s responses to stimuli via waveform technology (CDC, 2014). There is some evidence to suggest that the usage of both tests for screening is associated with fewer false positives and that the screening should be completed more than 24 hours after birth to reduce the rate of false positives (Hall, 2015). One or both of these tests are mandatory for newborn screenings prior to discharge in 43 states as well as Puerto Rico and the District of Columbia. The remaining states require testing hearing at clinic visits shortly after birth (Gaffney, Eichwald, Gaffney, & Alam, 2014). Infants who fail the initial hearing test need to be referred to an audiologist for confirmatory testing and intervention (CDC, 2014). Prior to 1993, only infants considered to be high-risk for hearing loss were screened, resulting in nearly 50% of infants with hearing loss remaining undetected until they were old enough to demonstrate symptoms (NIH, 2018). Mandatory newborn hearing testing was instituted as a result of studies that showed that inter 2vention prior to six months of age was associated with higher verbal skills and more typical developmental patterns as well as a reduction in healthcare and special education spending as opposed to those who received intervention after six months of age (NIH, 2018). Early intervention for children with hearing loss is available in a variety of forms, including adaptive devices (hearing aids or cochlear implants), therapies and support groups (CDC, 2014).
Implications for Nursing
The nurse working with infants with an abnormal hearing screen should be aware that as of 2018, up to 50% of babies with a positive test are lost in follow up. It is important for the nurse and care team to educate parents about the benefits of early intervention for hearing loss as well as to provide the appropriate resources available in their area (NIH, 2018). Nurses working with children should also be aware that not all hearing loss is present at birth. If a child is exhibiting signs of hearing loss, they should be referred for testing, especially if the child was born outside of the United States or has not had their routine vaccinations, as several immunized diseases such as rubella can cause acquired hearing loss (Smith, Bale, & White, 2005).
General Implications for Nursing Regarding All Aspects of the Newborn Screen
As discussed, there is solid evidence that all aspects of the newborn screen are vital to the wellbeing and early intervention of the children identified. There is also wide-spread participation across the US in the newborn screening tests (NIH, 2018). This is partially due to the fact that participation is mandatory, meaning that hospitals are required to perform the test and that parental consent is not necessary. Most states allow for refusal based on religious beliefs, with the exception of Nebraska, which registers the refusal of participation as neglect (Tarini & Goldenberg, 2012). This allowance for refusal does present the risk of missed diagnosis, albeit in a very small subset of the population (Kelly, Makarem & Wasserstein, 2016). There is also rising concern among some parents regarding the practice of saving the dried blood from the newborn screen for further testing and research, such as the usage of these cards in genome sequencing (Tarini & Goldenberg, 2012). In all cases, parents should be educated that the only known risk associated with newborn screening is the risk of a false positive, while the risks associated with a missed diagnosis could be life-threatening (Kelly et al., 2016). Parents should also be made aware of the policies present at their facility regarding saving blood samples and should have the option to opt-out of the storage of their infant’s heel stick card if they desire. Make note that this is an evolving field of medical ethics, and the nurse working with infants who have had screening should be aware of both their state’s and facility’s policy regarding the storage of these tests in order to be able to discuss them with parents if the need arises. Storage banks of these tests in both Minnesota and Texas were destroyed in 2012 as a result of lawsuits (Tarini & Goldenberg, 2012).
An overarching concern regarding newborn screening is the lack of education for parents regarding this testing. Despite mandatory testing, there is not standardized mandatory education to accompany the testing (Tarini & Goldenberg, 2012). There are studies that show parents of infants expressed confusion and increased distress upon the receipt of abnormal test results as they could not remember ever having received education regarding the testing at all. Currently the American Academy of Pediatrics Task Force on Newborn Screening is working to correct this educational gap (Botkin et al., 2016). Tarini and Goldenberg (2012) report that there has been resistance to the idea of presenting parents with education regarding newborn screening prenatally due to the overwhelming amount of education parents receive at these visits. There is also concern that educating parents directly after birth is not the most effective measure as this can be a period of stress and fatigue for many parents (Tarini & Goldenberg, 2012). Parents in the 2009 study by Tluczek et al. report that they may have remembered the information if the importance of the test was stressed in person or verbally prenatally and reinforced after birth. In general, nurses should be aware that prenatal patients and parents of newborns would likely benefit from verbal reinforcement or further explanation of the test even if a pamphlet or brochure has been provided due to the vast amount of written materials given during these visits (Tluczek et al., 2009). Nurses should also be aware that there is evidence to support delivering newborn education in multiple forms of media and especially during prenatal visits (Botkin et al., 2016). Multiple studies show the need for improved education for parents surrounding newborn screening; however, as previously stated, national committees are still working on the standardization of this education (Botkin et al., 2016; Kelly et al., 2016).
The future of newborn screening stands to benefit from the relatively new ability to sequence the human genome (Tarini & Goldenberg, 2012). Due to science’s increasing ability to diagnose rare and life-threatening conditions early, new tests are often added to the panel of tests that are able to be performed at birth. The addition of these tests to the RUSP panel requires nomination by a multidisciplinary team and the approval by a condition review workgroup after a systematic, evidence-based review of the condition (Federal Advisory Committees, 2019). Nurses should be aware that the list of diseases included in the newborn screening are increasing all the time, and are already more comprehensive than the scope of this module.
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