Newborn Screening Nursing CE Course

Implications for Nursing

Nurses who interact with the parents of patients newly diagnosed with PKU need to be aware of the various resources available for these patients, as external support is vital in maintaining optimal health and wellness of chronically ill patients. The nurse should also be knowledgeable about 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, even though consistent medical management of the condition and adherence to a Phe-restricted diet has been shown to limit the negative effect on IQ tests and cognitive screens later in life. Resources for families of infants diagnosed with PKU include the NORD, Children's PKU Network, National PKU Alliance, and National PKU News (Hockenberry et al., 2019; NORD, 2019).

Congenital Hypothyroidism 

CH affects as many as 1 in 2,000 to 4,000 births annually in the US. It is one of the most common preventable causes of intellectual disability. This condition is caused by an underdeveloped, malfunctioning, or absent thyroid present at birth. In contrast to developed thyroid disease, which manifests later in life, the effects of CH manifest gradually over the first 6 weeks of life. This slight delay in symptom appearance after birth is due to the thyroxine hormone transfer from the pregnant individual. Treatment should start within the first 2 weeks of life to prevent developmental delay, making early detection essential for improved patient outcomes. CH affects phenotypically female infants twice as often as male infants for unknown reasons. Symptoms of CH include hypoactivity and somnolence, constipation, poor muscle tone, macroglossia (a thick, large tongue), swollen abdomen or outpouching of the umbilicus, and difficulty feeding. They may also exhibit large fontanelles, prolonged jaundice, and facial swelling (Bowden & Goldis, 2022; Endocrine Society, 2022; Weiner et al., 2020).

Just as in adults, CH is identified by testing for elevated levels of thyroid-stimulating hormone (TSH) in the blood, and as with PKU, this test is included in the 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 composed of total T4 and T3 resin uptake. CH is treated by medical supplementation of the thyroxine that the patient's thyroid is not producing. Infants who start treatment within the first 2 weeks of life will develop as expected. However, regular follow-up with an endocrinology provider is necessary to ensure that the patient's T4 and T3 stay within normal limits (ACMG, 2012b; Bowden & Goldis, 2022; Endocrine Society, 2022).

Implications for Nursing

The nurse working with infants diagnosed with CH should reassure parents that if their child is promptly treated, they will likely not have any permanent intellectual disability or developmental delay. Due to the time-sensitive nature of the treatment of CH, parents should be made aware of their infant's results and assisted in making an appointment with a pediatric endocrinology specialist as soon as possible to obtain confirmatory testing and receive treatment quickly. The nurse should educate parents that this disease will require lifelong medical management, and frequent follow-up visits will be necessary. Resources for parents of infants with CH include the American Thyroid Association and the MAGIC Foundation (ACMG, 2012b; Bowden & Goldis, 2022; Endocrine Society, 2022).

Cystic Fibrosis

CF is a genetic disorder that affects multiple body systems. CF is autosomal recessive and is caused by a mutated gene on the long arm of chromosome 7. This gene codes a protein of 1,480 amino acids called the cystic fibrosis transmembrane conductance regulator (CFTR). CF affects as many as 1 in 2,500 to 1 in 3,500 white newborns annually in the US. The disease is significantly less common in other populations, affecting only 1 in 9,200 Hispanic-American, 1 in 17,000 Black, and 1 in 35,000 Asian-American live births. This test is included in the RUSP (Hockenberry et al., 2019; NORD, 2017).

CF is characterized by abnormalities in the glands responsible for producing saliva, sweat, and mucus. The effect CF has on the mucus glands is especially problematic as this leads to the production of abnormally thick and sticky mucus in the digestive and respiratory tracts. This disease can lead to permanent lung damage with frequent infections and contributes to a shorter-than-average life expectancy. CF can also cause pancreatic insufficiency, cirrhosis, and malabsorption due to excess mucus within the gastrointestinal and hepatic systems. Symptoms of CF in an infant include salty skin, frequent cough, wheezing, meconium ileus, and failure to thrive. The standard diagnostic test for CF is a sweat test that measures the amount of salt in the newborn's sweat. In May 2005, the US Food and Drug Administration (FDA) approved the first blood test to detect CF. Most states perform immunoreactive trypsinogen (IRT) assays on a dried blood sample obtained using a heel stick. A positive newborn screen for CF requires several confirmatory follow-up tests with a specialist. Unfortunately, unlike PKU or CH, the effects of CF cannot be circumvented by early diagnosis and treatment at this time. However, early diagnosis and intervention are associated with a longer, better quality of life in individuals with the disease. Advances in the treatment available for CF, coupled with earlier identification and interventions, have increased the average life expectancy of an affected patient from the early teens to 40 years old (ACMG, 2012a; Hockenberry et al., 2019; NORD, 2017).

Implications for Nursing

The nurse working with newborns and infants should be aware that not all gene variations that can cause CF are included in the newborn screen in every state. If an infant presents with symptoms indicative of CF (e.g., frequent lung infections, digestive problems, failure to thrive, wheezing), they should still be referred for a follow-up sweat test or genetic testing. Nurses must educate patients and their families on healthy lifestyle changes, monitoring CF, and the importance of routine follow-up care. 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 (Hockenberry et al., 2019; National Heart, Lung, and Blood Institute [NHLBI], 2022a).

Sickle Cell Disease 

Sickle cell disease is an autosomal recessive genetic disorder that changes the body's hemoglobin structure from the normal hemoglobin A (HbA) molecule, with two alpha and two beta amino acid chains, to the abnormal hemoglobin S (HbS) molecule, composed of abnormal beta chains. When red blood cells (RBCs) consisting of many HbS molecules are exposed to an area of low oxygen, the abnormal beta chains contract, causing them to change into a distorted, sickle shape. The NIH and the US National Library of Medicine estimate that this condition affects 1 in 500 African Americans and between 1 in 1,000 to 14,000 Hispanics in the US. It is the most inherited blood disease in the US (NHLBI, 2022b).

The malformed hemoglobin in individuals with sickle cell disease causes the affected patient's RBCs to become fragile and break down faster than usual, resulting in anemia. Symptoms of sickle cell disease are varied and include jaundice, shortness of breath, fatigue, and delayed growth. Infants born with sickle cell disease may not show symptoms immediately. Long-term effects of sickle cell disease can range from mild to severe. Patient symptoms may also wax and wane with periods of extensive sickling leading to a crisis. The frequency of a crisis varies from every other week to annually. A crisis is often brought on due to hypoxemia. In addition, the rigid, sickle-shaped structure of the RBCs makes the cells sticky. This causes RBCs to clump together, blocking blood flow. This clumping puts patients with sickle cell disease at a higher risk of developing clots. Side effects of these clots can include severe pain, organ failure, pulmonary hypertension, priapism (extended penile erection), acute chest syndrome, or stroke, depending on the affected area. This disruption of blood flow is referred to as vaso-occlusive crises, which can be exacerbated by dehydration, pain, infection, or changes in the weather (Bender, 2021; Hockenberry et al., 2019; Ignatavicius et al., 2018).

A hematopoietic stem cell transplant (HSCT) is currently the only cure for sick cell disease. This procedure is only used for patients with severe sickle cell disease with complications such as stroke, recurrent pain crises, nephropathy, retinopathy, priapism, and osteonecrosis of multiple joints. HSCT is not available to all patients diagnosed with sickle cell disease as it comes with significant risks, including graft versus host disease and death. Until recently, the treatments for sickle cell disease had 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 experience, vaso-occlusive crises are acute pain episodes and there is significant evidence supporting the use of opioids during these periods. Blood transfusions and hydroxyurea (Hydrea, Droxia) are interventions available for chronic management of sickle cell disease to prevent long-term effects. At this time, regular transfusion is only recommended in children with sickle cell disease with a transcranial Doppler (ultrasound of intracranial cerebral circulation) reading of greater than 200 cm/sec or patients with stroke history. Hydroxyurea (Hydrea, Droxia) has been shown to decrease the number of vaso-occlusive pain crises per year in sickle cell patients and 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 has not been shown to decrease sickle cell mortality rate significantly. In 2019, the FDA approved voxelotor (Oxbryta) to treat sickle cell disease, but it is not available to children under 12 (Ashorobi & Bhatt, 2021; Hockenberry et al., 2019; Ignatavicius et al., 2018; NHLBI, 2022b).

Implications for Nursing

The nurse working with newborns diagnosed with sickle cell disease needs to be able to educate parents on the signs and symptoms of vaso-occlusive crises. Symptoms in the infant can include swelling in the hands or feet or nonverbal signs of pain such as excessive crying. Parents must be educated that their child will need regular, lifelong follow-ups with a specialist with annual transcranial Doppler measurements. Parents must understand that since their child has sickle cell disease, they may need more aggressive infection and fever management than other children. It is also essential that these children receive their regularly scheduled childhood vaccines to prevent illness. They will also need to be educated on the importance of their child staying hydrated and avoiding physical exhaustion, high altitudes, and extreme temperatures to prevent symptoms and complications. 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. 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 (Bender, 2021; Hockenberry et al., 2019; Ignatavicius et al., 2018).

Pulse Oximetry

Pulse oximetry screening (POS) in newborns is noninvasive and can be done at the bedside. It uses light to calculate the percentage of hemoglobin bound to oxygen within the blood. The pulse oximeter is placed onto the newborn (on the foot or hand), and the oxygen saturation of the blood is measured. Low oxygen saturation can be a sign of CCHD. The addition of POS into newborn testing is a new practice. States that have mandated this screening have reduced early infant cardiac deaths by 33% (Centers for Disease Control and Prevention [CDC], 2022; Dubay & Zach, 2022; Martin et al., 2020).

Critical Congenital Heart Disease

CCHD is a collection of structural abnormalities in the heart that can be present at birth. CCHD is the most common type of congenital disability, affecting as many as 18 in 10,000 births per year, and is responsible for at least 30% of all infant deaths secondary to congenital disabilities. The most common types of CCHD are bicuspid aortic valve (BAV), ventricular septal defects (VSDs), secundum atrial septal defects (ASDs), and tetralogy of Fallot. 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, with early surgical intervention, most patients with CCHD now survive infancy and lead typical lives (Martin et al., 2020).

Often these defects are diagnosed during pregnancy with a fetal echocardiogram; however, some heart defects are not identified until after birth. These defects can be identified by a lower-than-normal reading on the pulse oximetry portion of the newborn screening. The pulse oximetry portion of the newborn screening is considered normal if oxygen saturation levels are greater than 95% in the right hand or either foot with less than a 3% difference between the right hand or either foot. Measurements are not obtained from the left hand as the oxygenation of the left hand is not affected by the arterial duct. 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 administered more than an hour apart. The test is also considered abnormal if the difference in oxygen saturation between the right hand and foot is greater than 3% on three separate occasions. Other conditions that can cause a failed POS include hemoglobinopathy, hypothermia, infection, lung disease, persistent pulmonary hypertension, or a non-critical heart defect (CDC, 2022; Martin et al., 2020)

Implications for Nursing

The nurse working with newborns and infants should be aware that the POS for CCHD is most effective when done at least 24 hours after birth. Thus, if a patient is discharged within 24 hours of delivery, 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 POS does not necessarily indicate that an infant has CCHD. The patient will need further testing and follow-up to determine the cause of the low oxygen saturation. Additional testing for CCHD usually includes an echocardiogram after other causes of hypoxemia, such as respiratory obstruction, have been ruled out. Parents of children diagnosed with CCHD should be counseled that with the proper interventional surgery, or series of surgeries, most patients go on to lead typical lives (CDC, 2022).

Hearing Test

The hearing test portion of the newborn screening is administered as 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 uses a device placed over one ear at a time and emits a chirp. The device then measures brainstem responses to the stimuli. The OAE measures the eardrum's response to stimuli via waveform technology. There is evidence to suggest that the usage of both tests for screening is associated with fewer false positives (American Speech-Language-Hearing Association [ASHA], n.d.; Hockenberry et al., 2019)

Hearing Loss 

It is estimated that 1 to 3 in every 1,000 births in the US is affected by partial hearing loss or deafness. The permanent bilateral hearing loss rate in developed countries is 1.33 per 1,000 live births. Screening for hearing loss should be completed more than 24 hours after delivery to reduce the rate of false positives. The hearing test should be administered more than 48 hours after birth for infants born via cesarean section due to failures resulting from fluid remaining in the middle ear. One or both tests are mandatory for newborn screenings before discharge in 43 states, Puerto Rico, and the District of Columbia. The remaining states require that hearing is tested at a follow-up visit shortly after birth. Newborns who require transfer to the neonatal intensive care unit (NICU) should be screened once they are medically stable but before 1 month of age. Infants who fail the initial hearing test must be referred to an audiologist for confirmatory testing and intervention. Before 1993, only infants considered 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. Mandatory newborn hearing testing was instituted after studies showed that intervention before 6 months was associated with higher verbal skills and more typical developmental patterns. Research also showed a reduction in healthcare and special education spending compared to those who received a diagnosis and intervention after 6 months. Early intervention for children with hearing loss is available in various forms, including adaptive devices (hearing aids or cochlear implants), therapies, and support groups (ASHA, n.d.; Hockenberry et al., 2019; Korver et al., 2017).

Implications for Nursing

The nurse working with infants with an abnormal hearing screen should be aware that as of 2018, up to 50% of infants with a positive test are lost in follow-up. The nurse and care team must educate parents about the benefits of early intervention for hearing loss and provide the appropriate resources available in their area. Nurses working with children should also know 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 US or has not had their routine vaccinations, as several preventable diseases, such as rubella, can cause acquired hearing loss (ASHA, n.d.; Korver et al., 2017).

General Implications Regarding the Newborn Screen

There is solid evidence that all aspects of the newborn screen are vital for early diagnosis and intervention for children born with a congenital disease. There is also widespread participation across the US in the newborn screening process. This is partially due to laws requiring mandatory participation, meaning that hospitals are required to perform the newborn screen and that parental consent is unnecessary. Most states allow for refusal based on religious beliefs, except for Nebraska, which registers the refusal of participation as child neglect. This allowance for refusal does present the risk of missed diagnosis, albeit in a small subset of the population. Parents should be educated that the only known risk associated with newborn screening is a false positive test, while the risks associated with a missed diagnosis could be life-threatening. There is a rising concern among some parents regarding saving the dried blood from the newborn screen for further testing and research, such as genome sequencing. Parents should be made aware of the policies present at the 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. Note that this is an evolving field of medical ethics, and the nurse working with infants who have undergone screening should be aware of both their state's and facility's policies and procedures regarding the storage of these tests. As a result of lawsuits, storage banks in Minnesota and Texas were destroyed in 2012 (Dubay & Zach, 2022; Kelly et al., 2016; NEGC and Children's Hospital Boston, n.d.).

An overarching concern regarding newborn screening is the lack of education for parents. Despite mandatory testing, there is no standardized compulsory education. Parents should be educated on false-positive results, positive results, the cost of testing, and any special considerations, such as testing in a premature or critically ill newborn. Some studies show parents of infants expressed confusion and distress upon receiving abnormal test results as they could not remember ever having received education regarding the testing. The American Academy of Pediatrics Task Force on Newborn Screening is working to correct this educational gap. There has been resistance to presenting parents with education regarding newborn screening prenatally due to the overwhelming amount of education parents already 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. Parents report that they may have remembered the information if the importance of the test was stressed 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 testing, even if a pamphlet or brochure has been provided. Parents typically receive many written materials during prenatal visits. Nurses should also be aware of evidence to support delivering newborn education via multiple forms of media (Dubay & Zach, 2022; NEGC and Children's Hospital Boston, n.d.).

References

American College of Medical Genetics. (2012a). Newborn screening ACT sheet [elevated IRT +/- DNA] cystic fibrosis. https://www.acmg.net/PDFLibrary/Cystic-Fibrosis-ACT-Sheet.pdf

American College of Medical Genetics. (2012b). Newborn screening ACT sheet [elevated TSH (primary TSH Test)] congenital hypothyroidism. https://www.acmg.net/PDFLibrary/Primary-TSH-ACT-Sheet.pdf

American Speech-Language-Hearing Association. (n.d.). Newborn hearing screening. https://www.asha.org/practice-portal/professional-issues/newborn-hearing-screening/#collapse_4

Ashorobi, D., & Bhatt, R. (2021). Bone marrow transplantation in sickle cell disease. StatPearls [Internet]. https://www.ncbi.nlm.nih.gov/books/NBK538515/

Bender, M. A. (2021). Sickle cell disease. GeneReviews [Internet]. https://www.ncbi.nlm.nih.gov/books/NBK1377/

Bowden, S. A., & Goldis, M. (2022). Congenital hypothyroidism. StatPearls [Internet]. https://www.ncbi.nlm.nih.gov/books/NBK558913/

Centers for Disease Control and Prevention. (2022). Congenital heart defects information for healthcare providers. https://www.cdc.gov/ncbddd/heartdefects/hcp.html

Dubay, K. S., & Zach, T. L. (2022). Newborn screening. StatPearls [Internet]. https://www.ncbi.nlm.nih.gov/books/NBK558983/

Endocrine Society. (2022). Congenital hypothyroidism. https://www.endocrine.org/patient-engagement/endocrine-library/congenital-hypothyroidism

Hamilton, B. E., Martin, J. A., & Osterman, M. J. K., Division of Vital Statistics, National Center for Health Statistics. (2022). Births: Provisional data for 2021. Vital Statistics Rapid Release, 20. https://www.cdc.gov/nchs/data/vsrr/vsrr020.pdf

Health Resources & Services Administration. (2020). Recommended uniform screening panel. https://www.hrsa.gov/advisory-committees/heritable-disorders/rusp/index.html

Hockenberry, M. J., Wilson, D., & Rodgers, C. C. (2019). Wong's nursing care of infants and children (11th ed.). Elsevier.

Ignatavicius, D. D., Workman, M. L., Rebar, C. R., & Heimgartner, N. M. (2018). Medical-surgical nursing: Concepts for interprofessional collaborative care (9th ed.). Elsevier.

Kelly, N., Makarem, D. C., & Wasserstein, M. P. (2016). Screening of newborns for disorders with high benefit-risk ratios should be mandatory. The Journal of Law, Medicine & Ethics: A Journal of the American Society of Law, Medicine & Ethics, 44(2), 231–240. https://doi.org/10.1177/1073110516654133

Korver, A. M. H., Smith, R. J. H., Van Camp, G., Schleiss, M. R., Bitner-Glindzicz, M. A. K., Lustig, L. R., Usami, S., & Boudewyns, A. N. (2017). Congenital hearing loss. Nature Reviews Disease Primers, 3, 16094. https://doi.org/10.1038/nrdp.2016.94

Lowdermilk, D. L., Perry, S. E., Cashion, K., & Alden, K. R. (2016). Maternity & women's healthcare (11^th ed.). Elsevier.

Martin, G. R., Ewer, A. K., Gaviglio, A., Hom, L. A., Saarinen, A., Sontag, M., Burns, K. M., Kemper, A. R., & Oster, M. E. (2020). Updated strategies for pulse oximetry screening for critical congenital heart disease. Pediatrics, 146(1), e20191650. https://doi.org/10.1542/peds.2019-1650

National Heart, Lung, and Blood Institute. (2022a). Cystic fibrosis: Living with. https://www.nhlbi.nih.gov/health/cystic-fibrosis/living-with

National Heart, Lung, and Blood Institute. (2022b). Sickle cell disease: Treatment. https://www.nhlbi.nih.gov/health/sickle-cell-disease/treatment

National Institute of Child Health and Human Development. (2017). Newborn screening. https://www.nichd.nih.gov/health/topics/newborn

National Organization for Rare Disorders. (2017). Rare disease database: Cystic fibrosis. https://rarediseases.org/rare-diseases/phenylketonuria/

National Organization for Rare Disorders. (2019). Rare disease database: Phenylketonuria. https://rarediseases.org/rare-diseases/phenylketonuria/

New England Genetics Collaborative and Children's Hospital Boston. (n.d.). A guide for prenatal educators. https://www.babysfirsttest.org/sites/default/files/A%20guide%20for%20prenatal%20educators.pdf

Weiner, A., Oberfield, S., & Vuguin, P. (2020). The laboratory features of congenital hypothyroidism and approach to therapy. NeoReviews, 21(1), e37-e44. https://doi.org/10.1542/neo.21-1-e37