Newborn Screening

Newborn Screening is a topic covered in the Davis's Lab & Diagnostic Tests.

To view the entire topic, please or .

Nursing Central is an award-winning, complete mobile solution for nurses and students. Look up information on diseases, tests, and procedures; then consult the database with 5,000+ drugs or refer to 65,000+ dictionary terms. Explore these free sample topics:

-- The first section of this topic is shown below --

Synonym/Acronym:

NBS, newborn metabolic screening, tests for inborn errors of metabolism, early hearing loss detection and intervention for newborns.

Rationale

To evaluate newborns for congenital abnormalities, which may include hearing loss; presence of heart defects; identification of hemoglobin variants such as thalassemias and sickle cell anemia; presence of antibodies that would indicate an HIV infection; or metabolic disorders such as homocystinuria, maple syrup urine disease (MSUD), phenylketonuria (PKU), tyrosinuria, and unexplained physical or intellectual disabilities.

Patient Preparation

There are no food, fluid, activity, or medication restrictions unless by medical direction.

Normal Findings

Method: Thyroxine, thyroid-stimulating hormone (TSH), and HIV—immunoassay; amino acids—tandem mass spectrometry; hemoglobin variants—electrophoresis.

Screening components may vary by state, but the core test program consists of hearing, heart, and blood screening tests. The age for screening is within 72 hr of birth (Neonates—3 days).


Hearing Screen
Hearing Test
AgeNormal Findings
Neonates–3 daysNormal pure tone average of –10 to 15 dB

Heart Function Screen
Heart Screen for Critical Congenital Heart Defects
AgeNormal Findings
Neonates–3 daysPulse Oximetry Test = Pass, Negative, or In Range

Blood Screen
Endocrine DisordersNormal Findings
TSH for Primary Congenital HypothyroidismLess than 20 micro-international units/mL
Thyroxine, Total (Total T4) for Primary Congenital Hypothyroidism5.4–22.6 mcg/dL
17–hydroxyprogesterone (17–OHP) for Congenital Adrenal HyperplasiaLess than 15.1 ng/mL
Hemoglobin Disorders
Sickle Cell Anemia (Hgb SS), Beta-thalassemia (Hgb SbetaTh), SC disease (Hgb SC) for Abnormal HemoglobinsNegative for abnormal hemoglobins
Disorders of Amino Acid Metabolism
Blood spot analysisNormal findings. Numerous amino acids are evaluated by blood spot testing, and values vary by method and laboratory. The testing laboratory should be consulted for corresponding reference ranges.
Disorders of Organic Acid Metabolism
Blood spot analysisNormal findings. Numerous organic acids are evaluated by blood spot testing, and values vary by method and laboratory. The testing laboratory should be consulted for corresponding reference ranges.
Disorders of Fatty Acid Oxidation
Blood spot analysisNormal findings. Numerous fatty acids are evaluated by blood spot testing, and values vary by method and laboratory. The testing laboratory should be consulted for corresponding reference ranges.
Infectious Disease Testing
HIV antibodiesNegative
Abnormal screening results are followed up with specific diagnostic testing.

Critical Findings and Potential Interventions

N/A

-- To view the remaining sections of this topic, please or --

Synonym/Acronym:

NBS, newborn metabolic screening, tests for inborn errors of metabolism, early hearing loss detection and intervention for newborns.

Rationale

To evaluate newborns for congenital abnormalities, which may include hearing loss; presence of heart defects; identification of hemoglobin variants such as thalassemias and sickle cell anemia; presence of antibodies that would indicate an HIV infection; or metabolic disorders such as homocystinuria, maple syrup urine disease (MSUD), phenylketonuria (PKU), tyrosinuria, and unexplained physical or intellectual disabilities.

Patient Preparation

There are no food, fluid, activity, or medication restrictions unless by medical direction.

Normal Findings

Method: Thyroxine, thyroid-stimulating hormone (TSH), and HIV—immunoassay; amino acids—tandem mass spectrometry; hemoglobin variants—electrophoresis.

Screening components may vary by state, but the core test program consists of hearing, heart, and blood screening tests. The age for screening is within 72 hr of birth (Neonates—3 days).


Hearing Screen
Hearing Test
AgeNormal Findings
Neonates–3 daysNormal pure tone average of –10 to 15 dB

Heart Function Screen
Heart Screen for Critical Congenital Heart Defects
AgeNormal Findings
Neonates–3 daysPulse Oximetry Test = Pass, Negative, or In Range

Blood Screen
Endocrine DisordersNormal Findings
TSH for Primary Congenital HypothyroidismLess than 20 micro-international units/mL
Thyroxine, Total (Total T4) for Primary Congenital Hypothyroidism5.4–22.6 mcg/dL
17–hydroxyprogesterone (17–OHP) for Congenital Adrenal HyperplasiaLess than 15.1 ng/mL
Hemoglobin Disorders
Sickle Cell Anemia (Hgb SS), Beta-thalassemia (Hgb SbetaTh), SC disease (Hgb SC) for Abnormal HemoglobinsNegative for abnormal hemoglobins
Disorders of Amino Acid Metabolism
Blood spot analysisNormal findings. Numerous amino acids are evaluated by blood spot testing, and values vary by method and laboratory. The testing laboratory should be consulted for corresponding reference ranges.
Disorders of Organic Acid Metabolism
Blood spot analysisNormal findings. Numerous organic acids are evaluated by blood spot testing, and values vary by method and laboratory. The testing laboratory should be consulted for corresponding reference ranges.
Disorders of Fatty Acid Oxidation
Blood spot analysisNormal findings. Numerous fatty acids are evaluated by blood spot testing, and values vary by method and laboratory. The testing laboratory should be consulted for corresponding reference ranges.
Infectious Disease Testing
HIV antibodiesNegative
Abnormal screening results are followed up with specific diagnostic testing.

Critical Findings and Potential Interventions

N/A

There's more to see -- the rest of this topic is available only to subscribers.