week 8

• Newborn Screening is a procedure to determine if the newborn infant has a heritable congenital metabolic disorder that may lead to serious physical health complications, mental retardation, and even death if left undetected and untreated
• Newborn Screening


  A procedure to determine if the newborn infant has a heritable congenital metabolic disorder that may lead to serious physical health complications, mental retardation, and even death if left undetected and untreated
• Newborn Screening initiated in the Philippines through PPS/ POGS "Philippine Newborn Screening Project" with 24 accredited Hospitals


  1996
• G6PD was added to the list of disorders and homocystinuria was deleted


  1998
• DOH included NBSP in the CHILD 2025 Program

  1999
• DOH created the National Technical Working Group for the nationwide implementation of NBSP

  2001
• NBS was integrated into the public health delivery system with the enactment of RA 9288 or "Newborn Screening Act of 2004 (6 Congenital Metabolic Disorders)

  2004
• Expanded newborn screening was implemented - 22 more disorders were added (hemoglobinopathies and additional metabolic disorders)


  2014

  
• Newborn Screening Act of 2004 (RA 9288)


  • Protect the rights of children to survival and full and healthy development as normal individuals
  • Provide for a comprehensive, integrative and sustainable national newborn screening system to ensure that every baby born in the Philippines is offered the opportunity to undergo newborn and be spared from heritable conditions
• Objectives of Newborn Screening

  • Newborn has access to newborn screening
  • Sustainable newborn screening system
  • All health practitioners are aware of the advantages
  • Parents recognize their responsibility

  
• Components of comprehensive NBS System

  • Education of relevant stakeholders
  • Collection and biochemical screening of blood samples taken from newborns
  • Tracking and confirmatory testing to ensure the accuracy of screening results
  • Drugs and medical/ surgical management and dietary supplementation to address the heritable conditions
  • Evaluation activities to assess long term outcome, patient compliance and quality assurance
• Ideal time for Newborn Screening

  • 48 hours to 72 hours after birth
  • May also be done 24 hours after birth
  • High risk newborn in NICU may be exempted from the 3-day requirement but must be tested by 7 days
• Blood Specimen Collection Procedure

  1. Heel prick method

  2. Blotted on a special absorbed filter card

  3. Blood is dried for 4 hrs. and sent to Newborn Screening Center
• NBS Screening Procedure


  1. Blood sample collection (>24 hours of life in term newborns)

  2. Analysis for the presence of the disorders screened (NIH laboratory)

  3. Negative

  4. Positive

  5. Confirmatory Test

  6. Positive

  7. Appropriate treatment and referrals

  8. No further testing
• Obligation of healthcare provider

  • Parents and practitioners have joint responsibility to ensure that NBS is performed
  • Refusal of testing on grounds of religious belief shall be written for documentation
• Newborn screening results


  • Seven (7) working days from the time the newborn screening samples are received parents should claim the results from their physician, nurse, midwife or health worker
  • Any laboratory result indicating an increased risk of a heritable disorder (e g. Positive screen) shall be immediately released, within twenty-four hrs. so that confirmatory testing can be immediately done
  • A positive screen means that the newborn must be referred at once to a specialist for confirmatory testing and further management

  
• Most common Newborn Screening Tests

  • Congenital hypothyroidism
  • Phenylketonuria
  • Galactosemia
• Congenital hypothyroidism


  • Can be either permanent or transient
  • Transient CH is associated with maternal Graves disease that was treated with antithyroid drugs
  • Most cases are nonhereditary and 15% of all cases are transmitted as an autosomal dominant trait
  • Most common is thyroid dysgenesis with unknown causes
• Congenital Hypothyroidism


  • Results from the absence or non functioning thyroid gland causing absence or lack of thyroxine needed for metabolism and growth of the body and the brain
  • The baby's physical growth suffer from irreversible mental retardation
• Common cause of Congenital Hypothyroidism

  • Iodine deficiency
  • Autoimmune antibodies that crossed the placenta
• Diagnostic Evaluation for Congenital Hypothyroidism

  • Neonatal screening - an initial filter paper blood spot thyroxine (T4) measurement followed by measurement of thyroid stimulating hormone (TSH) in specimens with low T4 values
  • Serum measurement of T4, triiodothyronine (T3), resin uptake, freeT4, and thyroid-bound globulin
  • Tests of thyroid gland function (Thyroid scan) usually involve oral administration of a radioactive isotope of iodine and measurement of iodine within 24 hours
  • Skeletal radiography is used to assess age
  • Thyroid function studies – levels of thyroid stimulating hormones in the blood, it is important to document the timing of the tests
• Assessment of Congenital Hypothyroidism


  • Enlarged tongue
  • Respiratory difficulties ( noisy respirations, airway obstruction)
  • Inadequate rapid eye movement (REM)
  • Suck poorly (sluggishness or choking)
  • Skin of the extremities feels cold, dry and scaly and does not perspire
  • Subnormal pulse, RR and body temperature
  • Prolonged Jaundice
  • Neck appears short and thick
  • Facial expression is dull and mouthed
  • Floppy, ragdoll appearance
• Therapeutic Management for Congenital Hypothyroidism

  • Lifelong thyroid hormone replacement therapy (as soon as possible after diagnosis)
  • Vitamin D supplemental to prevent the development of rickets
  • Provide parents with suggestions for long-term medication
• Therapeutic Management for Congenital Hypothyroidism

  • Drug of choice: Synthetic Levothyroxine (Synthroid, Proloid and Levothroid)
  • Optimum dosage - 0.5 and 2.0 mU/L during the first 3 years of life
  • If treatment started early - Normal physical growth and intelligence
• Nursing Care Management for Congenital Hypothyroidism

  • Early identification - initiation of treatment are essential because their delay will result in various degrees of cognitive impairment
  • Lifelong treatment – compliance with drug regimen (Levothroid and Synthroid)
  • Demonstrated symptoms - prolonged jaundice, constipation, and umbilical hernia should lead to a suspicion of hypothyroidism, which requires a referral to a pediatric endocrinologist
  • Unless there are maternal contraindicative factors, breastfeeding is acceptable and encouraged in infants with hypothyroidism
• Phenylketonuria


  An inborn error of metabolism inherited as an autosomal recessive trait (PAH gene chromosome 12q24) caused by a deficiency or absence of the enzyme needed to metabolize the essential amino acid phenylalanine hydroxylase
• Phenylketonuria


  Phenylalanine enzymes - controls the conversion of phenylalanine to tyrosine is deficient resulting in accumulation in the bloodstream and urinary excretion of abnormal amount causing brain damage and mental retardation
• Clinical manifestations in untreated PKU

  • Failure to thrive (growth failure)
  • Frequent vomiting
  • Irritability
  • Hyperactivity, unpredictable, erratic behavior
  • Older children display bizarre or schizoid behavior (fright reactions, screaming episodes, head hanging, arm biting, disorientation, failure to respond to strong stimuli, spasticity or catatonia-like positions
  • Cognitive impairment is thought to be caused by the accumulation of phenylalanine
• Diagnostic Evaluation for Phenylketonuria

  • Guthrie blood test - a bacterial inhibition assay for phenylalanine in the blood
  • Quantitative fluorometric assay and tandem mass spectrometry - only fresh heel blood, not cord blood, can be used for the test
• Therapeutic Management for Phenylketonuria


  • Restricting phenylalanine in the diet, low protein products
  • Dietary management: Nutritional need for optimum growth, Maintain phenylalanine levels within a safe range
  • Frequent monitoring of phenylalanine levels higher than 10 mg/dl - started on treatment to establish metabolic control as soon as possible, ideally by 7 to 10 days of age
  • Monitored blood and urine for phenylalanine levels
  • Hemoglobin levels to monitor presence of anemia
  • Diet must be supplemented with a specially prepared phenylalanine-free formula
• Galactosemia


  • A disorder of carbohydrate mechanism that is characterized by abnormal amounts of galactose in the blood (galactosemia) and in the urine (galactosuria)
  • Rare autosomal recessive disorder that results from various gene mutations leading to three distinct enzymatic deficiencies
• Enzymatic deficiencies in Galactosemia

  • GALT – galactose 1-phosphate uridyltransferase
  • GALK - galactokinase
  • GALE – galactose 4 - epimerase
• Galactosemia


  Inability to convert galactose to glucose accumulates in the blood, several organs are affected
• Effects of Galactosemia


  • Hepatic dysfunction leads to liver cirrhosis, resulting in jaundice by the second week of life
  • Spleen becomes enlarged as a result of portal hypertension
  • Cataracts recognizable by 1 or 2 months of age
  • Cerebral damage - symptoms of lethargy and hypotonia, mental retardation
  • Vomiting and diarrhea, leading to weight loss - ingesting milk which has a high lactose content
  • E. coli - sepsis is common presenting clinical sign
  • Death - first month of life is frequent in untreated infants
• Diagnostic Evaluation for Galactosemia


  • Infant's history, physical examination, galactosuria, increased levels of galactose in the blood, and decreased levels of GALT activity in erythrocytes
  • Infant may display characteristics of malnutrition, hypoglycemia, jaundice, hepatosplenomegaly, sepsis, cataracts, and decreased muscle tone
  • Newborn screening
  • Heterozygotes can be identified because of significantly lower levels of the essential enzyme
• Therapeutic Management for Galactosemia


  • Eliminating all milk and lactose containing formula, including breast milk
  • Feeding of choice - lactose-free formulas with soy-protein formula
  • Only foods low in galactose should be consumed. (fruits are high in galactose, and recommended to be avoided
  • Food lists should be given to the family to ensure that appropriate foods are chosen
  • If galactosemia is suspected - supportive treatment and care are implemented, monitoring for hypoglycemia, liver failure, bleeding disorders, and E. coli
• Galactosuria


  Increased levels of galactose in the blood
• GALT activity


  Decreased levels of GALT activity in erythrocytes
• Infant may display characteristics

  • Malnutrition
  • Hypoglycemia
  • Jaundice
  • Hepatosplenomegaly
  • Sepsis
  • Cataracts
  • Decreased muscle tone
• Newborn screening