neonatal jaundice

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Case 8
6-DAY-OLD WITH JAUNDICE - MEGHAN
Author: Mitchell A. Harris, M.D., Indiana University

Learning Objectives
1. Develop the knowledge and skills necessary to diagnose, manage, and refer
newborn infants presenting with jaundice, including:
Recognizing a newborn with jaundice
Understanding bilirubin physiology, including metabolism and toxicity
2. Compare and contrast the important findings and laboratory data helpful in
evaluating a newborn with jaundice with the following diagnoses:
Physiologic jaundice
Hemolytic (Rh or ABO incompatibility, red cell membrane or enzyme
defects, infection)
Hematomas and bruising
Breastfeeding-associated jaundice
Liver disease (biliary atresia, neonatal hepatitis)
Metabolic disease (hypothyroidism, hypoglycemia, galactosemia)
3. Identify treatment options for hyperbilirubinemia
4. Become familiar with the American Academy of Pediatrics’ practice guideline
"Management of Hyperbilirubinemia in the Healthy Term Newborn."
5. Complete a nutritional assessment of a breastfed infant.
6. Be familiar with nutritional advice related to breastfeeding, including the
advantages and common difficulties of breastfeeding.
Summary of clinical scenario: 6-day-old Meghan is jaundiced, but otherwise
appears healthy. The time frame of Meghan’s jaundice and total serum bilirubin
elevation > 15 mg/dL suggests the jaundice is not physiological. Although Meghan
has a positive family history of Mediterranean origin (suggesting the possibility of
glucose-6-phosphate dehydrogenase [G6PD] deficiency), a normal newborn
screen rules out metabolic disease and hypothyroidism. Normal CBC rules out
hemolytic disease. Meghan’s history of breastfeeding, normal physical exam, and
newborn screen—and the later appearance of jaundice—support a diagnosis of
breastfeeding-associated jaundice, which is treated by continued breastfeeding

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and observation.
Yellow skin
Direct Coombs test negative

Key Findings from History

Breastfeeding
Healthy
Father's Greek heritage

Key Findings from Physical
Exam

Jaundice
No cephalohematoma
Normal physical exam

Physiologic jaundice
Breast milk jaundice
Hemolysis

Differential Diagnosis

Metabolic
Sepsis
Biliary atresia
Liver disease

Key Findings from Testing

Final Diagnosis

Not applicable

Breastfeeding-associated
jaundice

Case highlights: Students review bilirubin metabolism and the causes and
consequences of hyperbilirubinemia in infants. Students learn how to estimate
bilirubin levels in an infant based on the extent of jaundice, why those with
glucose-6-phosphate dehydrogenase (G6PD) deficiency are at risk for jaundice,
and what role blood-type incompatibilities can play. Students learn how to treat
jaundiced infants. They also review the nutritional components of breast milk and
how to perform the Barlow and Ortolani maneuvers. Multimedia features include:
Instructional video on physical exam of a newborn, patient photos hyperlinked to
results of HEENT, chest, and abdominal exams.

Key Teaching Points
Knowledge
Jaundice: The physical finding associated with hyperbilirubinemia (either
unconjugated or conjugated form). The bilirubin accumulates in the epidermis,
resulting in yellow skin, sclera, and mucosae. Sixty percent of newborns have
sufficiently elevated bilirubin levels to become clinically jaundiced.

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Bilirubin production and metabolism:
75% of bilirubin production in newborns occurs when hemoglobin from red
blood cells is broken down and converted to unconjugated bilirubin.
The water-insoluble bilirubin binds to albumin and goes to the liver, where it
is conjugated with glucuronide by uridine diphosphate glucuronyltransferase
(UDPGT)
From there, the now-water-soluble bilirubin is excreted into bile.
o In adults, intestinal flora metabolize the conjugated bilirubin to
urobilinogen, then stercobilinogen, and it is excreted in the stool.
Neonates lack the gastrointestinal flora to metabolize the bile, so the
β-glucuronidase in the meconium hydrolyzes the conjugated bilirubin
back to an unconjugated form.
The unconjugated bilirubin is reabsorbed into the bloodstream, where
it binds to albumin and is recirculated (enterohepatic circulation).
An imbalance of bilirubin production and metabolism causes
hyperbilirubinemia.
Etiologies of indirect hyperbilirubinemia:
Physiologic jaundice:
Seen in full-term, healthy infants
Total bilirubin ≤ 15 mg/dL (≤ 257 mmol/L)
Treatment not required
Usually peaks at 3–4 days of life
May result from numerous factors, including:
Increased bilirubin production (from breakdown of the short-lived fetal
red cells)
Relative deficiency of hepatocyte proteins and UDPGT
Lack of intestinal flora to metabolize bile
High levels of β-glucuronidase in meconium
Minimal oral (enteral) intake in the first two to four days of life
resulting in slow excretion of meconium (especially common with
breastfed infants).
Jaundice associated with breastfeeding:
Breastfeeding jaundice:
Early in first week of life
Decreased milk supply leads to limited enteral intake
Increased enterohepatic circulation
Decreased gastrointestinal mobility promotes retention of meconium
Often difficult to distinguish from physiologic jaundice
Breast-milk jaundice:
Begins in first 4–7 days of life but may not peak until 10–14 days
Not the result of low milk volume
Cause not completely understood
May be caused by inhibitory substance in breast milk that increases

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enterohepatic circulation
Can persist for up to 12 weeks
Hemolysis:
Antibody-positive = Direct Coombs or direct antibody test (DAT) positive
Rh incompatibility (i.e., mother is Rh-negative and baby is
Rh-positive)
ABO incompatibility (i.e., mother is type O and baby is type A or B)
Incompatibilities with minor blood group antigens (much less
common)
Antibody-negative = Direct Coombs or DAT negative
Infants with red blood cell membrane defects (e.g., spherocytosisor
elliptocytosis) or enzyme defects (G6PD or pyruvate kinase
deficiency).
Non-hemolytic breakdown of red blood cells:
Extensive bruising from birth trauma
Large cephalohematoma or other hemorrhage (e.g., intracranial)
Polycythemia
Swallowed blood during delivery
Inborn metabolic disorders:
Crigler-Najjar syndrome: Decreased bilirubin clearance caused by
deficient or completely absent UDPGT
Galactosemia
Hypothyroidism
Ethnicity:
Neonatal jaundice is more common in Asian newborns than Caucasian
Less common in black infants than Caucasian
Glucose-6-phosphate dehydrogenase (G6PD) deficiency—an X-linked
recessive trait that can result in hemolysis and jaundice—is more common
in families of Mediterranean origin than in other ethnic groups.
Hemoglobinopathies, including sickle cell or one of the thalassemias, are
also more common among individuals from the Mediterranean region.
A family history of anemia or jaundice is important information.
Additional risk factors:
Prematurity
Bowel obstruction
Birth at high altitude
Kernicterus: Most serious outcome of unconjugated hyperbilirubinemia, but rare
in healthy term babies without hemolysis.

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Definition: Pathological term used to describe staining of the basal ganglia and
cranial nerve nuclei by bilirubin. Also describes the clinical condition that results
from the toxic effects of high levels of unconjugated bilirubin.
Etiology: In the past, kernicterus among full-term newborn infants primarily
resulted from Rh incompatibility (Erythroblastosis fetalis). Infants typically were
severely anemic, in shock, and acidotic, and had total bilirubin levels well above
25 mg/dL (428 µmol/L).
Signs of kernicterus in a seriously affected newborn:
Loss of suck reflex
Lethargy
Hyperirritability
Seizures
Possible death
Possible sequelae:
Opisthotonus (abnormal posturing that involves rigidity and severe arching
of the back, with the head thrown backward)
Rigidity
Oculomotor paralysis
Tremors
Hearing loss
Ataxia
Prevention:
Screening for Rh incompatibility and use of anti-Rh immunoglobulin
(RhoGAM®) have markedly reduced Rh-induced hemolysis and the
incidence of kernicterus.
Treatment of unconjugated hyperbilirubinemia with phototherapy also has
had an important impact.
Breastfeeding:
Breast milk content: Breast milk contains the perfect balance of carbohydrates,
fats, proteins for human infants, as well as antibodies, growth factors, and other
components:
Carbohydrates: Both human milk and standard infant formulas contain
lactose as the major carbohydrate. Lactose intolerance is uncommon in the
first year of life.
Fats: Represent approximately 50% of calories in human milk. Most of the
fat in breast milk appears at the end of feeding on each breast, so it is
important that infants empty each breast before going to the other.
Proteins: Combination of whey proteins (70%) and casein (30%).
Formulas contain slightly more protein than human milk. The casein:whey
ratio of cow-milk-based formulas varies. Unmodified cow milk contains

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approximately three times the protein content of human milk and
approximately 80% casein and 20% whey proteins. As mentioned, infants
should not be given cow's milk ("regular" milk from the dairy section) until
one year of age.
Colostrum: Yellowish fluid produced in the first five days postpartum, and
gradually replaced by milk. Concentrated source of non-nutritive substances
—oligosaccharides, lactoferrin, lysozyme, growth factors, bifidobacteria, and other
substances that protect against infection and promote growth.
Benefits of breastfeeding:
Infants:
Maternal-infant bonding
Protection against infections (e.g., otitis media, respiratory infections,
diarrhea)
Reduced rates of sudden infant death syndrome (SIDS)
Reduced rates of some allergic reactions
Maternal:
Decreased postpartum bleeding and more rapid uterine involution
Lactational amenorrhea and delayed resumption of ovulation (increased
child spacing)
Earlier return to pre-pregnant weight (compared with women who
formula-feed)
Improved bone remineralization postpartum with reduction in hip fractures
in the postmenopausal period
Decreased cost, relative to formula
Ready availability without preparation time
Common breastfeeding problems:
Enlarged, tender breasts (commonly caused by engorgement, mastitis,
plugged ducts [galactocele])
Improper latch, suckle
Prolonged feedings
Infants fall asleep before they finish feeding
Maternal inexperience/anxiety

Skills
History:
Normal newborn nutrition:
Breastfeeding infants nurse 8 to 12 times in 24 hours. Initially infants will
spend from 10–30 minutes per breast; later, 10–15 minutes each. Longer
feeds may indicate a problem.

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If a mother cannot breastfeed or chooses to not do so, she may feed her
infant with a formula made from cow's milk or soy protein isolate, with
assurance that the major nutrients will be provided by either. Infants
younger than 12 months should not be fed unmodified cow’s milk.
References:
Satter E. Child of Mine: Feeding With Love and Good Sense. Palo Alto, CA: Bull
Publishing Company, 2000; 100-101.
Beckman CRB, Ling FW, Laube DW, Smith RP, Barzansky BM, Herbert WNP.
Obstetrics and Gynecology, 4th Ed. Baltimore, Maryland: Lippincott Williams and
Wilkins, 2002; 157-159.
Normal newborn elimination:
Stools
By third day of life, bowel movements should start appearing yellow (no
longer meconium).
By sixth or seventh day, infant should have three to four stools/day (some
have stools with every feeding).
Voiding
By third day of life, infant should be voiding three to four times a day.
By the sixth day, infant should be voiding at least six times a day.
Urine should be pale yellow.
Physical exam:
Weight loss
Breastfed infants may lose up to 7–10% of their birth weight during first
four to five days. Should return to birth weight by two weeks of age.
If weight loss > 10% of birth weight—or birth weight not regained by two
weeks—need further assessment and intervention.
Be consistent when weighing infants (e.g., wet/dirty diapers and IV arm
boards can add significant amount of weight)
Head findings
Fontanelle: Initially anterior fontanelle may barely be open due to overriding
sutures. Within a few days, sutures separate. Average diameter of anterior
fontanelle 2.5–5.0 cm. In most full-term newborns the posterior fontanelle
is not palpable.
Caput succedaneum: Edematous swelling over the presenting portion of the
scalp of an infant. It overlies the periosteum and crosses suture lines.
Cephalohematoma: Subperiosteal hemorrhage. Does not extend across a
suture line.
Skin exam

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Bilirubin levels can be approximated using dermal zones—observing how far
the jaundice extends down the body.
Jaundice typically is first noticed on a newborn’s face at a bilirubin level of
approximately 4–5 mg/dL (68–86 µmol/L); it then progresses down the
trunk to the extremities (cephalocaudal progression) as the bilirubin level
rises.
In most infants, bilirubin level could be expected to be in the 10–15 mg/dL
(171–257 µmol/L) range when jaundice is visible below the knees.
However, these dermal zones simply refer to the area of the body where the
jaundice is visible and should be used only to estimate serum bilirubin
levels.
Whenever there is concern about hyperbilirubinemia, a serum total bilirubin
level should be obtained.
Chest
A term infant normally may have 0.5–1.0 cm of palpable breast tissue.
Unilateral/bilateral engorgement of the breasts can occur in both male and
female infants.
Distinguish from mastitis, in which breast has redness, warmth and
swelling.
Abdomen
Hepatosplenomegaly may be identified in certain conditions that cause
jaundice in the newborn (e.g., galactosemia, significant hemolytic disease).
Infants whose jaundice is caused by congenital infections such as
cytomegalovirus, toxoplasmosis, syphilis, rubella, or herpes may have
hepatosplenomegaly along with elevated direct and indirect bilirubin levels.
Hip exam
Need to screen for developmental dysplasia of the hip (DDH). Most
commonly found in:
Left hip (3:1)
Females
Breech presentation
Caucasians, Native Americans
Family history of DDH
The Barlow maneuver identifies dislocatable hips:
Examiner places thumb on region of lesser trochanter and middle
finger over greater trochanter.
With infant’s hips flexed to 90 degrees, hip is brought into adduction
and gentle downward pressure with the hand is applied to the hip.
A normal hip will not dislocate, while a dislocatable hip will subtly
move out of socket.
The Ortolani maneuver identifies dislocated hips:
Examiner places fingers over the greater trochanter and abducts
infant’s hip while pushing femoral head anteriorly.

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If hip is dislocated, maneuver will cause the femoral head to relocate
with a "clunk."

Differential diagnosis
More likely diagnoses
1. Physiologic jaundice in term newborn peaks at three to four days and
resolves by the fourth or fifth day of life. It is often very difficult to
distinguish breast-milk jaundice from physiologic jaundice.
2. Breastfeeding-associated jaundice may be caused either by an
inhibitory substance in the milk that increases enterohepatic circulation or
by a decreased milk supply, leading to a decreased enteral intake and
increased enterohepatic circulation.
3. Hypothyroidism: Untreated congenital hypothyroidism can cause
prolonged jaundice, lethargy, large fontanelles, macroglossia, umbilical
hernia, constipation, abdominal distention, and severe developmental
retardation. Will be detected on the newborn screen.
4. Cephalohematoma: Subperiosteal hemorrhage localized to the cranial
bone that was traumatized during delivery. Swelling does not extend across
a suture line. Blood reabsorbed from the cephalhematoma will contribute to
hyperbilirubinemia. (In contrast, caput succedaneum is an edematous
swelling overlying the periosteum and crossing suture lines. The swelling
consists of serum and would not cause hyperbilirubinemia.)
5. Bruising: Bruising from birth trauma or any other bleeding can also lead to
increased bilirubin production as blood extravasated into tissues will be
broken down and converted to bilirubin.
6. Sepsis: Septic infants may have jaundice (with elevated total and direct
bilirubin) as one sign of serious infection, along with other clinical
manifestations such as temperature instability, respiratory distress, apnea,
irritability, lethargy, poor tone, vomiting, or poor feeding. When jaundice is
the only clinical finding, however, sepsis is highly unlikely as the cause of
the increased bilirubin levels. Breastfeeding offers some protection against
infection.
Less likely diagnoses:
Hemolysis: Hemolytic disease would be expected to cause more severe jaundice
at an earlier age. Severe hemolytic disease can cause visible jaundice in the first
24 hours of life.
Metabolic disorders such as galactosemia or urea cycle defects usually have
signs and symptoms including: lethargy, vomiting, seizures, hypotonia, diarrhea,
poor feeding, ascites, and hepatomegaly. Many are ruled out by a normal
newborn screen.
Biliary atresia: Typically presents later, between three and six weeks of age,
with progressive jaundice, dark urine, acholic stools. Causes a direct

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hyperbilirubinemia. Must be evaluated with fractionated (total and direct)
bilirubin. If biliary atresia is suspected, infant will be referred to a pediatric
gastroenterologist or surgeon. When diagnosed early, it can be treated with a
surgical procedure called the Kasai procedure, which restores bile flow and
prevents liver damage.
Liver disease: Intrinsic liver disease is a very rare cause of neonatal jaundice:
Gilbert’s syndrome (reduced activity of the enzyme glucuronyltransferase) is
a relatively common cause of harmless jaundice (seen in approximately 5%
of the population).
Crigler-Najjar syndrome (absence or low levels of UDPGT) can cause severe
(type I) or mild (type 2) jaundice.

Studies
Evaluation of jaundice in a newborn:
Total serum bilirubin (TSB)
Indicated in all infants with jaundice in the first 24 hours of life or with
significant jaundice
TSB > 15 mg/dL suggests jaundice that is not physiological
Direct bilirubin
Indicated if infant is ill or has:
Light stools or dark urine
Persistent jaundice (> 3 weeks)
Complete blood count (CBC)
To evaluate for hemolytic disease or anemia
If anemia is found, an elevated reticulocyte count would be further evidence
of hemolysis.
Blood smear
Useful in diagnosing ABO hemolytic disease (will see schistocytes or
microspherocytes)
More essential if jaundice presents in first 24 hours
Newborn screen
To evaluate for metabolic disease

Management
Hyperbilirubinemia:

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Evaluate risk factors for severe hyperbilirubinemia in infants > 35 weeks’
gestation:
Major risk factors:
Pre-discharge total serum bilirubin (TSB) or total conjugated bilirubin (TcB)
level in the high-risk zone
Jaundice observed in first 24 hours of life
Blood group incompatibility, with positive direct antiglobulin test
Gestational age 35–36 week
Previous sibling received phototherapy
Cephalohematoma or significant bruising
Exclusive breastfeeding, particularly if nursing is not going well and weight
loss is excessive
East Asian race
Minor risk factors:
Pre-discharge TSB or TcB level in high intermediate-risk zone
Gestational age 37–38 week
Jaundice observed before discharge
Previous sibling with jaundice
Macrosomic infant of a diabetic mother
Maternal age > 25 years
Male gender
Decreased risk:
TSB or TcB level in the low-risk zone
Gestational age 41 week
Exclusive bottle feeding
Black race
Discharge from hospital after 72 hours
Treatment: Treatment of jaundice in a newborn is based on assessment of risk
factors, the level of serum bilirubin, and family and physician preference:
Phototherapy: An effective means of lowering bilirubin. The Bhutani nomogram
can be used to determine when to implement (based on age and risk factors).
Temporary formula feeding: If serum bilirubin is 16–25 mg/dL, many
pediatricians may decide to substitute breastfeeding with formula for 24–48 hours
and then resume breastfeeding.
Newborn nutritional supplements
Iron: After age six months, all infants need a reliable source of iron. While the
iron in breast milk is highly bioavailable, the total amount cannot support
adequate hemoglobin production.

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Infants who have been exclusively breastfed should be should be started on
iron-enriched foods, such as fortified cereals and meats, at six months.
Most standard formulas are iron-fortified.
Iron supplements may be needed during the first six months if the baby is
anemic or has low iron stores (e.g., as in premature infants).
Fluoride: Breastfed and bottle-fed infants both should receive fluoride
supplements after six months of age if the water supply lacks fluoride (< 0.3
ppm).
Vitamin D: Exclusively breastfed infants may need vitamin D supplementation in
the first six months. Supplementation with 400 IU of vitamin D should be initiated
within days of birth for all breastfed infants. (Infants who are not breastfed should
also receive supplementation with 400 IU of vitamin D if they do not ingest at
least 1 L of vitamin D-fortified formula daily.)
Rickets can occur in strictly breastfed infants (generally appears between six
and 24 months and responds to treatment with vitamin D).
Breast engorgement from breastfeeding:
Instruct mother to apply warm compresses before breastfeeding and cold
compresses between feedings to relieve the discomfort.
Use manual or mechanical expression of the areola to relieve fullness and
facilitate latching-on.
Have baby nurse frequently to relieve breast engorgement.

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