Flashcards in Case 8 Deck (76)
What does a history of breastfeeding, normal physical exam, normal newborn screen and later appearance of jaundice suggest?
A diagnosis of breastfeeding-associated jaundice. This is treated with continued breastfeeding and observation.
What is the differential diagnosis for breastfeeding-associated jaundice?
Physiologic jaundice, breast milk jaundice, hemolysis, metabolic, sepsis, biliary atresia, liver disease
What is jaundice?
The physical finding associated with hyperbilirubinemia (either unconjugated or conjugated form). The bilirubin accumulates in the epidermis, resulting in yellow skin, sclera and mucosal. Sixty percent of newborns have sufficiently elevated bilirubin levels to become clinically jaundiced.
75 percent of bilirubin production in newborns occurs when...
...hemoglobin from red blood cells is broken down and converted to unconjugated bilirubin.
How is water-insoluble bilirubin processed in the adult?
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. In adults, intestinal flora metabolize the conjugated bilirubin to urobilinogen, then stercobilinogen and it is excreted in the stool.
What happens to bile in neonates?
Neonates lack the GI flora to metabolize bile, so the beta-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.
What are the etiologies of indirect hyperbilirubinemia?
Physiologic jaundice, Jaundice associated with breastfeeding, Hemolysis, Non-hemolytic breakdown of red blood cells, Inborn metabolic disorders.
What is physiologic jaundice?
Seen in full-term, healthy infants. Total bilirubin is less than or equal to 15 mg/dL (less than or equal to 257 mmol/L). Treatment is not required. Usually peaks at 3-4 days of life.
What factors may lead to physiologic jaundice?
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 beta-glucuronidase in meconium, minimal oral (enteral) intake in the first two to four days of life resulting in slow excretion of meconium (esp. common with breastfed infants).
What is breastfeeding jaundice?
Early in first week of life. Decreased milk supply leads to limited enteral intake. Increased enterohepatic circulation. Decreased GI motility promotes retention of meconium. Often difficult to distinguish from physiologic jaundice.
What is 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 enterohepatic circulation. Can persist for up to 12 weeks.
What is Antibody positive hemolysis?
Direct Coombs or direct antibody test (DAT) positive.
-Rh incompatibility (i.e. mother is Rh neg and baby is Rh pos)
-ABO incompatibility (i.e. mother is type O and baby is type A or B)
-Incompatibilities with minor blood group antigens (much less common)
What is antibody negative hemolysis?
Direct Coombs or DAT negative. Infants with red blood cell membrane defects (eg. spherocytosisor elliptocytosis) or enzyme defects (G6PD or pyruvate kinase deficiency)
What non-hemolytic breakdown of red blood cells can cause jaundice?
Extensive bruising from birth trauma, large cephalohematoma or other hemorrhage (e.g. intracranial), Polycythemia, Swallowed blood during delivery.
What are inborn metabolic disorders that can cause jaundice?
Crigler-Najjar Syndrome, Galactosemia, Hypothyroidism.
What is Crigler-Najjar Syndrome?
Decreased bilirubin clearance caused by deficient or completely absent UDPGT.
How does ethnicity affect jaundice?
-Neonatal jaundice is more common in asian newborns than caucasian
-Less common in black infants than caucasian
-G6PD deficiency - an Xlinked 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.
What are additional risk factors for jaundice?
Prematurity, Bowel obstruction, Birth at high altitude
What is Kernicterus?
Most serious outcome of unconjugated hyperbilirubinemia, but rare in healthy term babies without hemolysis.
How do you define Kernicterus?
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.
What is the etiology of Kernicterus?
In the past, kernicterus among full-term newborn infants primarily resulted from Rh incompatibility (erythroblastosis fettles). Infants typically were severely anemic, in shock, and acidotic, and had total bilirubin levels well above 25 mg/dL (428 umol/L)
What are signs of kernicterus in a seriously affected newborn?
Loss of suck reflex, lethargy, hyperirritability, seizures, possible death.
What are possible sequelae of kernicterus?
Opisthotonus (abnormal posturing that involves rigidity and severe arching of the back, with the head thrown backward), rigidity, oculomotor paralysis, tremors, hearing loss, ataxia.
How do you PREVENT kernicterus?
-Screening for Rh incompatibility and use of anti-Rh immunoglobulin (RhoGAM) have markedly reduced Rh-induced hemolysis and the incidence of kernicterus.
-Tx of unconjugated hyperbilirubinemia with phototherapy also has had an important impact.
Breast milk content:
Breast milk contains the perfect balance of carbs, fats, proteins for human infants, as well as antibodies, growth factors, and other components.
Both human milk and standard infant formulas contain lactose as the major carbohydrate. Lactose intolerance is uncommon in the first year of life.
Represent approx. 50 percent 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.
Combination of whey proteins (70 percent) and casein (30 percent). Formulas contain slightly more protein than human milk. The casein::whey ratio of cow-milk-based formulas varies. Unmodified cow milk contains approx. 3 times the protein content of human milk and approx. 80 percent casein and 20 percent whey proteins. As mentioned, infants should not be given cow's milk ("regular" milk from the dairy section) until one year of age.
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.
What are the benefits of breastfeeding for the infant?
Maternal-infant bonding, Protection against infections (eg otitis media, respiratory infections, diarrhea), Reduced rates of sudden infant death syndrome (SIDS), Reduced rates of some allergic reactions.
What are the maternal benefits of breastfeeding?
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.
What are 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.
How often do breastfeeding infants nurse?
8 to 12 times in 24 hours. Initially infants will spend from 10-30 min per breast, later 10-15 min each. Longer feeds may indicate a problem.
What if a mother cannot breastfeed or chooses not to 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.
What is normal newborn stooling?
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).
What is normal newborn 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.
Infant Weight Loss:
-Breastfed infants may lose up to 7-10 percent of their birth weight during first four to five days. Should return to birth weight by two weeks of age.
-If weight loss is greater than 10 percent of birth weight - or birth weight not regained by two weeks - need further assessment and intervention
-Be consistent when weighing infants (eg wet/dirty diapers and IV arm boards can add signifiant amount of weight)
Fontanelle findings in an infant:
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.
What is caput succedaneum?
Edematous swelling over the presenting portion of the scalp of an infant. It overlies the periosteum and crosses suture lines.
What is Cephalohematoma?
Subperiosteal hemorrhage. Does not extend across a suture line.
What about the skin exam can be used to approximate bilirubin levels?
Bilirubin levels can be approximated using dermal zones - observing how far the jaundice extends down the body.
What is the bilirubin level at the face?
Jaundice is typically first noticed on a newborn's face at a bilirubin level of approximately 4-5 mg/dL (68-86 umol/L); it then progresses down the trunk to the extremities (cephalocaudal progression) as the bilirubin level rises.
What is the bilirubin level in an infant where jaundice reaches the knees?
In most infants, bilirubin level could be expected to be in the 10-15 mg/dL (171-257 umol/L) range when jaundice is visible below the knees.
What are dermal zones useful for? What should be used for an accurate read?
-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.
What is significant about a newborns chest on physical exam?
-A term infant normally has 0.5-1 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
When will infants with jaundice have hepatosplenomegaly?
-Hepatosplenomegaly may be identified in certain conditions that cause jaundice in the newborn (eg, galactosemia, significant hemolytic disease).
-Infants whose jaundice is caused by congenital infections such as CMV, toxoplasmosis, syphilis, rubella, or herpes may have hepatosplenomegaly along with elevated direct and indirect bilirubin levels.
In what is developmental dysplasia of the hip most commonly found:
-Left hip (3:1)
-Caucasians, Native Americans
-Family history of DDH
How do you complete the Barlow maneuver?
-Place 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.
How do you complete the Ortolani maneuver?
-Examiner places fingers over the greater trochanter and abducts infant's hip while pushing femoral head anteriorly
-If hip is dislocated, maneuver will cause the femoral head to relocate with a "clunk"
What are the most likely diagnosis in an infant with jaundice?
Physiologic jaundice, Breastfeeding-associated jaundice, hypothyroidism, cephalohematoma, bruising, sepsis.
What are less likely diagnosis in an infant with jaundice?
Hemolysis, Metabolic disorders, Biliary atresia, Liver disease
What is physiologic jaundice?
In term newborn peaks at 3-4 days and resolves by the 4th or 5th day of life. It is often very difficult to distinguish breast-milk jaundice from physiologic jaundice.
What is 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.
What is 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.
What is a 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 line. The swelling consists of serum and would not cause hyperbilirubinemia.)
What is bruising?
Bruising from birth trauma or any other bleeding can also lead to increased bilirubin production as blood extravasated into tissue will be broken down and converted to bilirubin.
What is 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.
What is 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.
What about metabolic disorders?
Such as galactosemia or urea cycle defects usually have signs and symptoms including: lethargy, vomiting, seizures, hypotonia, diarrhea, poor feeding, ascites, and hepatosplenomegaly. Many are ruled out by a normal newborn screen.
What about biliary atresia?
Typically presents later, between three and six weeks of age, with progressive jaundice, dark urine, acholic stools. Causes direct hyper bilirubinemia. Must be eval. with fractionated (total and direct) bilirubin. If biliary atresia is suspected, infant will be referred to a pediatrics gastroenterologist or surgeon. When dx early, it can be teated with a surgical procedure called the Kasai procedure, which restores bile flow and prevents liver damage.
What about liver disease?
Intrinsic liver dz 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 percent of the pop)
-Crigler-Najjar syndrome (absence or low levels of UDPGT) can cause severe (type 1) or mild (type 2) jaundice.
Total serum bilirubin (TSB):
-Indicated in all infants with jaundice in the first 24 hours of life or with significant jaundice.
-TSB greater than 15 mg/dL suggests jaundice that is not physiological
Indicated if infant is ill or has:
-Light stools or dark urine
-Persistent jaundice (greater than 3 weeks)
Complete blood count:
-To evaluate for hemolytic disease or anemia
-If anemia is found, an elevated reticulocyte could would be further evidence of hemolysis
-Useful in diagnosing ABO hemolytic disease (will see schistocytes or microspherocytes)
-More essential if jaundice presents in first 24 hours
What are the MAJOR risk factors for severe hyperbilirubinemia in infants greater than 35 weeks gestation?
-Pre-discharge total serum bilirubin (TSB) or total conjugated bilirubin (TcB) level in the high-risk zone
-Jaundice observed in first 24 hrs of life
-Blood group incompatibility, with positive direct anti globulin test
-Gestational age 35-36 weeks
-Prev. sibling received phototherapy
-Cephalohematoma or significant bruising
-Exclusive breastfeeding, particularly if nursing is not going well and wt. loss is excessive
-East asian race
What are MINOR risk factors for severe hyperbilirubinemia in infants greater than 35 weeks gestation?
-Predischarge TSB or TcB level in high intermediate risk zone
-Gestation age 37-38 weeks
-Jaundice observed before discharge
-Prev. sibling with jaundice
-Macrosomic infant of a diabetic mother
-Maternal age greater than 25 years
What factors decrease risk for severe hyperbilirubinemia in infants greater than 35 weeks gestation?
-TSB or TcB level in the low risk zone
-Gestation age 41 weeks
-Exclusive bottle feeding
-Discharge from hospital after 72 hours
What is treatment of jaundice based on?
Based on assessment of risk factors, the level of serum bilirubin, and family and physician preference.
What are the two main treatments for jaundice?
Phototherapy and Temporary formula feeding
An effective means of lowering bilirubin. The Bhutan 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.
After 6 mo, all infants need a reliable source of iron. While iron in breast milk is highly bioavailable, the total amount cannot support adequate hemoglobin production.
-Infants who have been exclusively breastfed 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 6 months if the baby is anemic or has low iron stores (eg, as in premature infants)
Breastfed and bottle fed infants both should receive fluoride supplements after six months of age if the water supply lacks fluoride (less than 0.3 ppm)
Exclusively breastfed infants may need vitaD supplementation in the first 6 mo. Supplementation with 400 IU of vitaD 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 the 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)