The Term Infant with Problems: Early Jaundice

Jaundice is one of the most common problems that affect infants in the first week of life. Between 5 and 12% of breastfed infants had bilirubin levels > 15 mg/dL compared to 0.6 to 2% of infants who were fed formula ( Lascari, 1986 ).

Jaundice is caused by increased bilirubin levels. Bilirubin levels are a function of the amount of bilirubin that is produced by the infant and the amount excreted, so either producing more or excreting less will increase the bilirubin level. Breastfed infants get about 100 cc/day (3 oz) of colostrum in the first 1 to 3 days of life. Infants who are fed formula take between 6 and 12 oz. per day of formula in the same time period. The smaller intake of colostrum yields a smaller stool output in breastfed infants and thus less excretion of bilirubin. This results in higher bilirubin levels ( DeCarvalho, 1985 ).

Another determinate of stool output is the gastrocolic reflex. The more frequently an infant eats the more frequently he or she stools (gastrocolic reflex). DeCarvalho found that infants who were fed more than eleven times in 24 hours had a mean maximum bilirubin concentration of 6 mg/dL. Those who were fed between 5 and 6 times in 24 hours had a mean maximum bilirubin concentration of 10 mg/dL ( DeCarvalho, 1982 , DeCarvalho, 1985 ).

Bertini studied 2174 term Italian newborns to evaluate the effect of breastfeeding on the incidence of early jaundice. 74% of the infants were solely breastfed, 5% were fed only formula, and 22% were breastfed but supplemented with formula. Supplementation occurred by maternal request, for birthweight < 2500 gms, or due to weight loss of 4% at 24 hours of age, 8% at 48 hours of age and more than 10% after 72 hours of age. Sole breastfeeding was correlated with total serum bilirubin levels < 12.9 mg/dl. Infants supplemented with formula lost more weight and showed higher rates of total serum bilirubin levels (>12.9 mg/dL) compared to those infants solely breastfed and solely fed formula. The authors concluded that lack of intake in the first three to four days of life was associated with increased bilirubin levels. ( Bertini, 2001 ). Consequently hyperbilirubinemia may be a marker of breastfeeding difficulties in an infant in the first three to four days of life.

Kernicterus

Since the 1990's, a number of cases of kernicterus have been reported in breastfed infants who appeared healthy at discharge. A registry of 80 infants > 34 weeks gestation with kernicterus has been reviewed by Johnson and coworkers. Sixty-one (61) infants were readmitted to the hospital between 2.5 and 7 days of life. Sixty-six (66) of the 80 had severe neurologic sequelae. Fifty-nine (59) of 61 were breastfed, and all but one were born by vaginal delivery. Fourteen of the 61 had appointments within 3 days of discharge and were jaundiced on return visit but only 7 had a bilirubin level drawn. Three (3) of the 61 had an early follow-up appointment but did not keep the appointment. Forty-four of the 61 were given follow-up appointments at 1-2 weeks of age. On readmission, the following causes of hyperbilirubinemia were found: G6PD deficiency in 19 (31%), hemolysis in 10 (15%), bruising/cephalhematoma in 6 (10%), infection in 4 (6.6%), galactosemia or Crigler-Najjar syndrome in 3 (5%) with the remaining 19 (31%) being idiopathic or with a weight loss of > 10%. Although kernicterus is a very rare problem, its consequences are usually devastating for the baby and the family ( Johnson, 2002 ).

Three large hospital systems have evaluated the use of predischarge trancutaneous or serum bilirubin levels on the incidence of post-discharge severe hyperbilirubinemia (bilirubin levels of 20 to 25 mg/dL and > 25 mg/dL). All three studies found significant decreases in the incidence of severe hyperbilirubinemia after discharge. Two of the three studies also found an increase in the use of phototherapy for hyperbilirubemia. Kuzniewicz's study found that after implementation of universal screening, use of phototherapy according to AAP guidelines increased but there was also an increase in infants who received phototherapy below the recommended bilirubin levels (possibly unneeded). Reasons noted for the starting of phototherapy at lower than recommended bilirubin levels were: to prevent possible readmission, concern about inability to follow-up the infant, and rapid rate of rise in bilirubin levels. Whether this is appropriate use of phototherapy is unclear. So universal screening by serum or trancutaneous bilirubin levels prior to discharge is clearly associated with decreased rates of severe hyperbilirubinemia which may be a precursor to kernicterus if undedected and untreated, but is also associated with increased phototherapy use which may or may not be appropriate ( Eggert, 2006 , Mah, 2010 , Kuzniewicz, 2009 ).