Ten pearls (and pitfalls) in the management of the jaundiced newborn: Remember to take a history. Ask about jaundice in previous siblings and check family ethnicity. Don't ignore jaundice in the first 24 hours--it is considered pathologic until proven otherwise. Some normal infants may appear jaundiced and have a bilirubin level of 5 mg/dL at 23 hours and 59 minutes. On the other hand, a bilirubin level of 5 mg/dL at 10 hours is almost certainly pathologic. Use your judgment. Don't treat 35 to 37 week gestation infants as if they were full-term infants. Although these babies are cared for in well-baby nurseries and are generally treated like full-term infants, they are not full term. They are not as vigorous and do not nurse as well as full-term infants. Infants at 37 weeks gestation are four times more likely to have a serum bilirubin level greater than 13 mg/dL than those at 40 weeks gestation. Don't send 35-week gestation infants home before 48 hours. Document your assessment, particularly if the infant is being discharged early. Document the presence or absence of jaundice and its severity. A late rising bilirubin is typical of G6PD deficiency. Think about the ethnic background: G6PD deficiency is much more likely to occur in families from Greece, Turkey, Sardinia, and Nigeria, and particularly in Sephardic Jews from Iraq, Iran, Syria, and Kurdistan. Your practice may not contain many such families but remember in today's world of travel and intermarriage, etc, these genes are ubiquitous and the diagnosis of G6PD deficiency should always be considered in a newborn child with a significant elevation of bilirubin, particularly if it is a male and the rise in bilirubin is of late onset. Don't use homeopathic doses of phototherapy. As with any drug, phototherapy should be provided in a therapeutic dose (see above), but with the light sources commonly used, it is impossible to overdose the patient. Don't ignore a failure of response to phototherapy. If the bilirubin rises despite adequate phototherapy, there must be a reason. Consider the possibility of an unrecognized hemolytic process. Provide timely follow-up. Infants discharged (as most are) before 48 hours should be seen by a health-care professional within 2 to 3 days of discharge. Don't ignore prolonged jaundice. About one in three normal breast-fed infants still will be clinically jaundiced when they are 2 weeks old (two thirds will be biochemically jaundiced). These infants all have indirect hyperbilirubinemia. Occasionally, however, an infant with prolonged jaundice has direct hyperbilirubinemia. In these infants, the diagnosis of biliary atresia or some other cause of cholestatic jaundice must be considered. If the infant is clinically jaundiced beyond age 2 weeks, you should: 1) check the newborn record to make sure that the metabolic screen for hypothyroidism is normal (congenital hypothyroidism is a cause of indirect hyperbilirubinemia), and 2) ask the mother about the color of the urine and stool. If the baby's stools are pale or the urine is dark yellow, you must get a direct bilirubin to rule out cholestasis. If there is direct hyperbilirubinemia, a urine dipstick will identify the presence of bile (bilirubin). If the color of the urine and stool are normal (by history), it is reasonable to follow the child for another week. However, any infant who is still jaundiced beyond age 3 weeks must have a measurement of direct bilirubin. Don't ignore severe jaundice. If the bilirubin is sufficiently elevated, kernicterus can occur in a healthy, breast-fed infant.