Management of Hyperbilirubinemia at 28 Days of Age

Initial Evaluation

The American Academy of Pediatrics recommends that any infant with clinical jaundice at 28 days of age should be immediately evaluated with total and direct (or conjugated) bilirubin to rule out cholestasis, a potentially serious condition such as biliary atresia that requires urgent intervention 1, 2
Infants with persistent jaundice beyond 3 weeks of life require immediate investigation, including measurement of total and direct/conjugated bilirubin to identify cholestasis (direct hyperbilirubinemia) 1, 2
The initial evaluation should also include verification of newborn screening results for hypothyroidism and galactosemia, as congenital hypothyroidism can cause indirect hyperbilirubinemia 1

If direct bilirubin is elevated (cholestasis), the evaluation should include urinalysis and urine culture 1, 3
An evaluation for sepsis should be considered if indicated by history and physical examination 1
Consideration should be given to hepatic ultrasound and evaluation by pediatric gastroenterology to rule out biliary atresia 2

At 28 days of life, phototherapy is generally not indicated even if bilirubin levels exceed typical thresholds for phototherapy, because the risk of bilirubin neurotoxicity decreases substantially with postnatal age 4
However, phototherapy may be indicated in high-risk scenarios, including active hemolytic disease 2, rapid rate of bilirubin elevation 4, and serum bilirubin levels approaching exchange transfusion levels (≥25 mg/dL) 2

Do not rely solely on visual assessment of jaundice: always obtain measurements of serum total bilirubin, especially in infants with dark skin pigmentation 2, 3
Do not delay evaluation of cholestasis: biliary atresia requires surgery (Kasai procedure) ideally before 60 days of life for best outcomes 2

For infants with confirmed benign indirect hyperbilirubinemia, ensure adequate feeding (8-12 feedings per day if breastfeeding) and follow-up clinically in 1 week if jaundice persists 2, 3
For infants with cholestasis or any elevation of direct bilirubin, urgent referral to pediatric gastroenterology and complete evaluation for causes of cholestasis are necessary 1, 2