Breast milk jaundice

Background

Newborns produce bilirubin at a rate that exceeds adults due to the relative polycythemia and increased RBC turnover.. Breastmilk jaundice is an indirect hyperbilirubinemia in breastfed newborn that develops within the first 4-7 days of life. It does not generally cause kernicterus.

Cause

The etiology is unknown but may be related to inflammatory cytokines in human milk and the presence epidermal growth factor.

Clinical Features

• Jaundice within the first 4-7 days of life

Differential Diagnosis

Indirect (Unconjugated) Hyperbilirubinemia

More common causes are listed first, followed by less common causes

• Breast milk jaundice
  • Due to substances in milk that inhibits glucuronyl transferase. It may start as early as 3rd day and reaches peak by 3rd week of life. It is unlikely to cause kernicterus
• Breast feeding jaundice
  • Patient does not receive adequate oral intake which then causes reduced bowel movement/bilirubin excretion. Best diagnosed by looking for signs of dehydration and comparing weight to birth weight.
• Blood group incompatibility: ABO, Rh factor, minor antigens
• Diabetic mother/gestational diabetes
• Internal hemorrhage
• Physiologic jaundice
• Polycythemia
• Sepsis
• Hemoglobinopathies: thalassemia
• Red blood cell enzyme defects: G6PD Deficiency, pyruvate kinase
• Red blood cell membrane disorders: spherocytosis, ovalocytosis
• Hypothyroidism
• Immune thrombocytopenic purpura
• Mutations of glucuronyl transferase (i.e., Crigler-Najjar syndrome, Gilbert syndrome)

Direct (Conjugated) Hyperbilirubinemia

Conjugated bilirubinemia implies a hepatic or post hepatic cause. More common causes are listed first.

• Hyperalimentation cholestasis
• Neonatal hepatitis
• Cytomegalovirus infection
• Sepsis
• TORCH infection (toxoplasma, other/syphilis, rubella, CMV, HSV)
• Biliary atresia
• Cystic fibrosis
• Hepatic infarction
• Inborn errors of metabolism (e.g., galactosemia, tyrosinosis)

Evaluation

Neonatal jaundice workup

The most important component of the workup is differention of direct vs indirect bilirubinemia

• Total and direct bilirubin levels ("neonatal bilirubin")
• CBC (for evaluation of hemolytic anemia or polycythemia vera)
• Consider coombs or T&S (mom & baby)

Neonatal jaundice diagnosis

1. Determine if there are red flags or obvious diagnosis based on history and exam
   • Mother's blood type (important if mother is RH negative or O blood type)
   • Assess for any signs of decreasing oral intake or signs of dehydration?
   • Baby's general appearance (well appearing? evidence of sepsis?)
2. Determine bilirubinemia type: direct vs indirect
   • Direct
     • Admit
   • Indirect
     • Determine risk category
       • See table below
     • Determine if patient is above of below bilirubin cutoff by age and risk category
       • See table below or use BiliTool or phototherapy guide