Snapshot A healthy 2-week-old male presents with mild jaundice. He was born at term. Labs show a total billirubin of 18 mg/dl (normal <7 mg/dl), and a direct billirubin of 0.8 mg/dl (normal 0-0.4). Introduction Physiologic jaundice occurs between days 3-5 and is clinically benign indirect (unconjugated) bilirubin commonly rises to 9 mg/dl days 3-5 & begins to fall occurs in 50% of neonates during the first week of life results from increased bilirubin production and relative deficiency in glucuronyl transferase in the immature liver Pathologic jaundice The presence of the following factors in an infant is indicative of pathologic jaundice and warrants evaluation for an underlying etiology: 1) Jaundice in the first 24 hours of life is always pathologic 2) Total serum bilirubin > 12 mg/dL in a term infant 3) Conjugated bilirubin > 2 mg/dL or > 20% of total bilirubin level 4) Total serum bilirubin rate of rise > 5 mg/dL/day 5) Persistence of jaundice beyond 10-14 days 6) Presence of any additional signs or symptoms indicative of potential underlying diseasedirect (conjugated) bilirubinemia Bilirubin levels > 20 mg/dL can lead to kernicterus and associated neurotoxicity Results from the irreversible deposition of billirubin in the basal ganglia, pons, and cerebellum Potentially fatal Indirect (unconjugated) hyperbilirubinemia occurs in Criggler-Najjar syndrome Gilbert's syndrome Congenital hypothyroidism Breast feeding failure caused by insufficient breast milk consumption reduced oral intake results in inadequate quantities of bowel movements to excrete bilirubin from the body improves with increased breast milk intake Breast milk infant liver is not mature enough to process lipids presents between 4th and 7th day of life indirect bilirubin as high as 27 mg/dl during the 3rd week of life no intervention needed (mother does not need to stop breast feeding) if breast feeding stops, bilirubin levels fall rapidly if breast feeding continues, bilirubin levels will fall slowly Hemolytic anemia leading to hyperbilirubinemia caused by hereditary spherocytosis G6PD-deficiency pyruvate kinase deficiency ABO/Rh isoimmunization acute or chronic infection drugs maternal diabetes chronic fetal hypoxia cephalohematoma Conjugated (direct) hyperbilirubinemia occurs in infections galactosemia alpha-1-antitrypsin deficiency congenital causes include extrahepatic biliary atresia Dubin-Johnson syndrome Rotor syndrome Presentation Neonates may be jaundiced with bilirubin levels > 5 mg/dl Presents on physical exam with yellowish discoloration of the skin (progresses from head to toe with increasing bilirubin levels) and scleral icterus Billirubin levels rising above 9 are considered abnormal and need treatment Additionally, the presence of a factor listed above under "pathologic jaundice" always necessitates further work-up to determine a potential cause for the infant's jaundice STUDIES Blood smear may show hemolysis in cases where indirect bilirubin alone is elevated Coombs' test used to distinguish between immune mediated hemolytic disorders (ABO incompatability) and non-immune-mediated hemolytic disorders including G6PD deficiency hereditary spherocytosis LFTs, alk phos, bile acids, and sweat test may identify diagnosis if direct bilirubin is elevated help rule out aminoacidopathies and alpha-1-antitrypsin deficiency Septic work-up indicated in any jaundiced neonate with fever, hypotension, and tachypnea Maternal-fetal ABO and Rh incompatibilites may identify immune-related hyperbilirubinemia Differential Within 24 hoursHemolysis (ABO/Rh isoimmunization or hereiditary spherocytosis)Within 48 hoursHemolysisInfectionPhysiologicAfter 48 hoursInfectionHemolysisBreast MilkCongenital malformation (biliary atresia)Hepatitis Treatment Prevention preventive measures are usually not available stop breast-feeding to speed resolution of neonatal jaundice, though not required avoid drugs that result in hemolytic anemia in certain patient groups Medical management no treatment indicated in physiologic jaundice treat underlying infectious causes phototherapy indicated when bilirubin levels > 15-20 mg/dl regardless of cause Specific nomograms exist to govern when blue-light therapy is indicated exchange transfusion may be indicated in very severe cases of hyperbilirubinemia Complications Retinal damage, dehydration, dermatitis, and diarrhea all related to UV exposure Prognosis Ranges widely Can spontaneously resolve or be fatal depending on etiology