Neonatal Hemolytic Jaundice
Hyperbilirubinemia ( severe jaundice ) is the most common condition requiring re-hospitalization during the first week of life. Total Serum Bil (TSB) > 17 mg/dl ≈ 10% Total Serum Bil (TSB) > 20 mg/dl ≈ 1.5%
Most neonates with extreme hyperbilirubinemia have no underlying etiology. 55% to 66% of neonates with a TSB >30 mg/dl have no etiology (idiopathic jaundice), according to 2 studies.
Hyperbilirubinemia = bilirubin production - bilirubin elimination Low activity of UGT1A1 ≈ 1% in newborns (diminished conjugation in all newborns) Prodominant factor in severe jaundice is increased bilirubin production (hemolysis)
Increased risk of neurotoxicity Why hemolytic jaundice is important? Increased risk of neurotoxicity
Hemolytic jaundice is likely when: jaundice observed in first 24 hours pre-discharge Bil in high risk zone rising Bil more than 0.5 mg/dl/h cord Bil more than 4 mg/dl prolonged hyperbilirubinemia low hemoglobin ( < 13 g/dl) positive direct anti-globulin test (DAT) Elevated reticulocyte count
Hemolytic jaundice is likely when: hepatosplenomegaly finding hemoglobin without erythrocytes in urine pink serum on a visual examination of a blood sample absence of haptoglobin in the serum
ABO hemolytic disease Indirect hyperbilirubinemia during the first 24h of life Mother with blood group O, infant with blood group A or B Spherocytosis on blood smear Increased reticulocyte count Evidence of hemolysis based on increased endogenous production of CO Direct or indirect coombs positive
Incompatibility to other RBC antigens Anti -c Anti -E Anti-Kell
Five diagnostic tests or approaches useful in hemolytic jaundice Erythrocyte morphology End-tidal carbon monoxide (ETCO) measurement EMA flow cytometry for HS and other membrane defects NGS (Next Generation Sequencing) of relevant genes An algorythm in judicious use of standard tests
Prediction of Hemolytic Jaundice Cord bilirubin Clincal risk factors Hour-specific bilirubin nomogram
Hour-specific Bilirubin Nomogram
Treatment Phototherapy Exchange transfusion IVIG
Guidelines for Exchange Transfusion