Nonphysiologic Hyperbilirubinemia

Nonphysiologic Hyperbilirubinemia

Those with primarily elevated direct bilirubin. Direct bilirubin >15% of total and therefore conjugated by the liver.
Infections including sepsis, perinatally acquired viral infections including hepatitis, and intrauterine viral infections (hepatitis B, TORCHS).
Metabolic abnormalities including Rotor syndrome and Dubin-Johnson syndrome.
Anatomic abnormalities including biliary atresia and obstructions as with a choledochal cyst.
Cholestasis from CVN/TPN antibiotics (especially ceftriaxone).
Galactosemia, tyrosinosis, cystic fibrosis, hereditary fructose intolerance.
Those with primarily elevated indirect bilirubin. Therefore not conjugated by liver. Two basic mechanisms:
From increased production of bilirubin (therefore hemolysis or hematoma breakdown).
With positive direct Coombs' test (mother's antibodies on child's cells). Isoimmunization (Rh, ABO, minor blood group), erythroblastosis fetalis.
With negative Coombs' test and RBC morphologic abnormalities. Spherocytosis, thalassemias, G6PD deficiency, elliptocytosis, etc.
Extravascular blood. Cephalohematoma, severe bruising, cerebral and pulmonary hemorrhage.
DIC, other hemolytic anemia
Polycythemia resulting from delayed clamping of cord, twin-twin transfusion, maternal-fetal transfusion.
From delayed excretion of bilirubin.
Inherited disorders of bilirubin metabolism including Crigler-Najjar syndrome, Gilbert's disease, Dubin-Johnson syndrome, Rotor syndrome.
Hypothyroidism and prematurity.