Background: Hyperbilirubinemia and liver enzyme abnormalities are commonly observed in sepsis. However, the frequency in premature neonates and the specific relation to gram-negative bacteria are not known.
Patients and methods: Charts of all preterm infants who had positive blood cultures for either gram-negative bacteria or coagulase-negative staphylococci were reviewed. Neonates with gram-negative bacteremia (n = 54) were compared with neonates with coagulase-negative staphylococcal bacteremia (n = 31). In addition infants with gram-negative bacteremia and elevated liver enzymes (n = 25) were compared with infants with gram-negative bacteremia and normal liver enzymes (n = 29).
Results: Liver enzyme abnormalities accompanied 46.3% (25 of 54) of gram-negative bacteremia and 12.9% (4 of 31) of episodes of coagulase-negative staphylococcal bacteremia (P = 0.002). Serum concentrations of liver enzymes were significantly higher in infants with gram-negative bacteremia than in those with coagulase-negative staphylococcal bacteremia (P < 0.0001), but no difference in alkaline phosphatase serum values was observed. Infants with gram-negative bacteremia and elevated liver enzymes were not fed for a longer period than infants with gram-negative bacteremia and normal liver enzymes (7.3 +/- 6.3 days vs. 4.0 +/- 4.3 days, P = 0.03), and this was accompanied by significant conjugated hyperbilirubinemia (P < 0.0001). Ventilation, total parenteral nutrition and medications were not responsible for the observed differences. Klebsiella pneumoniae bacteremia was commonly associated with elevated liver enzymes (12 of 18), whereas none of the infants with Pseudomonas aeruginosa bacteremia had elevated liver enzymes.
Conclusions: Gram-negative bacteremia is commonly associated with cholestasis in premature neonates. Liver enzyme abnormalities are more common than elevated conjugated bilirubin, not all gram-negative bacteria have the same effect and the lack of enteral feeding seems to play a more significant role than the administration of parenteral nutrition.