Potentiation of Staphylococcus epidermidis catheter-related bacteremia by lipid infusions

Lipid infusions given to low-birth-weight neonates are associated with coagulase-negative staphylococcal bacteremia. A rabbit model of catheter-related Staphylococcus epidermidis bacteremia was used to compare infection rates between animals receiving 20% lipid infusions with those receiving 10% glucose infusions. Bacterial growth was detected in 43 (66%) of 65 blood cultures obtained during lipid infusions but only 6 (7%) of 91 blood cultures obtained during glucose infusions (P < .001). S. epidermidis was cultured from 7 of 9 catheters recovered from lipid-infused rabbits but from only 3 of 13 catheters from glucose-infused rabbits (P = .016). Lipid but not glucose solutions containing low levels of protein (0.1%-1.0%) supported the survival and growth of S. epidermidis. These results suggest that lipids contribute to the survival and growth of S. epidermidis on contaminated catheters, enhancing the potential of these organisms to disseminate and cause bacteremia.