Efficacy of Liposomal Antibiotic Therapy in a Rat Infusion Model of Escherichia Coli Peritonitis


  1. Martineau, L.
  2. Shek, P.N.
Corporate Authors
Defence and Civil Inst of Environmental Medicine, Downsview ONT (CAN)
To compare the potential therapeutic effect of liposomal vs. free cefoxitin. Randomized, controlled study, using a rat model of peritonitis. Government research facility. Male Sprague-Dawley rats. Rats were infused intraperitoneally with 6.5 c E8 colony forming units of Escherichia coli over 12 hrs. Animals were then randomized to receive intravenous saline, free cefoxitin, liposomal cefoxitin, or plain liposomes twice daily until they were killed. Free cefoxitin significantly reduced the number of E. coli after 24 hrs compared with saline treatment in both liver and spleen. However, liposomal cefoxitin further decreased the bacterial content by five-fold to ten-fold in these organs. Minimal bactericidal effect was observed in animals injected with plain liposomes. although administration of liposomal cefoxitin for 7 days further reduced bacterial counts in liver and spleen, there was no apparent beneficial bactericidal effect of free cefoxitin over saline at 7 days. There was approximately a ten-fold reduction in bacterial content in the lungs after 24 hrs in all three treatments, but no further reduction was observed after 7 days. there was no difference in 7-day survival rate in animals treated with plain liposomes or saline (45% vs. 39%). Although survival tended to increase with free cefoxitin treatment (64%), this outcome was significantly improved with the use of liposomal cefoxitin (82%). TRUNCATED
Sepsis;Animal model;Peritonitis;bacterial infections;Cefoxitin;Efficacy
Report Number
DCIEM-98-P-21 — Reprint
Date of publication
30 Dec 1999
Number of Pages
Reprinted from
Crit Care Med, vol 27, no 6, 1999, p 1153-1158
Hardcopy;Document Image stored on Optical Disk

Permanent link

Document 1 of 1

Date modified: