Prospective comparative study of cefotetan with piperacillin for prophylaxis against infection in elective colorectal surgery.

This study compared one dose of cefotetan with three doses of piperacillin as prophylaxis against wound infection in 153 patients undergoing elective colorectal surgery. The patients were randomized into two groups: the first received 2 g cefotetan intravenously with induction of anaesthesia (n = 75), and the second received three doses of 2 g piperacillin (n = 78). Wound infection was defined as the presence of an abscess or discharging pus from the wound. In the cefotetan group there were 14 (19%) wound infections and 13 (17%) in the piperacillin group. There were three septic deaths, one in the cefotetan group and two in the piperacillin group. Both groups were comparable with regard to age, sex, nature of pathology and pre- and perioperative risk factors. No significant haematological or biochemical abnormalities were detected. The only adverse reaction was one patient who had an allergic reaction (rash) to piperacillin. These data suggest that single-dose cefotetan is as effective as triple-dose piperacillin in prophylaxis against infection in elective colorectal surgery.

The natural history of murine intra-abdominal abscess formation.

We determined the natural history of experimental abscess formation and had a secondary interest in the effect of muramyl dipeptide. Swiss-Webster mice were injected intraperitoneally with autoclaved mouse fecal suspension and either Bacteroides fragilis (10(8) colony-forming units [cfu]/mL) alone or Escherichia coli (10(4) cfu/mL), enterococcus (10(3) cfu/mL), and B fragilis (10(5) cfu/mL) after pretreatment with muramyl dipeptide or saline solution. All deaths occurred within 48 hours of injection and surviving mice, including those bearing abscesses, appeared to be healthy throughout the study. The number of mice with abscesses and the number of abscesses per group were at their maximum at two to four weeks. Groups with live bacteria had a substantial reduction in the number of abscesses between eight and 26 weeks, compared with two- and four-week values. Manual rupture of palpably large eight-week-old abscesses in 21 mice produced only one death and at autopsy two weeks later, all of the mice showed multiple smaller abscesses. Abscess formation appeared to be beneficial and the natural history of such may include spontaneous resolution without mortality.

Effect of interferon-gamma treatment on the course of a burn wound infection.

Interferon-gamma (IFN-gamma) has been shown to have immunoregulatory properties and is able to modulate resistance to several microbial infections. This study was designed to determine the efficacy of IFN-gamma treatment in a murine burn wound infection model. Bacterial challenge consisted of Klebsiella pneumoniae (10(8) organisms/ml) or Pseudomonas aeruginosa (10(8) organisms/ml), applied topically immediately after burning. Groups of CBA/J mice received either IFN-gamma or RPMI-1640 medium (controls) subcutaneously. IFN-gamma was administered daily at a dose of 7,500 units for 5 days prior to bacterial challenge. Burn without bacterial challenge produced no mortality. Mice treated with IFN-gamma survived significantly longer than controls when the bacterial challenge was K. pneumoniae. There was no difference in survival when bacterial challenge was P. aeruginosa. The Ia antigen expression of peripheral blood mononuclear cells was severely reduced for 3 days post-burn. This drop was prevented on day 3 post-burn in mice treated with IFN-gamma. These data indicate that interferon was effective treatment in a murine model of Klebsiella burn wound infection and was associated with maintenance of Ia antigen expression that may have contributed to the action of the IFN-gamma.