The value of chemoprophylaxis against Enterococcus species in elective cholecystectomy: a randomized study of cefuroxime vs ampicillin-sulbactam.

HYPOTHESIS: Cephalosporins are widely used and considered to be effective as prophylaxis in biliary surgery. Nevertheless, they lack activity against enterococci. We conducted a study to compare the efficacy of ampicillin-sulbactam vs cefuroxime in preventing surgical site infections following elective cholecystectomy. DESIGN: A prospective randomized controlled trial. SETTING: A major tertiary care hospital. PATIENTS: Four hundred eighteen randomized patients (of 549 total), who from July 2002 to August 2004 underwent elective open or laparoscopic cholecystectomy with prospective assessment for development of surgical site infections for 1 month postoperatively. INTERVENTION: A single intravenous dose of 1.5 g of cefuroxime (group A, n = 207) or 3 g of ampicillin-sulbactam (group B, n = 211) was administered during induction of anesthesia. Bile and gallbladder mucosal cultures were taken intraoperatively from all patients. MAIN OUTCOME MEASURE: Number of postoperative surgical site infections. RESULTS: A postoperative surgical site infection was noted in 19 (4.5%) of 418 patients, 18 from group A and 1 from group B (P<.001). In the group that received cefuroxime, 15 (83.3%) of 18 surgical site infections were due to Enterococcus species. Intraoperative bactibilia as well as intraoperative gallbladder rupture were associated with surgical site infections (P<.001). CONCLUSIONS: A single dose of ampicillin-sulbactam favored better compared with cefuroxime for prevention of postoperative surgical site infections due to Enterococcus species after elective cholecystectomy. Ampicillin-sulbactam may be a better agent for antimicrobial prophylaxis in high-risk patients undergoing elective cholecystectomy, especially in a setting where the incidence of enterococcal infections is higher.

Multidrug resistance to antimicrobials as a predominant factor influencing patient survival.

The impact of multidrug resistance to antimicrobials was assessed in a cohort of 243 patients with microbiologically documented infections by a variety of susceptible and multidrug-resistant (MDR) species. Multidrug resistance was defined as resistance to more than two antimicrobial agents of different chemical structure. Cox regression analysis was performed to define differences and the significance of any predisposing factors. Overall survival of patients infected by susceptible isolates was prolonged compared with patients infected by MDR isolates (P=0.013). Mortality rates of infections caused by susceptible and MDR isolates were 4.87% and 16.15%, respectively (P=0.013); the higher mortality rate for MDR isolates was more pronounced for infections by Klebsiella pneumoniae and Pseudomonas aeruginosa. Mean (+/-standard error (S.E.)) survival of patients infected by susceptible and MDR isolates in patients without signs of severe sepsis was 28 days and 27.29+/-0.35 days, respectively (P=not significant). Mean (+/-S.E.) survival of patients with severe sepsis caused by susceptible and MDR isolates was 7.70+/-4.62 days and 10.45+/-2.18 days, respectively (P=0.048). Diabetes mellitus type 2, the presence of severe sepsis and any underlying malignancy were the most important risk factors affecting survival. It is concluded that infections by MDR isolates were accompanied by higher mortality rates and decreased survival compared with infections by susceptible isolates. Diabetes mellitus type 2 and underlying malignancies were significant co-morbid conditions, whereas survival after infection by susceptible isolates was particularly decreased in the event of severe sepsis.

Early changes of procalcitonin may advise about prognosis and appropriateness of antimicrobial therapy in sepsis.

PURPOSE: The objective of this study is to define if early changes of procalcitonin (PCT) may inform about prognosis and appropriateness of administered therapy in sepsis. METHODS: A prospective multicenter observational study was conducted in 289 patients. Blood samples were drawn on day 1, that is, within less than 24 hours from advent of signs of sepsis, and on days 3, 7, and 10. Procalcitonin was estimated in serum by the ultrasensitive Kryptor assay (BRAHMS GmbH, Hennigsdorf, Germany). Patients were divided into the following 2 groups according to the type of change of PCT: group 1, where PCT on day 3 was decreased by more than 30% or was below 0.25 ng/mL, and group 2, where PCT on day 3 was either increased above 0.25 ng/mL or decreased less than 30%. RESULTS: Death occurred in 12.3% of patients of group 1 and in 29.9% of those of group 2 (P < .0001). Odds ratio for death of patients of group 1 was 0.328. Odds ratio for the administration of inappropriate antimicrobials of patients of group 2 was 2.519 (P = .003). CONCLUSIONS: Changes of serum PCT within the first 48 hours reflect the benefit or not of the administered antimicrobial therapy. Serial PCT measurements should be used in clinical practice to guide administration of appropriate antimicrobials.

In vitro elution of moxifloxacin from cancellous bone allografts.

The characteristics of cancellous bone allografts as carriers of moxifloxacin are described. Particles of cancellous bone were compressed into a wire-mesh cylinder and impregnated into a solution of moxifloxacin for different time periods. Five replicas were impregnated for 1 h; another five for 24 h; and another five for 48 h. Impregnated allografts were then transferred into vials containing 5 ml of Mueller-Hinton broth and incubated at 37 degrees C. Broth was replaced daily. Concentrations of moxifloxacin in broth were determined after analysis by an high performance liquid chromatography system. Moxifloxacin was eluted at very high concentrations within the first days. Concentrations remained above 100 microg/ml until day 8 and above 40 microg/ml until day 20. It is concluded that cancellous bone allografts may allow the adequate in vitro elution of moxifloxacin. The latter results support their application in experimental models of osteomyelitis.