Biapenem versus imipenem/cilastatin in the treatment of complicated intra-abdominal infections: report from a Swedish Study Group.

118 patients with complicated intra-abdominal infections participated in an open randomized comparative multicenter trial in order to compare the clinical and microbiological efficacy and safety of biapenem with imipenem/cilastatin (Tienam). 31 men and 27 women (mean age 52.3 years) were enrolled in the biapenem group, and 43 men and 17 women (mean age 52.3 years) in the imipenem/cilastatin group. The patients received either biapenem 500 mg every 8 h or imipenem/cilastatin 500 mg/500 mg every 6 h by intravenous infusion for up to 13 days (mean 6.5 days). 28/43 evaluable patients (65.1%) receiving biapenem and 27/40 evaluable patients (67.5%) in the imipenem/cilastatin group were clinically cured. The microbiological response was satisfactory in 28/43 evaluable patients (65.1%) receiving biapenem and in 27/40 evaluable patients (67.5%) receiving imipenem/cilastatin. No significant differences in clinical or microbiological efficacy between the two treatment groups were found. The present study shows that biapenem may be useful in the treatment of intra-abdominal infections.

Effect of piperacillin/tazobactam treatment on human bowel microflora.

The effect of piperacillin/tazobactam treatment on the bowel microflora was studied in 20 patients with intra-abdominal infections. The patients were treated with piperacillin 4 g and tazobactam 500 mg administered intravenously every 8 h for four to eight days. Stool specimens were collected before, during and after treatment. Six patients had measurable faecal concentrations of piperacillin (1.2-276 mg/kg) and four patients measurable concentrations of tazobactam (0.8-22.2 mg/kg) during treatment. The mean numbers of enterobacteria, enterococci, bifidobacteria, eubacteria, lactobacilli, clostridia and Gram-positive cocci decreased while the numbers of anaerobic Gram-negative cocci and bacteroides were unaffected. The aerobic and anaerobic microflora returned to normal in all patients after the treatment had stopped.

Effect of piperacillin/tazobactam therapy on intestinal microflora.

The effect of piperacillin/tazobactam treatment upon the intestinal microflora was studied in 20 patients with intraabdominal infections. The patients received piperacillin 4 g combined with tazobactam 500 mg q 8 h by intravenous injection for 4-8 days. Stool specimens were collected before, during and after therapy for cultivation of aerobic and anaerobic microorganisms. Six patients had measurable concentrations of piperacillin (1.2-276 mg/kg/faeces) and 4 patients tazobactam concentrations (0.8-22.2 mg/kg/faeces) in the faecal specimens during therapy. The number of enterobacteria and enterococci slightly decreased while there were no changes in the number of staphylococci and bacilli. The anaerobic microflora was also slightly affected. There was a minor decrease in the number of bifidobacteria, eubacteria, lactobacilli, clostridia and veillonella but the numbers of anaerobic Gram-positive cocci and bacteroides were not influenced by the treatment. After therapy, the aerobic and anaerobic microflora returned to normal levels in all patients. None of the patients had Clostridium difficile or cytotoxin in the stools or developed diarrhoea.

Selective antibiotic prophylaxis in biliary tract operations.

A prospective study of 397 patients with primary biliary operations performed for benign disease included a perioperative culture of the bile. Two main groups of patients in whom bacteria in the bile and, thus, probably increased risk postoperative infection was common, are patients undergoing emergency operation (60 per cent bacteria in the bile, as compared with 22 per cent in those with elective operations) and patients with a history of acute cholecystitis or pancreatitis, or both, or jaundice (49 per cent bacteria in the bile with a positive history as compared with 11 per cent without). The rate of infection was 2.8 per cent in high-risk groups, as compared with 0.6 per cent in patients undergoing elective operative procedures with no history of acute cholecystitis, pancreatitis or jaundice. Thus, antibiotics can probably be reserved for those patients who had emergency surgical treatment and for those with elective operations and a history of acute cholecystitis, pancreatitis or jaundice. In addition, antibiotic prophylaxis might be indicated for all patients who are 75 years of age or older, as bacteria in the bile seems to be common in this age group even without a history of the aforementioned complications.

Antibiotics in acute abdominal surgery. A clinical trial comparing the combination of ampicillin, mecillinam and metronidazole with cefoxitin alone.

168 patients undergoing acute abdominal surgery for suspected peritoneal contamination were randomized consecutively to receive either a combination of ampicillin, mecillinam and metronidazole (group I) or cefoxitin (group II). Seventy-nine patients were evaluable in group I and 69 in group II. Postoperative surgical infections were seen in a total of 17 patients, 6 in group I (7.6%) and 11 in group II (15.9%). Evaluation of potential resistance development, side-effects and a trend towards better efficacy, together with a positive cost benefit analysis, have led us to adopt the combination of ampicillin, mecillinam and metronidazole as the standard treatment in cases of acute abdominal surgery. In the 18 months following the conclusion of the study, 263 patients undergoing acute abdominal surgery were treated with the triple combination. The infection rate in this material was 4.6%.