Following the ban of all food animal growth-promoting antibiotics by Sweden in 1986, the European Union banned avoparcin in 1997 and bacitracin, spiramycin, tylosin and virginiamycin in 1999. Three years later, the only attributable effect in humans has been a diminution in acquired resistance in enterococci isolated from human faecal carriers. There has been an increase in human infection from vancomycin-resistant enterococci in Europe, probably related to the increased in usage of vancomycin for the treatment of methicillin-resistant staphylococci. The ban of growth promoters has, however, revealed that these agents had important prophylactic activity and their withdrawal is now associated with a deterioration in animal health, including increased diarrhoea, weight loss and mortality due to Escherichia coli and Lawsonia intracellularis in early post-weaning pigs, and clostridial necrotic enteritis in broilers. A directly attributable effect of these infections is the increase in usage of therapeutic antibiotics in food animals, including that of tetracycline, aminoglycosides, trimethoprim/sulphonamide, macrolides and lincosamides, all of which are of direct importance in human medicine. The theoretical and political benefit of the widespread ban of growth promoters needs to be more carefully weighed against the increasingly apparent adverse consequences.

No abstract

A prospective study of bacterial and fungal infections after liver transplantation in 284 adults was undertaken. One hundred seventy-five (62%) became infected; bacterial or fungal infections occurred in 159 (56%) and 36 (13%) patients, respectively. Gram-positive cocci, in particular Staphylococcus aureus and Enterococcus faecium, were the commonest bacterial pathogens, and bacteremia and wound infection were the most frequent bacterial infections. Acute rejection and prolonged admission were independent risk factors for bacterial infection; pretransplantation antibacterials had a protective effect. Fungal infection most frequently involved the urinary tract and chest; Candida albicans was the most common pathogen. Four independent variables predicted fungal infection: low pretransplantation hemoglobin, high pretransplantation bilirubin, return to surgery, and prolonged therapy with ciprofloxacin. Patients with acute liver failure were more prone to bacterial, but not fungal, infection. No associations were found between infections and duration of surgery. Bacterial, and to a lesser extent, fungal infections are important complications of liver transplantation. However, liver transplantation surgery per se may not be the major determinant of infection.

Fifty consecutive patients admitted with acute liver failure, minimal grade II encephalopathy, were studied prospectively to determine the incidence, timing and cause of bacterial infection, the relationship to clinical criteria for infection; and the influence of early microbiological diagnosis on clinical outcome. There were 53 proven bacterial infections in 40 patients, whereas in 5 of the remaining 10 patients infection was suspected on clinical grounds in the absence of significant cultures. Seven patients (14%) had more than one bacterial infection, and four patients had simultaneous infections caused by different organisms at each site. Fourteen infections (26.4%) were associated with bacteremia, and in six of these no source was found. Twenty-five infections (47.1%) arose from the respiratory tract, 12 (22.6%) from the urinary tract and 2 (3.7%) from central venous cannulas. Thirty-seven (69.8%) of the 53 infections were due to gram-positive bacteria; Staphylococcus aureus accounted for 19 (35.8%) of all the infections. Thirty patients died (60%), 28 of whom had bacterial infection at some time; in 24 of these the infection was diagnosed less than 24 hr before death. All nine deaths that occurred more than 7 days after admission were directly attributable to microbial infection. Clinical features such as elevated temperature and elevated peripheral white blood cell count were poor indicators of bacterial infection because these were absent in 30.2% of cases. These data show that there is a high incidence of bacterial infection early in the course of acute liver failure and suggest that prophylactic antimicrobial therapy, although unproven, might be justified.