Treatment of infections caused by multidrug-resistant Gram-negative bacteria: report of the British Society for Antimicrobial Chemotherapy/Healthcare Infection Society/British Infection Association Joint Working Party.

The Working Party makes more than 100 tabulated recommendations in antimicrobial prescribing for the treatment of infections caused by multidrug-resistant (MDR) Gram-negative bacteria (GNB) and suggest further research, and algorithms for hospital and community antimicrobial usage in urinary infection. The international definition of MDR is complex, unsatisfactory and hinders the setting and monitoring of improvement programmes. We give a new definition of multiresistance. The background information on the mechanisms, global spread and UK prevalence of antibiotic prescribing and resistance has been systematically reviewed. The treatment options available in hospitals using intravenous antibiotics and in primary care using oral agents have been reviewed, ending with a consideration of antibiotic stewardship and recommendations. The guidance has been derived from current peer-reviewed publications and expert opinion with open consultation. Methods for systematic review were NICE compliant and in accordance with the SIGN 50 Handbook; critical appraisal was applied using AGREE II. Published guidelines were used as part of the evidence base and to support expert consensus. The guidance includes recommendations for stakeholders (including prescribers) and antibiotic-specific recommendations. The clinical efficacy of different agents is critically reviewed. We found there are very few good-quality comparative randomized clinical trials to support treatment regimens, particularly for licensed older agents. Susceptibility testing of MDR GNB causing infection to guide treatment needs critical enhancements. Meropenem- or imipenem-resistant Enterobacteriaceae should have their carbapenem MICs tested urgently, and any carbapenemase class should be identified: mandatory reporting of these isolates from all anatomical sites and specimens would improve risk assessments. Broth microdilution methods should be adopted for colistin susceptibility testing. Antimicrobial stewardship programmes should be instituted in all care settings, based on resistance rates and audit of compliance with guidelines, but should be augmented by improved surveillance of outcome in Gram-negative bacteraemia, and feedback to prescribers. Local and national surveillance of antibiotic use, resistance and outcomes should be supported and antibiotic prescribing guidelines should be informed by these data. The diagnosis and treatment of both presumptive and confirmed cases of infection by GNB should be improved. This guidance, with infection control to arrest increases in MDR, should be used to improve the outcome of infections with such strains. Anticipated users include medical, scientific, nursing, antimicrobial pharmacy and paramedical staff where they can be adapted for local use.

Does laboratory antibiotic susceptibility reporting influence primary care prescribing in urinary tract infection and other infections?

OBJECTIVES: Using a prospective interrupted time series design, our goal was to determine whether a change in urine antibiotic susceptibility reporting from co-amoxiclav to cefalexin to community clinicians served by Southmead General Hospital led to a change in antibiotic prescribing. METHODS: We used longitudinal data on antibiotic prescribing using a clinician questionnaire to identify prescribing for urinary tract infections (UTIs) when a urine specimen was submitted to microbiology; MIQUEST computer search in general practices for prescribing for all UTIs in the community; and Prescribing Analysis and Cost (PACT) data to determine antibiotic prescribing for all infections. RESULTS: Cefalexin and cephalosporin prescribing increased when cefalexin was reported and co-amoxiclav prescribing decreased when co-amoxiclav was not reported by the laboratory. This was seen for episodes of UTI in which a general practitioner (GP) sent a specimen as determined with: the questionnaire results (9-fold rise in cephalosporins, 70% fall in co-amoxiclav); episodes of UTI identified by MIQUEST searches in the practice (50% increase in cefalexin, 25% reduction in co-amoxiclav); and overall antibiotic prescribing in the practice determined with PACT data (20% increase in cefalexin, 8% reduction in co-amoxiclav). MIQUEST data indicated that prescribing reverted to pre-intervention levels once the change in antibiotic reporting had stopped. CONCLUSIONS: Our data provide more evidence that changing laboratory antibiotic susceptibility reporting has a direct effect on antibiotic prescribing by GPs. Our data indicate that much of the change in prescribing was attributable to the use of cefalexin and co-amoxiclav for persistent or recurrent infections. Microbiology laboratories can influence antibiotic use by selectively reporting antibiotics they would prefer GPs to prescribe.