Antimicrobial resistance profiles of Campylobacter from humans, retail chicken meat, and cattle feces.

We determined the antimicrobial resistance profiles of Campylobacter isolates from cases of sporadic human infection (n = 119), retail chicken meat (n = 105), and cattle feces (n = 105). Ampicillin and tetracycline resistance was highest in human isolates (32% and 29%, respectively) and retail chicken isolates (25% and 25%, respectively), whereas nalidixic acid resistance was highest in cattle fecal isolates (20%). We found that the antimicrobial resistance profiles were more similar in human and chicken meat isolates than those observed when comparing human and cattle fecal isolates. When we analyzed the distribution of minimum inhibitory concentrations for each antibiotic, in each host, the distribution was similar between human and chicken meat isolates, whereas cattle fecal isolates remained highly distinct from the other two hosts. This study suggests that chicken may be a major source of human Campylobacter infection and that the antimicrobial resistances found in the Campylobacter from this source will therefore also be prevalent in clinical isolates.

Rapid molecular testing for Staphylococcus aureus bacteraemia improves clinical management.

Introduction. Staphylococcus aureus bacteraemia (SAB) causes significant morbidity and mortality. Standard diagnostic methods require 24-48 h to provide results, during which time management is guideline-based and may be suboptimal.Aim. Evaluate the impact of rapid molecular detection of S. aureus in positive blood culture bottle fluid on patient management.Methodology. Samples were tested prospectively at two clinical centres. Positive blood cultures with Gram-positive cocci in clusters on microscopy were tested with the Xpert MRSA/SA blood culture assay (Cepheid), as well as standard culture-based identification and antimicrobial sensitivity tests. Results were passed to clinical microbiologists in real time and used for patient management.Results. Of 264 blood cultures tested (184 and 80 from each centre), S. aureus was grown from 39 (14.8 %) with one identified as methicillin-resistant S. aureus; all Xpert results agreed with culture results. Median turnaround time from culture flagging positive to result reporting for Xpert was 1.7 h, compared to 25.7 h for species identification by culture. Xpert results allowed early changes to management in 40 (16.8 %) patients, with Xpert positive patients starting specific therapy for SAB and Xpert negative patients stopping or avoiding empiric antimicrobials for SAB.Conclusion. Rapid and accurate detection of S. aureus with the Xpert MRSA/SA BC assay in positive blood culture bottles allowed earlier targeted patient management. Negative Xpert results are suggestive of coagulase negative staphylococci, allowing de-escalation of antimicrobial therapy if clinically appropriate.

Antibiotic stewardship and consumption: findings from a pan-European hospital study.

OBJECTIVES: Much has been written about antibiotic stewardship although less is known about the structure and content of antibiotic policies at hospital level. As part of the European Commission Concerted Action Antibiotic Resistance Prevention And Control (ARPAC) Project, data on antibiotic stewardship were collated and relationships investigated by antibiotic consumption in European hospitals. METHODS: A questionnaire survey on antibiotic stewardship factors was completed by 170 hospitals from 32 European countries. Data on committees, antibiotic formularies and policies addressing empirical therapy and prophylaxis were collated. Data on antibiotic use, expressed as defined daily doses per 100 occupied bed-days (DDD/100 BD), were provided by 139 hospitals from 30 countries, and 124 hospitals provided both data sets. Six key indicator stewardship variables were analysed by European region, case mix and antibiotic consumption. RESULTS: Hospitals from Northern and Western Europe were more likely to convene antibiotic committees or drugs and therapeutic committees compared with those from Southern and South-Eastern Europe (P < 0.001). One-fifth of hospitals had neither an antibiotic committee nor a policy. Hospital antibiotic policies commonly included recommendations on individual drugs, drug choices, dosage, duration and route but were less likely to contain information on side effects and cost. There were no significant differences by median total (J01) antibiotic consumption, although other antibiotic subgroups differed by stewardship indicators. CONCLUSIONS: Policies and practices relating to antibiotic stewardship varied considerably across European hospitals. These data provide a benchmark for newer European strategies tackling antibiotic resistance. More work is required to achieve harmonization of recommended practice, particularly in hospitals from Southern Europe.

Topical antimicrobials in combination with admission screening and barrier precautions to control endemic methicillin-resistant Staphylococcus aureus in an Intensive Care Unit.

We aimed to establish whether screening for methicillin-resistant Staphylococcus aureus (MRSA) and body decontamination upon admission to an Intensive Care Unit (ICU), in combination with barrier precautions, reduced rates of MRSA infection acquired on the unit. This was an interrupted time series study employing segmented regression analysis of data collected for all patients admitted to a 16-bed adult ICU over 48 months. Before the intervention (24 months; 1232 patients (44% female)), MRSA was sought from clinical cultures only and positive patients were barrier nursed in isolation. During the intervention (24 months; 1421 patients (54% female)), all ICU patients were screened for MRSA on admission and were barrier nursed in single rooms when established as MRSA-positive; all were given topical nasal anti-MRSA preparations and daily bed baths with 4% chlorhexidine throughout their stay. Changes in the proportion of patients colonised or infected with MRSA in the ICU were assessed. Before the intervention, 193 new MRSA cases (16%) were identified from 1232 ICU admissions; during the intervention, this was reduced to 92 cases (6%) of 1421 admissions. By time series regression analysis, the proportion of patients with MRSA decreased by 11.38% from ca. 15% to ca. 5% (ca. three-fold reduction) (95% confidence interval 3.5-19.3%; P=0.005). Thus, treatment of 11 patients prevented 1 clinical case of MRSA. Mean length of stay decreased significantly (P<0.001). Although MRSA and methicillin-susceptible S. aureus bacteraemia rates dropped, the changes detected were not statistically significant. The proportion of patients with coagulase-negative staphylococcal bacteraemia decreased significantly (P<0.001) and the trend changed from increasing to decreasing (P<0.001), as did the trend in glycopeptide use (P=0.014). An inexpensive and easy to implement intervention to control MRSA in the ICU was highly successful without compromising antimicrobial susceptibility.

The role of microbiology and pharmacy departments in the stewardship of antibiotic prescribing in European hospitals.

This observational, cross-sectional study describes the role played by clinical microbiology and pharmacy departments in the stewardship of antibiotic prescribing in European hospitals. A total of 170 acute care hospitals from 32 European countries returned a questionnaire on antibiotic policies and practices implemented in 2001. Data on antibiotic use, expressed as Defined Daily Doses per 100 occupied bed-days (DDD/100 BD) were provided by 139 hospitals from 30 countries. A total of 124 hospitals provided both datasets. 121 (71%) of Clinical Microbiology departments and 66 (41%) of Pharmacy departments provided out of hours clinical advice. 70 (41%) of microbiology/infectious disease specialists and 28 (16%) of pharmacists visited wards on a daily basis. The majority of laboratories provided monitoring of blood cultures more than once per day and summary data of antibiotic susceptibility testing (AST) for empiric prescribing (86% and 73% respectively). Most of the key laboratory and pharmacy-led initiatives examined did not vary significantly by geographical location. Hospitals from the North and West of Europe were more likely to examine blood cultures more than once daily compared with other regions (p < 0.01). Hospitals in the North were least likely routinely to report susceptibility results for restricted antibiotics compared to those in the South-East and Central/Eastern Europe (p < 0.01). Hospital wards in the North were more likely to hold antibiotic stocks (100%) compared with hospitals in the South-East which were least likely (39%) (p < 0.001). Conversely, hospital pharmacies in the North were least likely to dispense antibiotics on an individual patient basis (16%) compared with hospital pharmacies from Southern Europe (60%) (p = 0.01). Hospitals that routinely reported susceptibility results for restricted antibiotics had significantly lower median total antibiotic use in 2001 (p < 0.01). Hospitals that provided prescribing advice outside normal working hours had significantly higher antibiotic use compared with institutions that did not provide this service (p = 0.01). A wide range of antibiotic stewardship measures was practised in the participating hospitals in 2001, although there remains great scope for expansion of those overseen by pharmacy departments. Most hospitals had active antibiotic stewardship programmes led by specialists in infection, although there is no evidence that these were associated with reduced antibiotic consumption. There was also no evidence that pharmacy services reduced the amount of antibiotics prescribed.

Reassessment of the cefaclor breakpoint for Streptococcus pneumoniae.

Discrepancies between proven clinical success of cefaclor and its relatively poor activity in vitro were investigated against eight pneumococcal isolates. The bacteriostatic minimum inhibitory concentration (MIC) (the concentration resulting in no growth/kill relative to the starting inoculum) was derived from time kill studies. Bioassay results demonstrated an in vitro half-life of >24 and 9 h for cefuroxime and cefaclor, respectively. The mean NCCLS MIC for cefaclor was 1.4 and 0.3 mg/l for cefuroxime. The corresponding mean bacteriostatic MICs were 0.24 and 0.16 mg/l. Whilst cefaclor NCCLS MICs were significantly higher compared with cefuroxime MICs (P = 0.00058) there was no statistical differences between the bacteriostatic MICs (P = 0.259). Bacteriostatic MIC determination established that cefaclor and cefuroxime are equally active against pneumococci.

Information contained in miscarriage-related websites and the predictive value of website scoring systems.

OBJECTIVES: To identify websites providing information about early pregnancy loss and compare this information with published guidelines from the Royal College of Obstetricians and Gynaecologists (RCOG). The value of 'Silberg' and 'Health on the net (HON)' website scoring systems in predicting the information provided via websites identified was assessed. STUDY DESIGN: A cross-sectional survey. SAMPLE: Nineteen websites identified via two search engines (http://www.lycos.co.uk and http://www.msn.co.uk). METHODS: Websites were searched for specific information in a structured manner and then scored by two independent observers against the website scoring systems and against a scoring system derived from guidelines published by the RCOG. MAIN OUTCOME MEASURES: Website scores against the scoring systems and against RCOG guidelines. RESULTS: Information concerning miscarriage contained within these websites was poor and scored accordingly against the RCOG guidelines (median score, 4.5/8). The website scoring systems did not predict the RCOG scores for a website (HON score R(S)=0.193 (95% confidence interval from -0.286 to 0.595), Silberg score, R(S)=0.035 (95% confidence interval from -0.426 to 0.482)). CONCLUSIONS: Few relevant websites were identified despite searching a large number via two search engines. The websites found did not answer our specific questions and consequently scored poorly against the RCOG guidelines. RCOG scores did not correlate with either scoring system. Web-based information for women attending with early pregnancy complications needs to be easily accessed and comprehensive. Written information given to women when seen with early pregnancy complications should include details of available comprehensive websites. Professional organisations, colleges or Government agencies should provide this type of information.

Meticillin-resistant Staphylococcus aureus (MRSA): global epidemiology and harmonisation of typing methods.

This article reviews recent findings on the global epidemiology of healthcare-acquired/associated (HA), community-acquired/associated (CA) and livestock-associated (LA) meticillin-resistant Staphylococcus aureus (MRSA) and aims to reach a consensus regarding the harmonisation of typing methods for MRSA. MRSA rates continue to increase rapidly in many regions and there is a dynamic spread of strains across the globe. HA-MRSA is currently endemic in hospitals in most regions. CA-MRSA clones have been spreading rapidly in the community and also infiltrating healthcare in many regions worldwide. To date, LA-MRSA is only prevalent in certain high-risk groups of workers in direct contact with live animals. CA-MRSA and LA-MRSA have become a challenge for countries that have so far maintained low rates of MRSA. These evolutionary changes have resulted in MRSA continuing to be a major threat to public health. Continuous efforts to understand the changing epidemiology of S. aureus infection in humans and animals are therefore necessary, not only for appropriate antimicrobial treatment and effective infection control but also to monitor the evolution of the species. The group made several consensus decisions with regard to harmonisation of typing methods. A stratified, three-level organisation of testing laboratories was proposed: local; regional; and national. The functions of, and testing methodology used by, each laboratory were defined. The group consensus was to recommend spa and staphylococcal cassette chromosome mec (SCCmec) typing as the preferred methods. Both are informative in defining particular strain characteristics and utilise standardised nomenclatures, making them applicable globally. Effective communication between each of the different levels and between national centres was viewed as being crucial to inform and monitor the molecular epidemiology of MRSA at national and international levels.

Meticillin-resistant Staphylococcus aureus (MRSA): screening and decolonisation.

Meticillin-resistant Staphylococcus aureus (MRSA) infections are of increasing importance to clinicians, public health agencies and governments. Prevention and control strategies must address sources in healthcare settings, the community and livestock. This document presents the conclusions of a European Consensus Conference on the role of screening and decolonisation in the control of MRSA infection. The conference was held in Rome on 5-6 March 2010 and was organised jointly by the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and the International Society of Chemotherapy (ISC). In an environment where MRSA is endemic, universal or targeted screening of patients to detect colonisation was considered to be an essential pillar of any MRSA control programme, along with the option of decolonising carriers dependent on relative risk of infection, either to self or others, in a specific setting. Staff screening may be useful but is problematic as it needs to distinguish between transient carriage and longer-term colonisation. The consequences of identification of MRSA-positive staff may have important effects on morale and the ability to maintain staffing levels. The role of environmental contamination in MRSA infection is unclear, but screening may be helpful as an audit of hygiene procedures. In all situations, screening procedures and decolonisation carry a significant cost burden, the clinical value of which requires careful evaluation. European initiatives designed to provide further information on the cost/benefit value of particular strategies in the control of infection, including those involving MRSA, are in progress.

Relationship between the number of different antibiotics used and the total use of antibiotics in European hospitals.

OBJECTIVES: The aim of this study was to establish whether there was a relationship between the number of antibacterial agents used and total antibiotic use in European hospitals. METHODS: A total of 139 hospitals from 30 countries supplied data on antibiotic use (ATC group J01) for 2001, expressed as the number of defined daily doses per 100 occupied bed-days (DDD/100 BD) and also numbers of different antibiotics used. RESULTS: Participating hospitals used a median of 46 antibiotics in 2001 (range 16-82). The most frequently used antibiotic per hospital accounted for a median of 16.5% (range 7.2-60.9%) of total use and the 10 most frequently used agents accounted for a median of 73.7% (range 53.0-98.5%) of total use. Numbers of antibiotics used varied significantly by European geographical region (Kruskal-Wallis test, P = 0.001). The median total antibiotic use was 49.6 DDD/100 BD. A statistically significant relationship was found between the number of antibiotics used and total antibiotic use (Spearman's rank, r = 0.40 and P < 0.01) for all hospitals. Individual correlations were significant in Western (r = 0.57, P < 0.01) and Southern Europe (r = 0.67, P < 0.01) only. CONCLUSIONS: The quantitative use of antibiotics in European hospitals was highly variable as was the number of different antibiotics used. In the two areas exhibiting highest total use, the greater the number of antibiotics used, the higher the total use of these drugs. Intervention studies are now needed to ascertain whether or not successful antibiotic restriction policies can reduce total antibiotic use and subsequently reduce antibiotic resistance.

Calculation of composite recovery time: a new pharmacodynamic parameter.

A new pharmacodynamic parameter, the composite recovery time (CRT), is described and used to calculate species-specific MIC breakpoints. Moxifloxacin data were used for illustration. This required determination of MICs, kill curves and post-antibiotic sub-MIC effect values. Thirteen test isolates included Staphylococcus aureus, Haemophilus influenzae and Streptococcus pneumoniae. The concentration at which the CRT equals the dosing interval is the minimum effective concentration, and is effectively the breakpoint. The breakpoints were calculated as 2 mg/L for the pneumococci and quinolone-susceptible H. influenzae isolate, 1 mg/L for staphylococci and 0.5 mg/L for Enterobacteriaceae. Calculated pharmacodynamic breakpoints were very similar to traditional published MIC breakpoints.

Identification and characterization of teicoplanin-intermediate Staphylococcus aureus blood culture isolates in NE Scotland.

The study objective was to screen both methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) isolates from blood cultures for reduced susceptibility to vancomycin and teicoplanin. A total of 72 MRSA and 143 MSSA isolates were screened on brain-heart infusion agar containing either 4 mg/L vancomycin or 8 mg/L teicoplanin, using an inoculum of approximately 10(6) organisms. MICs were determined by Etest, broth microdilution and agar incorporation. Isolates were characterized by PFGE, mecA and nuc PCR, transmission electron microscopy (TEM) and analysis of cell proteins (proteomics). Based on British Society for Antimicrobial Chemotherapy (BSAC) breakpoints, seven MRSAs and seven MSSAs were teicoplanin resistant, with MICs of up to 16 and 24 mg/L respectively, but were vancomycin sensitive. Based on higher NCCLS breakpoints, five MRSAs and six MSSAs were teicoplanin intermediate, vancomycin sensitive. All the MRSAs belonged to the EMRSA-16 clone and subdivided into two groups. The MSSAs belonged to five different clones. TEM showed the resistant variants to have slightly thicker cell walls than sensitive variants. Most notably, the resistant variants possessed characteristic dark, granular material concentrated in the middle of the cells, believed to be chromosome. Proteomics showed the resistant variants to overexpress phosphoglycerate kinase. Both MRSA and MSSA with reduced teicoplanin susceptibility may remain vancomycin sensitive by NCCLS and BSAC criteria and it is important to screen clinical isolates of MRSA and MSSA for reduced susceptibility to both agents.

Antimicrobial drug use and methicillin-resistant Staphylococcus aureus, Aberdeen, 1996-2000.

Similar to many hospitals worldwide, Aberdeen Royal Infirmary has had an outbreak of methicillin-resistant Staphylococcus aureus (MRSA). In this setting, the outbreak is attributable to two major clones. The relationships between antimicrobial use and MRSA prevalence were analyzed by time-series analysis. From June 1997 to December 2000, dynamic, temporal relationships were found between monthly %MRSA and previous %MRSA, macrolide use, third-generation cephalosporin use, and fluoroquinolone use. This study suggests that use of antimicrobial drugs to which the MRSA outbreak strains are resistant may be an important factor in perpetuating the outbreak. Moreover, this study confirmed the ecologic effect of antimicrobial drug use (i.e., current antimicrobial use) may have an effect on resistance in future patients. Although these results may not be generalized to other hospitals, they suggest new directions for control of MRSA, which has thus far proved difficult and expensive.