Antimicrobial susceptibility testing in European hospitals: report from the ARPAC study

Variability in contact precautions to control the nosocomial spread of multi-drug resistant organisms in the endemic setting: a multinational cross-sectional survey

Background

Definitions and practices regarding use of contact precautions and isolation to prevent the spread of gram-positive and gram-negative multidrug-resistant organisms (MDRO) are not uniform.

Methods

We conducted an on-site survey during the European Congress on Clinical Microbiology and Infectious Diseases 2014 to assess specific details on contact precaution and implementation barriers.

Results

Attendants from 32 European (EU) and 24 non-EU countries participated (n = 213). In EU-respondents adherence to contact precautions and isolation was high for Methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Enterobacteriaceae, and MDR A. baumannii (84.7, 85.7, and 80%, respectively) whereas only 68% of EU-respondents considered any contact precaution measures for extended-spectrum-beta-lactamase (ESBL) producing non-E. coli. Between 30 and 45% of all EU and non-EU respondents did not require health-care workers (HCW) to wear gowns and gloves at all times when entering the room of a patient in contact isolation. Between 10 and 20% of respondents did not consider any rooming specifications or isolation for gram-positive MDRO and up to 30% of respondents abstain from such interventions in gram-negative MDRO, especially non-E. coli ESBL. Understaffing and lack of sufficient isolation rooms were the most commonly encountered barriers amongst EU and non-EU respondents.

Conclusion

The effectiveness of contact precautions and isolation is difficult to assess due to great variation in components of the specific measures and mixed levels of implementation. The lack of uniform positive effects of contact isolation to prevent transmission may be explained by the variability of interpretation of this term. Indications for contact isolation require a global definition and further sound studies.

Electronic supplementary material

The online version of this article (10.1186/s13756-018-0366-5) contains supplementary material, which is available to authorized users.

Efficient photodynamic therapy against gram-positive and gram-negative bacteria using THPTS, a cationic photosensitizer excited by infrared wavelength

The worldwide rise in the rates of antibiotic resistance of bacteria underlines the need for alternative antibacterial agents. A promising approach to kill antibiotic-resistant bacteria uses light in combination with a photosensitizer to induce a phototoxic reaction. Concentrations of 1, 10 and 100µM of tetrahydroporphyrin-tetratosylat (THPTS) and different incubation times (30, 90 and 180min) were used to measure photodynamic efficiency against two Gram-positive strains of S.aureus (MSSA and MRSA), and two Gram-negative strains of E.coli and P.aeruginosa. We found that phototoxicity of the drug is independent of the antibiotic resistance pattern when incubated in PBS for the investigated strains. Also, an incubation with 100µM THPTS followed by illumination, yielded a 6lg (≥99.999%) decrease in the viable numbers of all bacteria strains tested, indicating that the THPTS drug has a high degree of photodynamic inactivation. We then modulated incubation time, photosensitizer concentration and monitored the effect of serum on the THPTS activity. In doing so, we established the conditions to obtain the strongest bactericidal effect. Our results suggest that this new and highly pure synthetic compound should improve the efficiency of photodynamic therapy against multiresistant bacteria and has a significant potential for clinical applications in the treatment of nosocomial infections.

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.

Antibacterial activities of crude extract of Aloe barbadensis to clinically isolated bacterial pathogens

The antibacterial activity of Aloe barbadensis was tested on clinically isolated bacterial pathogens i.e. Enterococcus bovis, Staphylococcus aureus, Escherichia coli, Proteus vulgaris, Proteus mirabilis, Pseudomonas aeruginosa, Morganella morganii, and Klebsiella pneumoniae causing infection in human being. Ethanolic and aqueous extracts were used for the antibacterial effect, which was measured by the appearance of zone of inhibition. Relatively higher MIC concentrations were obtained for gram negative bacteria E. coli and K. pneumoniae, with ethanol extract; however, no inhibitory effect was noted for aqueous extract. Ethanolic extract possesses great inhibitory activity for gram positive bacteria, E. bovis followed by S. aureus. Among gram negative bacteria, highest inhibitory effect was observed with P. aeruginosa, followed by M. morganii, P. mirabilis, and P. vulgaris, which was significant (p < 0.01) than E. coli and K. pneumoniae. Antimicrobial activity tests of crude extract of A. barbadensis were carried out to validate the use of traditional medicinal herbal and results of this study tend to give credence to the common use of A. barbadensis gel and leaf.

Antimicrobial drug use and resistance in Europe

Routine surveillance data indicate a relation between use and resistance and support interventions designed to reduce antimicrobial consumption at a national level in Europe.

Our study confronts the use of antimicrobial agents in ambulatory care with the resistance trends of 2 major pathogens, Streptococcus pneumoniae and Escherichia coli, in 21 European countries in 2000–2005 and explores whether the notion that antimicrobial drug use determines resistance can be supported by surveillance data at national aggregation levels. The data obtained from the European Surveillance of Antimicrobial Consumption and the European Antimicrobial Resistance Surveillance System suggest that variation of consumption coincides with the occurrence of resistance at the country level. Linear regression analysis showed that the association between antimicrobial drug use and resistance was specific and robust for 2 of 3 compound pathogen combinations, stable over time, but not sensitive enough to explain all of the observed variations. Ecologic studies based on routine surveillance data indicate a relation between use and resistance and support interventions designed to reduce antimicrobial drug consumption at a national level in Europe.

Antibiotic use in 26 departments of internal medicine in 6 general hospitals in Israel: variability and contributing factors

OBJECTIVES

Increased antibiotic consumption is associated with increased bacterial resistance worldwide. We aimed to analyse antibiotic consumption and potential contributory factors in internal medicine departments in Israel.

METHODS

Data (2003-04) from 26 departments in 6 hospitals were retrieved. Defined daily doses (DDD)/100 bed-days were calculated for total antibiotic use and by antibiotic class. Patterns identified were correlated with 15 patients' and departmental variables by univariate and multivariate analyses.

RESULTS

Total antibiotic consumption differed by a factor of 2.3 (115 DDD/100 bed-days to 49.1 DDD/100 bed-days) between the highest and lowest consuming departments. Antibiotic classes differed by a factor of 22.8 for macrolides, a factor of 20 for piperacillin/tazobactam, a factor of 17 for carbapenems, a factor of 13.3 for quinolones, a factor of 9 for vancomycin, a factor of 6.8 for amoxicillin/clavulanate, a factor of 6.6 for aminoglycosides, a factor of 5.3 for penicillins and a factor of 2.8 for cephalosporins. Even among departments within hospitals, there was a difference of up to 1.5-fold for total use and antibiotic class differences ranged between 2.5- and 7.2-fold for third- and fourth-generation cephalosporins, despite similar Charlson scores and other patient variables. In the multivariate analysis, hospital affiliation and rate of 1 day hospitalization were the only significant variables predicting total antibiotic use, contributing 43% and 7.3%, respectively, to the variance. By antibiotic class, controlling for hospital affiliation, patients with neutropenia, lower respiratory tract infections and assisted ventilation were the most common significant contributors, ranging from 3.5% for quinolones to 7.7% for piperacillin/tazobactam.

CONCLUSIONS

Patterns of antibiotic use vary widely among internal medicine departments in Israel, which cannot be explained by objective parameters related either to patients or wards. Ongoing monitoring and guideline formulation are needed to regulate antibiotic prescription.

Screening methods used to determine the anti-microbial properties of Aloe vera inner gel

The emergence of antibiotic resistant bacterial strains is a growing problem and is an important concern for patients, physicians, healthcare managers, and policymakers as it results in poorer health and economic outcomes. This has led to an urgent global call for new antimicrobial drugs, particularly from natural resources. We have been studying the antimicrobial properties of the inner leaf gel component of Aloe barbadensis Miller and have used a number of different, simple in vitro assays to establish a scientific basis for the potential use of Aloe vera on a range of clinically relevant bacteria. The bacteria used include Shigella flexneri, Methicillin-Resistant Staphylococcus aureus (MRSA), Enterobacter cloacae and Enterococcus bovis. In this paper, we compare standard methods recommended by the Clinical and Laboratory Standards Institute (CLSI) with a microtitre assay using a metabolic colour indicator Alamar blue. All the techniques described have shown that Aloe vera has an antimicrobial effect, however, the microtitre assay enables high throughput screening, under similar conditions and is less wasteful of plant material.

The state of play in the battle against antimicrobial resistance: a general practitioner perspective

This article summarizes personal reflections from the perspective of general practice on developments with regard to antibiotic resistance and the containment of antibiotic prescribing during the lifetime of the Specialist Advisory Committee on Antimicrobial Resistance in England. These reflections concern the entry of antibiotics into the food chain, recent extensions of prescribing responsibilities and developments towards improved surveillance and reduced antibiotic prescribing. A large gap remains between the scientific appreciation of the risks from antimicrobial resistance and effective means to measure it and thereby hopefully control it.

Recomendaciones para la selección de antimicrobianos en el estudio de la sensibilidad in vitro con sistemas automáticos y semiautomáticos

The number of clinical microbiology laboratories that have incorporated automatic susceptibility testing devices has increased in recent years. The majority of these systems determine MIC values using microdilution panels or specific cards, with grouping into clinical categories (susceptible, intermediate or resistant) and incorporate expert systems to infer resistance mechanisms. This document presents the recommendations of a group of experts designated by Grupo de Estudio de los Mecanismos de Acción y Resistencia a los Antimicrobianos (GEMARA, Study group on mechanisms of action and resistance to antimicrobial agents) and Mesa Española de Normalización de la Sensibilidad y Resistencia a los Antimicrobianos (MENSURA, Spanish Group for Normalizing Antimicrobial Susceptibility and Antimicrobial Resistance), with the aim of including antimicrobial agents and selecting concentrations for the susceptibility testing panels of automatic systems. The following have been defined: various antimicrobial categories (A: must be included in the study panel; B: inclusion is recommended; and C: inclusion is secondary, but may facilitate interpretative reading of the antibiogram) and groups (0: not used in therapeutics but may facilitate the detection of resistance mechanisms; 1: must be studied and always reported; 2: must be studied and selectively reported; 3: must be studied and reported at a second level; and 4: should be studied in urinary tract pathogens isolated in urine and other specimens). Recommended antimicrobial concentrations are adapted from the breakpoints established by EUCAST, CLSI and MENSURA. This approach will lead to more accurate susceptibility testing results with better detection of resistance mechanisms, and allowing to reach the clinical goal of the antibiogram.

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.