Systematic screening for digestive carriage of extended-spectrum ß-lactamase-producing Enterobacterales (E-ESBL) at hospital readmission among patients with past history of E-ESBL colonization or infection.

BACKGROUND: Extended-spectrum ß-lactamase-producing Enterobacterales (E-ESBL) are commensal multidrug-resistant (MDR) bacteria of the digestive tract whose prevalence has risen sharply worldwide and in Europe over the past two decades. AIM: To assess digestive carriage at hospital readmission of a large cohort of 2509 patients with E-ESBL carriage over a five-year survey; 833 (33%) patients were readmitted at least once. METHODS: A retrospective, single-centre survey conducted at a tertiary care hospital in France. FINDINGS: Among patients with several hospital readmissions (range: 2-13), the proportion of patients still E-ESBL-colonized at hospital readmission, detected by systematic screening for E-ESBL colonization, was >80% within an 18-month period after prior hospitalization with the first E-ESBL isolation. CONCLUSION: There is a need to reconsider the continuation of systematic screening for E-ESBL colonization because of a high rate of patients still colonized at hospital readmission over a long period of time.

Enterobacter cloacae complex outbreak in a neonatal intensive care unit: multifaceted investigations and preventive measures are needed.

We report the investigation to control an Enterobacter cloacae complex outbreak in a neonatal intensive care unit from November 2020 to February 2021. Pulsed-field gel electrophoresis showed that five of eight cases were infected with a clonal strain. Breast pumps, shared among mothers in the unit, could have contributed to the spread of the clonal spread.

Duodenoscopy: an amplifier of cross-transmission during a carbapenemase-producing Enterobacteriaceae outbreak in a gastroenterology pathway.

Carbapenemase-producing Klebsiella pneumoniae (OXA-48 CPE) were identified in five patients who underwent an endoscopy with the same duodenoscope in October 2015. The endoscope was the only epidemiological link between these cases. A transient contamination of the duodenoscope following a failure in the disinfection process may have been the cause of transmission.

New insights on antimicrobial efficacy of copper surfaces in the healthcare environment: a systematic review.

OBJECTIVES: Hospital-acquired infections (HAIs) are a major public health issue. The potential of antimicrobial copper surfaces in reducing HAIs' rates is of interest but remains unclear. We conducted a systematic review of studies assessing the activity of copper surfaces (colony-forming unit (CFU)/surface, both in vitro and in situ) as well as clinical studies. In vitro study protocols were analysed through a tailored checklist developed specifically for this review, in situ studies and non-randomized clinical studies were assessed using the ORION (Outbreak Reports and Intervention studies Of Nosocomial infection) checklist and randomized clinical studies using the CONSORT guidelines. METHODS: The search was conducted using PubMed database with the keywords 'copper' and 'surfaces' and 'healthcare associated infections' or 'antimicrobial'. References from relevant articles, including reviews, were assessed and added when appropriate. Articles were added until 30 August 2016. Overall, 20 articles were selected for review including 10 in vitro, eight in situ and two clinical studies. RESULTS: Copper surfaces were found to have variable antimicrobial activity both in vitro and in situ, although the heterogeneity in the designs and the reporting of the results prevented conclusions from being drawn regarding their spectrum and activity/time compared to controls. Copper effect on HAIs incidence remains unclear because of the limited published data and the lack of robust designs. Most studies have potential conflicts of interest with copper industries. CONCLUSIONS: Copper surfaces have demonstrated an antimicrobial activity but the implications of this activity in healthcare settings are still unclear. No clear effect on healthcare associated infections has been demonstrated yet.

Risk-factors for gastrointestinal colonisation with resistant Enterobacteriaceae among hospitalised patients: a prospective study.

This study assessed the incidence of gastrointestinal colonisation by resistant Enterobacteriaceae among hospitalised patients, and identified risk-factors for ceftazidime and ofloxacin resistance. A prospective cohort study was performed in five wards in a French teaching hospital during a 2-year period. Patients hospitalised for > 48 h were enrolled between 17 April 2000 and 30 April 2002. A rectal swab was taken at admission, then once-weekly and/or on the day of discharge. In total, 933 patients were investigated and 585 amoxycillin-resistant isolates were obtained. Resistance rates for ceftazidime and ofloxacin were 9.4% and 4.8%, respectively. Multivariate analysis indicated that previous hospitalisation (p < 0.004) and exposure to amoxycillin-clavulanate (p < 0.003) and ceftriaxone (p < 0.002) were associated significantly with ceftazidime resistance. Hospitalisation in the urology ward (p < 0.02) and previous exposure to fluoroquinolones (p < 0.01) were the two independent risk-factors associated with ofloxacin resistance. The results of the study confirmed that antibiotic use selected resistant Enterobacteriaceae from the gut flora. Resistance was observed mostly in patients with previous antibiotic exposure and previous hospitalisation in wards with a high antibiotic selection pressure.

Role of hospital stay and antibiotic use on Pseudomonas aeruginosa gastrointestinal colonization in hospitalized patients.

The prospective cohort study presented here assessed the risk factors associated with Pseudomonas aeruginosa gastrointestinal colonization (PAGIC) in 933 patients hospitalized in five different wards in a French university hospital. A total of 195 patients were colonized. By logistic regression, hospitalization in an intensive care unit and length of hospital stay were independent risk factors. A significant association was observed between fluoroquinolone use and PAGIC caused by an ofloxacin-resistant strain (p < 0.0001), imipenem use and PAGIC caused by an imipenem-resistant strain (p < 0.0002) and ceftazidime use and PAGIC caused by a ceftazidime-resistant strain (p < 0.02). The ecological impact of antibiotic use is of great clinical relevance and clinicians should consider antimicrobial resistance in order to limit the development and dissemination of resistant microorganisms.

Isolation of Legionella oakridgensis from two patients with pleural effusion living in the same geographical area.

Two cases of Legionnaire's disease caused by Legionella oakridgensis were diagnosed at the university hospital in Nantes, France. The two patients' isolates were identified by means of phenotyping and genotyping methods. Epidemiological investigations concluded that the first case was hospital acquired while the second case was considered community acquired.

Two epidemiologically related cases of Rahnella aquatilis bacteremia.

Rahnella aquatilis was isolated from the blood cultures of two patients who were in different units of the same hospital. Both isolates were susceptible to aminoglycosides, fluoroquinolones, cotrimoxazole, piperacillin, third generation cephalosporins and amoxicillin-clavulanate, but resistant to amoxicillin, ticarcillin, and first generation cephalosporins. The synergistic activity of amoxicillin and clavulanic acid suggested the presence of a beta-lactamase, confirmed by a positive nitrocefin test and by analytical isoelectric focusing. Pulsed-field gel electrophoresis and ribotyping with the pKK3535 probe showed that the isolates shared the same banding pattern. The results of an epidemiological study suggested that an in-house total parenteral nutrition solution might be the source of this unusual gram-negative rod.

Methicillin-resistant Staphylococcus aureus control in hospitals: the French experience. Association des Pays de la Loire pour l'Eviction des Infections Nosocomiales.

The first cases of isolation of Staphylococcus aureus resistant to methicillin in France were published in 1962. However, until recently, very few epidemiological studies or attempts to control the epidemic have been done in France. In this article, we present the results of a prospective study performed during a 3-month period in 27 hospitals of the Région des Pays de la Loire. Among the 94,605 hospitalized patients included in the study, 0.45% (427) developed methicillin-resistant Staphylococcus aureus (MRSA) infections, the incidence rate ranging from 0% to 1.2%. Thirty-four percent of MRSA-infected patients were 80 years old or older, 30% had been transferred from another service and 19% from another hospital, 56% were hospitalized at least once during the previous year, MRSA had been isolated at least once previously in 18% of MRSA-infected patients, 19% died, 16% were transferred to another service and 11% to another hospital, and only 32% were discharged to their homes. A poor compliance to contact isolation precautions was observed in all hospitals: 46% of MRSA-infected patients were hospitalized in a private room; gloves, masks, and gowns were worn for the care of 63.4%, 14%, and 42.5% of MRSA-infected patients, respectively; and handwashing was feasible in the rooms of 52% of the patients.

Pharmacokinetics, toxicity, and efficacy of liposomal capreomycin in disseminated Mycobacterium avium beige mouse model.

Capreomycin was incorporated into multilamellar vesicles of pure dipalmitoylphosphatidylcholine. The pharmacokinetics and nephrotoxicity of capreomycin in the free and liposomal forms were studied in normal mice. The efficacies of the two forms were evaluated by using the Mycobacterium avium complex beige mouse model. Approximately 10(7) viable M. avium cells were injected intravenously. Seven days later, treatment with either liposomal or free capreomycin at 60 or 120 mg/kg of body weight was administered daily for 5 days. Mice were sacrificed 5 days after the end of treatment, and the viable bacteria in liver, spleen, lungs, and blood were counted. After 5 days of treatment with dosages of 60 or 120 mg/kg/day, the level of blood urea nitrogen increased in the group treated with free capreomycin but not in the group treated with liposomal capreomycin. After intravenous injection of 120 mg/kg, liposomes enhanced the diffusion of capreomycin in the spleen, lungs, and kidneys and increased the half-life in serum. The 120-mg/kg dose of liposomal capreomycin significantly reduced the number of viable mycobacteria in the liver, spleen, and blood compared with those in the controls. Although these results are promising, further studies are needed to assess the efficacy of liposomal capreomycin for the treatment of M. avium complex infections.

Identification of factors affecting in vivo aminoglycoside activity in an experimental model of gram-negative endocarditis.

Aminoglycoside bactericidal activity during the first 24 h of treatment probably is a determining parameter in the prognosis of severe gram-negative infections in immunocompromised patients. To identify the predictive factors involved in the definition of the best therapeutic regimen for Enterobacter cloacae and Serratia marcescens infections, we studied different gentamicin, tobramycin, and amikacin regimens by using an experimental model of rabbit endocarditis. Two factors appear to play an important role in predicting in vivo efficacy: (i) the level of in vivo bactericidal activity, which can differ widely from one aminoglycoside to another for the same bacterial strain and from one strain to another of the same species, and (ii) the critical serum drug concentration (CSC, in milligrams per liter), defined as the lowest serum antibiotic concentration capable of producing a significant CFU reduction (P less than 0.05) in endocarditis vegetations 24 h after the beginning of a continuous infusion. Stepwise regression analysis showed that for gentamicin and S. marcescens, the area under the concentration-time curve above the CSC and then the time above the CSC are the determining parameters for efficacy (R = 0.69; F = 13.5; P = 0.001), whereas for amikacin and S. marcescens, the time above the CSC and then the area under the concentration-time curve above the CSC predict efficacy (R = 0.74; F = 24.0; P = 0.0001). The lowest CSC is that of amikacin (about 8 mg/liter); those of gentamicin and tobramycin are about 15 mg/liter. In severe S. marcescens infections, intermittent amikacin dosing offers excellent bactericidal activity within the first 24 h.

Impact of dosage schedule on the efficacy of gentamicin, tobramycin, or amikacin in an experimental model of Serratia marcescens endocarditis: in vitro-in vivo correlation.

Aminoglycosides are usually considered to be concentration-dependent antibiotics and to have similar pharmacodynamic and pharmacokinetic properties. To verify the equivalent activity of the aminoglycosides on a susceptible strain, we tested the killing rate of three aminoglycosides (gentamicin, tobramycin, and amikacin) on one strain of Serratia marcescens both in vitro and in vivo by using a rabbit model of left-ventricle endocarditis. Despite, similar MICs, the time-kill curve of gentamicin was consistently better than those of amikacin and tobramycin, whatever the concentration of each antibiotic used (1, 2, 4, 8, 16, or 32 mg/liter), after a 5-h incubation. The in vivo bacterial reduction in the vegetations was measured 24 h after administration of an intravenous 48-mg/kg bolus of each antibiotic or at the end of a 24-h continuous intravenous infusion of the same dose. Gentamicin was significantly more effective when administered as a bolus than when administered as a continuous infusion (2.8 +/- 0.2 versus 6.4 +/- 1.5 log10 CFU/g of vegetation, respectively; P less than 0.01), whereas amikacin was more effective as a continuous infusion than as a bolus injection (3.6 +/- 2.0 versus 7.5 +/- 1.3 log10 CFU/g of vegetation, respectively; P less than 0.01). Tobramycin was not very effective, whatever the dosage tested (approximately 6.5 to 7 log10 CFU/g). These results suggest that concentration-dependent bactericidal activities, both in vitro and in vivo, may vary greatly among aminoglycosides despite similar MICs.