Surveillance of methicillin-resistant Staphylococcus aureus (MRSA) in acute care hospitals. Results of the VINCat Program (2008–2010)

Bacteremia associated with pressure ulcers: a prospective cohort study

The objective of this study is to evaluate the clinical and microbiological characteristics of bacteremia associated with pressure ulcers (BAPU) and factors associated with mortality. This study was a prospective observational cohort study of patients with BAPU at a teaching hospital between January 1984 and December 2015. Fifty-six episodes were included. The incidence of BAPU decreased from 2.78 cases per 10,000 hospital discharges in the period from 1984 to 1999 to 1.05 cases per 10,000 hospital discharges in the period from 2000 to 2015 (p < 0.001). In 20 cases (35.7%), the bacteremia was hospital-acquired, since it occurred more than 48 h after the hospital admission. The most frequent microorganisms isolated in blood culture were Staphylococcus aureus, Proteus spp., and Bacteroides spp. The bacteremia was polymicrobial in 14 cases (25.0%). Overall mortality was observed in 23 episodes (41.1%). The risk factors independently associated with mortality were hospital-acquired bacteremia (odds ratio [OR] 5.51, 95% confidence interval [95%CI] 1.24-24.40), polymicrobial bacteremia (OR 6.88, 95%CI 1.22-38.89), and serum albumin <23 g/L (OR 8.00, 95%CI 1.73-37.01). BAPU is an uncommon complication of pressure ulcers and is mainly caused by S. aureus, Proteus spp., and Bacteroides spp. In our hospital, the incidence of BAPU has declined in recent years, coinciding with the implementation of a multidisciplinary team aimed at preventing and treating chronic ulcers. Mortality rate is high, and hospital-acquired bacteremia, polymicrobial bacteremia, and serum albumin < 23 g/L are associated with increased mortality.

[Survey of methicillin-resistant Staphylococcus aureus control measures in hospitals participating in the VINCat program]

INTRODUCTION

VINCat is a nosocomial infection surveillance program in hospitals in Catalonia. The aim of the study was to determine the surveillance and control measures of methicillin-resistant Staphylococcus aureus (MRSA) in these centres.

METHODS

An e-mail survey was carried out from January to March 2013 with questions related to the characteristics of the hospitals and their control measures for MRSA.

RESULTS

A response was received from 53 hospitals (>500 beds: 7; 200-500 beds: 14;<200 beds: 32; had ICU: 29). Computer alert of readmissions was available in 63%. There was active surveillance of patients admitted from another hospital (46.2%) or a long-term-care centre (55.8%), both being significantly more common measures in hospitals with a rate of MRSA≤22% (global median). Compliance with hand hygiene was observed in 77.4% of the centres, and was greater than 50% in 69.7% of them. All hospitals had contact precautions, although 62.3% did not have exclusive frequently used clinical material in bedrooms. The room cleaning was performed more frequently in 54.7% of hospitals, and 67.9% of them had programs for the appropriate use of antibiotics.

CONCLUSIONS

This study provides information on the implementation of measures to prevent MRSA in hospitals participating in the VINCat program. Most of the centres have an MRSA protocol, however compliance with it should be improved, especially in areas such as active detection on admission in patients at risk, hand hygiene adherence, cleaning frequency and optimising the use of antibiotics.

Relationship between consumption of MRSA-active antibiotics and burden of MRSA in acute care hospitals in Catalonia, Spain

OBJECTIVES

To analyse the possible relationship between consumption of old and new MRSA-active antibiotics and burden of MRSA in acute care hospitals in Catalonia during the period 2007-12.

METHODS

Fifty-four hospitals participating in the VINCat Programme were included. Proportion of MRSA (resistant isolates of Staphylococcus aureus per 100 isolates of S. aureus tested), incidence of new cases of infection [new cases of MRSA per 1000 occupied bed-days (OBD)] and incidence of cases of bacteraemia (MRSA bacteraemia cases per 1000 OBD) were determined to estimate the annual MRSA burden. Antibiotic consumption was calculated in DDD/100 OBD. Cost was expressed in euros/100 OBD.

RESULTS

MRSA rates remained stable over the study period, with the proportion of MRSA ranging from 20% to 22.82% in 2007 and 2012, respectively (P=0.864). Consumption of old MRSA-active antibiotics (vancomycin and teicoplanin) did not change significantly, with values from 1.51 to 2.07 DDD/100 OBD (P=0.693). Consumption of new MRSA-active antibiotics (linezolid and daptomycin) increased significantly, with values rising from 0.24 to 1.49 DDD/100 OBD (P<0.001). Cost increased by almost 200%.

CONCLUSIONS

A widespread and steady increase in consumption of new MRSA-active antibiotics was observed among acute care hospitals in Catalonia, in spite of a stable MRSA burden. At the same time, consumption of old drugs remained stable. Such trends resulted in a significant increase in cost. Our findings suggest that factors other than the proportion of methicillin resistance among S. aureus may influence the use of old and new MRSA-active antibiotics in the clinical setting.

European perspective and update on the management of nosocomial pneumonia due to methicillin-resistant Staphylococcus aureus after more than 10 years of experience with linezolid

Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of antimicrobial-resistant hospital-acquired infections worldwide and remains a public health priority in Europe. Nosocomial pneumonia (NP) involving MRSA often affects patients in intensive care units with substantial morbidity, mortality and associated costs. A guideline-based approach to empirical treatment with an antibacterial agent active against MRSA can improve the outcome of patients with MRSA NP, including those with ventilator-associated pneumonia. New methods may allow more rapid or sensitive diagnosis of NP or microbiological confirmation in patients with MRSA NP, allowing early de-escalation of treatment once the pathogen is known. In Europe, available antibacterial agents for the treatment of MRSA NP include the glycopeptides (vancomycin and teicoplanin) and linezolid (available as an intravenous or oral treatment). Vancomycin has remained a standard of care in many European hospitals; however, there is evidence that it may be a suboptimal therapeutic option in critically ill patients with NP because of concerns about its limited intrapulmonary penetration, increased nephrotoxicity with higher doses, as well as the emergence of resistant strains that may result in increased clinical failure. Linezolid has demonstrated high penetration into the epithelial lining fluid of patients with ventilator-associated pneumonia and shown statistically superior clinical efficacy versus vancomycin in the treatment of MRSA NP in a phase IV, randomized, controlled study. This review focuses on the disease burden and clinical management of MRSA NP, and the use of linezolid after more than 10 years of clinical experience.

[Validation of the structure and resources of nosocomial infection control team in hospitals ascribed to VINCat program in Catalonia, Spain]

The main objective of this study was to validate the structure of the infection control team (ICT) in the hospitals adhered to VINCat program and secondary objective was to establish the consistency of resources of each center with the requirements established by the program. Qualitative research consisting of an ethnographic study using participant observation during the years 2008-2010. The centers were stratified in three groups by complexity and beds. The instrument was a semistructured interview to members of the ICT. The transcription of the interview was sent to informants for validation. In November 2010 a questionnaire regarding human resources and number hours dedicated to the ICT was sent. During 2008-2010, 65 centers had been adhered to VINCat program. In 2010, the ICT of Group I hospitals had a mean of two physician, one in full-time and one nurse for every 230 beds. In Group II, one physician part-time and one nurse per 180 beds and in Group III a physician and a nurse for every 98 beds, both part-time. In 2010, all hospitals had a structured ICT, an operative infection committee, and a hospital member representing the center at the program as well as enough electronic resources. The hospitals participating in the program have now VINCat an adequate surveillance structure and meet the minimum technical and human resources required to provide high-quality data. However human resources are not guaranteed.

Resistance mechanisms and epidemiology of multiresistant pathogens in Europe and efficacy of tigecycline in observational studies

OBJECTIVES

Antimicrobial drug resistance is a growing problem in Europe and, even with differences in epidemiology, it is of great concern. The treatment of complicated skin and soft-tissue infections (cSSTIs) and complicated intra-abdominal infections (cIAIs) is hindered further by pathogens that are resistant to methicillin, carbapenems, third-generation cephalosporins and glycopeptides.

PATIENTS AND METHODS

An analysis of the microbiological results from five European observational studies (July 2006 to October 2011) evaluating the efficacy of tigecycline (prescribed as monotherapy or in combination with other antibacterials) for the treatment of cSSTI and cIAI is presented.

RESULTS

In total, 213 cSSTI and 623 cIAI patients were included; 34.4% and 56.6%, respectively, were critically ill in intensive care units. At baseline, at least one pathogen was isolated in 167 (78.4%) cSSTI and 464 (74.5%) cIAI patients, and 32.9% and 49.1% of infections were polymicrobial. In cSSTI, Staphylococcus aureus and Escherichia coli (52.7% and 18.0%, respectively) were the most frequently isolated pathogens, whereas in cIAI most infections were due to E. coli (41.8%), Enterococcus faecium (40.1%) and Enterococcus faecalis (21.1%). Clinical response was observed in >80% of patients with E. coli in both cIAI and cSSTI. In cSSTI patients, the clinical response rate to S. aureus was 80.8%. For cIAI, 77.4% of E. faecium and 79.5% of E. faecalis patients responded to treatment.

CONCLUSIONS

Tigecycline when given alone or in combination with other antibacterials appeared to be efficacious against multiple pathogens, affirming its role in real-life clinical practice as a broad-spectrum antibacterial for the treatment of patients with cSSTI and cIAI, including the critically ill, across Europe.

Modulators of antibiotic activity from Ipomoea murucoides

Reinvestigation of the CHCl3-soluble extract from the flowers of Ipomoea murucoides, through preparative-scale recycling HPLC, yielded three pentasaccharides of 11-hydroxyhexadecanoic acid, murucoidins XVII-XIX, in addition to the known murucoidin III and V, all of which were characterized by NMR spectroscopy and mass spectrometry. These compounds were found to be macrolactones of the known pentasaccharides simonic acid B and operculinic acid A. The acylating groups corresponded to acetic, (2S)-methyl-butyric, (E)-cinnamic and octanoic acids. The esterification sites were established at the C-2 of the second rhamnose and C-3 and C-4 of the third rhamnose. The aglycone lactonization was placed at C-2 or C-3 of the first rhamnose. Bioassays for modulation of antibiotic activity were performed against multidrug-resistant strains of Staphylococcus aureus, Escherichia coli Rosetta-gami, and two nosocomial pathogens: Salmonella enterica sv. Typhi and Shigella flexneri. The tested glycolipids did not act as cytotoxic (IC50>4 μg/mL) nor as antimicrobial (MIC>128 μg/mL) agents. However, they exerted a potentiation effect on clinically useful antibiotics against the tested bacteria by increasing their antibiotic susceptibility up to four-fold at concentrations of 25 μg/mL.

Continuous increase of the antimicrobial resistance among gram-negative pathogens causing bacteremia: a nationwide surveillance study by the Korean Network for Study on Infectious Diseases (KONSID)

Antimicrobial susceptibility data for all microorganisms isolated from blood culture were collected from 13 institutions in Korea from June to September 2011. Data were compared with our previous studies performed during 2006-2007 and 2008. The prevalence of MRSA in 2011 has rebounded to 63.7% after a slight decrease in 2008. Vancomycin-resistant Enterococcus faecium declined to 24.1%. The resistance rates of Acinetobacter baumannii to imipenem and meropenem increased from 25.4% and 28.8% to 55.4% and 37.5%, respectively. Ciprofloxacin resistance of Escherichia coli has increased from 23.9% to 30.8%. The resistance rate of Klebsiella pneumoniae to ciprofloxacin has increased from 17.7% to 26.5%. Extended spectrum beta-lactamase-producing E. coli and K. pneumoniae have also seen increased levels of resistance, from 8.6% to 18.4% and 13.6% to 28.5%, respectively. An overall increase in antimicrobial resistance among gram-negative pathogens has been observed. Continued surveillance and intervention to slow the propagation of resistance are necessary.