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Objective Short-course aminoglycosides as adjunctive empirical therapy to β-lactams in patients with a clinical suspicion of sepsis are used to broaden antibiotic susceptibility coverage and to enhance bacterial killing. We quantified the impact of this approach on 30-day mortality in a subset of sepsis patients with a Gram-negative bloodstream infection. Methods From a prospective cohort study conducted in seven hospitals in the Netherlands between June 2013 and November 2015, we selected all patients with Gram-negative bloodstream infection (GN-BSI). Short-course aminoglycoside therapy was defined as tobramycin, gentamicin or amikacin initiated within a 48-hour time window around blood-culture obtainment, and prescribed for a maximum of 2 days. The outcome of interest was 30-day all-cause mortality. Confounders were selected a priori for adjustment using a propensity score analysis with inverse probability weighting. Results A total of 626 individuals with GN-BSI who received β-lactams were included; 156 (24.9%) also received aminoglycosides for a median of 1 day. Patients receiving aminoglycosides more often had septic shock (31/156, 19.9% versus 34/470, 7.2%) and had an eight-fold lower risk of inappropriate treatment (3/156, 1.9% versus 69/470, 14.7%). Thirty-day mortality was 17.3% (27/156) and 13.6% (64/470) for patients receiving and not receiving aminoglycosides, respectively; yielding crude and adjusted odds ratios for 30-day mortality for patients treated with aminoglycosides of 1.33 (95% CI 0.80–2.15) and 1.57 (0.84–2.93), respectively. Conclusions Short-course adjunctive aminoglycoside treatment as part of empirical therapy with β-lactam antibiotics in patients with GN-BSI did not result in improved outcomes, despite better antibiotic coverage of pathogens.

Introduction The human gut microbiota is an important reservoir of ESBL-producing Escherichia coli (ESBL-Ec). Community surveillance studies of ESBL-Ec to monitor circulating clones and ESBL genes are logistically challenging and costly. Objectives To evaluate if isolates obtained in routine clinical practice can be used as an alternative to monitor the distribution of clones and ESBL genes circulating in the community. Methods WGS was performed on 451 Dutch ESBL-Ec isolates (2014–17), including 162 community faeces and 289 urine and blood isolates. We compared proportions of 10 most frequently identified STs, PopPUNK-based sequence clusters (SCs) and ESBL gene subtypes and the degree of similarity using Czekanowski’s proportional similarity index (PSI). Results Nine out of 10 most prevalent STs and SCs and 8/10 most prevalent ESBL genes in clinical ESBL-Ec were also the most common types in community faeces. The proportions of ST131 (39% versus 23%) and SC131 (40% versus 25%) were higher in clinical isolates than in community faeces (P

The increase in Highly Resistant Micro-Organisms (HRMO) in hospitals and nursing homes requires an intensification of infection prevention measures. This paper describes a new, standardised approach to infection prevention and monitoring of antibiotic use.Cross-sectional, observational study.The Infection RIsk Scan (IRIS) measures a number of objectifiable variables in the field of infection prevention, including the dissemination of HRMO, the use of antibiotics and indwelling medical devices, environmental contamination, hand hygiene and personal hygiene of healthcare workers, and various infection control preconditions. The scan converts the measurements into a risk profile and an improvement chart, a graphic presentation that is easy to understand for care professionals, managers and patients. Based on the results, targeted improvements can be made by a department or institution, and a quality cycle can be started in which the scans are repeated.The IRIS has been successfully applied in 5 hospital departments, a rehabilitation clinic and 19 nursing homes. In the hospital departments, 3 IRIS cycles resulted in a significant improvement in hand hygiene compliance (43% to 66%, p0.001) and a significant reduction in environmental contamination. In one nursing home, the IRIS resulted in a previously undetected outbreak of HRMO being discovered.The IRIS method makes it possible to compare departments and institutions and can therefore provide an impetus for standardization of measurements of risks and results in the field of infection prevention, antibiotic use and resistance.

Background The prophylactic application of antimicrobials that are active against Staphylococcus aureus can prevent infections. However, implementation in clinical practice is limited. We have reviewed antimicrobial approaches for the prevention of S. aureus infections. Methods We searched the Cochrane Central Register of Controlled Trials, PubMed/MEDLINE and EMBASE databases and trial registries using synonyms for S. aureus, infections and prevention as search terms. We included randomized controlled trials and systematic reviews only. Results Most studies were conducted with mupirocin. Mupirocin is effective in preventing S. aureus infections in patients receiving dialysis treatment and in surgical patients, particularly if the patients are carriers of S. aureus. The combination of mupirocin and chlorhexidine, but not chlorhexidine alone, is also effective against S. aureus infections. So far, vaccines have not proven successful in protecting against S. aureus infections. Regarding prophylactic povidone–iodine and systemic antibiotics, there is limited evidence supporting their effectiveness against S. aureus infections. Antimicrobial honey has not been proven to be more effective or non-inferior to mupirocin in protecting against S. aureus infections. Conclusions The current evidence supports the use of mupirocin as prophylaxis for preventing infections with S. aureus, particularly in carriers and in the surgical setting or in patients receiving dialysis treatment. Other antimicrobial agents have not been sufficiently proven to be effective so far, or have been proven ineffective. New trials with vaccines and anti-staphylococcal peptides are currently underway and may lead to new preventive strategies in the future.

Correct detection of extended-spectrum beta-lactamases (ESBLs) is crucial for infection control and antibiotic choice. We performed a study to determine the cost-effectiveness of phenotypical testing, which can be inaccurate, and genotypical tests, which are considered to be more reliable but also more expensive. All patients that had been in isolation in the Amphia hospital because of the detection of ESBL according to the ESBL Etest were included in the survey. All strains were retested using the double disk confirmation test (DDCT) and a genotypical method. This was a commercially available microarray (Check-Points). Discordant results were confirmed by PCR and sequencing. In total 174 patients were included. In 24 of 174 (14%) patients, ESBL carriage could not be confirmed with the microarray. This was verified with PCR and sequencing. The mean duration of isolation was 15 days, adding up to a total number of isolation days of 2571. False-positive results according to the microarray resulted in a total of 279 days of unnecessary isolation for the Etest and 151 days for the DDCT. Using Etest to detect the presence of ESBL results in a false-positive outcome in 14% of the cases. This results in unnecessary isolation of patients, which can be omitted by using a genotypic method.

Objectives.The objectives of this study were to determine the incidence density and the occurrence of horizontal spread of highly resistant gram-negative rods (HR-GNRs) in Dutch hospitals. The factors that influence these outcome measures were also investigated.Methods.All patients with HR-GNRs, as determined by sample testing, who were hospitalized in 1 of 18 hospitals during a 6-month period (April through October 2007) were included in this study. For all available isolates, the species was identified, susceptibility was determined (including the presence of extended-spectrumβ-lactamases [ESBLs]), and molecular typing was performed. On the basis of a combination of species identification, molecular typing, and epidemiological data, the occurrence of nosocomial transmission was determined.Results.The mean incidence density of patients with HR-GNRs was 55 per 100,000 patient-days (cumulative incidence, 39 per 10,000 patients admitted). A facility being a university hospital was a statistically significant (P= .03) independent determinant of a higher incidence of patients with HR-GNRs. The majority of HR-GNR isolates were ESBL producers. The adjusted transmission index—the ratio between secondary and primary cases—in the participating hospitals ranged from 0.0 to 0.2. The overall adjusted transmission index of HR-GNRs was 0.07. No determinants for a higher transmission index were identified.Discussion.The nosocomial transmission rate of HR-GNRs was relatively low in all hospitals where well-established transmission-based precautions were used. The incidence density of patients with HR-GNRs was higher in university hospitals, probably due to the patient population and the complexity of the care provided.

During a one-day workshop experienced infection control practitioners (ICPs) and medical microbiologists debated how much time was needed for the delivery of infection control activities in a model hospital. They agreed a standard of one full-time equivalent (FTE) ICP per 178 hospital beds and one FTE medical microbiologist per 806 hospital beds. This is 40% and 24% more than the usual standard, respectively. Now that official numbers of hospital beds have become an inadequate parameter for work delivered by hospitals, a new standard is proposed, with the number of admissions as the denominator. This is one FTE ICP per 5000 admissions and one medical microbiologist or epidemiologist per 25000 admissions.

We describe an outbreak of Klebsiella pneurnonine carbapenemase (KPC)-producing Klebsiella pneumoniae (KPC-KP) ST258 that occurred in two institutions (a hospital and a nursing home) in the Netherlands between July and December 2013. In total, six patients were found to be positive for KPC-KP. All isolates were resistant to colistin and exhibited reduced susceptibility to gentamicin and tigecycline. In all settings, extensive environmental contamination was found. Whole genome sequencing revealed the presence of biaKpc_2 and blaspfv_12 genes, as well as the close relatedness of patient and environmental isolates. In the hospital setting, one transmission was detected, despite contact precautions. After upgrading to strict isolation, no further spread was found. After the transfer of the index patient to a nursing home in the same region, four further transmissions occurred. The outbreak in the nursing home was controlled by transfeiring all KPC-KP-positive residents to a separate location outside the nursing home, where a dedicated nursing team cared for patients. This outbreak illustrates that the spread of pan-resistant Enterobacteriaceae can be controlled, but may be difficult, particularly in long-term care facilities. It, therefore, poses a major threat to patient safety. Clear guidelines to control reservoirs in and outside the hospitals are urgently needed.

This review summarizes the clinically relevant aspects of nasal carriage of Staphylococcus aureus. The epidemiology, associated risk, and the effects of eradication are discussed. The main conclusions are that nasal carriage of S. aureus is a well-defined risk factor for subsequent infection in nearly all categories of hospitalized patients that have been studied. However, studies that have been performed to evaluate the effect of eradication of carriage using mupirocin nasal ointment have been inconclusive so far in most subgroups. Only in patients on hemodialysis or chronic ambulatory peritoneal dialysis (CAPD) was a significant reduction of the infection rate found. But prolonged treatment in these groups carries a risk for the development of resistance. In surgical patients two randomized studies have found an effect on the surgical site infection rate in carriers that, when those studies are combined, was close to being statistically significant (p = 0.06). In non-surgical patients a significant delay in the onset of infection was found but the overall infection rate was not significantly different. When the results of all well-designed studies that have been performed are combined, a significant reduction of the nosocomial S. aureus infections in carriers is found (approximately 50% lower). Future studies should focus on treating carriers only and consider other treatment regimens.

The objective of this study was to compare four procedures for Chlamydia pneumoniae DNA extraction from vascular tissue. The NucliSens Kit, the QIAamp tissue DNA MiniKit, buffer—saturated phenol and the Geneclean II Kit were evaluated, based on the yield of recovered DNA, using PCR to detect C. pneumoniae in vascular tissue. The QIAamp tissue procedure had the highest detection level (0.004 inclusion—forming units/sample). All methods, except NucliSens (70 min), had a short handling time (30-40 min). Costs varied from 0.5 to 3.2 Euro.

The objective of this study was to determine whether use of mupirocin nasal ointment for perioperative eradication of Staphylococcus aureus nasal carriage is effective in preventing the development of surgical site infections (SSIs). A randomized, double-blind, placebo-controlled design was used. Either mupirocin or placebo nasal ointment was applied twice daily to 614 assessable patients from the day of admission to the hospital until the day of surgery. A total of 315 and 299 patients were randomized to receive mupirocin and placebo, respectively. Eradication of nasal carriage was significantly more effective in the mupirocin group (eradication rate, 83.5% versus 27.8%). In the mupirocin group, the rate of endogenous S. aureus infections was 5 times lower than in the placebo group (0.3% and 1.7%, respectively; relative risk, 0.19; 95% confidence interval, 0.02-1.62). Mupirocin nasal ointment did not reduce the SSI rate (by S. aureus) or the duration of hospital stay.

Objective To quantify the incidence of intensive care unit (ICU)-acquired pneumonia caused by Staphylococcus aureus ( S. aureus ) and its association with S. aureus colonization at ICU admission. Methods This was a post-hoc analysis of two cohort studies in critically ill patients. The primary outcome was the incidence of microbiologically confirmed S. aureus ICU-acquired pneumonia. Incidences of S. aureus ICU pneumonia and associations with S. aureus colonization at ICU admission were determined using competing risks analyses. In all ICUs, patients were screened for respiratory tract S. aureus carriage on admission as part of infection control policies. Pooling of data was not deemed possible because of heterogeneity in baseline differences in patient population. Results The two cohort studies contained data of 9156 ICU patients. The average carriage rate of S. aureus among screened patients was 12.7%. In total, 1185 (12.9%) patients developed ICU pneumonia. Incidences of S. aureus ICU pneumonia were 1.33% and 1.08% in cohorts 1 and 2, respectively. After accounting for competing events, the adjusted subdistribution hazard ratio (SHR) of S. aureus colonization at admission for developing S. aureus ICU pneumonia was 9.55 (95% CI 5.31-17.18) in cohort 1 and 14.54 (95% CI 7.24-29.21) in cohort 2. Conclusion The overall cumulative incidence of S. aureus ICU pneumonia in these ICUs was low. Patients colonized with S. aureus at ICU admission had an up to 15 times increased risk for developing this outcome compared with non-colonized patients.

Lung abscesses as a complication of pelvic inflammatory disease (PID) caused by an intrauterine device (IUD) have been described previously but are rare. Geddes et al. reported on a 31-year old woman with an copper IUD who developed septicemia with lung abscesses and encephalopathy caused by genital tract infection with Staphylococcus aureus. A vaginal swab and culture from the coil showed a similar antibiogram to that of the S. aureus cultured from the blood [1]. Systemic infection through the hematogenic spread of a microorganism caused by an IUD was previously described, with Actinomyces as the infectious organism [2, 3]. Multiple hepatic abscesses caused by Streptococcus milleri in association with an intrauterine device have also been described [4]. We report a case of a patient with multiple lung abscesses secondary to a uterine empyema caused by an intrauterine device with S. milleri as the causative agent. An otherwise healthy, 29-year old woman visited the emergency room of our hospital with complaints of dyspnea and chest pain. The week before presentation she had flu-like symptoms with fever, a nonproductive cough and myalgia. Since then she experienced shortness of breath, Fig. 3 Computed tomography of the abdomen showing an empyema in the cavum uteri Figs. 1, 2 Computed tomography of the thorax showing consolidations in the lung parenchyma with some cavitation, leading to a suspicion of abscesses

The aim of this study was to quantify the value of clinical predictors available in the emergency department (ED) in predicting Streptococcus pneumoniae as the cause of community-acquired pneumonia (CAP). A prospective, observational, cohort study of patients with CAP presenting in the ED was performed. Pneumococcal aetiology of CAP was based on either bacteraemia, or S. pneumoniae being cultured from sputum, or urinary immunochromatographic assay positivity, or positivity of a novel serotype-specific urinary antigen detection test. Multivariate logistic regression was used to identify independent predictors and various cut-off values of probability scores were used to evaluate the usefulness of the model. Three hundred and twenty-eight (31.0%) of 1057 patients with CAP had pneumococcal CAP. Nine independent predictors for pneumococcal pneumonia were identified, but the clinical utility of this prediction model was disappointing, because of low positive predictive values or a small yield. Clinical criteria have insufficient diagnostic capacity to predict pneumococcal CAP. Rapid antigen detection tests are needed to diagnose S. pneumoniae at the time of hospital admission.

Diagnosis of Legionnaires’ disease (LD) in patients with pneumonia is based on phenotypic (culture, serologic testing, antigen detection in urine) and genotypic PCR methods. This chapter assesses the sensitivity and specificity of Legionella DNA detection using PCR on serum samples from patients with proven LD and patients with infections other than Legionella. Serum samples from two healthy volunteers were included as negative controls after every four samples. One patient was admitted to the emergency department of our hospital with proven LD caused by Legionella pneumophila serogroup 1 (urinary antigen test positive, culture positive, and sputum PCR positive). From this patient, consecutive serum samples were collected for Legionella-specific, real-time PCR. The results of PCR showed an increase in Ct values (corresponding with a logarithmic decrease of bacterial DNA) in the course of time and were found to mirror the clinical condition of the patient and c-reactive protein values during the acute stage of infection. Serologic methods to diagnose L. pneumophila infections are highly sensitive, but their utility is generally limited to epidemiologic studies due to the time lag needed to detect seroconversion. The advantages of PCR for the detection of L. pneumophila DNA in serum are evident; serum samples are readily obtainable and can be processed within a working day.

Objective:To determine the prevalence and determinants of fecal carriage of vancomycin-resistant enterococci (VRE) in intensive care unit (ICU), hematology-oncology, and hemodialysis patients in The Netherlands.Design:Descriptive, multicenter study, with yearly 1-week point-prevalence assessments between 1995 and 1998.Population:All patients hospitalized on the testing days in ICUs and hematology-oncology wards in nine hospitals in The Netherlands were included.Methods:Rectal swabs obtained from 1,112 patients were screened for enterococci in a selective broth and subcultured on selective media with and without 6 mg/L vancomycin. Resistance genotypes were determined by polymerase chain reaction. Further characterization of VRE strains was done by pulsed-field gel electrophoresis (PFGE). We studied possible determinants of VRE colonization with a logistic regression analysis model. Determinants analyzed included gender, age, and log-transformed length of prior hospital stay.Results:The results showed that 614 (55%) of 1,112 patients were colonized with vancomycin-sensitive enterococci, and 15 (1.4%) of 1,112 carried VRE. No increase in VRE colonization was observed from 1995 to 1998. Eleven strains were identified asEnterococcus faeciumand four asEnterococcus faecalis. AllE faeciumand oneE faecaliscarried thevanAgene; the otherE faecalisstrains harbored thevanBgene. PFGE revealed that threevanBVRE isolated from patients hospitalized in one single ICU were related, suggesting nosocomial transmission. Though higher age seemed associated with VRE colonization, exclusion of patients with the nosocomial strain from the regression analysis decreased this relation to nonsignificant. Duration of hospital stay was not associated with VRE colonization.Conclusion:VRE colonization in Dutch hospitals is an infrequent phenomenon. Although nosocomial spread occurs, most observed cases were unrelated, which suggests the possibility of VRE acquisition from outside the hospital. Prolonged hospital stay, age, and gender proved unrelated to VRE colonization.

We compared 2 chromogenic media (Oxoid Brilliance MRSA 2 agar [Thermo Fisher Scientific] and MRSA-ID [bioMérieux]) for the detection of methicillin-resistant Staphylococcus aureus (MRSA) in 1,368 hospital samples. For both media, broth enrichment was essential to obtain satisfactory diagnostic performance. Although with direct cultures only, the diagnostic performance (particularly sensitivity) of Brilliance MRSA 2 agar appears better than that of MRSA-ID, no difference in sensitivity or specificity between the media was detected after inclusion of an enrichment step.

We assessed the effect of increasing manganese concentrations in test media (0.001 to 1,024 mg/liter) on MICs of tigecycline. For both broth microdilution (BMD) and Etests, this effect was negligible for physiological concentrations, but MICs increased when concentrations exceeded 8 mg/liter. Susceptibility testing should be performed on media with standardized low manganese content.

To determine the incidence and prevalence of carriage of methicillin-resistent Staphylococcus aureus (MRSA) in patients and hospital personnel, and to examine the consequences of the revised Dutch MRSA guideline with respect to patients who have frequent contact with pigs or calves (in the course of their work).Retrospective and prospective observational study using questionnaires.Since July 2006 patients who have contact with living pigs or calves have been regarded as a high-risk group for MRSA carriage, after it was established that this occupational group had an increased chance of carriage of the so-called non-typable MRSA (NT-MRSA). An inventory was made of incidence and prevalence of MRSA carriage in patients and hospital personnel, and of the consequences of the new MRSA policy, for the period July-December 2006.Information was obtained from 58 Dutch hospitals. On January 1 2007, 37 (64%) hospitals had changed their MRSA policy; 22% of the hospitals it was applied in accordance with the MRSA guideline. The new guideline resulted in an increase of MRSA screenings by 15% and of detected MRSA carriers by 44%. 73% of all MRSA screenings took place in the out-patients department. In regions with high pig-density the incidence of NT-MRSA was 12% in patients with risk factors for carriage. In 49% of the hospitals one or more NT-MRSA carriers were detected (range 1-19 carriers). Possible transmission of NT-MRSA in hospital was shown in 3 of 1,007 (0.3%) hospital personnel, but in none of the 183 fellow-patients, examined. In the same period transmission of typable MRSA was demonstrated in 41 of 2,019 (2.0%) patients and 33 of 5,190 (0.6%) of hospital personnel examined. Prevalence of NT-MRSA carriage in 6,197 screened hospital personnel was 0.05% (n = 3).The revised Dutch MRSA guideline lead to an increase in the number of MRSA screenings by 15%, particularly in the out-patients department, and to an increase in the number of detected MRSA carriers by 44%. During 306 months of observation no patient-to-patient transmission ofNT-MRSA was demonstrated.

The 'Stichting Werkgroep Antibioticabeleid' (SWAB; Dutch Working Party on Antibiotics Policy) has developed evidence-based guidelines for the antimicrobial treatment of methicillin-resistant Staphylococcus aureus (MRSA) carriers for the eradication of MRSA. A distinction was made between uncomplicated and complicated carriage depending on the presence or absence of an active MRSA infection, skin lesions, foreign body material, mupirocin resistance and/or extranasal carriage. The indication for treatment is determined by the consequences of carriage for the carrier and his/her environment, the adverse events of treatment, and the likelihood of a successful treatment. The first choice of treatment in uncomplicated carriers is a combination of mupirocin nasal ointment and disinfectant soap for 5 days, along with hygiene advice. If treatment fails, sources in the vicinity of the patient must be sought. Complicated carriers receive a combination of 2 oral antibiotics, in addition to mupirocin nasal ointment and disinfectant soap, for at least 7 days.

From the Department of Medical Microbiology and Infectious Diseases, University Medical Center, Amsterdam (J.K.), and the Laboratory for Microbiology and Infection Control, Amphia Hospital, Breda (J.K.), The Netherlands; and the Infection Control Program, University of Geneva Hospitals and Medical School, Geneva, Switzerland (S.H.). Received March 9, 2009; accepted March 11, 2009; electronically published June 3, 2009. Infect Control Hosp Epidemiol 2009; 30:633-635 2009 by The Society for Healthcare Epidemiology of America. All rights reserved. 0899-823X/2009/3007-0003$15.00. DOI: 10.1086/599020 Approximately 100,000 invasive methicillin-resistant Staphylococcus aureus (MRSA) infections occurred in 2005 in the United States, and the number of associated deaths was estimated at 19,000, which is more than the corresponding annual number of associated deaths for human immunodeficiency virus (HIV) and AIDS. With the increasing number of community-onset MRSA infections, prevention of staphylococcal infections is now more important than ever. For more than 50 years, it has been known that carriage of S. aureus plays an important role in the pathogenesis of staphylococcal infections and represents a potential target for preventive interventions. One of the first reports (1952) that clearly demonstrated the relationship between S. aureus carriage and subsequent infection involved miners who experienced beat disorders of the knees and elbows. A carefully performed microbiological survey showed that there were 24 “heavy” carriers of S. aureus among 45 beat case patients, compared with 5 heavy carriers among 45 matched control subjects without disease (odds ratio, 9.1 [95% confidence interval {CI}, 3.1–26.5]). Phagetyping showed that, in the majority of cases, the carriage strain matched the strain that caused disease. Hospital-based studies in the 1950s and 1960s confirmed this relationship, especially for surgical patients. More recently, these studies have been repeated in various other patient populations—for example, dialysis patients, patients with HIV, organ transplant recipients, and critically ill patients with intravascular catheters—with similar results. It seems obvious that eradication of S. aureus carriage can reduce the risk for infection. This strategy has been studied in several groups of patients, and a recent Cochrane review aggregated the evidence with regard to the effect of eradication of carriage on the S. aureus infection rate. Eight randomized controlled trials studied the effect of mupirocin nasal ointment in various groups of patients. The pooled estimate showed a significant reduction of the S. aureus infection rate (relative risk [RR], 0.55 [95% CI, 0.43–0.70]; ). An P ! .001 analysis of subgroups showed a pronounced effect on surgical patients and on patients who were receiving dialysis, and this fact confirms results of a previously published systematic review. Recently, a large trial was completed in which patients were screened on hospital admission for S. aureus nasal carriage by means of a 2-hour polymerase chain reaction–based assay, and carriers were subsequently randomly assigned to mupirocin nasal ointment and chlorhexidine skin washings or to placebo. The treated carriers had a significantly lower S. aureus infection rate (RR, 0.42 [95% CI, 0.23–0.75]). In addition, the length of hospital stay was significantly shortened for the group of treated carriers (mean reduction of the length of stay, 1.8 days; ). Despite the evidence that P p .04 treatment of proven carriers lowers the S. aureus infection risk, there are several issues remaining. Patients who underwent elective surgery were probably the most important group to benefit from treatment of proven carriers. Because most studies of surgical patients have included both S. aureus carriers and S. aureus noncarriers, it is difficult to assess the overall effect of treatment of proven carriers. Moreover, some studies have found that the infection rate caused by microorganisms other than S. aureus was significantly higher among patients treated with mupirocin, compared with that for control subjects (RR, 1.38 [95% CI, 1.11–1.72]). This finding was based mainly on one large study of dialysis patients who were treated repeatedly. Compared with suppression or eradication of carriage of methicillin-susceptible S. aureus, suppression or eradication of MRSA carriage remains a more difficult task. Rather than being related to pathogen-associated factors that are not fundamentally different between most methicillin-susceptible S. aureus and MRSA clones, the frequent failure of eradication treatment is related to common characteristics of MRSA carriers, such as skin lesions, catheters, and comorbidities, that make MRSA

The application of the search and destroy (S&D) policy in Scandinavian and Dutch hospitals is associated with low rates of meticillin-resistant Staphylococcus aureus (MRSA). The objective of our study was to describe the MRSA epidemiology and transmission in a Dutch hospital. This descriptive study was performed in a teaching hospital with approximately 40,000 admissions per year. In this hospital the MRSA S&D policy has been applied for several decades. MRSA epidemiology was studied during the years 2001 to 2006. The transmission rate in this hospital was determined using (1) patient's history, (2) relation in time and place to other patients or healthcare workers (HCWs), and (3) molecular typing (pulsed-field gel electrophoresis and Spa). Ninety-five persons were identified as MRSA carriers, namely 82 patients and 13 HCWs. The annual MRSA incidence increased more than three-fold during the study period, which was entirely caused by animal-related MRSA. Twenty-three percent of the patients acquired MRSA in a foreign hospital, 26% via animals, 16% by nosocomial transmission, 4% in another Dutch healthcare institution, 10% in the community via a known MRSA-positive person, and in 22% the source was unknown. For HCWs, 69% of MRSA was due to nosocomial transmission, 15% was related to working in a foreign hospital and in 15% HCWs became colonised via an MRSA-positive partner or relative. The transmission rate of 0.30 (22 secondary cases from 73 index cases) indicates that the spread of MRSA was under control during the study period, and so the S&D policy should be continued.

As long as we are able to identify the causative microorganism for infections, Staphylococcus aureus has been the most important cause of nosocomial infections (Archer 2000). The consequences of infections are severe, especially when there is no effective antimicrobial treatment available. In 1941 the mortality rate of S. aureus bacteremia at the Boston City hospital was reported to be 82% (Skinner and Keefer 1941).

Chlamydiazyme® (Abbott), an enzyme-linked immunoassay (EIA), was evaluated using cell culture on Hela 229 cells as the method of reference. Samples were acquired from 611 female and 280 male patients attending the outpatient clinic for sexually transmitted disease at the University Hospital in Rotterdam, The Netherlands. The prevalences of chlamydia culture-positive female and male patients were 7.8% and 14.4% respectively. The overall sensitivity and specificity values of the EIA were respectively 68.1% and 95.8% in the female and 92.1% and 92.0% in the male population. Samples which were culture-negative but EIA-positive were re-examined by a second direct test (IDEA; Boots Celltech). If the samples from 12 females and 11 males which were negative on culture but positive with both direct tests are considered as failures of cell culture, the sensitivity of the EIA in females almost equalled cell culture (74.6% versus 79.9%) and in males was even higher (93.9% versus 77.6%). Serotyping of the cultured strains revealed that all serovars of Chlamydia trachomatis occurring in this study could be detected by the EIA. The EIA offers a relatively simple and rapid test for diagnosis of C. trachomatis infections in high-risk populations.

Bacterial surface contamination is an important reservoir for micro-organisms and a potential route for transmission. ATP bioluminescence is a relatively new method to assess environmental contamination, and gives direct results.

Screening for staphylococci among various patient populations has become important for appropriate therapeutic management and for control of nosocomial infections. The purpose of this study is to evaluate the in vitro sensitivity and specificity of a chromogenic agar medium, S. aureus ID (bioMérieux, France), for the identification of Staphylococcus aureus.A well-defined collection of S. aureus and coagulase-negative staphylococci (CNS) was used. The methicillin-resistant S. aureus (MRSA) isolates were collected in The Netherlands and all had a unique typing pattern. The methicillin-susceptible S. aureus (MSSA) and CNS were isolated from cultures of blood. The isolates were inoculated on Columbia agar plates with 5% sheep blood and incubated for 24 h at 35 degrees C. From the resulting cultures, a suspension of 0.5 McFarland was made and subsequently 10 mul was streaked on a S. aureus ID plate using a sterile loop. The results were read after 24 h and 48 h of incubation at 35 degrees C. Growth of colonies showing green coloration was considered to be positive (indicating S. aureus).A total of 519 S. aureus strains were tested (249 MSSA, 270 MRSA). The sensitivity to detect S. aureus was 96.5% (501/519) after 24 h and 97.5% (506/519) after 48 h. A total of 478 CNS were tested. The specificity was 98.5% (471/478) after 24 h and 98.3% (470/478) after 48 h. The differences between 24 h and 48 h incubation were not statistically significant.S. aureus ID is highly sensitive and specific to differentiate between S. aureus and CNS in vitro. Since the performance does not significantly differ between 24 h or 48 h of incubation, samples need only 1 day of incubation before optimal results can be obtained.

Isolation of patients is used to control the spread of certain microorganisms in the hospital, e.g. meticillin-resistant Staphylococcus aureus (MRSA). Recent investigations have shown that the quality of care for patients in isolation is affected significantly. However, this is not accompanied by an effect on the morbidity or mortality. The successful Dutch policy on MRSA is based largely on strict isolation of patients colonised with MRSA. If MRSA becomes endemic, this is accompanied by increases in morbidity and mortality as well as costs. The disadvantages of isolation are recognised and should be prevented as far as possible. New diagnostic and therapeutic developments can shorten the duration of isolation significantly, which will further improve the quality of care.

Contains fulltext : 57483.pdf (Publisher’s version ) (Closed access) In the Netherlands, less than 1% of clinical isolates of Staphylococcus aureus are methicillin-resistant (MRSA). A national search and destroy policy prevents MRSA from becoming endemic. Some MRSA outbreaks cannot be related to patients at risk for MRSA carriage. This study was designed to measure the prevalence of MRSA among patients without risk factors for MRSA carriage at the time of admission to the hospital. In four Dutch hospitals, patients admitted to non-surgical departments in the period 1999-2000 were screened for MRSA nasal carriage. Nasal swabs were streaked on 5% sheep blood agar (BA), submerged in a selective broth, and incubated for two to three days at 35 degrees C. Colonies suspected of being S. aureus were identified with an agglutination test. Susceptibility testing was performed by an automated system and additional oxacillin disk diffusion. Methicillin resistance was confirmed by a DNA hybridization test and mecA PCR. MRSA strains were genotyped by pulsed-field gel electrophoresis (PFGE). Twenty-four percent (2332/9859) of the patients were S. aureus nasal carriers. Only three (0.03%) patients were MRSA carriers. These patients were not repatriated, nor known to be MRSA carriers before screening. Genotyping revealed that the strains were not clonally related and were not related to MRSA outbreaks in the hospital where the patients were admitted. We conclude that at routine admission to a Dutch hospital (excluding high-risk foreign admissions) the MRSA prevalence is low (0.03%), due to the Dutch search and destroy policy and restrictive antibiotic prescribing.

Humans are a natural reservoir for Staphylococcus aureus. This micro-organism is a frequent cause of clinically important infections, including bacteremia, metastatic abscesses, septic arthritis, pneumonia, osteomyelitis, and wound infections [1]. Many of these infections are nosocomial and lead to increased hospital stay, antibiotic use, costs, and mortality [2]. Due to an increasing number of infections caused by methicillin-resistant S. aureus (MRSA) strains, which are now most often multi-resistant, therapy has become problematic. Even more worrying is the fact that recently the first vancomycin-resistant S. aureus has been cultured in the United States [3]. Therefore, prevention of staphylococcal infections is of the uttermost importance.

Nosocomial bloodstream infections are frequent and serious complications of modern medicine. Each infection accounts for an estimated $6000 increase in hospital costs (1). In the ICU the incremental costs were calculated at $40,000 per survivor (2). Moreover the case fatality rate has been high, over 20% in two recent studies (2,3). Prevention of nosocomial bloodstream infections is therefore important. Prevention should be aimed at the primary source of the infection. When bloodstream infections are secondary to a source of infection elsewhere in the body, prevention should be aimed at this source and is beyond the scope of this chapter. This chapter focuses on the prevention of bloodstream infections due to intravascular devices.

Recently, the epidemiology of MRSA has changed. Community-acquired MRSA is increasing. The objective of this study was to investigate the determinants of MRSA carriage/infections in The Netherlands.

s, 7th International Conference of the Hospital Infection Society, 10–13 October 2010, Liverpool, UK / Journal of Hospital Infection 76S1 (2010) S1–S90 S53 flagging system for at risk patients was developed and implemented in October 2005. Education was delivered through formal and informal means. HCWwere targeted at both undergraduate through links with academic bodies and postgraduate level through practice support programs and medical grand rounds etc. Specific clinical units were targeted as part of outbreak management. The audit was repeated in 2008 and 2010 using the same tool. Comparable audit reports were widely disseminated to clinicians and hospital management. Results: Between April 2005 and April 2010 a significant improvement in practice of TBP was observed. Up to 90% of patients colonised/infected with meticillin resistant Staphyloccus aureus (MRSA) were isolated/cohorted in 2010. Conclusions: Sustained education, audit and feedback, supported by protocols and risk management tools have influenced staff knowledge of IPC practices and strategies to control spread of transmissible organisms. Although practice improvement is apparent there remain deficits and challenges in the application of TBP in this hospital. P17.02 An outbreak Of Staphylococcus aureus after thoracoscopy Y. Hendriks, H. Coertjens, M. v. Rijen, J. Kluytmans. Amphia Hospital, Netherlands Background: In a period of 6 weeks there were 4 patients with a Staphylococcus aureus infection after thoracoscopy. Objective: To investigate and control an outbreak of S. aureus after thoracoscopy. Methods: The department of Infection control audited the procedures during thoracoscopy. The healthcare workers (HCW) who were present during the procedures were screened for nasal carriage of S. aureus. All isolates were typed (AFLP). Results: The audit demonstrated that the thoracoscopy took place in a standard hospital room instead of a operation room class II (as recommended by the National guidelines), multiple breaks in infection principles during the procedure e.g. no scrub suits and the lack of knowledge of universal principles of hygiene. AFLP learned that three of the four patients were infected with the same strain. Twelve out of 31 (39%) HCW were nasal carriers of S. aureus. One of the HCW had the same type as the three patients. The following corrective actions were implemented: the HCW with the outbreak strain was treated for carriage and not allowed to work until eradication was achieved, thoracoscopy procedures were performed in the operating theatre, HCW involved in the procedures were trained in the principles of infection control. Follow up during >12 months revealed no infections after thoracoscopy. Of note, the HCW who carried the outbreak strain was recolonised with the same strain 5 months after the eradication treatment. She is allowed to work with this strain under the assumption that the current control measures prevent the spread to patients. No further infections have been found. Conclusions: An outbreak of S. aureus infections after thoracoscopy was traced to a colonised HCW. The suboptimal environmental conditions and breaks in general hygienic measures during the procedures were probably the main cause of the outbreak. The outbreak was terminated by improving the environmental conditions as well as the behavior of the HCW. P17.03 Infection control measures taken during lumbar punctures: a survey of current practice S. Kelly, R. Malhotra. University Hospital Coventry and Warwickshire, United Kingdom; Weston General Hospital, United Kingdom Background: Infective complications of lumbar puncture are not common but are a significant source of morbidity and mortality. It is likely that adhering to infection control measures when carrying out a lumbar puncture will minimize the risk of iatrogenic meningitis. However there is no clear consensus in the literature as to the most appropriate methods to use. Objective: The aim of this survey was to assess what infection control measures doctors currently use when performing lumbar punctures. Methods: We constructed an anonymous, tick-box survey asking about specific infection control measures taken when performing lumbar punctures. This was distributed to doctors in all medical specialties in the West Midlands and Severn Deaneries. Results: The response rate was 63% (119/188 responses) but 12 forms were incomplete and so not included. According to grade, we surveyed 62 (58%) CT1–2 doctors, 27 (25%) ST3–5 doctors and 18 (17%) Senior Registrars. Responders had performed, on average, a total of 16 lumbar punctures (range 3–45). Results show that all doctors use hand-washing, sterile gloves and skin preparation but significant numbers never wore facemasks or caps (Table 1). CT 1–2 doctors were three times more likely than SpRs to perform all of the infection control measures stated (36% vs. 10%, Table 2). Similarly, the number of infection control measures taken by doctors decreased with the number of times the procedure had been performed. Table 1. Infection control measures taken by doctors when performing

Several studies have postulated a link between infectious agents and atherosclerosis (3, 12). Epidemiological and pathological studies have shown an association between Chlamydia pneumoniae and atherosclerosis (3, 12). C. pneumoniae has been detected in vascular tissues and degenerative heart valves (3, 9). It has been suggested that Mycoplasma pneumoniae might also play a role in the development of atherosclerosis (12). Myocarditis, pericarditis, cerebral stroke, and vasculitis have been previously associated with M. pneumoniae infection (1, 4, 5, 11). M. pneumoniae might be seen as a plausible candidate to play a role in the pathogenesis of atherosclerosis, because it has been related to cardiovascular disease and its ability to induce chronic inflammation (12). Taylor-Robinson and Thomas have postulated that there is a need to investigate the presence of M. pneumoniae in vascular tissues, because there is a similarity in epidemiological behavior and antibiotic susceptibility between M. pneumoniae and C. pneumoniae (12). Furthermore, M. fermentans has been detected in 1 of 19 human arterial specimens that were positive for C. pneumoniae (10), and it has been shown that M. gallisepticum exhibits tropism for arterial tissue in turkeys (2). However, nothing is known about the presence of M. pneumoniae in human atherosclerotic vascular tissues. Therefore, we investigated the presence of M. pneumoniae in atherectomy specimens and in degenerative heart valve (DHV) specimens. Atherectomy specimens (n = 39) and DHV specimens (n = 64) were obtained from patients undergoing cardiac surgery for coronary artery bypass graft surgery and heart valve replacement, respectively. Specimens were transported in a Tris-EDTA buffer containing 0.5% sodium dodecyl sulfate. DNA extraction was performed using a commercial kit (QiAmp DNA Minikit; Qiagen, Hilden, Germany). Detection of M. pneumoniae was performed by a PCR assay based on the P1 adhesin gene and using the primers Pn1 (5′-GCC ACC CTC GGG GGC AGT CAG-3′) and Pn2 (5′-GAG TCG GGA TTC CCC GCG GAG G-3′) as described previously (7). PCR products were visualized after electrophoresis in 2% ethidium bromide-stained agarose gels (Fig. ​(Fig.1).1). To confirm the PCR results, the PCR product was spotted and hybridized with the 5′-biotinylated probe MP2-B (5′-GGT GAA GGA ATG ATA AGG CT-3′). Hybridization signals were visualized using streptavidin-peroxidase and enhanced chemiluminescence (ECL) detection reagents (Amersham, Little Chalfont, United Kingdom). FIG. 1 Agarose gel electrophoresis of PCR products obtained with P1 adhesin gene primers. (A) Lane M, 1-kb ladder; lanes 1 to 5, vascular tissues of five patients; lane 6, negative control. (B) Lanes 1 to 6 contain the same samples shown in panel A spiked with ... M. pneumoniae was detected in only 1 (2.5%) of the 39 atherectomy specimens and in 2 (3%) of the 64 DHV specimens. This is the first study on detection of M. pneumoniae in vascular tissues. Thus, there are no other data available to compare our results with. In general, several factors can influence the results of PCR-based studies on detection of microorganisms in vascular tissues, including contamination, inhibition, size and composition of specimens, and the lack of standardized methods for DNA extraction and PCR assays (8). We used a validated PCR assay with a high sensitivity (92 to 100%) (7). Strict PCR anticontamination precautions were taken, such as the use of UDG/dUTP, to prevent carryover of previous PCRs. Sample processing and the PCR assay were performed in separate rooms. A negative control was processed with every set of five samples. To control for inhibition of the PCR, a second sample of each specimen was spiked with M. pneumoniae target DNA, and inhibited PCR samples were again purified and retested. Also, this PCR assay was used in our laboratory on respiratory samples. A total of 179 throat samples obtained from patients with respiratory tract infections were tested. These samples were sent to the laboratory for detection of respiratory pathogens. The M. pneumoniae PCR detected M. pneumoniae in 27 (16%) of the 179 samples. These results indicate that the PCR assay we used was sensitive and able to detect M. pneumoniae. However, it should be mentioned that there is no similarity in composition between vascular tissues and throat specimens. It has been found in a serological study that, in contrast to C. pneumoniae antibodies, M. pneumoniae antibodies are not associated with recurrent events in patients with unstable angina (6). Using PCR, we were unable to detect M. pneumoniae in the great majority of the 103 tested specimens. The results of this study do not support the hypothesis that M. pneumoniae is an important factor in the development of vascular disease. Further investigations are needed to confirm our results.

Nosocomial transmission is considered to be the most important source for MRSA colonisation of health care workers (HCW). However, the epidemiology is changing and community-acquired MRSA is increasing. The objective of this study was to investigate the determinants of MRSA carriage/infections in HCW in The Netherlands.

The MRSA Search-and-Destroy strategy relies on active screening of high risk groups. However, not all carriers belong to known risk groups and MRSA in the community is emerging also in the Netherlands.

The prevalence of Extended Spectrum Beta-Lactamase producing Enterobacteriaceae (ESBL-E) is rapidly increasing worldwide. This study aimed to determine the prevalence of ESBL-E carriage in hospitalised patients and the relative contribution of nosocomial acquisition.