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Objectives: To investigate the molecular epidemiology, antimicrobial susceptibility and carbapenem resistance determinants of Acinetobacter baumannii isolates from respiratory tract samples of patients diagnosed with ventilator-associated pneumonia (VAP) who were enrolled in the MagicBullet clinical trial., Methods: A. baumannii isolates were prospectively cultured from respiratory tract samples from 65 patients from 15 hospitals in Greece, Italy and Spain. Susceptibility testing was performed by broth microdilution. Carbapenem resistance determinants were identified by PCR and sequencing. Molecular epidemiology was investigated using rep-PCR (DiversiLab) and international clones (IC) were identified using our in-house database., Results: Of 65 isolates, all but two isolates (97%) were resistant to imipenem and these were always associated with an acquired carbapenemase, OXA-23 (80%), OXA-40 (4.6%), OXA-58 (1.5%) or OXA-23/58 (1.5%). Resistance to colistin was 47.7%. Twenty-two isolates were XDR, and 20 isolates were pandrug-resistant (PDR). The majority of isolates clustered with IC2 (n = 54) with one major subtype comprising isolates from 12 hospitals in the three countries, which included 19 XDR and 16 PDR isolates., Conclusions: Carbapenem resistance rates were very high in A. baumannii recovered from patients with VAP. Almost half of the isolates were colistin resistant, and 42 (64.6%) isolates were XDR or PDR. Rep-PCR confirmed IC2 is the predominant clonal lineage in Europe and suggests the presence of an epidemic XDR/PDR A. baumannii clone that has spread in Greece, Italy and Spain. These data highlight the difficulty in empirical treatment of patients with A. baumannii VAP in centres with a high prevalence of carbapenem-resistant A. baumannii., (© The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.)

Background: Continuation of empirical antimicrobial therapy (EAT) for febrile neutropenia in patients with haematological malignancies until neutrophil recovery could prolong the therapy unnecessarily. We aimed to establish whether EAT discontinuation driven by a clinical approach regardless of neutrophil recovery would optimise the duration of therapy., Methods: We did an investigator-driven, superiority, open-label, randomised, controlled phase 4 clinical trial in six academic hospitals in Spain. Eligible patients were adults with haematological malignancies or haemopoietic stem-cell transplantation recipients, with high-risk febrile neutropenia without aetiological diagnosis. An independent, computer-generated randomisation sequence was used to randomly enrol patients (1:1) to the experimental or control group. Investigators were masked to assignment only before randomisation. EAT based on an antipseudomonal β-lactam drug as monotherapy (ceftazidime or cefepime, meropenem or imipenem, or piperacillin-tazobactam) or as combination therapy (with an aminoglycoside, fluoroquinolone, or glycopeptide) was started according to local protocols and following international guidelines and recommendations. For the experimental group, EAT was withdrawn after 72 h or more of apyrexia plus clinical recovery; for the control group, treatment was withdrawn when the neutrophil count was also 0·5 × 10 9 cells per L or higher. The primary efficacy endpoint was the number of EAT-free days. Primary analyses were done in the intention-to-treat population. Efficacy and safety analyses were done in the intention-to-treat population and the per-protocol population. This trial is registered with ClinicalTrials.gov, number NCT01581333., Findings: Between April 10, 2012, and May 31, 2016, 157 episodes among 709 patients assessed for eligibility were included in analyses. 78 patients were randomly assigned to the experimental group and 79 to the control group. The mean number of EAT-free days was significantly higher in the experimental group than in the control group (16·1 [SD 6·3] vs 13·6 [7·2], absolute difference -2·4 [95% CI -4·6 to -0·3]; p=0·026). 636 adverse events were reported (341 in the experimental group vs 295 in the control group; p=0·057) and most (580 [91%]; 323 in the experimental group vs 257 in the control group) were considered mild or moderate (grade 1-2). The most common adverse events in the experimental versus the control group were mucositis (28 [36%] of 78 patients vs 20 [25%] of 79 patients), diarrhoea (23 [29%] of 78 vs 24 [30%] of 79), and nausea and vomiting (20 [26%] of 78 vs 22 [28%] of 79). 56 severe adverse events were reported, 18 in the experimental group and 38 in the control group. One patient died in the experimental group (from hepatic veno-occlusive disease after an allogeneic haemopoietic stem-cell transplantation) and three died in the control group (one from multiorgan failure, one from invasive pulmonary aspergillosis, and one from a post-chemotherapy intestinal perforation)., Interpretation: In high-risk patients with haematological malignancies and febrile neutropenia, EAT can be discontinued after 72 h of apyrexia and clinical recovery irrespective of their neutrophil count. This clinical approach reduces unnecessary exposure to antimicrobials and it is safe., Funding: Instituto de Salud Carlos III, Spanish Ministry of Economy (PI11/02674)., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: The global crisis of bacterial resistance urges the scientific community to implement intervention programs in healthcare facilities to promote an appropriate use of antibiotics. However, the clinical benefits or the impact on resistance of these interventions has not been definitively proved., Methods: We designed a quasi-experimental intervention study with an interrupted time-series analysis. A multidisciplinary team conducted a multifaceted educational intervention in our tertiary-care hospital over a 5-year period. The main activity of the program consisted of peer-to-peer educational interviews between counselors and prescribers from all departments to reinforce the principles of the proper use of antibiotics. We assessed antibiotic consumption, incidence density of Candida and multidrug-resistant (MDR) bacteria bloodstream infections (BSIs) and their crude death rate per 1000 occupied bed days (OBDs)., Results: A quick and intense reduction in antibiotic consumption occurred 6 months after the implementation of the intervention (change in level, -216.8 defined daily doses per 1000 OBDs; 95% confidence interval, -347.5 to -86.1), and was sustained during subsequent years (average reduction, -19,9%). In addition, the increasing trend observed in the preintervention period for the incidence density of candidemia and MDR BSI (+0.018 cases per 1000 OBDs per quarter; 95% confidence interval, -.003 to .039) reverted toward a decreasing trend of -0.130 per quarter (change in slope, -0.029; -.051 to -.008), and so did the mortality rate (change in slope, -0.015; -.021 to -.008)., Conclusions: This education-based antimicrobial stewardship program was effective in decreasing the incidence and mortality rate of hospital-acquired candidemia and MDR BSI through sustained reduction in antibiotic use., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Outer membrane protein A (OmpA) is a porin involved in Acinetobacter baumannii pathogenesis. However, OmpA clinical implication in hospital-acquired infections remains unknown. We aimed to determine whether OmpA overproduction was a risk factor associated with pneumonia, bacteremia, and mortality., Methods: We analyzed demographic, microbiological, and clinical data from 100 patients included in a unicenter cohort and 246 included in a unicenter cohort and a multicenter cohort. Representative isolates were classified into 2 groups: (1) isolates from patients colonized by A. baumannii (16 from the unicenter and 20 from the multicenter cohort) and (2) isolates from bacteremic or nonbacteremic patients with pneumonia (PP) caused by A. baumannii (13 from the unicenter and 23 from the multicenter cohort) Expression of ompA was determined with quantitative reverse-transcription polymerase chain reaction., Results: Isolates from PP overexpressed more ompA than those from colonized patients from the unicenter (ratio, 1.76 vs 0.36; P < .001) and the multicenter (1.36 vs 0.91; P = .03) cohorts. Among isolates from PP, those from bacteremic patients overexpressed nonsignificantly more ompA than those from nonbacteremic patients in the unicenter (ratio, 2.37 vs 1.43; P = .06) and the multicenter (2.03 vs 0.91; P = .14) cohorts. Multivariate analysis in both cohorts together showed ompA overexpression as independent risk factor for pneumonia (P < .001), bacteremia (P = .005), and death (P = .049)., Conclusions: These data suggest that ompA overexpression is an associated factor for pneumonia, bacteremia, and death due to A. baumannii., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Rapid antimicrobial susceptibility testing has the potential to improve patient outcomes and reduce healthcare-associated costs. In this study, a novel assay based on bacterial cell elongation after exposure to an antibiotic (ceftazidime) was evaluated for its ability to rapidly detect resistance in Gram-negative bacteria. The assay was used to detect resistance in a large collection of strains containing 320 clinical isolates of Acinetobacter baumannii, 171 clinical isolates of Klebsiella pneumoniae, and 212 clinical isolates of Pseudomonas aeruginosa, and the results were compared to those obtained using standard antimicrobial susceptibility testing methods. The assay identified ceftazidime-resistant strains with 100% sensitivity and 100% specificity for A. baumannii, 100% sensitivity and 97.2% specificity for K. pneumoniae, and with 82.3% sensitivity and 100% specificity for P. aeruginosa. Importantly, results were obtained in 1 hour 15 minutes from exponentially growing cultures. This study demonstrates that changes in cell length are highly correlated with phenotypic antibiotic susceptibility determined using standard susceptibility testing methods. This study therefore provides proof-of-concept that changes in cell morphology can be used as the basis for rapid detection of antibiotic resistance and provides the basis for the development of novel rapid diagnostics for the detection of antibiotic resistance.

Objectives: This study aims to analyze the mortality and the length of ICU stay (LOS) of A. baumannii VAP compared to respiratory colonization in patients with mechanical ventilation (MV)., Methods: A prospective cohort study was performed in an ICU of adult patients (February 2010-June 2011). One hundred patients on MV with A. baumannii in lower respiratory airways were recruited, and classified as VAP or airways colonization according to CPIS criteria, with a punctuation ≥6. LOS, 30-days mortality, A. baumannii bacteremia, and clinical features including antibiotic therapy were recorded. Multivariate analysis (linear and Cox regression) and survival analysis (Kaplan-Meier curves) were performed., Results: Fifty-seven VAP and 43 colonized A. baumannii patients were analyzed. Among the A. baumannii strains, 99% were non-susceptible to carbapenems and the MIC90 of colistin was 0.12 mg/l. Therapy was appropriate in 94.6% of VAP patients, most of them with colistin 6 MIU/day, although in 13 (23.6%) cases colistin was started 48 hours after the onset of VAP. Mortality was similar in both groups (VAP 24.6% vs. colonized 27.9%, p = 0.7). Bacteremia and acute kidney insufficiency were associated with decreased survival (p = 0.02 and p = 0.04, respectively) in VAP patients. LOS was 21.5 (11.5-42.75) vs. 9 (6-22) days for VAP and colonized patients (p = 0.004). VAP (p = 0.003) and age (p = 0.01) were independently related to a longer LOS., Conclusions: Multidrug-resistant A. baumannii VAP treated with colistin does not have a different mortality compared to lower airways colonization, among patients on mechanical-ventilation, in a setting of high susceptibility to colistin of A. baumannii., Competing Interests: The authors have declared that no competing interests exist.

Acinetobacter baumannii is a successful nosocomial pathogen due to its ability to persist in hospital environments by acquiring mobile elements such as transposons, plasmids, and phages. In this study, we compared two genomes of A. baumannii clinical strains isolated in 2000 (ST-2&#95;clon&#95;2000) and 2010 (ST-2&#95;clon&#95;2010) from GenBank project PRJNA308422., (Copyright © 2016 López et al.)

Real-time polymerase chain reaction (PCR)-based approaches have not been assessed in terms of their ability to detect patients colonized by Acinetobacter baumannii during active surveillance. This prospective, double-blind study demonstrated that a real-time PCR assay had high sensitivity (100%) and specificity (91.2%) compared with conventional culture for detecting A. baumannii in 397 active surveillance samples, and provided results within 3h. Receiver-operator curve analyses demonstrated that the technique has diagnostic accuracy of 97.7% (95% confidence interval 96.0-99.3%). This method could facilitate the rapid implementation of infection control measures for preventing the transmission of A. baumannii., (Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.)

Objectives: Data about the efficacy of ertapenem for the treatment of bloodstream infections (BSI) due to ESBL-producing Enterobacteriaceae (ESBL-E) are limited. We compared the clinical efficacy of ertapenem and other carbapenems in monomicrobial BSI due to ESBL-E., Methods: A multinational retrospective cohort study (INCREMENT project) was performed (ClinicalTrials.gov identifier: NCT01764490). Patients given monotherapy with ertapenem or other carbapenems were compared. Empirical and targeted therapies were analysed. Propensity scores were used to control for confounding; sensitivity analyses were performed in subgroups. The outcome variables were cure/improvement rate at day 14 and all-cause 30 day mortality., Results: The empirical therapy cohort (ETC) and the targeted therapy cohort (TTC) included 195 and 509 patients, respectively. Cure/improvement rates were 90.6% with ertapenem and 75.5% with other carbapenems (P = 0.06) in the ETC and 89.8% and 82.6% (P = 0.02) in the TTC, respectively; 30 day mortality rates were 3.1% and 23.3% (P = 0.01) in the ETC and 9.3% and 17.1% (P = 0.01) in the TTC, respectively. Adjusted ORs (95% CI) for cure/improvement with empirical and targeted ertapenem were 1.87 (0.24-20.08; P = 0.58) and 1.04 (0.44-2.50; P = 0.92), respectively. For the propensity-matched cohorts it was 1.18 (0.43-3.29; P = 0.74). Regarding 30 day mortality, the adjusted HR (95% CI) for targeted ertapenem was 0.93 (0.43-2.03; P = 0.86) and for the propensity-matched cohorts it was 1.05 (0.46-2.44; P = 0.90). Sensitivity analyses were consistent except for patients with severe sepsis/septic shock, which showed a non-significant trend favouring other carbapenems., Conclusions: Ertapenem appears as effective as other carbapenems for empirical and targeted therapy of BSI due to ESBL-E, but further studies are needed for patients with severe sepsis/septic shock., (© The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

The increasing number of infections produced by beta-lactam-resistant Gram-positive bacteria and the morbidity secondary to these infections make it necessary to optimize the use of vancomycin. In 2009, the American Society of Health-System Pharmacists, the Infectious Diseases Society of America, and the Society of Infectious Disease Pharmacists published specific guidelines about vancomycin dosage and monitoring. However, these guidelines have not been updated in the past 6 years. This review analyzes the new available information about vancomycin published in recent years regarding pharmacokinetics and pharmacodynamics, serum concentration monitoring, and optimal vancomycin dosing in special situations (obese people, burn patients, renal replacement therapy, among others). Vancomycin efficacy is linked to a correct dosage which should aim to reach an area under the curve (AUC)/MIC ratio of ≥400; serum trough levels of 15 to 20 mg/liter are considered a surrogate marker of an AUC/MIC ratio of ≥400 for a MIC of ≤1 mg/liter. For Staphylococcus aureus strains presenting with a MIC >1 mg/liter, an alternative agent should be considered. Vancomycin doses must be adjusted according to body weight and the plasma trough levels of the drug. Nephrotoxicity has been associated with target vancomycin trough levels above 15 mg/liter. Continuous infusion is an option, especially for patients at high risk of renal impairment or unstable vancomycin clearance. In such cases, vancomycin plasma steady-state level and creatinine monitoring are strongly indicated., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

Objectives: The objective of this study was to analyse whether there is an association between reduced susceptibility to biocides in Acinetobacter baumannii and (i) antimicrobial resistance (co-resistance), (ii) prevalent (epidemic) clones, (iii) changes in the fitness or (iv) expression of genes related to efflux pumps and porins., Methods: Susceptibility to biocides and antimicrobials was determined in 49 clonally unrelated isolates of A. baumannii. Biological cost, in terms of mean generation time, was determined by spectrophotometry. Quantitative real-time RT-PCR was used to determine the relative expression of genes encoding several efflux pumps and porins., Results: Reduced susceptibility to chlorhexidine digluconate, benzalkonium chloride and Irgasan(®) was associated with resistance to aminoglycosides, tetracycline and ciprofloxacin (P < 0.05). The MICs of carbapenems, aminoglycosides, doxycycline and ciprofloxacin for isolate Ab70 (epidemic clone) exposed to these biocides increased by ≥2 dilutions. Reduced susceptibility to Orsan(®) was more frequent among prevalent clones than non-prevalent clones (P < 0.05). Mean generation times for Ab70 before and after exposure to benzalkonium chloride were 57.8 and 78.1 min, respectively (P = 0.02). Relative expression of abeS and adeB was increased in Ab46 and Ab70 after exposure to chlorhexidine digluconate, but was decreased for ompA and carO after exposure to Irgasan(®)., Conclusions: Reduced susceptibility to biocides is associated with co-resistance to carbapenems, aminoglycosides, tetracycline and ciprofloxacin. Reduced susceptibility to Orsan(®) may be a marker of prevalent clones. Acquisition of reduced susceptibility to benzalkonium chloride has a biological cost. Exposure to biocides affects the relative expression of genes related to some efflux pump genes (increased expression) or porins (reduced expression)., (© The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Urinary tract infections (UTI) are one of the most common infections in solid organ transplant (SOT) recipients. A systematic review was performed to assess the management of UTI in SOT recipients. Recommendations are provided on the management of asymptomatic bacteriuria, and prophylaxis and treatment of UTI in SOT recipients. The diagnostic-therapeutic management of recurrent UTI and the role of infection in kidney graft rejection or dysfunction are reviewed. Finally, recommendations on antimicrobials and immunosuppressant interactions are also included., (Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

Introduction: Acinetobacter baumannii constitutes a dreadful problem in many ICUs worldwide. The very limited therapeutic options available for these organisms are a matter of great concern. No specific guidelines exist addressing the prevention and management of A. baumannii infections in the critical care setting., Methods: Clinical microbiologists, infectious disease specialists and intensive care physicians were invited by the Chair of the Infection Section of the ESICM to participate in a multidisciplinary expert panel. After the selection of clinically relevant questions, this document provides recommendations about the use of microbiological techniques for identification of A. baumannii in clinical laboratories, antibiotic therapy for severe infections and recommendations to control this pathogen in outbreaks and endemic situations. Evidence supporting each statement was graded according to the European Society of Clinical Microbiology and Infection Diseases (ESCMID) grading system., Results: Empirical coverage of A. baumannii is recommended in severe infections (severe sepsis or septic shock) occurring during an A. baumannii outbreak, in an endemic setting, or in a previously colonized patient. For these cases, a polymyxin is suggested as part of the empirical treatment in cases of a high suspicion of a carbapenem-resistant (CR) A. baumannii strain. An institutional program including staff education, promotion of hand hygiene, strict contact and isolation precautions, environmental cleaning, targeted active surveillance, and antimicrobial stewardship should be instituted and maintained to combat outbreaks and endemic situations., Conclusions: Specific recommendations about prevention and management of A. baumannii infections in the ICU were elaborated by this multidisciplinary panel. The paucity of randomized controlled trials is noteworthy, so these recommendations are mainly based on observational studies and pharmacodynamics modeling.

Background: Urinary tract infections (UTIs) are one of the most common infections in solid organ transplant (SOT) recipients., Methods: Experienced SOT researchers and clinicians have developed and implemented this consensus document in support of the optimal management of these patients. A systematic review was conducted, and evidence levels based on the available literature are given for each recommendation. This article was written in accordance with international recommendations on consensus statements and the recommendations of the Appraisal of Guidelines for Research and Evaluation II (AGREE II)., Results: Recommendations are provided on the management of asymptomatic bacteriuria, and prophylaxis and treatment of UTI in SOT recipients. The diagnostic-therapeutic management of recurrent UTI and the role of infection in kidney graft rejection or dysfunction are reviewed. Finally, recommendations on antimicrobials and immunosuppressant interactions are also included., Conclusions: The latest scientific information on UTI in SOT is incorporated in this consensus document., (Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

The spread of multidrug-resistant Enterobacteriaceae related to the production of extended-spectrum β-lactamases (ESBL) and carbapenemases is a serious public health problem worldwide. Microbiological diagnosis and therapy of these infections are challenging and controversial. After the selection of clinically relevant questions, this document provides evidence-based recommendations for the use of microbiological techniques for the detection of ESBL- and carbapenemase-producing Enterobacteriaceae, and for antibiotic therapy for invasive infections caused by these organisms. The absence of randomized-controlled trials is noteworthy, thus recommendations are mainly based on observational studies, that have important methodological limitations, pharmacokinetic and pharmacodynamics models, and data from animal studies. Additionally, areas for future research were identified., (Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

The spread of multidrug-resistant Enterobacteriaceae related to the production of extended-spectrum β-lactamases and carbapenemases is a serious public health problem worldwide. Microbiological diagnosis and therapy of these infections are challenging and controversial. Clinically relevant questions were selected and the literature was reviewed for each of them. The information from the selected articles was extracted and recommendations were provided and graded according to the strength of the recommendations and quality of the evidence. The document was opened to comments from the members from the Spanish Society of Infectious Diseases and Clinical Microbiology, which were considered for inclusion in the final version. Evidence-based recommendations are provided for the use of microbiological techniques for the detection of extended-spectrum β-lactamases and carbapenemases in Enterobacteriaceae, and for antibiotic therapy for invasive/severe infections caused by these organisms. The absence of randomised controlled trials is noteworthy; thus, recommendations are mainly based on observational studies (that have important methodological limitations), pharmacokinetic and pharmacodynamics models, and data from animal studies. Additionally, areas for future research were identified., (Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

Background: Ventilator-associated pneumonia (VAP) is one of the most common and severe hospital-adquired infections, and multidrugresistant gram-negative bacilli (MDR-GNB) constitute the main etiology in many countries. Inappropriate empiric antimicrobial treatment is associated with increased mortality. In this context, the empirical treatment of choice for VAP is unknown. Colistin, is now the antimicrobial with greatest in vitro activity against MDR-GNB., Methods/design: The MagicBullet clinical trial is an investigator-driven clinical study, funded by the Seventh Framework Program of the European Commission. This is designed as a phase IV, randomized, controlled, open label, non-inferiority and international trial to assess the safety and efficacy of colistin versus meropenem in late onset VAP. The study is conducted in a total of 32 centers in three European countries (Spain, Italy and Greece) with specific high incidences of infections caused by MDR-GNB. Patients older than 18 years who develop VAP with both clinical and radiological signs, and are on mechanical ventilation for more than 96 hours, or less than 96 hours but with previous antibiotic treatment plus one week of hospitalization, are candidates for inclusion in the study. A total sample size of 496 patients will be randomized according to a severity clinical score (at the time of VAP diagnosis in a 1:1 ratio to receive either colistin 4.5 MU as a loading dose, followed by 3 MU every eight hours (experimental arm), or meropenem 2 g every eight hours (control arm), both combined with levofloxacin. Mortality from any cause at 28 days will be considered as the main outcome. Clinical and microbiological cure will be evaluated at 72 hours, eight days, the finalization of antibiotic treatment, and 28 days of follow-up. The efficacy evaluation will be performed in every patient who receives at least one study treatment drug, and with etiologic diagnosis of VAP, intention-to-treat population and per protocol analysis will be performed., Discussion: Currently, there is no study being undertaken which analyzes empiric treatment of (VAP) with a suspicion of multi-resistance. Colistin, an off-patent antibiotic commercialized for more than 60 years, could widen the antibiotic alternatives for a high-mortality illness aggravated by antibiotic resistance., Trial Registration: This trial is registered with ClinicalTrials.gov (identifier: NCT01292031 ; registered on 29 June 2012) and EudraCT (identifier: 2010-023310-31; registered on 7 February 2011).

Infectious diseases referrals (IDR) is a core activity of infectious diseases departments, and is certainly the one with the greatest potential impact on the hospital due to their cross-sectional nature, and with the emergence of a bacterial resistance and antimicrobial crisis. However, there is no standard model for IDR, no official training, and evaluation is merely descriptive. Paradoxically IDR are at risk in a health system that demands more quality and efficiency. The aim of this review is to assess what is known about IDR, its definition, key features, objectives, method, and the evaluation of results, and to suggest improvements to this key activity for the infectious diseases departments and the hospital., (Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

The aim of this study was to characterize timing, kinetic, and magnitude of CMV-specific immune response after hematopoietic stem cell transplantation (HSCT) and its ability to predict CMV replication and clinical outcomes. Using cell surface and intracellular cytokine staining by flow cytometry, CMV-specific T-cell response was measured in blood, while CMV viral load and chimerism were determined by real-time PCR. Patients that reconstituted CMV-specific T-cell response within 6 weeks after Allo-SCT showed a more robust immune response (CD8(+) : 0.7 cells/μl vs. 0.3/μl; P-value = 0.01), less incidence of CMV replication (33% vs. 89.5%; P-value = 0.007), reduced viral loads (1.81 log copies/ml vs. 0 copies/ml; P-value = 0.04), and better overall survival (72%; CI: 0.53-0.96 vs. 42% CI: 0.24-0.71; P-value = 0.07) than patients with a delayed immune reconstitution. Viremic patients had significantly higher transplant-related mortality than nonviremic patients after 1 year (33% CI: 0.15-0.52 vs. 0% CI: 0.05-0.34; P-value = 0.01). Risk factors independently associated with viral replication were receptor pretransplant CMV-positive serostatus (P-value = 0.02) and acquiring CMV-specific T-cell response after 6 weeks post-transplantation (P-value = 0.009). In conclusion, timing of acquiring a positive CMV-specific T-cell immune response after transplantation may identify patients with different risk for viral replication and different clinical outcomes, including survival., (© 2014 Steunstichting ESOT.)

Treatment of infections caused by carbapenemase-producing Enterobacteriaceae (CPE) is currently one of the most important challenges of infectious diseases. The available information is based on in vitro studies, some animal model data and a few case studies and retrospective cohorts; appropriate data are lacking or are very scarce for some old antibiotics that are still occasionally used. Because of the heterogeneity in clinical situations, in specific carbapenemases and in the susceptibility of isolates, individualized treatment decisions must usually be made. Here we review the different antibiotics that might be useful for treating infections caused by CPE., (Copyright © 2014 Elsevier España, S.L.U. All rights reserved.)

The outcome of invasive aspergillosis (IA) continues to be associated with significant attributable mortality, especially in patients with hematological malignancies and in hematopoietic stem cell transplant recipients. In this context, antifungal combined therapy (ACT) has become an emerging strategy against IA. In an attempt to evaluate the benefits of ACT, a large number of experimental studies, clinical series, and randomized trials have been performed, with varying results. In addition, several controlled trials have been registered; however, in most cases, their final results have not been made available. In summary, there is an imbalance between the lack of published evidence regarding the benefits of ACT and its extensive and increasing use in current clinical practice, despite its associated cost. Here, we present a critical analysis of the available information regarding ACT for the treatment of IA as well as the authors' opinion with respect to its use., (© The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: Treatment of multidrug-resistant Acinetobacter baumannii (MDRAB) infection presents a challenge because of the scarcity of available options. Even though combination therapy (CT) is frequently used in clinical practice, data are needed to support its use instead of monotherapy (MT)., Methods: A prospective observational study was conducted in 28 Spanish hospitals. Patients with sepsis caused by MDRAB, defined according to strict criteria, and who received active antibiotic treatment (according to in vitro susceptibility testing) for at least 48 h, were included. The main outcome variable was all-cause 30 day mortality after initiation of targeted therapy. Multivariate analysis, including a propensity score (for receiving CT), was performed by Cox regression., Results: One hundred and one patients were included in the analysis; 68 (67.3%) received MT and 33 (32.7%) received CT. Pneumonia was the most common infection (50.5%), 68.6% of cases being associated with mechanical ventilation. Colistin (67.6%) and carbapenems (14.7%) were the most common drugs used in MT; colistin plus tigecycline (27.3%) and carbapenem plus tigecycline (12.1%) were the most frequent combinations. Crude 30 day mortality was 23.5% and 24.2% for the MT and CT groups, respectively (RR = 1.03; 95% CI 0.49-2.16; P = 0.94). Multivariate analysis of 30 day survival showed no trend towards reduced 30 day mortality with CT (HR = 1.35; 95% CI 0.53-3.44; P = 0.53). Subgroup analysis showed similar results., Conclusions: Our data do not support an association of CT with reduced mortality in MDRAB infections. More data for specific types of infection and combinations are needed., (© The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Objectives: The most frequent adverse events associated with valganciclovir treatment are hematological disturbances such as neutropenia. However, the consequences of neutropenia are unknown. We investigated the clinical impact of neutropenia during CMV preemptive therapy and its relationship with the length of antiviral therapy., Methods: An observational, prospective cohort of 67 solid organ transplant recipients receiving CMV preemptive therapy was studied., Results: Severe neutropenia occurred in 21.8% of the patients at a median of three weeks after initiating antiviral therapy. No association was observed between neutropenia and infection risk in these patients. Liver transplant recipients had 6.7 fold increased risk of neutropenia during CMV therapy compared to kidney transplant recipients (p = 0.012). Patients who developed severe neutropenia received antiviral therapy a median of six days longer than patient who did not (p = 0.457)., Conclusions: Despite the frequency of neutropenia during CMV preemptive therapy, the incidence of infections is not increased. Adjusting the length of preemptive therapy during the episodes of viremia may be recommended, especially in patients with concurrent risk factors for neutropenia such as liver recipients. Further trials are warranted to confirm the safety of this approach., (Copyright © 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.)

Background: Carbapenem-resistant Acinetobacter baumannii (CRAb) is a major source of nosocomial infections in Spain associated with the production of OXA-58-like or OXA-24/40-like β-lactamase enzymes. We analysed the plasmids carrying the bla(OXA-24/40)-like gene in CRAb isolates obtained a decade apart., Methods: The presence of β-lactamases was screened for by PCR (metallo-β-lactamases, carbapenem-hydrolysing class D β-lactamases, GES and KPC) in 101 CRAb isolates obtained in two multicentre studies (GEIH/REIPI-Ab-2000 and GEIH/REIPI-Ab-2010; n = 493 Acinetobacter spp). We analysed the distribution and characterization of the plasmids carrying the bla(OXA-24/40)-like gene and sequenced two plasmids, AbATCC223p (2000) and AbATCC329p (2010) from A. baumannii ATCC 17978 transformants., Results: Acquisition of the bla(OXA-24/40)-like gene was the main mechanism underlying resistance to carbapenems (48.7% in 2000 compared with 51.6% in 2010). This gene was mainly isolated in ST2 A. baumannii strains in both studies, although some novel STs (ST79 and ST80) appeared in 2010. The gene was located in plasmids (8-12 kbp) associated with the repAci2 or repAci2/repGR12 types. The sequences of AbATCC223p (8840 bp) and AbATCC329p (8842 bp) plasmids were similar, particularly regarding the presence of the genes encoding the AbkA/AbkB proteins associated with the toxin/antitoxin system. Moreover, the abkA/abkB gene sequences (>96% identity) were also located in plasmids harbouring the bla(OXA-58)-like gene., Conclusions: The action of OXA-24/40 and OXA-58 β-lactamase-like enzymes represents the main mechanism underlying resistance to carbapenems in Spain in the last decade. AbkA/AbkB proteins in the toxin/antitoxin system may be involved in the successful dissemination of plasmids carrying the bla(OXA-24/40)-like gene, and probably also the bla(OXA-58)-like gene, thus contributing to the plasmid stability., (© The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Invasive fungal infections (IFIs) are becoming more frequent due to the increasing number of patients at risk. Over the last decade, their prognosis has improved with the diagnostic and therapeutic advances, including new antifungals. In the two years, from 2007 to 2009, antifungal consumption increased by 27%, 67 times more than antibacterial consumption, albeit with great differences between hospitals. The scientific evidence of the indications for antifungal prophylaxis and targeted antifungal therapy is strong; however, it is weak for empirical antifungal therapy, which is the most common indication. Antifungals are not harmless, since they are associated with a wide range of adverse effects and drug interactions, favor the development of resistance, contribute to other fungal superinfections and cause significant healthcare spending. Therefore, the question arises whether this extraordinary increase in consumption is justified, whether the use of antifungals is optimal, or whether it is necessary to reconsider the current treatment of IFIs instead., (Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

The antibiotic policy is the set of strategies and activities undertaken to organize the antimicrobial treatment in the hospital, and achieve health outcomes for patients. The basic principles are to be direct evidence-based medicine, local epidemiology and freedom for prescribing physicians. An antibiotic policy is now more necessary than ever for clinical, epidemiological and economic reasons. The Infection Committee is responsible for the antibiotics policy in hospitals. Its functions as an advisory body to the medical directorate are the analysis of the epidemiology of the infections in the center, measures for its prevention and control, improving the appropriate use of antimicrobials, training, and knowledge production. To achieve clinical, environmental and economic policy objectives of antibiotics is not easy. The agreement of hundreds of professionals for recommendations on indications, dosage and duration of antibiotic treatment, based on the best scientific evidence and local guides is complex, but it can be done. The key to this is that the Infection Committee develops antimicrobial stewardship through a multidisciplinary team and professional leadership, and has the institutional support to ensure that the proper use of antimicrobials is a priority for the center, and therefore of each of the services involved, and that the team has the resources for antimicrobial stewardship., (Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

Background: Cytomegalovirus (CMV)-negative recipients of a graft from a CMV-positive donor (D+/R-) are at high risk of CMV disease. Current preventive strategies include universal prophylaxis (UP) and preemptive therapy (PT). However, the best strategy to prevent CMV disease and achieve better long-term outcomes remains a matter of debate., Methods: We analyzed the incidence of CMV disease and long-term outcomes including graft dysfunction and patient mortality at 5 years after transplantation with both preventive strategies. High-risk (D+/R-) kidney and liver transplant recipients from the RESITRA cohort were included., Results: Of 2410 kidney or liver transplant patients, 195 (8.3%) were D+/R-. The final cohort included 58 liver and 102 kidney recipients. UP was given in 92 patients and 68 received PT; 10.9% and 36.8% developed CMV disease, respectively (P < 0.01). The independent risk factors for CMV disease were PT strategy (hazard ratio [HR], 3.30; 95% confidence interval [CI], 1.6-6.9), kidney transplantation (HR, 3.8; 95% CI, 1.4-9.9), and cyclosporine immunosuppression (HR, 2.4; 95% CI, 1.2-4.7). PT strategy was also a risk factor for CMV disease in both liver transplantation (HR, 11.0; 95% CI, 1.2-98.7) and kidney transplantation (HR, 2.7; 95% CI, 1.3-6.0), independently. The development of CMV replication during the first 2 years after transplantation was a risk factor for graft dysfunction at 5 years after transplantation (odds ratio, 3.4; 95% CI, 1.3-9.0). Nevertheless, no significant differences were seen in either graft dysfunction or mortality between the 2 strategies., Conclusions: The study supports the benefit of the UP strategy to prevent CMV disease in D+/R- liver or kidney transplant patients. The development of CMV replication during the first 2 years after transplantation was associated with graft dysfunction at 5 years after transplantation., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Skin and soft tissue infections (SSTI) are relatively common. Although most of these infections are mild, a few are severe, requiring hospital admission for intravenous antimicrobial therapy and, fairly frequently, surgery. These infections can be produced by any microorganism, but the most frequent is Staphylococcus aureus. Traditionally, the bacteria causing community-acquired SSTI have been sensitive to antimicrobial agents but this situation has changed with the dissemination of community-acquired microbial resistance, as has occurred in many countries with the increase in methicillin-resistant S. aureus (MRSA). These changes complicate empirical therapy and increase the risk of monotherapy being insufficient to cover all the diagnostic possibilities of SSTI. Within this epidemiological framework, ceftaroline, because of its activity against MRSA, can be used as empirical monotherapy for SSTI., (Copyright © 2014 Elsevier España, S.L. All rights reserved.)

Objectives: Escherichia coli belonging to clonal group ST131 has emerged as a significant contributor to infection caused by antibiotic-resistant E. coli worldwide. We investigated the risk factors for infections caused by ST131 E. coli and their clinical implications., Methods: One thousand and seventy-seven E. coli isolates were screened for ST131 by molecular methods. Risk factors for ST131 were investigated separately for patients with E. coli producing and not producing extended-spectrum β-lactamases (ESBLs) in the Seville area, Spain. Multivariate analysis using logistic regression was performed. Patients with infections caused by ST131 and non-ST131 isolates were prospectively followed., Results: Independent risk factors for non-ESBL-producing ST131 were female gender (OR: 1.94; 95% CI: 1.07-3.51), diabetes mellitus (OR: 2.17; 95% CI: 1.29-3.67), bedridden status (OR: 7.75; 95% CI: 0.70-85.07) and exposure to amoxicillin/clavulanate (OR: 2.07; 95% CI: 1.08-3.96) or fluoroquinolones (OR: 2.48; 95% CI: 1.41-4.34). For ESBL-producing ST131, male gender was an independent risk factor (OR: 2.20; 95% CI: 0.94-5.11), while healthcare-related acquisition and exposure to any previous antibiotic were protective (OR: 0.30; 95% CI: 0.13-0.71; and OR: 0.43; 95% CI: 0.19-1.00, respectively). Overall, the severity of sepsis, bacteraemia and mortality were similar among ST131 and non-ST131 groups. The presence of typical factors predisposing to E. coli infection was more frequent in non-ESBL-producing ST131 than in controls (76% versus 57.2%, P = 0.005)., Conclusions: Previous use of antibiotics selecting for ST131 isolates was the main modifiable risk factor for infections caused by these isolates. Our results also suggest that the clinical virulence of ST131 is not higher than that of other common E. coli causing infections.

The isolation of Chryseobacterium indologenes as a causative micro-organism in human diseases is rare. Risk factors for infections caused by this pathogen include very young and very old age, indwelling devices, immune suppression and recent use of broad-spectrum antibiotics. Most cases suffer from bacteraemia or nosocomial pneumonia, whilst infection of the central nervous system (CNS) is extremely rare. We present a term-born infant diagnosed prenatally with holoprosencephaly and obstructive hydrocephalus, requiring post-natal ventriculoperitoneal shunt insertion. At 6 weeks of age, he suffered from Escherichia coli meningitis, showing satisfactory clinical response with antimicrobial therapy. Aged 11 months, he suffered from hyper-drainage syndrome, resulting in the removal of the shunt system. He represented 11 days post-operatively, with low-grade fever, irritability and cerebrospinal fluid (CSF) leakage. C. indologenes from CSF was isolated and antimicrobial therapy with ceftazidime and trimethoprim-sulfamethoxazole for 3 weeks resulted in good clinical response. This is the first documented community-acquired CNS infection due to C. indologenes in an infant without concomitant indwelling device or previous antibiotic pressure.

The misuse of antibiotics has been related to increased morbidity, mortality and bacterial resistance. The development of antimicrobial stewardship programmes (ASPs) has been encouraged by scientific societies as an essential measure. An educational, institutionally supported ASP was developed in our tertiary-care centre. Local guidelines on the management of infectious syndromes were created. Antimicrobial prescriptions were chosen arbitrarily weekly and counselling interviews by expert clinicians were carried out, using a paedagogic, non-restrictive methodology. Satisfaction with the interview was assessed using anonymous questionnaires. The appropriateness of antimicrobial prescriptions as well as consumption was assessed prospectively throughout the year. Feedback regarding the correct use of treatments was communicated to each participating department periodically. The improvement in antimicrobial prescription was included among the annual objectives linked to economic incentives in every department. A total of 1206 counselling interviews were carried out during the first year. Fifty-three per cent of antimicrobial prescriptions (176/332) were inappropriate when the programme started. The rate of inappropriate prescriptions continuously declined to 26.4% (107/405) in the fourth trimester (p <0.001; RR = 0.38; 95% CI, 0.23-0.43). Antimicrobial consumption decreased from 1150 defined daily doses (DDDs) per 1000 occupied bed-days in the first trimester to 852 DDDs in the fourth, reflecting a reduction in antimicrobial expenditures of 42%. A total of 352 satisfaction questionnaires were received and 98% described the advice as positive. In conclusion, the implementation of an education-based ASP achieved a significant improvement in all antimicrobial prescriptions in the centre and a reduction in antimicrobial consumption, even when no restrictive measures were implemented. The programme was highly accepted by all prescribers., (© 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.)

Antimicrobial susceptibility testing is essential for guiding the treatment of many types of bacterial infections, especially in the current context of rising rates of antibiotic resistance. The most commonly employed methods rely on the detection of phenotypic resistance by measuring bacterial growth in the presence of the antibiotic being tested. Although these methods are highly sensitive for the detection of resistance, they require that the bacterial pathogen is isolated from the clinical sample before testing and must employ incubation times that are sufficient for differentiating resistant from susceptible isolates. Knowledge regarding the molecular determinants of antibiotic resistance has facilitated the development of novel approaches for the rapid detection of resistance in bacterial pathogens. PCR-based techniques, mass spectrometry, microarrays, microfluidics, cell lysis-based approaches and whole-genome sequencing have all demonstrated the ability to detect resistance in various bacterial species. However, it remains to be determined whether these methods can achieve sufficient sensitivity and specificity compared with standard phenotypic resistance testing to justify their use in routine clinical practice. In the present review, we discuss recent progress in the development of methods for rapid antimicrobial susceptibility testing and highlight the limitations of each approach that still remain be addressed.

We investigated the mechanisms of resistance to carbapenems, aminoglycosides, glycylcyclines, tetracyclines, and quinolones in 90 multiresistant clinical strains of Acinetobacter baumannii isolated from two genetically unrelated A. baumannii clones: clone PFGE-ROC-1 (53 strains producing the OXA-58 β-lactamase enzyme and 18 strains with the OXA-24 β-lactamase) and clone PFGE-HUI-1 (19 strains susceptible to carbapenems). We used real-time reverse transcriptase PCR to correlate antimicrobial resistance (MICs) with expression of genes encoding chromosomal β-lactamases (AmpC and OXA-51), porins (OmpA, CarO, Omp33, Dcap-like, OprB, Omp25, OprC, OprD, and OmpW), and proteins integral to six efflux systems (AdeABC, AdeIJK, AdeFGH, CraA, AbeM, and AmvA). Overexpression of the AdeABC system (level of expression relative to that by A. baumannii ATCC 17978, 30- to 45-fold) was significantly associated with resistance to tigecycline, minocycline, and gentamicin and other biological functions. However, hyperexpression of the AdeIJK efflux pump (level of expression relative to that by A. baumannii ATCC 17978, 8- to 10-fold) was significantly associated only with resistance to tigecycline and minocycline (to which the TetB efflux system also contributed). TetB and TetA(39) efflux pumps were detected in clinical strains and were associated with resistance to tetracyclines and doxycycline. The absence of the AdeABC system and the lack of expression of other mechanisms suggest that tigecycline-resistant strains of the PFGE-HUI-1 clone may be associated with a novel resistance-nodulation-cell efflux pump (decreased MICs in the presence of the inhibitor Phe-Arg β-naphthylamide dihydrochloride) and the TetA(39) system.

Colistin is an old antibiotic which has been used as a therapeutic option for carbapenem- and multidrug-resistant Gram-negative bacteria, like Acinetobacter baumannii. This pathogen produces life-threatening infections, mainly in patients admitted to intensive care units. Rapid detection of resistance to colistin may improve patient outcomes and prevent the spread of resistance. For this purpose, Micromax technology was evaluated in four isogenic A. baumannii strains with known mechanisms of resistance to colistin and in 66 isolates (50 susceptible and 16 resistant). Two parameters were determined, DNA fragmentation and cell wall damage. To assess DNA fragmentation, cells trapped in a microgel were incubated with a lysing solution to remove the cell wall, and the released nucleoids were visualized under fluorescence microscopy. Fragmented DNA was observed as spots that diffuse from the nucleoid. To assess cell wall integrity, cells were incubated with a lysis solution which removes only weakened cell walls, resulting in nucleoid release exclusively in affected cells. A dose-response relationship was demonstrated between colistin concentrations and the percentages of bacteria with DNA fragmentation and cell wall damage, antibiotic effects that were delayed and less frequent in resistant strains. Receiver operating characteristic (ROC) curves demonstrated that both DNA fragmentation and cell wall damage were excellent parameters for identifying resistant strains. Obtaining ≤11% of bacteria with cell wall damage after incubation with 0.5 μg/ml colistin identified resistant strains of A. baumannii with 100% sensitivity and 96% specificity. Results were obtained in 3 h 30 min. This is a simple, rapid, and accurate assay for detecting colistin resistance in A. baumannii, with strong potential value in critical clinical situations.

New approaches of empirical antifungal therapy (EAT) in selected hematological patients with persistent febrile neutropenia (PFN) have been proposed in recent years, but their cost-effectiveness has not been studied. The aim of this study was to compare the cost-effectiveness of two different approaches of EAT in hematological patients with PFN: the diagnosis-driven antifungal therapy (DDAT) approach versus the standard approach of EAT. A decision tree to assess the cost-effectiveness of both approaches was developed. Outcome probabilities and treatment pathways were extrapolated from two studies: a prospective cohort study following the DDAT approach and a randomized clinical trial following the standard approach. Uncertainty was undertaken through sensitivity analyses and Monte Carlo simulation. The average effectiveness and economic advantages in the DDAT approach compared to the standard approach were 2.6% and €5,879 (33%) per PFN episode, respectively. The DDAT was the dominant approach in the 99.5% of the simulations performed with average cost-effectiveness per PFN episode of €32,671 versus €52,479 in the EAT approach. The results were robust over a wide range of variables. The DDAT approach is more cost-effective than the EAT approach in the management of PFN in hematological patients.

Education is a cornerstone of antimicrobial stewardships programs, because 50% of inappropriate antimicrobial prescriptions are a consequence of an imbalance between the high levels of knowledge required for the appropriate use of antibiotics and the scarce training offered to medical specialists. For this reason, programs optimizing antimicrobial (PROA) are essentially based on support and educational activities for prescribers. The educational activities are difficult to evaluate. In our country, the application of educational activities in antimicrobial training programs is very heterogeneous, although it has improved in recent years. We recommend the following educational measures, which are prioritized in order of effectiveness. Interactive educational interventions are the most effective. These are non-compulsory interventions based on real prescriptions in clinical practice and include educational outreach visits, audits and counseling interviews with feedback and multifaceted interventions. Passive educational strategies, with posters, newsletters, and dissemination of guidelines, are only marginally effective in changing antimicrobial prescribing practices and have not shown a sustained effect. These measures need extensive professional involvement and should be combined with more active approaches. Currently, interventions can be enhanced with some teaching tools in electronic format. Both interactive and passive educational measures should be integrated into the PROA and should have institutional support. Finally, we recommend including antimicrobials in the training plans of all clinical specialties., (Copyright © 2013 Elsevier España, S.L. All rights reserved.)

Introduction: A multiresistant CTX-M-15-producing clonal group of Escherichia coli isolates, namely O25b:H4/ST131, has recently emerged in three continents. At this moment, appropriate studies to assess the real prevalence of this successful lineage are still scarce., Methods: In a prospective study in the south of Spain, among all clinical E. coli isolates recovered in Seville during a 30 week period in 2010, ST131 was screened by using PCR for O25b/pabB3/B23 traits. ESBL enzymes were characterized by PCR and sequencing. Genetic relatedness was performed by XbaI PFGE., Results: This clonal group was found to be prevalent (12.5% of all E. coli isolates), and only 37 (6.8% of ST131 isolates) were ESBL producers. Among 25 characterized ESBL-producing ST131 isolates, 96% harbored CTX-M-15. ST131 isolates were more frequently resistant to amoxicillin/clavulanate, aminoglycosides and fluoroquinolones in both ESBL and non-ESBL producers groups. XbaI PFGE performed on 88 ST131 isolates showed three pulsotypes, which included ≥4 isolates each (25% of all typed ST131 isolates), and 11 pulsotypes, which contained 2-3 isolates each. Three of 14 pulsotypes of this clonal group included both nalidixic acid-resistant and susceptible isolates, and five pulsotypes included both ESBL and non-ESBL producers., Conclusions: Our findings suggest that O25b/ST131 is a prevalent clone in our area, and the observed prevalence of ESBL-producers within this clone is similar to that found in the total isolates of this species. Certain pulsotypes among ST131 clone that showed a greater expansion, and ESBL genes acquisition or quinolone resistance could explain part of this prevalence., (Copyright © 2012 Elsevier España, S.L. All rights reserved.)

Objectives: To determine the prevalence of resistance to antimicrobials in Acinetobacter baumannii (A. baumannii) from Spain and to compare it with those obtained in the first national study (GEIH-Ab project 2000)., Methods: A total of 446 isolates of A. baumannii obtained from 43 Spanish hospitals during February-March 2010 were studied. Identification of A. baumannii was confirmed by ARDRA and MALDI-TOF. Susceptibility to 18 antimicrobial agents was determined by microdilution (Clinical and Laboratory Standards Institute, CLSI). The CLSI break-points were used, except for doripenem, rifampin, sulbactam (Societé Française de Microbiologie [SFM] break-points) and tigecycline (European Committee on Antimicrobial Susceptibility Testing [EUCAST] break-points for Enterobacteriaceae)., Results: The percentage of resistant isolates (intermediate susceptible plus resistant) was: > 94% (ceftazidime, piperacillin and ciprofloxacin), 82-86% (carbapenems, tetracycline), 60-70% (tobramycin, sulbactam, gentamicin, doxycycline), 49% (amikacin), 30% (minocycline, rifampin), 24% (tigecycline), and 3% (colistin). These isolates were, in comparison with those of the first study, more resistant (P < .01) to ceftazidime (99% vs 83%), carbapenems (82-86% vs 43-48%), sulbactam (65% vs 53%) and colistin (3% vs 0%), but more susceptible to aminoglycosides (particularly gentamicin: 70% vs 96% of resistant isolates), tetracycline (83% vs 91%) and rifampicin (30% vs 51%)., Conclusion: There is a high prevalence of A. baumannii resistant to antimicrobials, particularly to carbapenems. The resistance to carbapenems, ceftazidime and sulbactam was significantly higher than that observed for isolates from the GEIH-Ab project 2000. The resistance to aminoglycosides, tetracycline and rifampin, however, was significantly decreased., (Copyright © 2012 Elsevier España, S.L. All rights reserved.)

Background: Valganciclovir preemptive therapy guided by the viral load is the current strategy recommended for preventing CMV disease in CMV-seropositive Solid Organ Transplant Recipients (SOTR) at lower risk for developing CMV infection. However, universal viral load cut-off has not been established for initiating therapy., Objectives: Our goal was to define and validate a standardized cut-off determined in plasma by real-time PCR assay for initiating preemptive therapy in this population., Study Design: A prospective cohort study of consecutive cases of CMV-seropositive SOTR was carried out. The cut-off value was determined in a derivation cohort and was validated in the validation cohort. Viral loads were determined using the Quant CMV LightCycler 2.0 real-time PCR System (Roche Applied Science) and results were standardized using the WHO International Standard for human CMV., Results: A viral load of 3983 IU/ml (2600 copies/ml) was established as the optimal cut-off for initiating preemptive therapy in a cohort of 141 patients with 982 tests and validated in a cohort of 252 recipients with a total of 2022 test. This cut-off had a 99.6% NPV indicating that the great majority of patients at lower risk will not develop CMV disease without specific antiviral therapy. The high sensitivity and specificity (89.9% and 88.9%, respectively) and the relatively small numbers of patients with CMV disease confirm that real-time PCR was optimal., Conclusions: We have established a cut-off viral load for starting preemptive therapy for CMV-seropositive SOT recipients. Our results emphasized the importance of a mandatory follow-up protocol for CMV-seropositive patients receiving preemptive treatment., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Clostridium difficile-associated disease (CDAD) is the most common cause of nosocomial diarrhea. Information about CDAD in solid organ transplant (SOT) recipients is scarce. To determine its epidemiology and risk factors, we conducted a cohort study in which 4472 SOT patients were prospectively included in the RESITRA/REIPI (Spanish Research Network for the Study of Infection in Transplantation) database between July 2003 and July 2006. Forty-two episodes of CDAD were diagnosed in 36 patients. The overall incidence was 0.94%. Median onset of infection was 31.5 days (range 6-741); in half the cases, onset occurred during the first month after transplantation. In 26% of cases, there was no previous antibiotic use. Independent risk factors for CDAD using Cox regression analysis were previous use of first- and second-generation cephalosporins (HR 3.68; 95%CI 1.8-7.52; P < 0.001), ganciclovir prophylactic use (HR 3.09; 95%CI 1.44-6.62; P = 0.004) and corticosteroid use before transplantation (HR 2.95; 95%CI 1.1-7.9; P = 0.031). There were no deaths related to CDAD. In summary, the incidence of CDAD in SOT was low, most cases were diagnosed soon after transplantation and the prognosis was good., (© 2012 The Authors. Transplant International © 2012 European Society for Organ Transplantation.)

Cytomegalovirus (CMV) infection remains a major complication in recipients of solid organ transplantation. Based on available evidence, most centers are committed to an aggressive strategy, especially in high-risk patients, consisting of the use of universal prophylaxis in the posttransplantation period of maximum risk (3 months). In seropositive recipients there is no ideal model for prevention, although there is more acceptance in the international community for preemptive therapy. This paper shows the results obtained after analysis of a cohort of 86 patients undergoing heart transplantation in 2005-2011 at the Virgen del Rocío University Hospital, Seville. The 86 patients followed a strategy of preemptive therapy for both high- and low-risk recipients based on the use of antivirals for a variable period of ∼3 weeks when rising antigenemia was detected, determined by polymerase chain reaction above a set threshold. The incidence of CMV disease in our cohort was 4.6%. There are no data available from randomized clinical trials to establish which of the 2 strategies is more effective and safer in these patients, although there is a little experience with preemptive therapy in high-risk patients. Given our positive results and considering the adverse effects of antiviral prophylaxis derivatives, together with the development of resistance and the economic cost, we suggest an individualized prevention strategy at each center., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Purpose: Catheter-related bloodstream infections (CRBSI) are common among patients undergoing long-term hemodialysis (HD) worldwide. The aim of this study was look into the incidence, epidemiology, and risk factors for CRBSI in four medical centers and Spanish dialysis facilities following a common protocol for insertion and management of tunneled hemodialysis catheters (THCs)., Methods: Prospective study including all THCs inserted from September-04 to October-05. Follow-up was from THC insertion to its withdrawal, onset of CRBSI or end of study. Data of all THCs, CRBSI episodes, and catheter complications were collected. A descriptive analysis of CRBSI incidence and etiology and multivariate Cox regression to identify risk factors for CRBSI was performed., Results: A total of 130 THCs in 123 patients were inserted. There were 34 879 catheter-days. Twelve CRBSI in 11 patients with a CRBSI rate of 0.34/1000 catheter-days were recorded. CRBSI was caused by gram-positive coccus in 91.7% of the cases. Vascular cause of renal disease (HR 25.5 CI95% 5.5-117.2), and a previous THC (HR 5.1 CI95% 1.3-19.1) were identified as risk factors for CRBSI. CRBSI were satisfactorily resolved in 83.3% of the cases. Overall mortality was 14.6% (18/123), in two cases (2/11) death occurred within 30 days after CRBSI onset., Conclusions: Although some factors, such as vascular cause of renal disease and previous THC medical history, have been related to the onset of tunneled catheter-related bloodstream infections, the incidence of these bacteremia, mainly produced by gram-positive coccus, is low among hemodialysis patients and the mortality rate is not high.

Infections are frequent and can be severe in recipients of solid organ transplantation. Prevention and treatment are priority objectives of multidisciplinary transplant teams. Interactions between antimicrobials (indicated for prevention and therapy) and immunosuppressants (for preventing rejection) make treatment more complex than in the general population. Co-administration of immunosuppressants and antibiotics can cause harmful interactions, modifying the pharmacokinetic and pharmacodynamic characteristics of both groups of drugs. The loss of the transplanted organ due to reduced levels of immunosuppressants is a unique consequence of the often lethal interactions in this group of patients. By contrast, elevated levels of these drugs cause toxicity, and reduced concentrations of antimicrobial treatment fail to contain the infection. Azoles, rifabutin, protease inhibitors, non-nucleoside reverse transcriptase inhibitors and antimicrobial macrolides all interact with immunosuppressants. In this article, we review interactions between antibiotics and immunosuppressants in order to adopt the most appropriate clinical approach (dosage adjustments, close monitoring of plasma levels and organ function) and determine whether they can be used together with any measure of safety., (Copyright © 2012 Elsevier España S.L. All rights reserved.)

Background: Giving antifungal therapy exclusively to selected patients with persistent febrile neutropenia may avoid over-treatment without increasing mortality. The aim of this study was to validate an innovative diagnostic and therapeutic approach based on assessing patients' risk profile and clinical criteria in order to select those patients requiring antifungal therapy. The efficacy of this approach was compared to that of universal empirical antifungal therapy., Design and Methods: This was a prospective study which included all consecutive adult hematology patients with neutropenia and fever refractory to 5 days of empirical antibacterial therapy admitted to a teaching hospital in Spain over a 2-year period. A diagnostic and therapeutic approach based on clinical criteria and risk profile was applied in order to select patients for antifungal therapy. The sensitivity, specificity and negative predictive value of this approach and also the overall success rate, according to the same criteria of efficacy described in classical clinical trials, were analyzed., Results: Eighty-five episodes were included, 35 of them (41.2%) in patients at high risk of invasive fungal infections. Antifungal therapy was not indicated in 33 episodes (38.8%). The overall incidence of proven and probable invasive fungal infections was 14.1%, all of which occurred in patients who had received empirical antifungal therapy. The 30-day crude mortality rate was 15.3% and the invasive fungal infection-related mortality rate was 2.8% (2/72). The overall success rate following the diagnostic and therapeutic approach was 36.5% compared with 33.9% and 33.7% obtained in the trial by Walsh et al. The sensitivity, specificity and negative predictive value of the study approach were 100%, 52.4% and 100%, respectively., Conclusions: Based on the high negative predictive value of this diagnostic and therapeutic approach in persistent febrile neutropenia patients with hematologic malignancies or patients who have received a hematopoietic stem cell transplant, the approach is useful for identifying patients who are not likely to develop invasive fungal infection and do not, therefore, require antifungal therapy. The effectiveness of the strategy is similar to that of universal empirical antifungal therapy reported in controlled trials.

The antimicrobial agents are unique drugs for several reasons. First, their efficacy is higher than other drugs in terms of reduction of morbidity and mortality. Also, antibiotics are the only group of drugs associated with ecological effects, because their administration may contribute to the emergence and spread of microbial resistance. Finally, they are used by almost all medical specialties. Appropriate use of antimicrobials is very complex because of the important advances in the management of infectious diseases and the spread of antibiotic resistance. Thus, the implementation of programs for optimizing the use of antibiotics in hospitals (called PROA in this document) is necessary. This consensus document defines the objectives of the PROA (namely, to improve the clinical results of patients with infections, to minimise the adverse events associated to the use of antimicrobials including the emergence and spread of antibiotic resistance, and to ensure the use of the most cost-efficacious treatments), and provides recommendations for the implementation of these programs in Spanish hospitals. The key aspects of the recommendations are as follows. Multidisciplinary antibiotic teams should be formed, under the auspices of the Infection Committees. The PROA need to be considered as part of institutional programs and the strategic objectives of the hospital. The PROA should include specific objectives based on measurable indicators, and activities aimed at improving the use of antimicrobials, mainly through educational activities and interventions based more on training activities directed to prescribers than just on restrictive measures., (Copyright © 2011 Elsevier España, S.L. All rights reserved.)

Cytomegalovirus infection remains a major complication of solid organ transplantation. In 2005 the Spanish Transplantation Infection Study Group (GESITRA) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) developed consensus guidelines for the prevention and treatment of CMV infection in solid organ transplant recipients. Since then, numerous publications have clarified or questioned the aspects covered in the previous document. These aspects include the situations and populations who must receive prophylaxis and its duration, the selection of the best diagnosis and monitoring technique and the best therapeutic strategy. For these reasons, we have developed new consensus guidelines to include the latest recommendations on post-transplant CMV management based on new evidence available., (Copyright © 2011 Elsevier España, S.L. All rights reserved.)

CMV prevention strategies in liver transplant recipients should be stratified according to serological status. In donor (D)-/recipient (R)- combinations, no prophylaxis or preemptive therapy is recommended. In the remaining combinations, the most widely used strategies are universal prophylaxis and preemptive therapy. Both strategies are effective compared with placebo but have not been compared with each other in well-designed clinical trials. Preemptive therapy is the preferred strategy in low-risk patients while prophylaxis is the most widely used option in those at high-risk. Delayed CMV disease is an adverse consequence of universal prophylaxis. Prolongation of prophylaxis from 100 to 200 days does not reduce the incidence of CMV disease. CMV-specific cell mediated immunity, facilitated by preemptive therapy and delayed by prophylaxis, has a therapeutic effect by reducing CMV replication. The drug of choice in both strategies is valganciclovir but the duration and dose differ. When preemptive therapy is used, viremia monitoring is required for the first 4 months. The technique of choice is quantitative polymerase chain reaction. Given the lack of conclusive data, the choice of one or other strategy in these patients should be individualized in each patient and center according to the available resources and possibilities of follow-up., (Copyright © 2011 Elsevier España S.L. All rights reserved.)