Results of phase 2 randomized multi-center study to evaluate the safety and efficacy of infusion of memory T cells as adoptive therapy in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia and/or lymphopenia (RELEASE NCT04578210)

BACKGROUND AIMS

There are currently no effective anti-viral treatments for coronavirus disease 2019 (COVID-19)-hospitalized patients with hypoxemia. Lymphopenia is a biomarker of disease severity usually present in patients who are hospitalized. Approaches to increasing lymphocytes exerting an anti-viral effect must be considered to treat these patients. Following our phase 1 study, we performed a phase 2 randomized multicenter clinical trial in which we evaluated the efficacy of the infusion of allogeneic off-the-shelf CD45RA- memory T cells containing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cells from convalescent donors plus the standard of care (SoC) versus just the SoC treatment.

METHODS

Eighty-four patients were enrolled in three Spanish centers. The patients were randomized into the infusion of 1 × 106/kg CD45RA- memory T cells or the SoC. We selected four unvaccinated donors based on the expression of interferon gamma SARS-CoV-2-specific response within the CD45RA- memory T cells and the most frequent human leukocyte antigen typing in the Spanish population.

RESULTS

We analyzed data from 81 patients. The primary outcome for recovery, defined as the proportion of participants in each group with normalization of fever, oxygen saturation sustained for at least 24 hours and lymphopenia recovery through day 14 or at discharge, was met for the experimental arm. We also observed faster lymphocyte recovery in the experimental group. We did not observe any treatment-related adverse events.

CONCLUSIONS

Adoptive cell therapy with off-the-shelf CD45RA- memory T cells containing SAR-CoV-2-specific T cells is safe, effective and accelerates lymphocyte recovery of patients with COVID-19 pneumonia and/or lymphopenia.

TRIAL REGISTRATION

NCT04578210.

Treatment and prevention of monkeypox

Monkeypox is a zoonosis that is spread mainly through direct contact with fluids and skin lesions of infected people with vesicles still active. Although the virus was isolated for the first time in 1958 and the first human case was identified in a child in 1970, in the Democratic Republic of the Congo, the disease has progressively increased its incidence in Africa reaching in May 2022 sustained transmission outside this continent. As it is a newly introduced virus in our health system, it is necessary to learn the epidemiological pattern in a different environment from that of traditionally endemic areas and to know the available antiviral treatments, as well as the prophylactic measures that could be considered, knowing that as a virus emerging in our regions, scientific evidence is still limited. There are antivirals that have been shown, in animal models, to effectively combat the disease with very good clinical tolerance. This disease has also forced us to review the characteristics of smallpox vaccines, because they have shown a protective effect against monkeypox. For this reason, it is important to have a document that compiles all the scientific information published in this regard.

[Treatment and prevention of monkeypox]

Monkeypox is a zoonosis that is spread mainly through direct contact with fluids and skin lesions of infected people with vesicles still active. Although the virus was isolated for the first time in 1958 and the first human case was identified in a child in 1970, in the Democratic Republic of the Congo, the disease has progressively increased its incidence in Africa reaching in May 2022 sustained transmission outside this continent. As it is a newly introduced virus in our health system, it is necessary to learn the epidemiological pattern in a different environment from that of traditionally endemic areas and to know the available antiviral treatments, as well as the prophylactic measures that could be considered, knowing that as a virus emerging in our regions, scientific evidence is still limited. There are antivirals that have been shown, in animal models, to effectively combat the disease with very good clinical tolerance. This disease has also forced us to review the characteristics of smallpox vaccines, because they have shown a protective effect against monkeypox. For this reason, it is important to have a document that compiles all the scientific information published in this regard.

Phase I dose-escalation single centre clinical trial to evaluate the safety of infusion of memory T cells as adoptive therapy in COVID-19 (RELEASE)

BACKGROUND

Effective treatments are still needed to reduce the severity of symptoms, time of hospitalization, and mortality of COVID-19. SARS-CoV-2 specific memory T-lymphocytes obtained from convalescent donors recovered can be used as passive cell immunotherapy.

METHODS

Between September and November 2020 a phase 1, dose-escalation, single centre clinical trial was conducted to evaluate the safety and feasibility of the infusion of CD45RA^- memory T cells containing SARS-CoV-2 specific T cells as adoptive cell therapy against moderate/severe cases of COVID-19. Nine participants with pneumonia and/or lymphopenia and with at least one human leukocyte antigen (HLA) match with the donor were infused. The first three subjects received the lowest dose (1 × 10⁵ cells/kg), the next three received the intermediate dose (5 × 10⁵ cells/kg) and the last three received the highest dose (1 × 10⁶ cells/kg) of CD45RA^- memory T cells. Clinicaltrials.gov registration: NCT04578210.

FINDINGS

All participants' clinical status measured by National Early Warning Score (NEWS) and 7-category point ordinal scales showed improvement six days after infusion. No serious adverse events were reported. Inflammatory parameters were stabilised post-infusion and the participants showed lymphocyte recovery two weeks after the procedure. Donor microchimerism was observed at least for three weeks after infusion in all patients.

INTERPRETATION

This study provides preliminary evidence supporting the idea that treatment of COVID-19 patients with moderate/severe symptoms using convalescent CD45RA^- memory T cells is feasible and safe.

FUNDING

Clinical Trial supported by Spanish Clinical Research Network PT17/0017/0013. Co-funded by European Regional Development Fund/European Social Fund. CRIS CANCER Foundation Grant to AP-M and Agencia Valenciana de Innovación Grant AVI-GVA COVID-19-68 to BS.

SARS-CoV-2-Specific Memory T Lymphocytes From COVID-19 Convalescent Donors: Identification, Biobanking, and Large-Scale Production for Adoptive Cell Therapy

Syndrome coronavirus 2 (SARS-CoV-2) pandemic is causing a second outbreak significantly delaying the hope for the virus’ complete eradication. In the absence of effective vaccines, we need effective treatments with low adverse effects that can treat hospitalized patients with COVID-19 disease. In this study, we determined the existence of SARS-CoV-2-specific T cells within CD45RA^– memory T cells in the blood of convalescent donors. Memory T cells can respond quickly to infection and provide long-term immune protection to reduce the severity of COVID-19 symptoms. Also, CD45RA^– memory T cells confer protection from other pathogens encountered by the donors throughout their life. It is of vital importance to resolve other secondary infections that usually develop in patients hospitalized with COVID-19. We found SARS-CoV-2-specific memory T cells in all of the CD45RA^– subsets (CD3⁺, CD4⁺, and CD8⁺) and in the central memory and effector memory subpopulations. The procedure for obtaining these cells is feasible, easy to implement for small-scale manufacture, quick and cost-effective, involves minimal manipulation, and has no GMP requirements. This biobank of specific SARS-CoV-2 memory T cells would be immediately available “off-the-shelf” to treat moderate/severe cases of COVID-19, thereby increasing the therapeutic options available for these patients.

Absence of IgG antibodies among high-risk contacts of two confirmed cases of Crimean-Congo haemorrhagic fever in the autonomous region of Madrid (Spain)

Crimean-Congo haemorrhagic fever (CCHF) is a widely distributed tick-borne disease. In Spain, the disease has emerged as outbreak associated with high-risk exposures. Our goal was to evaluate the prevalence of antibodies against the CCHF virus (CCHFV) in high-risk contacts. A cross-sectional study was conducted. Three hundred eighty-six high-risk contacts were identified comprising family contacts and hospital workers who had attended the cases. Fifty-seven cases with closer exposure were selected. However, forty-nine cases participated in the study. IgG antibodies were detected by immunoenzymatic techniques. All determinations tested negative for anti-CCHFV IgG antibodies. Most of the responders were women (73.5%), and belong to the intensive care department (53.1%). In relation to other possible sources of exposures, 18.4% travelled to countries with CCHF transmission risk. No CCHF positivity was recorded among selected high-risk contacts. This highlights the importance of standard precautions which might have protected healthcare workers and care providers from CCHF infection.

Compassionate Use of Remdesivir for Patients with Severe Covid-19

BACKGROUND

Remdesivir, a nucleotide analogue prodrug that inhibits viral RNA polymerases, has shown in vitro activity against SARS-CoV-2.

METHODS

We provided remdesivir on a compassionate-use basis to patients hospitalized with Covid-19, the illness caused by infection with SARS-CoV-2. Patients were those with confirmed SARS-CoV-2 infection who had an oxygen saturation of 94% or less while they were breathing ambient air or who were receiving oxygen support. Patients received a 10-day course of remdesivir, consisting of 200 mg administered intravenously on day 1, followed by 100 mg daily for the remaining 9 days of treatment. This report is based on data from patients who received remdesivir during the period from January 25, 2020, through March 7, 2020, and have clinical data for at least 1 subsequent day.

RESULTS

Of the 61 patients who received at least one dose of remdesivir, data from 8 could not be analyzed (including 7 patients with no post-treatment data and 1 with a dosing error). Of the 53 patients whose data were analyzed, 22 were in the United States, 22 in Europe or Canada, and 9 in Japan. At baseline, 30 patients (57%) were receiving mechanical ventilation and 4 (8%) were receiving extracorporeal membrane oxygenation. During a median follow-up of 18 days, 36 patients (68%) had an improvement in oxygen-support class, including 17 of 30 patients (57%) receiving mechanical ventilation who were extubated. A total of 25 patients (47%) were discharged, and 7 patients (13%) died; mortality was 18% (6 of 34) among patients receiving invasive ventilation and 5% (1 of 19) among those not receiving invasive ventilation.

CONCLUSIONS

In this cohort of patients hospitalized for severe Covid-19 who were treated with compassionate-use remdesivir, clinical improvement was observed in 36 of 53 patients (68%). Measurement of efficacy will require ongoing randomized, placebo-controlled trials of remdesivir therapy. (Funded by Gilead Sciences.).

COVID-19: Key Concepts for the Surgeon

In view of the current pandemic by SARS-CoV-2 it deems essential to understand the key concepts about the infection: its epidemiological origin, presentation, clinical course, diagnosis and treatment (still experimental in many cases). The knowledge about the virus is still limited, but as the pandemic progresses and the physiopathology of the disease is understood, new evidence is being massively published. Surgical specialists are facing an unprecedented situation: they must collaborate in the ER or medical wards attending these patients, while still needing to make decisions about surgical patients with probable COVID-19. The present narrative review aims to summarize the most relevant aspects and synthetize concepts on COVID-19 for surgeons.

COVID-19: Key Concepts for the Surgeon

In view of the current pandemic by SARS-CoV-2 it deems essential to understand the key concepts about the infection: its epidemiological origin, presentation, clinical course, diagnosis and treatment (still experimental in many cases). The knowledge about the virus is still limited, but as the pandemic progresses and the physiopathology of the disease is understood, new evidence is being massively published. Surgical specialists are facing an unprecedented situation: they must collaborate in the ER or medical wards attending these patients, while still needing to make decisions about surgical patients with probable COVID-19. The present narrative review aims to summarize the most relevant aspects and synthetize concepts on COVID-19 for surgeons.

Broad Neutralizing Activity Against Ebolaviruses Lacking the Mucin-Like Domain in Convalescent Plasma Specimens From Patients With Ebola Virus Disease

Background

In Ebola virus (EBOV) infection, the specific neutralizing activity of convalescent plasma against other members of the Ebolavirus genus has not been extensively analyzed.

Methods

We measured the neutralizing activity in plasma from 3 survivors of the recent outbreak due to the Makona variant of EBOV and tested its neutralizing potency against other variants of EBOV (ie, Mayinga and Kikwit) and against Sudan virus (SUDV), Bundibugyo virus (BDBV), and Reston virus (RESTV), using a glycoprotein (GP)-pseudotyped lentiviral system both with full-length GP and in vitro-cleaved GP (GPCL).

Results

Convalescent plasma specimens from survivors of EBOV infection showed low neutralizing activity against full-length GPs of SUDV, BDBV, RESTV, and EBOV variants Mayinga and Kikwit. However, broad and potent neutralizing activity was observed against the GPCL forms of SUDV, BDBV, and RESTV.

Discussion

Removal of the mucin-like domain and glycan cap from the GP of members of the Ebolavirus genus presumably exposes conserved epitopes in or in the vicinity of the receptor binding site and internal fusion loop that are readily amenable to neutralization. These types of broad neutralizing antibodies could be induced by using immunogens mimicking GPCL.

Epidemiology and natural history of cutaneous squamous cell carcinoma in recessive dystrophic epidermolysis bullosa patients: 20 years' experience of a reference centre in Spain

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is the leading cause of death in patients with recessive dystrophic epidermolysis bullosa (RDEB). We provide the management and prognosis of cSCC in RDEB patients at a Spanish reference center.

MATERIALS AND METHODS

We retrospectively included patients with RDEB attended in La Paz University Hospital from November 1988 to October 2018.

RESULTS

Fourteen patients developed at least one cSCC. Tumors were predominantly well differentiated. Nearly half of the tumors have recurred. Median time to first recurrence was 23.4 months (95% CI: 17.2-29.5). Five patients have developed distant metastases. Median overall survival (mOS) was 136.5 months since the diagnosis of the first cSCC (95% CI: 30.6-242.3). When distant metastases occurred, mOS was 6.78 months (95% CI: 1.94-11.61).

CONCLUSIONS

cSCC is a life-threatening complication of RDEB patients. Although tumors are usually well differentiated, they tend to relapse. This is the first Spanish report of cSCC arising in RDEB patients.

Evidence for Previously Unidentified Sexual Transmission of Protozoan Parasites

Knowing the mode of transmission of a disease can affect its control and prevention. Here, we identify 5 protozoan parasites with demonstrated presence in seminal fluid, only 1 of which has been identified as a sexually transmitted disease among humans.

Therapeutic management of Crimean-Congo haemorrhagic fever

Crimean-Congo haemorrhagic fever has been reported in more than 30 countries in Africa, Asia, the Middle East and Eastern Europe, with an increasing incidence in recent years, especially in Europe. Because no specific treatments have demonstrated efficacy, supportive treatment is essential, as well as the provision of a centre with the appropriate means to guarantee the safety of its healthcare professionals. Laboratory monitoring of thrombocytopenia, severe coagulopathy or liver failure is of critical importance. Patients with Crimean-Congo haemorrhagic fever should be admitted to High Level Isolation Units where appropriate biocontainment procedures can prevent nosocomial transmission through infected fluids or accidents with contaminated material. In case of high-risk exposures, early administration of ribavirin should be considered.

Therapeutic management of Crimean-Congo haemorrhagic fever

Crimean-Congo haemorrhagic fever has been reported in more than 30 countries in Africa, Asia, the Middle East and Eastern Europe, with an increasing incidence in recent years, especially in Europe. Because no specific treatments have demonstrated efficacy, supportive treatment is essential, as well as the provision of a centre with the appropriate means to guarantee the safety of its healthcare professionals. Laboratory monitoring of thrombocytopenia, severe coagulopathy or liver failure is of critical importance. Patients with Crimean-Congo haemorrhagic fever should be admitted to High Level Isolation Units where appropriate biocontainment procedures can prevent nosocomial transmission through infected fluids or accidents with contaminated material. In case of high-risk exposures, early administration of ribavirin should be considered.

Predictors of outcome in patients with severe sepsis or septic shock due to extended-spectrum β-lactamase-producing Enterobacteriaceae

PURPOSE

There are few data in the literature regarding sepsis or septic shock due to extended-spectrum β-lactamases (ESBL)-producing Enterobacteriaceae (E). The aim of this study was to assess predictors of outcome in septic patients with bloodstream infection (BSI) caused by ESBL-E.

METHODS

Patients with severe sepsis or septic shock and BSI due to ESBL-E were selected from the INCREMENT database. The primary endpoint of the study was the evaluation of predictors of outcome after 30 days from development of severe sepsis or septic shock due to ESBL-E infection. Three cohorts were created for analysis: global, empirical-therapy and targeted-therapy cohorts.

RESULTS

367 septic patients were analysed. Overall mortality was 43.9% at 30 days. Escherichia coli (62.4%) and Klebsiella pneumoniae (27.2%) were the most frequent isolates. β-lactam/β-lactamase inhibitor (BLBLI) combinations were the most empirically used drug (43.6%), followed by carbapenems (29.4%). Empirical therapy was active in vitro in 249 (67.8%) patients, and escalation of antibiotic therapy was reported in 287 (78.2%) patients. Cox regression analysis showed that age, Charlson Comorbidity Index, McCabe classification, Pitt bacteremia score, abdominal source of infection and escalation of antibiotic therapy were independently associated with 30-day mortality. No differences in survival were reported in patients treated with BLBLI combinations or carbapenems in empirical or definitive therapy.

CONCLUSIONS

BSI due to ESBL-E in patients who developed severe sepsis or septic shock was associated with high 30-day mortality. Comorbidities, severity scores, source of infection and antibiotic therapy escalation were important determinants of unfavorable outcome.

Autochthonous Crimean-Congo Hemorrhagic Fever in Spain

Crimean-Congo hemorrhagic fever (CCHF) is a widely distributed, viral, tickborne disease. In Europe, cases have been reported only in the southeastern part of the continent. We report two autochthonous cases in Spain. The index patient acquired the disease through a tick bite in the province of Ávila - 300 km away from the province of Cáceres, where viral RNA from ticks was amplified in 2010. The second patient was a nurse who became infected while caring for the index patient. Both were infected with the African 3 lineage of this virus. (Funded by Red de Investigación Cooperativa en Enfermedades Tropicales [RICET] and Efficient Response to Highly Dangerous and Emerging Pathogens at EU [European Union] Level [EMERGE].).

Ceftazidime-Avibactam as Salvage Therapy for Infections Caused by Carbapenem-Resistant Organisms

Ceftazidime-avibactam (CAZ-AVI) is a recently approved β-lactam-β-lactamase inhibitor combination with the potential to treat serious infections caused by carbapenem-resistant organisms. Few patients with such infections were included in the CAZ-AVI clinical trials, and clinical experience is lacking. We present a case series of patients with infections caused by carbapenem-resistant Enterobacteriaceae (CRE) or Pseudomonas aeruginosa (CRPa) who were treated with CAZ-AVI salvage therapy on a compassionate-use basis. Physicians who had prescribed CAZ-AVI completed a case report form. We used descriptive statistics to summarize patient characteristics and treatment outcomes. We used the Wilcoxon rank sum test and Fisher's exact test to compare patients by treatment outcome. The sample included 36 patients infected with CRE and two with CRPa. The most common infections were intra-abdominal. Physicians categorized 60.5% of patients as having life-threatening infections. All but two patients received other antibiotics before CAZ-AVI, for a median of 13 days. The median duration of CAZ-AVI treatment was 16 days. Twenty-five patients (65.8%) concurrently received other antibiotics to which their pathogen was nonresistant in vitro Twenty-eight patients (73.7%, 95% confidence interval [CI], 56.9 to 86.6%) experienced clinical and/or microbiological cure. Five patients (20.8%) with documented microbiological cure died, whereas 10 patients (71.4%) with no documented microbiological cure died (P = 0.01). In three-quarters of cases, CAZ-AVI (alone or combined with other antibiotics) cured infections caused by carbapenem-resistant organisms, 95% of which had failed previous therapy. Microbiological cure was associated with improved survival. CAZ-AVI shows promising clinical results for infections for which treatment options are limited.

Ertapenem for the treatment of bloodstream infections due to ESBL-producing Enterobacteriaceae: a multinational pre-registered cohort study

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.

Impact of virulence genes on sepsis severity and survival in Escherichia coli bacteremia

Extraintestinal pathogenic Escherichia coli (ExPEC) are a frequent cause of bacteremia and sepsis, but the role of ExPEC genetic virulence factors (VFs) in sepsis development and outcome is ill-defined. Prospective study including 120 adult patients with E. coli bacteremia to investigate the impact of bacterial and host factors on sepsis severity and mortality. Patients' clinical and demographic data were registered. Phylogenetic background of E. coli isolates was analyzed by SNP pyrosequencing and VFs by PCR. The E. coli isolates presented an epidemic population structure with 6 dominant clones making up to half of the isolates. VF gene profiles were highly diverse. Multivariate analysis for sepsis severity showed that the presence of cnf and blaTEM genes increased the risk of severe illness by 6.75 (95% confidence interval [CI] 1.79-24.71) and 2.59 (95% CI 1.04-6.43) times respectively, while each point in the Pitt score increased the risk by 1.34 (95% CI 1.02-1.76) times. Multivariate analysis for mortality showed that active chemotherapy (OR 17.87, 95% CI 3.35-95.45), McCabe-Jackson Index (OR for rapidly fatal category 120.15, 95% CI 4.19-3446.23), Pitt index (OR 1.78, 95% CI 1.25-2.56) and presence of fyuA gene (OR 8.05, 95% CI 1.37-47.12) were associated to increased mortality while the presence of P fimbriae genes had a protective role (OR 0.094, 95%IC 0.018-0.494). Bacteremic E. coli had a high diversity of genetic backgrounds and VF gene profiles. Bacterial VFs and host determinants had an impact on disease evolution and mortality.

[Ebola virus disease: Update]

The first known Ebola outbreak occurred in 1976. Since then, 24 limited outbreaks had been reported in Central Africa, but never affecting more than 425 persons. The current outbreak in Western Africa is the largest in history with 28,220 reported cases and 11,291 deaths. The magnitude of the epidemic has caused worldwide alarm. For the first time, evacuated patients were treated outside Africa, and secondary cases have occurred in Spain and the United States. Since the start of the current epidemic, our knowledge about the epidemiology, clinical picture, laboratory findings, and virology of Ebola virus disease has considerably expanded. For the first time, experimental treatment has been tried, and there have been spectacular advances in vaccine development. A review is presented of these advances in the knowledge of Ebola virus disease.

Uncoupling between core genome and virulome in extraintestinal pathogenic Escherichia coli

Extraintestinal pathogenic Escherichia coli (ExPEC) are among the most frequently isolated bacterial pathogens in hospitals. They are considered opportunistic pathogens and are found mostly in urinary and bloodstream infections. They are genetically diverse, and many studies have sought associations between genotypes or virulence genes and infection site, severity, or outcome, with varied, often contradictory, results. To understand these difficulties, we have analyzed the diversity patterns in the core genomes and virulomes of more than 500 ExPEC isolates from 5 different collections. The core genome was analyzed using a multilocus sequence type-based single-nucleotide polymorphism (SNP) pyrosequencing approach, while the virulence gene content (the virulome) was studied by polymerase chain reaction detection of 25 representative genes. SNP typing showed a similar population structure in the different collections: half of the isolates belong to a few sequence types (5 to 8), while the other half is composed of a large diversity of sequence types that are found once or twice. Sampling analysis by rarefaction plots of SNP profiles showed saturation curves indicative of a limited diversity. Contrary to this, the virulome shows an extremely high diversity, with almost as many gene profiles as isolates, and linear, nonsaturating, rarefaction plots, even within sequence types. These data show that genetic exchange rates are very heterogeneous along the chromosome, being much higher in the virulome fraction of the genome than in the core genome.

How to assist clinicians in improving antimicrobial prescribing: tools and interventions provided by stewardship programs

In the last decade, there has been an exponential increase in the microorganisms resistant to antimicrobials and a significant increase in the cost of these types of drugs. This phenomenon has increased interest in the development of interventions for counseling on and control of the use of antimicrobials, referred to as stewardship programs. In this article we review, from various points of view, the tools that have been developed with this purpose. First, we highlight the value of locally adapted guidelines and clinical pathways as an essential part of the operational process. Then we emphasize the importance of the relationship between microbiologists and clinicians for the accurate transmission of the information provided by blood cultures to make the most appropriate choice of antimicrobial for the patient's treatment. We also review the computerized tools that have facilitated the correct use of antimicrobials according to the controls established by the departments of pharmacy. Based on the previous tools, some programs based on "bedside recommendations" provided by multidisciplinary teams have been developed for optimizing the rational use of antimicrobials (PROA programs). Finally, we comment on the peculiarities of the programs targeting antifungals that have been developed in recent years.

Bacteraemia due to meticillin-resistant Staphylococcus aureus carrying the mecC gene in a patient with urothelial carcinoma

We present a case of bacteraemia due to meticillin-resistant Staphylococcus aureus (MRSA) carrying the mecC gene. The susceptibility to meticillin of Staphylococcus aureus was investigated directly from one blood culture bottle using GenomEra MRSA/SA (Abacus Diagnostica Oy) test. This test identified S. aureus but the presence of the mecA gene result was negative, and the isolate was reported as meticillin-sensitive Staphylococcus aureus (MSSA). Susceptibility studies were done using VITEK 2 AST-P588 susceptibility cards (bioMérieux). The strain was identified as MRSA by the VITEK 2 system, although oxacillin MIC was low (0.5 µg ml(-1)). In view of these results, the isolate was tested for the presence of the mecC gene by a specific PCR and was verified as MRSA carrying mecC. The emergence of this new mecA homologue could have important consequences for the detection of MRSA when routine PCR methods are used as an identification method or provisional detection of MRSA, as in the case reported in this article, because S. aureus carrying the mecC gene will be wrongly diagnosed as meticillin susceptible. Negative results must be interpreted with caution and should be followed by conventional culture, and antimicrobial susceptibility testing or detection of mecC gene by a specific PCR.