Teresa Peláez

Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Madrid, Spain

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Publications (109)443.11 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Most current guidelines do not recommend systematic screening with echocardiography in patients with candidemia, as Candida infective endocarditis (CIE) is considered an uncommon disease. During the study period, we recommended echocardiography systematically to all candidemic patients that did not have contraindications and accepted to participate in the study. We intended to assess the incidence of unrecognized CIE in adult patients with candidemia. Our institution is a tertiary teaching hospital in which we follow all patients with candidemia. From January 2007 to October 2012, echocardiography was systematically recommended to suitable candidates. We recorded 263 cases of candidemia in adult patients. Echocardiography was not performed in 76 of these patients for the following reasons: patients had died when blood cultures became positive (17), patients were critically or terminally ill (38), or the patient or physician refused the procedure (21). The remaining 187 patients constitute the basis of this report. CIE was diagnosed in 11 cases (4.2 % of the whole candidemic population and 5.9 % of the population with echocardiographic study). The results of transthoracic echocardiography (TTE) suggested infective endocarditis (IE) in 5/172 patients (2.9 %), and the result of transesophageal echocardiography (TEE) was positive in 10/87 (11.5 %). Among 11 confirmed cases of CIE, the disease was clinically unsuspected in three patients. At least 4.2 % of all candidemic patients have CIE. CIE is frequently clinically unsuspected and echocardiography is required to demonstrate a high proportion of cases.
    European Journal of Clinical Microbiology 05/2015; DOI:10.1007/s10096-015-2384-z · 2.54 Impact Factor
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    ABSTRACT: Clostridium difficile infection (CDI) is the leading cause of hospital-acquired diarrhoea in developed countries. Metronidazole and vancomycin are the mainstay of treatment, although they are associated with treatment failure and recurrence. Novel agents have emerged to address these shortcomings. We investigated the in vitro activity of a novel agent, surotomycin (formerly CB-183,315), and seven other antimicrobial agents against clinical C. difficile isolates. Antimicrobial susceptibility to surotomycin, fidaxomicin, metronidazole, vancomycin, clindamycin, rifaximin, moxifloxacin and tigecycline was determined for 100 contemporary clinical isolates of C. difficile collected in 2013. MICs were determined by agar dilution according to CLSI procedures. In addition, 10 strains with reduced susceptibility to metronidazole (n = 6) and vancomycin (n = 4) were also tested. Strains were PCR ribotyped. The MICs of surotomycin for the 100 isolates ranged from ≤0.06 to 2 mg/L, with a geometric mean (GM) of 0.31 mg/L and an MIC50/90 of 0.25/0.5 mg/L. The MIC range of surotomycin was 0.25-1 mg/L (GM = 0.45 mg/L) for isolates with reduced metronidazole susceptibility and 0.125-0.5 mg/L (GM = 0.25 mg/L) for isolates with reduced vancomycin susceptibility. The three most common ribotypes were 001 (31.0%), 014/020 (17.0%) and 078/126 (17.0%). Ribotype 014/020 exhibited the lowest MICs of surotomycin (GM = 0.22 mg/L); the highest MICs were for ribotype 078/126 (GM = 0.72 mg/L). Surotomycin exhibited potent in vitro activity against all the isolates tested, including those with elevated metronidazole and vancomycin MICs. The potential role of this agent in the treatment of CDI requires further clinical evaluation. © 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.
    Journal of Antimicrobial Chemotherapy 04/2015; DOI:10.1093/jac/dkv092 · 5.44 Impact Factor
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    ABSTRACT: We report the first isolation of a voriconazole-resistant Aspergillus fumigatus strain harbouring the azole resistance mechanism TR46/Y121F/T289A, recovered from an azole-naive patient in Spain with chronic obstructive pulmonary disease. This new finding in Spain suggests the spread of this resistance mechanism and reinforces the need for antifungal susceptibility surveillance.
    04/2015; DOI:10.1016/j.nmni.2015.04.005
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    ABSTRACT: The use of molecular identification techniques has revealed an increasing number of new species within Aspergillus section Terrei. We phenotyped a set of 26 clinical isolates that showed genetic differences with A. terreus sensu stricto by analyzing sequences from PCR amplified β-tubulin and calmodulin genes and the ITS region. Since the isolates were phylogenetically and morphologically different from all the Aspergillus section Terrei members, they are described here as a new species, Aspergillus citrinoterreus, so named because it produces a diffusible yellowish pigment in agar. A. citrinoterreus isolates were significantly more susceptible to itraconazole, voriconazole, and posaconazole than A. terreus sensu stricto isolates; in contrast, amphotericin B showed high MICs for both species. A. citrinoterreus was found in clinical samples from patients with proven or probable invasive aspergillosis and colonized patients, none of whom had hematological malignancies as predisposing conditions. However, they did have other underlying conditions such as chronic obstructive pulmonary disease, cirrhosis, and cancer, or had received a solid organ transplant, and presented not only with invasive pulmonary aspergillosis but also with mediastinitis. A. citrinoterreus isolates were detected for the first time in 2002. In all cases of invasive aspergillosis, A. citrinoterreus was found to be a copathogen, mostly with A. fumigatus. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
    Journal of Clinical Microbiology 02/2015; 53(2):611-617. DOI:10.1128/JCM.03088-14 · 4.23 Impact Factor
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    ABSTRACT: In the absence of histopathology studies of lung biopsies, the bronchoalveolar lavage (BAL) sample is preferred for the diagnosis of invasive pulmonary aspergillosis. Isolation of Aspergillus fumigatus from sputum and bronchial secretion samples are commonly interpreted as colonization or laboratory contamination, particularly in nonneutropenic patients. We studied if sputum/bronchial secretions and BAL samples are equally useful for the diagnosis of invasive pulmonary aspergillosis. We retrospectively selected 14 patients with proven (n = 1) or probable (n = 13) invasive pulmonary aspergillosis from whose samples A. fumigatus had been simultaneously isolated in BAL and sputum/bronchial secretions between 2006 and 2012. The isolates were identified by sequencing the β-tubulin gene and genotyped using the STRAf assay. Matches between BAL and sputum/bronchial secretions were observed in patients with identical genotypes in BAL and sputum/bronchial secretions. All patients had clinically suspected pneumonia, before the diagnosis of invasive pulmonary aspergillosis. The sample from which A. fumigatus was initially isolated was collected as a result of the presence of fever (50%), abnormal radiological findings (100%), and/or pneumonia that did not respond to antibiotics (36%). The underlying conditions varied, although the most common predisposing factors were hematological malignancies (21.5%) and COPD (43%). In 13 of the 14 patients (93%), we found matching genotypes in the BAL and the sputum/bronchial secretion samples. Genotyping showed that samples of sputum or bronchial secretions were equally useful as samples of BAL for the diagnosis of invasive pulmonary aspergillosis. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
    Medical Mycology 01/2015; 53(3). DOI:10.1093/mmy/myu090 · 2.26 Impact Factor
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    ABSTRACT: Clinical breakpoints (CBPs) have not been established for the Mucorales and any antifungal agent. In lieu of CBPs, epidemiologic cutoff values (ECVs) are proposed for amphotericin B, posaconazole and itraconazole and four Mucorales species. Wild type (WT) MIC distributions (organisms in a species/drug combination with no detectable acquired resistance mechanisms) were defined with available pooled CLSI MICs from 14 laboratories (Argentina, Australia, Canada, Europe, India, Mexico, and the United States) as follows: 10 Apophysomyces variabilis, 32 Cunninghamella bertholletiae, 136 Lichtheimia corymbifera, 10 Mucor indicus, 123 M. circinelloides, 19 M. ramosissimus, 349 Rhizopus arrhizus, 146 R. microsporus, 33 Rhizomucor pusillus, and 36 Syncephalastrum racemosum. CLSI broth microdilution MICs were aggregated for the analyses. ECVs comprising ≥95% and ≥97.5% of the modeled populations were as follows: amphotericin B ECVs for L. corymbifera were 1 and 2 μg/ml, for M. circinelloides 1 and 2 μg/ml, for R. arrhizus 2 and 4 μg/ml, and for R. microsporus 2 and 2 μg/ml, respectively; posaconazole ECVs for L. corymbifera were 1 and 2, for M. circinelloides 4 and 4, for R. arrhizus 1 and 2, and for R. microsporus 1 and 2, respectively; both itraconazole ECVs for R. arrhizus were 2 μg/ml. ECVs may aid in detecting emerging resistance or those isolates with reduced susceptibility (non-WT-MICs) to the agents evaluated. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
    Antimicrobial Agents and Chemotherapy 01/2015; 59(3). DOI:10.1128/AAC.04435-14 · 4.45 Impact Factor
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    ABSTRACT: To longitudinally assess the shedding of antimicrobial resistant Clostridium difficile strains by clinically healthy dogs raised at breeding facilities. 18 puppies from three different litters (#1, 2 and 3) were sampled weekly from parturition to day 20-55 postpartum. Faecal samples from the mothers of litters #2 and 3 were also available for analysis. Bacterial isolates were ribotyped, tested for in vitro antimicrobial susceptibility and further characterised. C. difficile was recovered from all sampled animals of litters #1 and 2, and a third of puppies from litter #3, but marked differences in C. difficile recovery were detected in different age groups (0-100%). Recovered PCR ribotypes included 056 (22 isolates), 010 (6 isolates), 078 and 213 (2 isolates each), and 009 and 020 (1 isolate each). Different ribotypes were shed by four individual animals. Regardless of their origin and ribotype, all isolates demonstrated full resistance to levofloxacin. Additionally, all but one isolate (belonging to ribotype 078) were resistant to ertapenem, and all ribotype 010 isolates displayed high-level resistance to clindamycin, clarithromycin and erythromycin. A single ribotype 078 isolate showed metronidazole heteroresistance. Healthy dogs can shed antimicrobial-resistant C. difficile strains. © 2014 British Small Animal Veterinary Association.
    Journal of Small Animal Practice 12/2014; 56(3). DOI:10.1111/jsap.12311 · 0.91 Impact Factor
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    ABSTRACT: We studied whether STRAf can differentiate between A. fumigatus invasive and colonizing genotypes. Of the 395 genotypes detected (n=1,373 isolates), 50 were clusters, and 24 (6% of all genotypes) involved both patients with invasive aspergillosis and colonized patients, indicating that genotyping cannot discriminate between invasive and colonizing isolates. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
    Journal of Clinical Microbiology 11/2014; 53(2). DOI:10.1128/JCM.02636-14 · 4.23 Impact Factor
  • Enfermedades Infecciosas y Microbiología Clínica 10/2014; DOI:10.1016/j.eimc.2014.05.007 · 1.88 Impact Factor
  • Enfermedades Infecciosas y Microbiología Clínica 07/2014; · 1.88 Impact Factor
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    ABSTRACT: We assessed the in vitro activity of micafungin against preformed Candida biofilms by measuring the concentration of drug causing the most fungal damage and inhibition of regrowth. We studied 37 biofilm-producing Candida spp. strains from blood cultures. We showed that micafungin was active against planktonic and sessile forms of C. albicans strains and moderately active against C. parapsilosis sessile cells. Concentrations of micafungin above 2 μg/mL were sufficiently high to inactivate regrowth of Candida sessile cells.
    Antimicrobial Agents and Chemotherapy 06/2014; 58(9). DOI:10.1128/AAC.02738-14 · 4.45 Impact Factor
  • Medical Mycology 06/2014; 52(5):491-497. DOI:10.1093/mmy/myu013 · 2.26 Impact Factor
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    ABSTRACT: Catheter-related candidemia (CRC) is typically a biofilm related disease, but it is mostly unknown if the production of biofilm is a feature exclusively shown by Candida spp. isolates causing CRC. We performed an in vitro biofilm assay using Candida isolates obtained from the blood of patients with candidemia. We demonstrated that biofilm production was not a good predictor of catheter-related candidemia. Also, we demonstrated that there was no difference in the mortality of candidemia patients infected by biofilm-forming isolates and those in which the infection is caused by nonbiofilm-forming species.
    Medical mycology: official publication of the International Society for Human and Animal Mycology 04/2014; DOI:10.1093/mmy/myt031 · 2.26 Impact Factor
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    ABSTRACT: We determined the in vitro amphotericin B susceptibility of 60 Malassezia pachydermatis isolates by the CLSI broth microdilution method and the Etest using lipid-enriched media. All isolates were susceptible at a MIC ≤1 μg/ml, confirming the high activity of amphotericin B against this yeast species. Overall essential agreement between the tested methods was high (80% and 96.7% after 48 h and 72 h, respectively) and all discrepancies were regarded as non-substantial differences.
    Antimicrobial Agents and Chemotherapy 04/2014; 58(7). DOI:10.1128/AAC.00091-14 · 4.45 Impact Factor
  • Journal of Medical Microbiology 01/2014; 63. DOI:10.1099/jmm.0.068502-0 · 2.27 Impact Factor
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    ABSTRACT: Although ECVs (epidemiologic cutoff values) have been established for Candida spp. and the triazoles, they are based on MIC data from a single laboratory. We have established ECVs for eight Candida species and fluconazole, posaconazole and voriconazole based on wild-type (WT) MIC distributions for isolates of C. albicans (11, 241), C. glabrata (7, 538), C. parapsilosis (6, 023), C. tropicalis (3, 748), C. krusei (1, 073), C. lusitaniae (574), C. guilliermondii (373), and C. dubliniensis (162). The 24-h CLSI broth microdilution MICs were collated from multiple laboratories (Canada, Brazil, Europe, Mexico, Peru, and the United States). ECVs for distributions originating from ≥6 laboratories, which included ≥95% of the modelled WT population (fluconazole, posaconazole, and voriconazole, respectively) were: 0.5, 0.06 and 0.03 μg/ml for C. albicans; 0.5, 0.25, and 0.03 μg/ml for C. dubliniensis; 8, 1 and 0.25 μg/ml for C. glabrata; 8, 0.5 and 0.12 μg/ml for C. guilliermondii; 32, 0.5 and 0.25 μg/ml for C. krusei; 1, 0.06 and 0.06 μg/ml for C. lusitaniae; 1, 0.25 and 0.03 μg/ml for C. parapsilosis; and 1, 0.12 and 0.06 μg/ml for C. tropicalis. The low number of MICs (<100) for other less prevalent species (C. famata, C. kefyr, C. orthopsilosis, C. rugosa) precluded ECV definition, but their MIC distributions are documented. Evaluation of our ECVs for some species/agent combinations using published individual MICs for 136 isolates (harbouring mutations in or up-regulation of ERG11, MDR1, CDR1 and CDR2) and 64 WT isolates indicated that our ECVs may be useful in distinguishing WT from non-WT isolates.
    Antimicrobial Agents and Chemotherapy 01/2014; 58(4). DOI:10.1128/AAC.02615-13 · 4.45 Impact Factor
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    ABSTRACT: Clostridium difficile is an emerging and potentially zoonotic pathogen, but its prevalence in most animal species, including exhibition animals, is currently unknown. In this study we assessed the prevalence of faecal shedding of C. difficile by zoo animals, and determined the ribotype, toxin profile and antimicrobial susceptibility of recovered isolates. A total of 200 samples from 40 animal species (36.5% of which came from plains zebra, Equus quagga burchellii) were analysed. C. difficile was isolated from 7 samples (3.5% of total), which came from the following animal species: chimpanzee (Pan troglodytes troglodytes), dwarf goat (Capra hircus), and Iberian ibex (Capra pyrenaica hispanica), with one positive sample each; and plains zebra, with 4 positive samples from 3 different individuals. Most recovered isolates (4/7, 57.1%) belonged to the epidemic PCR ribotype 078, produced toxins A and B, and had the genes encoding binary toxin (i.e. A(+)B(+)CDT(+) isolates). The remaining three isolates belonged to PCR ribotypes 039 (A(-)B(-)CDT(-)), 042 (A(+)B(+)CDT(-)) and 110 (A(-)B(+)CDT(-)). Regardless of their ribotype, all isolates displayed high-level resistance to the fluoroquinolones ciprofloxacin, enrofloxacin and levofloxacin. Some isolates were also resistant to meropenem and/or ertapenem. A ribotype 078 isolate recovered from a male zebra foal initially showed in vitro resistance to metronidazole (MIC≥256μg/ml), but lost that trait after subculturing on non-selective media. We conclude that zoo animals belonging to different species can carry ribotype 078 and other toxigenic strains of C. difficile showing resistance to antimicrobial compounds commonly used in veterinary and/or human medicine.
    Veterinary Microbiology 01/2014; 169(3-4). DOI:10.1016/j.vetmic.2013.12.018 · 2.73 Impact Factor
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    ABSTRACT: Since epidemiological cutoff values (ECVs) using CLSI MICs from multiple laboratories are not available for Candida spp. and the echinocandins, we established ECVs for anidulafungin and micafungin based on wild-type (WT) MIC distributions (organisms in a species-drug combination with no detectable acquired resistance mechanisms) for 8,210 Candida albicans, 3,102 C. glabrata, 3,976 C. parapsilosis, 2,042 C. tropicalis, 617 C. krusei, 258 C. lusitaniae, 234 C. guilliermondii, and 131 C. dubliniensis isolates. CLSI broth microdilution MIC data gathered from 15 different laboratories in Canada, Europe, Mexico, Peru, and the United States were aggregated to statistically define ECVs. ECVs encompassing 97.5% of the statistically-modeled population (anidulafungin and micafungin, respectively) were 0.12 and 0.03 μg/mL for C. albicans, 0.12 and 0.03 μg/mL for C. glabrata, 8 and 4 μg/mL for C. parapsilosis, 0.12 and 0.06 μg/mL for C. tropicalis, 0.25 and 0.25 μg/mL for C. krusei, 1 and 0.5 μg/mL for C. lusitaniae, 8 and 2 μg/mL for C. guilliermondii, and 0.12 and 0.12 μg/mL for C. dubliniensis. Previously reported single and the multicenter ECVs defined in the present study were quite similar or within 1 two-fold dilution from each other. For a collection of 230 WT (no fks mutations) and 51 isolates with fks mutations, the species-specific ECVs for anidulafungin and micafungin correctly classified 47 (92.2%) and 51 (100%) of the fks mutants, respectively, as non-WT strains. These ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin and micafungin due to fks mutations.
    Antimicrobial Agents and Chemotherapy 11/2013; DOI:10.1128/AAC.02020-13 · 4.45 Impact Factor
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    ABSTRACT: Clostridium difficile ribotype 027 (Cd027) has caused outbreaks in the United States, Canada, and Europe since 2001. In Spain, the importance of Cd027 is still unknown. In 2007, we began active surveillance of Cd027 to determine its incidence in our hospital. From January 2007 to April 2012, isolates of C. difficile by multiplex PCR were studied to detect toxin genes. Binary toxin-positive isolates were characterized using PCR-ribotyping. Cd027 were further characterized by toxino-typing, sequencing of tcdC gene, and MLVA (multilocus-variable-number-tandem-repeat-analysis). Only 8 strains were Cd027 from 3666 isolates of C. difficile analyzed during the study period. These strains were isolated from 4 patients: a Spanish patient previously hospitalized in the UK, a pregnant laboratory technician, a British tourist, and a Spanish patient without epidemiological antecedents for acquiring Cd027. MLVA typing of Cd027 isolates revealed 4 different patterns. The first patient had 2 episodes of diarrhea caused by different Cd027. The strains from the first episode of patient 1 and the strain from patient 2 were grouped in the same clonal cluster (these cases were previously published as laboratory transmission), while strains from patients 3 and 4 were genetically unrelated to each other, and to the strains from patients 1 and 2. We report the first finding of an autochthonous case of non-severe Cd027 infection. Our results indicate that Cd027 diarrhea is uncommon in our area, and it appears mainly as imported cases. MLVA typing enables us to distinguish different genotypes among our Cd027 isolates.
    Enfermedades Infecciosas y Microbiología Clínica 09/2013; 32(6). DOI:10.1016/j.eimc.2013.07.004 · 1.88 Impact Factor
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    ABSTRACT: Although CLSI clinical breakpoints (CBPs) are available for interpreting echinocandin MICs for Candida spp., epidemiologic cutoff values (ECVs) based on collective MIC data from multiple laboratories have not been defined. While collating CLSI caspofungin MICs for 145 to 11,550 Candida isolates from 17 laboratories (Brazil, Canada, Europe, Mexico, Peru and the United States), we observed an extraordinary amount of modal variability (wide ranges) among laboratories as well as truncated and bimodal MIC distributions. The species-specific modes across different laboratories ranged from: 0.016-0.5 μg/ml for C. albicans and C. tropicalis; 0.031-0.5 μg/ml for C. glabrata; 0.063-1 μg/ml for C. krusei; variability was also similar among C. dubliniensis and C. lusitaniae. The exceptions were C. parapsilosis and C. guilliermondii MIC distributions, where most modes were within one twofold dilution of each other. These findings were consistent with available EUCAST data (403 to 2,556 MICs) for C. albicans, C. glabrata, C. krusei, and C. tropicalis. Although many factors (caspofungin powder source, stock solution solvent, powder storage time length and temperature, and MIC determination testing parameters) were examined as a potential cause of such unprecedented variability, a single specific cause was not identified. Therefore, it seems highly likely that the use of the CLSI species-specific caspofungin CBPs could lead to reporting an excessive number of wild-type [WT] (e.g., C. glabrata and C. krusei) as either non-WT or resistant isolates. Until this problem is resolved, routine testing or reporting of CLSI caspofungin MICs for Candida is not recommended; micafungin or anidulafungin data could be used instead.
    Antimicrobial Agents and Chemotherapy 09/2013; DOI:10.1128/AAC.01519-13 · 4.45 Impact Factor

Publication Stats

2k Citations
443.11 Total Impact Points


  • 2014–2015
    • Instituto de Investigación Sanitaria Gregorio Marañón
      Madrid, Madrid, Spain
  • 1997–2015
    • Complutense University of Madrid
      • Department of Medicine
      Madrid, Madrid, Spain
  • 1991–2015
    • Hospital General Universitario Gregorio Marañón
      • • Servicio de Aparato Digestivo
      • • Clinical Microbiology and Infectious Diseases
      • • Department of Clinical Microbiology
      Madrid, Madrid, Spain
  • 2011
    • Richmond VA Medical Center
      Richmond, Virginia, United States
    • University of Adelaide
      Tarndarnya, South Australia, Australia