renata picao - Academia.edu (original) (raw)
Papers by renata picao
Environmental Pollution, Sep 1, 2020
The spread of carbapenemase-producing bacteria is a worldwide concern as it challenges healthcare... more The spread of carbapenemase-producing bacteria is a worldwide concern as it challenges healthcare, especially considering the insufficient development of antimicrobials. These microorganisms have been described not only in hospitals, but also in several environmental settings including recreational waters. Community exposure to antimicrobial-resistant bacteria through recreation might be relevant for human health, but risk assessment studies are lacking. Absence of effective and feasible monitoring in recreational aquatic matrices contributes to such a knowledge gap. Here, we aimed at assessing predictors of occurrence of medically relevant carbapenemase-producing bacteria in coastal waters. We quantitatively assessed recovery of carbapenemase-producing Enterobacteriaceae, Pseudomonas spp., Acinetobacter spp. and Aeromonas spp. in superficial coastal waters showing distinct pollution history across one year, and registered data regarding tide regimen, 7-days pluviosity, salinity, pH, water temperature. We analyzed data using General Estimating Equation (GEE) to assess predictors of such occurrence. Our results suggest that the sampling site had the strongest effect over concentration of these antimicrobial-resistant microorganisms, followed by pollution indexes and tide regimen. Increased salinity, advanced sampling time, water temperature, rainfall and decrease of pH were related to decrease concentrations. We provide a list of factors that could be easily monitored and further included in models aiming at predicting occurrence of carbapenemase producers in coastal waters. Our study may encourage researchers to further improve this list and validate the model proposed, so that monitoring and future public policies can be developed to control the spread of antimicrobial resistance in the environment.
International Journal of Antimicrobial Agents, 2017
Journal of Global Antimicrobial Resistance
Environmental Science & Technology
Environmental Microbiology
Journal of Global Antimicrobial Resistance
Abstract Objectives Flies have been implicated in the dispersal of medically important bacteria i... more Abstract Objectives Flies have been implicated in the dispersal of medically important bacteria including members of the genus Klebsiella between different environmental compartments. The aim of this study was to retrieve and characterize antibiotic-resistant bacteria from flies collected near to hospitals. Methods Flies were collected in the vicinity of medical facilities and examined for bacteria demonstrating phenotypic resistance to ceftriaxone, followed by determination of phenotypic and genotypic resistance profiles. In addition, whole genome sequencing followed by phylogenetic analysis and resistance genotyping were performed with the multidrug-resistant (MDR) strain Lemef23, identified as Klebsiella quasipneumoniae subsp. similipneumoniae. Results The strain Lemef23, classified by multiple locus sequence typing as novel ST 3397, harboured numerous resistance genes. The blaNDM was located on a Tn3000 element, a common genetic platform for the carriage of this gene in Brazil. Inference of phylogenetic orthology of strain Lemef23 and other clinical isolates suggested an anthropogenic origin. Conclusions The findings of this study support the role of flies as vectors of MDR bacteria of clinical importance and provide the first record of blaNDM-1 and blaCTXM-15 in a Brazilian isolate of K. quasipneumoniae subsp. similipneumoniae, demonstrating the value of surveying insects as reservoirs of antibiotic resistance.
New Microbes and New Infections
Polymyxins are important therapeutic options for treating infections, mainly those caused by carb... more Polymyxins are important therapeutic options for treating infections, mainly those caused by carbapenem-resistant Klebsiella pneumoniae. Specific chemical characteristics of polymyxins make it difficult to perform antimicrobial susceptibility testing, especially within the clinical laboratory. Here we aimed to evaluate the performance of three phenotypic methods: Rapid NP Polymyxin Test, ColiSpot test and the SuperPolymyxin medium. To accomplish this, 170 non-duplicate clinical K. pneumoniae isolates were analysed (123 colistin-resistant and 47 susceptible). The sensitivity and specificity obtained for Rapid Polymyxin NP Test, Colispot and SuperPolymyxin medium were, respectively, 90% and 94%, 74% and 100%, and 82% and 85%. Very major errors occurred more frequently in low-level colistin-resistant isolates (MICs 4 and 8 μg/mL). Rapid Polymyxin NP proved to be a method capable of identifying colistin-resistant strains in acceptable categorical agreement. However, major errors and very major errors of this method were considered unacceptable for colistinresistance screening. Although the Colispot test is promising and easy to perform and interpret, the results did not reproduce well in the isolates tested. The colistin-containing selective medium (SuperPolymyxin) showed limitations, including quantification of mucoid colonies and poor stability. Nevertheless, Colispot and SuperPolymyxin medium methods did not present acceptable sensitivity, specificity and categorical agreement. It is essential to use analytical tools that faithfully reproduce bacterial resistance in vitro, especially in last-line drugs, such as polymyxins, when misinterpretation of a test can result in therapeutic ineffectiveness.
Journal of Global Antimicrobial Resistance, 2022
OBJECTIVES Here we describe an IncQ1-like plasmid carrying blaKPC-2 in a new non-Tn4401 element f... more OBJECTIVES Here we describe an IncQ1-like plasmid carrying blaKPC-2 in a new non-Tn4401 element found in Citrobacter werkmanii recovered from coastal water. METHODS In vitro and in silico approaches were used to assess antimicrobial resistance determinants, as well as blaKPC-2 vicinities. RESULTS The LB-887 isolate showed a multidrug-resistant phenotype and was identified as Citrobacter werkmanii. Resistome analysis identified further acquired resistance determinants to β-lactams, aminoglycosides, sulfonamides/trimethoprim, tetracyclines, chloramphenicol, macrolides, rifampicin and fluoroquinolones. Plasmidome included incompatibility groups IncA, IncC2, IncR, Col and IncQ families. The blaKPC-2 was inserted on a new variant of NTEKPC-II, called here as NTEKPC-IIe, carried by an InQ1-like plasmid of 7,930 kb (pKPC-LB887). NTEKPC-IIe differed from NTEKPC-IId by the complete absence of ISKpn6-tnpA. The InQ1-like backbone harboring this element had been described in Enterobacterales recovered from clinical and environmental settings. CONCLUSIONS Unraveling genetic structures related to blaKPC dissemination in different settings may provide clues on the main forces driving evolution of this important resistance determinant. Indeed, the occurrence of blaKPC in a new NTEKPC variant from an environmental source highlights the ongoing evolution of this mobile genetic element. In addition, blaKPC carriage on a small and highly mobilizable IncQ plasmid in C. freundii complex from recreational water, similar to others found in clinical isolates, may suggest its relevance for blaKPC-2 dissemination among different compartments.
The Brazilian Journal of Infectious Diseases, 2022
Environmental Pollution, 2021
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Infection, Genetics and Evolution, 2021
Surgical site infections in instrumented posterior lumbar interbody fusion surgery are normally d... more Surgical site infections in instrumented posterior lumbar interbody fusion surgery are normally due to gram-positive bacteria, but gram-negative bacteria can cause infections in cases involving lower lumbar interventions as its closer to the perianal area. Here we report an uncommon fatal wound infection caused by a multidrug-resistant Klebsiella pneumoniae after an elective spine surgery. In silico analysis revealed that LWI_ST16 belonged to ST16, an emergent international clone notable for its increased virulence potential. We also observed that this strain carried a conjugative IncF plasmid encoding resistance genes to beta-lactams (blaKPC-2 and blaOXA-1), tetracycline (tetA), aminoglycosides and fluoroquinolones (aac(6')-Ib-cr). The carbapenemase encoding gene blaKPC-2 was located on a Tn4401e transposon previously characterized to increase blaKPC expression. LWI_ST16 is a strong biofilm producer on polystyrene and capable of forming tower-like structures on a titanium device like the one inserted in the patient's spine. Our findings strengthen the valuable contribution of continuous surveillance of multidrug-resistant and high-risk K. pneumoniae clones to avoid unfavourable clinical outcomes.
Memórias do Instituto Oswaldo Cruz, 2020
BACKGROUND Bacillus anthracis is the aetiologic agent of anthrax, a re-emerging, septicaemic, hae... more BACKGROUND Bacillus anthracis is the aetiologic agent of anthrax, a re-emerging, septicaemic, haemorrhagic and lethal disease that affects humans, domestic ruminants and wildlife. Plasmids pXO1 and pXO2 are attributes that confer pathogenicity to B. anthracis strains. This bacterium was used as biological weapon in the World Wars and in the biological attack in the United States of America at 2001. B. anthracis is classified as a Tier 1 bioterrorism agent by the Centers for Diseases Control and Prevention. Anthrax is recognised as a re-emerging disease. Several studies concerning the dynamics of B. anthracis cycle in soil revealed that nonpathogenic B. anthracis strains due to lack of pXO2 plasmid are commonly found in some types of soil. OBJECTIVES This study aimed isolation and identification of B. anthracis spores in soil samples of the state of Rio de Janeiro, Brazil. METHODS Phenotypic and genotypic approaches were used to identify isolates including MALDI-TOF/MS, motility test, susceptibility to gamma phage and penicillin, survey for pag and cap genes as surrogates of pXO1 and pXO2 plasmids, respectively, and sequencing of 16SrRNA-encoding gene. Physicochemical analysis of the soil samples were carried out to describe soil characteristics. FINDINGS We observed the presence of one B. anthracis pXO1+ and pXO2-isolated from clay loam soil; one B. anthracislike strain pXO1+ and pXO2-isolated from loamy sand; and 10 Bacillus spp. strains sensitive to phage-gamma that need better characterisation to define which their species were recovered from loamy sand. MAIN CONCLUSIONS This work showed promising results and it was the first study to report results from an active surveillance for B. anthracis in Brazil.
Brazilian Journal of Microbiology, 2019
Background Klebsiella infections are reported from neonatal intensive care units (NICUs) worldwid... more Background Klebsiella infections are reported from neonatal intensive care units (NICUs) worldwide, but data on their incidence and genetic diversity remain scarce. Objective We determined the incidence and genetic diversity of Klebsiella infections in NICU patients in Rio de Janeiro. Methods This was a prospective study including newborns admitted to NICU in three hospitals during April 2005-November 2006 and March 2008-February 2009. Klebsiella pneumoniae isolates were genotyped by multilocus sequence typing (MLST) and extended spectrum β-lactamases (ESBL) were characterized. Results Klebsiella infections occurred in 38 of 3984 patients (incidence rate, 9.5/1000 admissions); 14 (37%) of these 38 newborns died. Two clonal groups, CC45 and CC1041, caused 11 cases (42% of K. pneumoniae infection). Ten (32%) of the isolates causing infection produced ESBL, 9 of which (83%) carried bla CTX-M-15 , all belonging to clonal complex (CC) 45 and CC1041. Nine of these ESBL-producing isolates were confined to only one of the NICUs. Major conclusions The high incidence of Klebsiella infections in NICU in Rio de Janeiro appeared to be due to a combination of frequent sporadic infections caused by multiple K. pneumoniae genotypes and small outbreaks caused by dominant multidrugresistant clones.
Journal of global antimicrobial resistance, 2018
Background: The increasing use of antimicrobial agents for medical, veterinary and agricultural p... more Background: The increasing use of antimicrobial agents for medical, veterinary and agricultural practices contributes to the development and spread of resistance among environmental bacteria. The genus Aeromonas spp. is considered an important environmental reservoir for antibiotic resistance determinants. The aim of this study was to evaluate the prevalence of ESBLs among fifty Aeromonas spp. strains recovered from 2002 to 2005 from rivers, lakes and activated sludge in the Swiss Alps. Methods: The environmental isolates were submitted to ESBL phenotypic detection by double-disk synergy test followed by PCR using specific primers to ESBL genes. Results: One single isolate, A72, recovered in 2004 from an activated sludge, presented positive result for ESBL phenotypic detection. Amplification and DNA sequencing identified the presence of the blaPER-1 gene. This strain showed resistance to expanded-spectrum cephalosporins, and susceptibility to TZP, FOX, and IMP. It was also resistant...
Antimicrobial Agents and Chemotherapy, 2014
The Acinetobacter baumannii clonal complex 113/79 (CC113/79) and class 2 integrons predominate in... more The Acinetobacter baumannii clonal complex 113/79 (CC113/79) and class 2 integrons predominate in Latin America; a relationship between these characteristics was explored. The presence of integrases was determined in successive hospital Acinetobacter isolates (163 A. baumannii isolates and 72 Acinetobacter nosocomialis isolates). Most isolates had integrons, but class 1 and 2 integrons were present significantly more often in CC109/1 and CC113/79, respectively. The high prevalence of CC113/79 in Latin America may account for the predominance of class 2 integrons.
Microbial Drug Resistance, 2007
An Enterobacter cloacae strain showing decreased susceptibility to carbapenems was isolated from ... more An Enterobacter cloacae strain showing decreased susceptibility to carbapenems was isolated from a blood culture of a patient hospitalized in Genoa, Italy, and screened for the presence of metallo--lactamase (MBL) genes as part of the SENTRY Antimicrobial Surveillance Program. A bla VIM-1-carrying integron named In71 nearly identical to In70.2 reported in Pseudomonas aeruginosa strains isolated from various Italian cities since 2001 was identified in this strain. Interestingly, the In71 did not carry aadA1 nor possess the ISPa7 usually found in the P. aeruginosa integron In70.2. Mobilization of MBL genes from P. aeruginosa to members of the Enterobacteriaceae family is very worrisome because the rapid and wide dissemination of these potent antimicrobial resistance mechanisms could jeopardize the clinical use of carbapenems for the treatment of multidrug-resistant Enterobacteriaceae infections.
International Journal of Antimicrobial Agents, 2014
Activity of 4,5-dihydro-1H-pyrazoles against Mycobacterium tuberculosis and nontuberculous mycoba... more Activity of 4,5-dihydro-1H-pyrazoles against Mycobacterium tuberculosis and nontuberculous mycobacteria Sir, Tuberculosis (TB) is considered a neglected disease. The little investment in research towards the development of new drugs has recently changed as a result of the gravity and danger that TB represents, with high rates of morbidity and mortality as well as multidrug-resistant (MDR) TB [1]. In addition to Mycobacterium tuberculosis, there are other mycobacterial species that are opportunistic pathogens, and the number of cases of infections due to these nontuberculous mycobacteria (NTM) is increasing [2]. In this
FEMS Immunology & Medical Microbiology, 2003
The immune cross-reactivity between Trypanosoma cruzi, the protozoan that causes Chagas' disease,... more The immune cross-reactivity between Trypanosoma cruzi, the protozoan that causes Chagas' disease, and Phytomonas serpens, a trypanosomatid that infects tomatoes, was studied. Sera from patients with Chagas' disease presented a strong reactivity with P. serpens antigens by conventional serological assays such as indirect immunofluorescence (IIF) and direct agglutination test (DAT), confirmed after cross-absorption experiments. The results show that this protozoan is highly immunogenic and that rabbit and mouse hyperimmune serum raised against T. cruzi or P. serpens was able to recognize both T. cruzi and P. serpens antigens in immunofluorescence and agglutination assays. The antigenic cross-reactivity between T. cruzi and P. serpens was also demonstrated in vivo. BALB/c mice immunized by the intraperitoneal or oral route with P. serpens and later challenged with a lethal inoculum of T. cruzi blood forms showed a significant decrease in parasitemia and increase in survival compared to controls. A practical implication of these findings is that the ingestion by humans or animals of living plant trypanosomatids present in naturally infected edible fruits could potentially prime the immune response to T. cruzi antigens and interfere with the development of T. cruzi infection.
Expert Review of Anti-infective Therapy, 2010
The World Health Organization has rated multidrug-resistant (MDR) Gram-negative bacteria includin... more The World Health Organization has rated multidrug-resistant (MDR) Gram-negative bacteria including Pseudomonas aeruginosa (Psae) as serious threat to human health. We here addressed whether chronic murine gut inflammation facilitates intestinal MDR Psae colonization and whether bacterial infection subsequently worsens colonic immunopathology. Converse to wildtype counterparts, Psae colonized the intestines of IL-10 −/− mice with chronic colitis following peroral challenge, but did not lead to changes in intestinal microbiota composition. Psae infection accelerated both macroscopic (i.e. clinical) and microscopic disease (i.e. colonic epithelial apoptosis), that were accompanied by increased intestinal pro-inflammatory immune responses as indicated by elevated colonic numbers of innate and adaptive immune cell subsets and enhanced secretion of pro-inflammatory cytokines such as TNF and IFN-γ in mesenteric lymph nodes of Psae-infected as compared to unchallenged IL-10 −/− mice. Remarkably, Psae-induced pro-inflammatory immune responses were not restricted to the gut, but could also be observed systemically as indicated by increased TNF and IFN-γ concentrations in sera upon Psae-infection. Furthermore, viable commensals originating from the intestinal microbiota translocated to extra-intestinal compartments such as liver, kidney and spleen of Psae-infected IL-10 −/− mice with chronic colitis only. Hence, peroral MDR Psae-infection results in exacerbated colonic as well as systemic pro-inflammatory immune responses during chronic murine colitis. Pseudomonas aeruginosa (Psae), constitute opportunistic pathogens, that may cause a variety of nosocomial infections particularly in immunocompromised patients or patients with chronic pulmonary diseases such as chronic obstructive pulmonary disease or cystic fibrosis 1-4. Patients suffering from ventilator-associated pneumonia or burn wound infections face high mortality rates of over 30% 1. As Gram-negative bacteria with emerging antimicrobial resistance Psae are among several multi-drug resistant (MDR) bacterial species that can be found in a global priority pathogen list issued by the World Health Organization (WHO) in order to help prioritizing the development of novel antimicrobial strategies 5. Already early studies suggest that besides contaminated respirators and other medical equipment the human gastrointestinal tract might be an important internal source of Psae infection in hospitals 6,7. Furthermore, a recent study revealed that a majority of intensive care unit (ICU) patients with a Psae infection displayed prior rectal colonization with the bacterial opportunistic pathogen 8. Particularly a preceding antimicrobial treatment had been shown to disturb the complex intestinal microbiota composition and therefore to compromise the physiological colonization resistance 9-12 which, in turn, may enable invading (opportunistic) pathogens including MDR Psae to establish within the human gastrointestinal ecosystem 13. However, valid scientific data concerning the pathogenic potential of Psae infection of the intestinal tract are scarce. Our very recent study revealed for the first time that mere intestinal carriage of a clinical MDR Psae isolate by otherwise healthy microbiota-depleted wildtype (WT) mice resulted in distinct local as well as systemic pro-inflammatory immune responses 13. We were further able to demonstrate that with intestinal inflammation
Environmental Pollution, Sep 1, 2020
The spread of carbapenemase-producing bacteria is a worldwide concern as it challenges healthcare... more The spread of carbapenemase-producing bacteria is a worldwide concern as it challenges healthcare, especially considering the insufficient development of antimicrobials. These microorganisms have been described not only in hospitals, but also in several environmental settings including recreational waters. Community exposure to antimicrobial-resistant bacteria through recreation might be relevant for human health, but risk assessment studies are lacking. Absence of effective and feasible monitoring in recreational aquatic matrices contributes to such a knowledge gap. Here, we aimed at assessing predictors of occurrence of medically relevant carbapenemase-producing bacteria in coastal waters. We quantitatively assessed recovery of carbapenemase-producing Enterobacteriaceae, Pseudomonas spp., Acinetobacter spp. and Aeromonas spp. in superficial coastal waters showing distinct pollution history across one year, and registered data regarding tide regimen, 7-days pluviosity, salinity, pH, water temperature. We analyzed data using General Estimating Equation (GEE) to assess predictors of such occurrence. Our results suggest that the sampling site had the strongest effect over concentration of these antimicrobial-resistant microorganisms, followed by pollution indexes and tide regimen. Increased salinity, advanced sampling time, water temperature, rainfall and decrease of pH were related to decrease concentrations. We provide a list of factors that could be easily monitored and further included in models aiming at predicting occurrence of carbapenemase producers in coastal waters. Our study may encourage researchers to further improve this list and validate the model proposed, so that monitoring and future public policies can be developed to control the spread of antimicrobial resistance in the environment.
International Journal of Antimicrobial Agents, 2017
Journal of Global Antimicrobial Resistance
Environmental Science & Technology
Environmental Microbiology
Journal of Global Antimicrobial Resistance
Abstract Objectives Flies have been implicated in the dispersal of medically important bacteria i... more Abstract Objectives Flies have been implicated in the dispersal of medically important bacteria including members of the genus Klebsiella between different environmental compartments. The aim of this study was to retrieve and characterize antibiotic-resistant bacteria from flies collected near to hospitals. Methods Flies were collected in the vicinity of medical facilities and examined for bacteria demonstrating phenotypic resistance to ceftriaxone, followed by determination of phenotypic and genotypic resistance profiles. In addition, whole genome sequencing followed by phylogenetic analysis and resistance genotyping were performed with the multidrug-resistant (MDR) strain Lemef23, identified as Klebsiella quasipneumoniae subsp. similipneumoniae. Results The strain Lemef23, classified by multiple locus sequence typing as novel ST 3397, harboured numerous resistance genes. The blaNDM was located on a Tn3000 element, a common genetic platform for the carriage of this gene in Brazil. Inference of phylogenetic orthology of strain Lemef23 and other clinical isolates suggested an anthropogenic origin. Conclusions The findings of this study support the role of flies as vectors of MDR bacteria of clinical importance and provide the first record of blaNDM-1 and blaCTXM-15 in a Brazilian isolate of K. quasipneumoniae subsp. similipneumoniae, demonstrating the value of surveying insects as reservoirs of antibiotic resistance.
New Microbes and New Infections
Polymyxins are important therapeutic options for treating infections, mainly those caused by carb... more Polymyxins are important therapeutic options for treating infections, mainly those caused by carbapenem-resistant Klebsiella pneumoniae. Specific chemical characteristics of polymyxins make it difficult to perform antimicrobial susceptibility testing, especially within the clinical laboratory. Here we aimed to evaluate the performance of three phenotypic methods: Rapid NP Polymyxin Test, ColiSpot test and the SuperPolymyxin medium. To accomplish this, 170 non-duplicate clinical K. pneumoniae isolates were analysed (123 colistin-resistant and 47 susceptible). The sensitivity and specificity obtained for Rapid Polymyxin NP Test, Colispot and SuperPolymyxin medium were, respectively, 90% and 94%, 74% and 100%, and 82% and 85%. Very major errors occurred more frequently in low-level colistin-resistant isolates (MICs 4 and 8 μg/mL). Rapid Polymyxin NP proved to be a method capable of identifying colistin-resistant strains in acceptable categorical agreement. However, major errors and very major errors of this method were considered unacceptable for colistinresistance screening. Although the Colispot test is promising and easy to perform and interpret, the results did not reproduce well in the isolates tested. The colistin-containing selective medium (SuperPolymyxin) showed limitations, including quantification of mucoid colonies and poor stability. Nevertheless, Colispot and SuperPolymyxin medium methods did not present acceptable sensitivity, specificity and categorical agreement. It is essential to use analytical tools that faithfully reproduce bacterial resistance in vitro, especially in last-line drugs, such as polymyxins, when misinterpretation of a test can result in therapeutic ineffectiveness.
Journal of Global Antimicrobial Resistance, 2022
OBJECTIVES Here we describe an IncQ1-like plasmid carrying blaKPC-2 in a new non-Tn4401 element f... more OBJECTIVES Here we describe an IncQ1-like plasmid carrying blaKPC-2 in a new non-Tn4401 element found in Citrobacter werkmanii recovered from coastal water. METHODS In vitro and in silico approaches were used to assess antimicrobial resistance determinants, as well as blaKPC-2 vicinities. RESULTS The LB-887 isolate showed a multidrug-resistant phenotype and was identified as Citrobacter werkmanii. Resistome analysis identified further acquired resistance determinants to β-lactams, aminoglycosides, sulfonamides/trimethoprim, tetracyclines, chloramphenicol, macrolides, rifampicin and fluoroquinolones. Plasmidome included incompatibility groups IncA, IncC2, IncR, Col and IncQ families. The blaKPC-2 was inserted on a new variant of NTEKPC-II, called here as NTEKPC-IIe, carried by an InQ1-like plasmid of 7,930 kb (pKPC-LB887). NTEKPC-IIe differed from NTEKPC-IId by the complete absence of ISKpn6-tnpA. The InQ1-like backbone harboring this element had been described in Enterobacterales recovered from clinical and environmental settings. CONCLUSIONS Unraveling genetic structures related to blaKPC dissemination in different settings may provide clues on the main forces driving evolution of this important resistance determinant. Indeed, the occurrence of blaKPC in a new NTEKPC variant from an environmental source highlights the ongoing evolution of this mobile genetic element. In addition, blaKPC carriage on a small and highly mobilizable IncQ plasmid in C. freundii complex from recreational water, similar to others found in clinical isolates, may suggest its relevance for blaKPC-2 dissemination among different compartments.
The Brazilian Journal of Infectious Diseases, 2022
Environmental Pollution, 2021
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Infection, Genetics and Evolution, 2021
Surgical site infections in instrumented posterior lumbar interbody fusion surgery are normally d... more Surgical site infections in instrumented posterior lumbar interbody fusion surgery are normally due to gram-positive bacteria, but gram-negative bacteria can cause infections in cases involving lower lumbar interventions as its closer to the perianal area. Here we report an uncommon fatal wound infection caused by a multidrug-resistant Klebsiella pneumoniae after an elective spine surgery. In silico analysis revealed that LWI_ST16 belonged to ST16, an emergent international clone notable for its increased virulence potential. We also observed that this strain carried a conjugative IncF plasmid encoding resistance genes to beta-lactams (blaKPC-2 and blaOXA-1), tetracycline (tetA), aminoglycosides and fluoroquinolones (aac(6')-Ib-cr). The carbapenemase encoding gene blaKPC-2 was located on a Tn4401e transposon previously characterized to increase blaKPC expression. LWI_ST16 is a strong biofilm producer on polystyrene and capable of forming tower-like structures on a titanium device like the one inserted in the patient's spine. Our findings strengthen the valuable contribution of continuous surveillance of multidrug-resistant and high-risk K. pneumoniae clones to avoid unfavourable clinical outcomes.
Memórias do Instituto Oswaldo Cruz, 2020
BACKGROUND Bacillus anthracis is the aetiologic agent of anthrax, a re-emerging, septicaemic, hae... more BACKGROUND Bacillus anthracis is the aetiologic agent of anthrax, a re-emerging, septicaemic, haemorrhagic and lethal disease that affects humans, domestic ruminants and wildlife. Plasmids pXO1 and pXO2 are attributes that confer pathogenicity to B. anthracis strains. This bacterium was used as biological weapon in the World Wars and in the biological attack in the United States of America at 2001. B. anthracis is classified as a Tier 1 bioterrorism agent by the Centers for Diseases Control and Prevention. Anthrax is recognised as a re-emerging disease. Several studies concerning the dynamics of B. anthracis cycle in soil revealed that nonpathogenic B. anthracis strains due to lack of pXO2 plasmid are commonly found in some types of soil. OBJECTIVES This study aimed isolation and identification of B. anthracis spores in soil samples of the state of Rio de Janeiro, Brazil. METHODS Phenotypic and genotypic approaches were used to identify isolates including MALDI-TOF/MS, motility test, susceptibility to gamma phage and penicillin, survey for pag and cap genes as surrogates of pXO1 and pXO2 plasmids, respectively, and sequencing of 16SrRNA-encoding gene. Physicochemical analysis of the soil samples were carried out to describe soil characteristics. FINDINGS We observed the presence of one B. anthracis pXO1+ and pXO2-isolated from clay loam soil; one B. anthracislike strain pXO1+ and pXO2-isolated from loamy sand; and 10 Bacillus spp. strains sensitive to phage-gamma that need better characterisation to define which their species were recovered from loamy sand. MAIN CONCLUSIONS This work showed promising results and it was the first study to report results from an active surveillance for B. anthracis in Brazil.
Brazilian Journal of Microbiology, 2019
Background Klebsiella infections are reported from neonatal intensive care units (NICUs) worldwid... more Background Klebsiella infections are reported from neonatal intensive care units (NICUs) worldwide, but data on their incidence and genetic diversity remain scarce. Objective We determined the incidence and genetic diversity of Klebsiella infections in NICU patients in Rio de Janeiro. Methods This was a prospective study including newborns admitted to NICU in three hospitals during April 2005-November 2006 and March 2008-February 2009. Klebsiella pneumoniae isolates were genotyped by multilocus sequence typing (MLST) and extended spectrum β-lactamases (ESBL) were characterized. Results Klebsiella infections occurred in 38 of 3984 patients (incidence rate, 9.5/1000 admissions); 14 (37%) of these 38 newborns died. Two clonal groups, CC45 and CC1041, caused 11 cases (42% of K. pneumoniae infection). Ten (32%) of the isolates causing infection produced ESBL, 9 of which (83%) carried bla CTX-M-15 , all belonging to clonal complex (CC) 45 and CC1041. Nine of these ESBL-producing isolates were confined to only one of the NICUs. Major conclusions The high incidence of Klebsiella infections in NICU in Rio de Janeiro appeared to be due to a combination of frequent sporadic infections caused by multiple K. pneumoniae genotypes and small outbreaks caused by dominant multidrugresistant clones.
Journal of global antimicrobial resistance, 2018
Background: The increasing use of antimicrobial agents for medical, veterinary and agricultural p... more Background: The increasing use of antimicrobial agents for medical, veterinary and agricultural practices contributes to the development and spread of resistance among environmental bacteria. The genus Aeromonas spp. is considered an important environmental reservoir for antibiotic resistance determinants. The aim of this study was to evaluate the prevalence of ESBLs among fifty Aeromonas spp. strains recovered from 2002 to 2005 from rivers, lakes and activated sludge in the Swiss Alps. Methods: The environmental isolates were submitted to ESBL phenotypic detection by double-disk synergy test followed by PCR using specific primers to ESBL genes. Results: One single isolate, A72, recovered in 2004 from an activated sludge, presented positive result for ESBL phenotypic detection. Amplification and DNA sequencing identified the presence of the blaPER-1 gene. This strain showed resistance to expanded-spectrum cephalosporins, and susceptibility to TZP, FOX, and IMP. It was also resistant...
Antimicrobial Agents and Chemotherapy, 2014
The Acinetobacter baumannii clonal complex 113/79 (CC113/79) and class 2 integrons predominate in... more The Acinetobacter baumannii clonal complex 113/79 (CC113/79) and class 2 integrons predominate in Latin America; a relationship between these characteristics was explored. The presence of integrases was determined in successive hospital Acinetobacter isolates (163 A. baumannii isolates and 72 Acinetobacter nosocomialis isolates). Most isolates had integrons, but class 1 and 2 integrons were present significantly more often in CC109/1 and CC113/79, respectively. The high prevalence of CC113/79 in Latin America may account for the predominance of class 2 integrons.
Microbial Drug Resistance, 2007
An Enterobacter cloacae strain showing decreased susceptibility to carbapenems was isolated from ... more An Enterobacter cloacae strain showing decreased susceptibility to carbapenems was isolated from a blood culture of a patient hospitalized in Genoa, Italy, and screened for the presence of metallo--lactamase (MBL) genes as part of the SENTRY Antimicrobial Surveillance Program. A bla VIM-1-carrying integron named In71 nearly identical to In70.2 reported in Pseudomonas aeruginosa strains isolated from various Italian cities since 2001 was identified in this strain. Interestingly, the In71 did not carry aadA1 nor possess the ISPa7 usually found in the P. aeruginosa integron In70.2. Mobilization of MBL genes from P. aeruginosa to members of the Enterobacteriaceae family is very worrisome because the rapid and wide dissemination of these potent antimicrobial resistance mechanisms could jeopardize the clinical use of carbapenems for the treatment of multidrug-resistant Enterobacteriaceae infections.
International Journal of Antimicrobial Agents, 2014
Activity of 4,5-dihydro-1H-pyrazoles against Mycobacterium tuberculosis and nontuberculous mycoba... more Activity of 4,5-dihydro-1H-pyrazoles against Mycobacterium tuberculosis and nontuberculous mycobacteria Sir, Tuberculosis (TB) is considered a neglected disease. The little investment in research towards the development of new drugs has recently changed as a result of the gravity and danger that TB represents, with high rates of morbidity and mortality as well as multidrug-resistant (MDR) TB [1]. In addition to Mycobacterium tuberculosis, there are other mycobacterial species that are opportunistic pathogens, and the number of cases of infections due to these nontuberculous mycobacteria (NTM) is increasing [2]. In this
FEMS Immunology & Medical Microbiology, 2003
The immune cross-reactivity between Trypanosoma cruzi, the protozoan that causes Chagas' disease,... more The immune cross-reactivity between Trypanosoma cruzi, the protozoan that causes Chagas' disease, and Phytomonas serpens, a trypanosomatid that infects tomatoes, was studied. Sera from patients with Chagas' disease presented a strong reactivity with P. serpens antigens by conventional serological assays such as indirect immunofluorescence (IIF) and direct agglutination test (DAT), confirmed after cross-absorption experiments. The results show that this protozoan is highly immunogenic and that rabbit and mouse hyperimmune serum raised against T. cruzi or P. serpens was able to recognize both T. cruzi and P. serpens antigens in immunofluorescence and agglutination assays. The antigenic cross-reactivity between T. cruzi and P. serpens was also demonstrated in vivo. BALB/c mice immunized by the intraperitoneal or oral route with P. serpens and later challenged with a lethal inoculum of T. cruzi blood forms showed a significant decrease in parasitemia and increase in survival compared to controls. A practical implication of these findings is that the ingestion by humans or animals of living plant trypanosomatids present in naturally infected edible fruits could potentially prime the immune response to T. cruzi antigens and interfere with the development of T. cruzi infection.
Expert Review of Anti-infective Therapy, 2010
The World Health Organization has rated multidrug-resistant (MDR) Gram-negative bacteria includin... more The World Health Organization has rated multidrug-resistant (MDR) Gram-negative bacteria including Pseudomonas aeruginosa (Psae) as serious threat to human health. We here addressed whether chronic murine gut inflammation facilitates intestinal MDR Psae colonization and whether bacterial infection subsequently worsens colonic immunopathology. Converse to wildtype counterparts, Psae colonized the intestines of IL-10 −/− mice with chronic colitis following peroral challenge, but did not lead to changes in intestinal microbiota composition. Psae infection accelerated both macroscopic (i.e. clinical) and microscopic disease (i.e. colonic epithelial apoptosis), that were accompanied by increased intestinal pro-inflammatory immune responses as indicated by elevated colonic numbers of innate and adaptive immune cell subsets and enhanced secretion of pro-inflammatory cytokines such as TNF and IFN-γ in mesenteric lymph nodes of Psae-infected as compared to unchallenged IL-10 −/− mice. Remarkably, Psae-induced pro-inflammatory immune responses were not restricted to the gut, but could also be observed systemically as indicated by increased TNF and IFN-γ concentrations in sera upon Psae-infection. Furthermore, viable commensals originating from the intestinal microbiota translocated to extra-intestinal compartments such as liver, kidney and spleen of Psae-infected IL-10 −/− mice with chronic colitis only. Hence, peroral MDR Psae-infection results in exacerbated colonic as well as systemic pro-inflammatory immune responses during chronic murine colitis. Pseudomonas aeruginosa (Psae), constitute opportunistic pathogens, that may cause a variety of nosocomial infections particularly in immunocompromised patients or patients with chronic pulmonary diseases such as chronic obstructive pulmonary disease or cystic fibrosis 1-4. Patients suffering from ventilator-associated pneumonia or burn wound infections face high mortality rates of over 30% 1. As Gram-negative bacteria with emerging antimicrobial resistance Psae are among several multi-drug resistant (MDR) bacterial species that can be found in a global priority pathogen list issued by the World Health Organization (WHO) in order to help prioritizing the development of novel antimicrobial strategies 5. Already early studies suggest that besides contaminated respirators and other medical equipment the human gastrointestinal tract might be an important internal source of Psae infection in hospitals 6,7. Furthermore, a recent study revealed that a majority of intensive care unit (ICU) patients with a Psae infection displayed prior rectal colonization with the bacterial opportunistic pathogen 8. Particularly a preceding antimicrobial treatment had been shown to disturb the complex intestinal microbiota composition and therefore to compromise the physiological colonization resistance 9-12 which, in turn, may enable invading (opportunistic) pathogens including MDR Psae to establish within the human gastrointestinal ecosystem 13. However, valid scientific data concerning the pathogenic potential of Psae infection of the intestinal tract are scarce. Our very recent study revealed for the first time that mere intestinal carriage of a clinical MDR Psae isolate by otherwise healthy microbiota-depleted wildtype (WT) mice resulted in distinct local as well as systemic pro-inflammatory immune responses 13. We were further able to demonstrate that with intestinal inflammation