Assuntos
Antibacterianos/farmacologia , Citrobacter/efeitos dos fármacos , Citrobacter/genética , Colistina/farmacologia , Microbiologia de Alimentos , Genes Bacterianos , Bolívia , Citrobacter/enzimologia , Citrobacter/isolamento & purificação , DNA Bacteriano/química , Farmacorresistência Bacteriana/genética , Plasmídeos , Análise de Sequência de DNA , Solanum tuberosum/microbiologiaAssuntos
Farmacorresistência Bacteriana Múltipla , Transferência Genética Horizontal , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Plasmídeos/análise , Adulto , Idoso , Antibacterianos/farmacologia , Bolívia , Eletroforese em Gel de Campo Pulsado , Feminino , Ordem dos Genes , Genótipo , Humanos , Klebsiella pneumoniae/classificação , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Análise de Sequência de DNARESUMO
BACKGROUND: Bolivia is among the lowest-resourced South American countries, with very few data available on antibiotic resistance in bacterial pathogens. The phenotypic and molecular characterization of bacterial isolates responsible for urinary tract infections (UTIs) in the Bolivian Chaco are reported here. METHODS: All clinical isolates from UTIs collected in the Hospital Basico Villa Montes between June 2010 and January 2014 were analyzed (N=213). Characterization included susceptibility testing, extended-spectrum beta-lactamase (ESBL) detection, identification of relevant resistance determinants (e.g., CTX-M-type ESBLs, 16S rRNA methyltransferases, glutathione S-transferases), and genotyping of CTX-M producers. RESULTS: Very high resistance rates were observed. Overall, the lowest susceptibility was observed for trimethoprim-sulphamethoxazole, tetracycline, nalidixic acid, amoxicillin-clavulanic acid, ciprofloxacin, and gentamicin. Of E. coli and K. pneumoniae, 11.6% were ESBL producers. Resistance to nitrofurantoin, amikacin, and fosfomycin remained low, and susceptibility to carbapenems was fully preserved. CTX-M-15 was the dominant CTX-M variant. Four E. coli ST131 (two being H30-Rx) were identified. Of note, isolates harbouring rmtB and fosA3 were detected. CONCLUSIONS: Bolivia is not an exception to the very high resistance burden affecting many South American countries. Optimization of alternative approaches to monitor local antibiotic resistance trends in resource-limited settings is strongly encouraged to support the implementation of effective empiric treatment guidelines.
Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Escherichia coli/isolamento & purificação , Klebsiella pneumoniae/isolamento & purificação , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Infecções Urinárias/microbiologia , Bolívia/epidemiologia , Farmacorresistência Bacteriana/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/genética , Fosfomicina/uso terapêutico , Genótipo , Humanos , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Metiltransferases/efeitos dos fármacos , Metiltransferases/genética , RNA Ribossômico 16S/efeitos dos fármacos , RNA Ribossômico 16S/genética , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/epidemiologia , beta-Lactamases/efeitos dos fármacos , beta-Lactamases/genéticaRESUMO
During the last decade, a significant diffusion of CTX-M-type extended-spectrum ß-lactamases (ESBLs) was observed in commensal Escherichia coli from healthy children in the Bolivian Chaco region, with initial dissemination of CTX-M-2, which was then replaced by CTX-M-15 and CTX-M-65. In this work, we demonstrate that the widespread dissemination of CTX-M-65 observed in this context was related to the polyclonal spreading of an IncI1 sequence type 71 (ST71) epidemic plasmid lineage. The structure of the epidemic plasmid population was characterized by complete sequencing of four representatives and PCR mapping of the remainder (n = 16). Sequence analysis showed identical plasmid backbones (similar to that of the reference IncI1 plasmid, R64) and a multiresistance region (MRR), which underwent local microevolution. The MRR harbored genes responsible for resistance to ß-lactams, aminoglycosides, florfenicol, and fosfomycin (with microevolution mainly consisting of deletion events of resistance modules). The bla CTX-M-65 module harbored by the IncI1 ST71 epidemic plasmid was apparently derived from IncN-type plasmids, likely via IS26-mediated mobilization. The plasmid could be transferred by conjugation to several different enterobacterial species (Escherichia coli, Cronobacter sakazakii, Enterobacter cloacae, Klebsiella oxytoca, Klebsiella pneumoniae, and Salmonella enterica) and was stably maintained without selective pressure in these species, with the exception of K. oxytoca and S. enterica. Fitness assays performed in E. coli recipients demonstrated that the presence of the epidemic plasmid was apparently not associated with a significant biological cost.
Assuntos
Plasmídeos/genética , beta-Lactamases/genética , beta-Lactamas/farmacologia , Antibacterianos/farmacologia , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/enzimologia , Enterobacter cloacae/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Fosfomicina/farmacologia , Klebsiella oxytoca/efeitos dos fármacos , Klebsiella oxytoca/enzimologia , Klebsiella oxytoca/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/enzimologia , Salmonella enterica/genética , beta-Lactamases/metabolismoRESUMO
OBJECTIVES: Information is lacking on the methicillin-resistant Staphylococcus aureus (MRSA) clonal lineages circulating in Bolivia. We investigated the prevalence and molecular epidemiology of S. aureus colonization in hospitalized patients from the Bolivian Chaco, and compared their features with those of the few clinical isolates available from that setting. METHODS: S. aureus nasal/inguinal colonization was investigated in 280 inpatients from eight hospitals in two point prevalence surveys (2012, n=90; 2013, n=190). Molecular characterization included genotyping (spa typing, multilocus sequence typing, and pulsed-field gel electrophoresis), detection of virulence genes, and SCCmec typing. RESULTS: Forty-one inpatients (14.6%) were S. aureus nasal/inguinal carriers, of whom five were colonized by MRSA (1.8%). MRSA isolates mostly belonged to spa-type t701, harboured SCCmec IVc, and were negative for Panton-Valentine leukocidin (PVL) genes. However, a USA300-related isolate was also detected, which showed the characteristics of the USA300 Latin American variant (USA300-LV; i.e., ST8, spa-type t008, SCCmec IVc, presence of PVL genes, absence of arcA). Notably, all the available MRSA clinical isolates (n=5, collected during 2011-2013) were also identified as USA300-LV. CONCLUSIONS: Overall, MRSA colonization in inpatients from the Bolivian Chaco was low. However, USA300-LV-related isolates were detected in colonization and infections, emphasizing the importance of implementing control measures to limit their further dissemination in this resource-limited area.
Assuntos
Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/microbiologia , Bolívia , Hospitalização , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/classificação , Prevalência , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/isolamento & purificaçãoRESUMO
OBJECTIVE: To investigate the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) nasal carriage in rural and urban community settings of Bolivia and Peru. METHODS: MRSA nasal carriage was investigated in 585 individuals living in rural and urban areas of Bolivia and Peru (one urban area, one small rural village, and two native communities, one of which was highly isolated). MRSA isolates were subjected to molecular analysis for the detection of virulence genes, characterization of the staphylococcal cassette chromosome mec (SCCmec), and genotyping (multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE)). RESULTS: An overall very low prevalence of MRSA nasal carriage was observed (0.5%), with MRSA carriers being detected only in a small rural village of the Bolivian Chaco. The three MRSA isolates showed the characteristics of community-associated MRSA (being susceptible to all non-beta-lactam antibiotics and harboring the SCCmec type IV), were clonally related, and belonged to ST1649. CONCLUSIONS: This study provides an insight into the epidemiology of MRSA in community settings of Bolivia and Peru. Reliable, time-saving, and low-cost methods should be implemented to encourage continued surveillance of MRSA dissemination in resource-limited countries.
Assuntos
Portador Sadio/epidemiologia , Staphylococcus aureus Resistente à Meticilina/genética , Nariz/microbiologia , Antibacterianos/farmacologia , Bolívia/epidemiologia , Criança , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Peru/epidemiologia , Prevalência , População Rural , População UrbanaRESUMO
BACKGROUND: Quinolones are potent broad-spectrum bactericidal agents increasingly employed also in resource-limited countries. Resistance to quinolones is an increasing problem, known to be strongly associated with quinolone exposure. We report on the emergence of quinolone resistance in a very remote community in the Amazon forest, where quinolones have never been used and quinolone resistance was absent in 2002. METHODS: The community exhibited a considerable level of geographical isolation, limited contact with the exterior and minimal antibiotic use (not including quinolones). In December 2009, fecal carriage of antibiotic resistant Escherichia coli was investigated in 120 of the 140 inhabitants, and in 48 animals reared in the community. All fluoroquinolone-resistant isolates were genotyped and characterized for the mechanisms of plasmid- and chromosomal-mediated quinolone resistance. PRINCIPAL FINDINGS: Despite the characteristics of the community remained substantially unchanged during the period 2002-2009, carriage of quinolone-resistant E. coli was found to be common in 2009 both in humans (45% nalidixic acid, 14% ciprofloxacin) and animals (54% nalidixic acid, 23% ciprofloxacin). Ciprofloxacin-resistant isolates of human and animal origin showed multidrug resistance phenotypes, a high level of genetic heterogeneity, and a combination of GyrA (Ser83Leu and Asp87Asn) and ParC (Ser80Ile) substitutions commonly observed in fluoroquinolone-resistant clinical isolates of E. coli. CONCLUSIONS: Remoteness and absence of antibiotic selective pressure did not protect the community from the remarkable emergence of quinolone resistance in E. coli. Introduction of the resistant strains from antibiotic-exposed settings is the most likely source, while persistence and dissemination in the absence of quinolone exposure is likely mostly related with poor sanitation. Interventions aimed at reducing the spreading of resistant isolates (by improving sanitation and water/food safety) are urgently needed to preserve the efficacy of quinolones in resource-limited countries, as control strategies based only on antibiotic restriction policies are unlikely to succeed in those settings.
Assuntos
Portador Sadio/microbiologia , Portador Sadio/veterinária , Farmacorresistência Bacteriana Múltipla , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Quinolonas/farmacologia , Adolescente , Adulto , Idoso , Animais , Antibacterianos/farmacologia , Criança , Pré-Escolar , Escherichia coli/classificação , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Feminino , Variação Genética , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Plasmídeos/análise , População Rural , América do Sul , Árvores , Adulto JovemAssuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Proteínas de Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Plasmídeos/genética , Quinolonas/farmacologia , Diarreia/epidemiologia , Diarreia/microbiologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Genótipo , Humanos , Lactente , Testes de Sensibilidade Microbiana , Peru/epidemiologia , Filogenia , Técnica de Amplificação ao Acaso de DNA PolimórficoRESUMO
We have previously observed high rates of acquired antibiotic resistance in commensal Escherichia coli from healthy children living in urban areas of Bolivia and Peru, including resistance to tetracycline and quinolones, which are not routinely used in childhood. In this work we investigated acquired resistance in commensal E. coli from healthy children and home-raised chickens in 12 households from one of the previously surveyed urban area in Bolivia, to ascertain the possibility of human-animal exchange of resistant strains in similar settings. The resistance rates to ampicillin, tetracycline, chloramphenicol, streptomycin, and trimethoprim-sulphametoxazole were overall high (≥50%) and comparable between children and chickens, whereas those to quinolones were significantly higher in chickens (81% vs. 29% for nalidixic acid; 43% vs. 10% for ciprofloxacin). Molecular characterization of tetracycline- and quinolone-resistant isolates (n = 66) from children and chickens of three selected households revealed a remarkable clonal diversity and, in some cases, the presence of the same resistant strains among children or among chickens living in the same household, but not between children and chickens. Several resistance plasmids were characterized, but inter-clonal plasmid dissemination was not detected. Overall, the results from the present study suggested that cross-transmission between children and home-raised chickens could not represent a major spreading mechanism for resistant E. coli in households of resource-limited settings with high human-animal promiscuity.
Assuntos
Antibacterianos/administração & dosagem , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/genética , Quinolonas/administração & dosagem , Tetraciclina/administração & dosagem , Animais , Bolívia/epidemiologia , Portador Sadio , Galinhas , Criança , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/transmissão , Fezes/microbiologia , Variação Genética , Humanos , Testes de Sensibilidade Microbiana , PlasmídeosAssuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana , Escherichia/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Plasmídeos/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Criança , Pré-Escolar , Escherichia/genética , Escherichia/isolamento & purificação , Proteínas de Escherichia coli/genética , Feminino , Humanos , Lactente , Recém-Nascido , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Peru , População Rural , Adulto JovemRESUMO
A remarkable prevalence of qnrB (54%) and, at a lower level, of qnrS (14%) was discovered in pools of commensal enterobacteria from 310 healthy children living in Peru and Bolivia, using a metagenomic approach. Analysis of randomly selected enterobacterial pools revealed that qnrB was mainly carried by Escherichia coli and qnrS by Klebsiella pneumoniae. Investigation of 11 qnrB-positive isolates and 9 qnrS-positive isolates revealed the presence of plasmid-borne qnrB19 (n = 8), qnrB2 (n = 2), qnrB10 (n = 1), and qnrS1 (n = 9) genes.