High plasmid variability, and the presence of IncFIB, IncQ, IncA/C, IncHI1B, and IncL/M in clinical isolates of Klebsiella pneumoniae with bla KPC and bla NDM from patients at a public hospital in Brazil

Abstract INTRODUCTION Antibiotic resistance in carbapenemase-producing Klebsiella pneumoniae is acquired and disseminated mainly by plasmids. Therefore, we aimed to investigate the occurrence of carbapenemase genes, analyze the genetic diversity by ERIC-PCR, and examine the most common plasmid incompatibility groups (Incs) in clinical isolates of K. pneumoniae from colonization and infection in patients from a hospital in Brazil. METHODS Twenty-seven isolates of carbapenem-resistant K. pneumoniae were selected and screened for the presence of carbapenemase genes and Incs by PCR, followed by amplicon sequencing. RESULTS The bla KPC and bla NDM genes were detected in 24 (88.8 %) and 16 (59.2 %) of the isolates, respectively. Thirteen isolates (48.1 %) were positive for both genes. The IncFIB (92.6 %) and IncQ (88.8 %) were the most frequent plasmids, followed by IncA/C, IncHI1B, and IncL/M, indicating that plasmid variability existed in these isolates. To our knowledge, this is the first report of IncHI1B in Brazil. We found eight isolates with clonal relationship distributed in different sectors of the hospital. CONCLUSIONS The accumulation of resistance determinants, the variability of plasmid Incs, and the clonal dissemination detected in K. pneumoniae isolates demonstrate their potential for infection, colonization, and the dissemination of different resistance genes and plasmids.

Emergence of aph(3')-VI and accumulation of aminoglycoside modifying enzyme genes in KPC-2-possessing Enterobacter aerogenes isolates from infections and colonization in patients from Recife-PE, Brazil

Abstract INTRODUCTION: The objective of this study was to characterize genes of aminoglycoside modifying enzymes (AMEs) in colonizing and infecting isolates of E. aerogenes harboring bla KPC from patients at a public hospital in Recife-PE, Brazil. METHODS: We analyzed 29 E. aerogenes clinical isolates resistant to aminoglycosides. AMEs genes were investigated by PCR and sequencing. RESULTS: Colonizing and infecting isolates mainly presented the genetic profiles aac(3)-IIa/aph(3')-VI or ant(2")-IIa/aph(3')-VI. This is the first report of aph(3')-VI in E. aerogenes harboring bla KPC in Brazil. CONCLUSIONS: The results highlight the importance in establishing rigorous methods for the surveillance of resistance genes, especially in colonized patients.

Investigation of class 1 integrons in Klebsiella pneumoniae clinical and microbiota isolates belonging to different phylogenetic groups in Recife, State of Pernambuco

Introduction The high prevalence of Klebsiella pneumoniae infections is related to the ability of K. pneumoniae to acquire and disseminate exogenous genes associated with mobile elements, such as R plasmids, transposons and integrons. This study investigated the presence of class 1 integrons in clinical and microbiota isolates of K. pneumoniae belonging to different phylogenetic groups and correlated these results with the antimicrobial resistance profiles of the studied isolates. Methods Of the 51 isolates of K. pneumoniae selected for this study, 29 were from multidrug-resistant clinical isolates, and 22 were from children's microbiota. The susceptibility profile was determined using the disk diffusion method, and class 1 integrons were detected through polymerase chain reaction (PCR). Results The results showed that none of the 22 microbiota isolates carried class 1 integrons. Among the 29 clinical isolates, 19 (65.5%) contained class 1 integrons, and resistance to sulfamethoxazole/trimethoprim was identified in 18 of these isolates (94.7%). Among the K. pneumoniae isolates with class 1 integrons, 47% belonged to the KpI phylogenetic group, and one isolate (14.3%) carrying these genetic elements belonged to the KpIII group. Conclusions The wide variety of detected class 1 integrons supports the presence of high rates of antimicrobial resistance, genetic variability, and rapid dissemination of beta-lactamase genes among K. pneumoniae clinical isolates in recent years in hospitals in Recife-PE, Brazil. The findings of this study indicate that the surveillance of K. pneumoniae integrons in clinical isolates could be useful for monitoring the spread of antibiotic resistance genes in the hospital environment. .

Phenotypic and molecular characterization of antimicrobial resistance and virulence factors in Pseudomonas aeruginosa clinical isolates from Recife, State of Pernambuco, Brazil / Caracterização fenotípica e molecular de fatores de resistência a antimicrobianos e virulência de isolados clínicos de Pseudomonas aeruginosa de Recife, Estado de Pernambuco, Brasil

INTRODUCTION: The emergence of carbapenem resistance mechanisms in Pseudomonas aeruginosa has been outstanding due to the wide spectrum of antimicrobial degradation of these bacteria, reducing of therapeutic options. METHODS: Sixty-one clinical strains of P. aeruginosa isolated from five public hospitals in Recife, Pernambuco, Brazil, were examined between 2006 and 2010, aiming of evaluating the profiles of virulence, resistance to antimicrobials, presence of metallo-β-lactamase (MBL) genes, and clonal relationship among isolates. RESULTS: A high percentage of virulence factors (34.4% mucoid colonies; 70.5% pyocyanin; 93.4% gelatinase positives; and 72.1% hemolysin positive) and a high percentage of antimicrobial resistance rates (4.9% pan-resistant and 54.1% multi-drug resistant isolates) were observed. Among the 29 isolates resistant to imipenem and/or ceftazidime, 44.8% (13/29) were MBL producers by phenotypic evaluation, and of these, 46.2% (6/13) were positive for the blaSPM-1 gene. The blaIMP and blaVIM genes were not detected. The molecular typing revealed 21 molecular profiles of which seven were detected in distinct hospitals and periods. Among the six positive blaSPM-1 isolates, three presented the same clonal profile and were from the same hospital, whereas the other three presented different clonal profiles. CONCLUSIONS: These results revealed that P. aeruginosa is able to accumulate different resistance and virulence factors, making the treatment of infections difficult. The identification of blaSPM-1 genes and the dissemination of clones in different hospitals, indicate the need for stricter application of infection control measures in hospitals in Recife, Brazil, aiming at reducing costs and damages caused by P. aeruginosa infections.

INTRODUÇÃO: A emergência de mecanismos de resistência aos carbapenêmicos em Pseudomonas aeruginosa tem se destacado devido ao amplo espectro de degradação de antimicrobianos, reduzindo as opções terapêuticas. MÉTODOS: Sessenta e um isolados de P. aeruginosa procedentes de cinco hospitais públicos de Recife, Pernambuco, Brasil, entre 2006 e 2010, foram analisadas, com o objetivo de avaliar o perfil de virulência, resistência aos antimicrobianos, a presença de genes metalo-β-lactamase (MBL) e a relação clonal entre os isolados. RESULTADOS: Foi observada uma elevada produção de fatores de virulência na amostra (34,4% colônias mucoides; 70,5% piocianina; 93,4% gelatinase e 72,1% hemolisina), bem como um elevado percentual de resistência (4,9% isolados panresistentes e 54,1% multirresistentes). Dentre os 29 isolados resistentes ao imipenem e/ou ceftazidima, 44,8% (13/29) apresentaram MBL por meio da pesquisa fenotípica, e destes, 46,2% (6/13) foram positivos para o gene blaSPM-1, não havendo detecção dos genes blaIMP e blaVIM. A tipagem molecular revelou 21 perfis genéticos dos quais sete foram detectados em hospitais e períodos distintos, e dos isolados blaSPM-1 positivos, três apresentaram o mesmo perfil clonal e foram procedentes do mesmo hospital, enquanto que os outros três isolados blaSPM-1 positivos apresentaram perfis clonais distintos. CONCLUSÕES: Estes resultados revelam que a P. aeruginosa é capaz de acumular diferentes fatores de virulência e resistência, dificultando o tratamento das infecções. A identificação de genes blaSPM-1 e disseminação de clones sugere a necessidade de aplicação mais rigorosa de medidas de controle de infecção nos hospitais de Recife, visando reduzir custos e danos provocados por este tipo de infecção.

Multidrug resistance genes, including blaKPC and blaCTX-M-2, among Klebsiella pneumoniae isolated in Recife, Brazil / Genes de multirresistência, incluindo blaKPC e blaCTX-M-2, em Klebsiella pneumoniae isoladas em Recife, Brasil

INTRODUCTION: The prevalence of cephalosporins and carbapenem-resistant Klebsiella pneumoniae strains is rising in Brazil, with potential serious consequences in terms of patients' outcomes and general care. METHODS: This study characterized 24 clinical isolates of K. pneumoniae from two hospitals in Recife, Brazil, through the antimicrobial susceptibility profile, analyses of β-lactamase genes (blaTEM, blaSHV,blaCTX-MblaKPC, blaVIM, blaIMP, and blaSPM), plasmidial profile and ERIC-PCR (Enterobacterial repetitive intergenic consensus-polymerase chain reaction). RESULTS: ERIC-PCR and plasmidial analysis grouped the isolates in 17 and 19 patterns, respectively. Six isolates from one hospital presented the same pattern by ERIC-PCR, indicating clonal dissemination. All isolates presented blaSHV, 62.5% presented blaCTX-M-2, 29% blaTEM, and 41.7% blaKPC. Metallo-β-lactamase genes blaand blawere not detected. Eleven isolates were identified carrying at least 3 β-lactamase studied genes, and 2 isolates carried blaSHVblaTEM, blaCTX-M-2 and blaKPC simultaneously. CONCLUSIONS: The accumulation of resistance genes in some strains, observed in this study, imposes limitations in the therapeutic options available for the treatment of infections caused by K. pneumoniae in Recife, Brazil. These results should alert the Brazilian medical authorities to establish rigorous methods for more efficiently control the dissemination of antimicrobial resistance genes in the hospital environment.

INTRODUÇÃO: A prevalência de cepas de Klebsiella pneumoniae resistentes a cefalosporinas e carbapenêmicos está aumentando no Brasil, com sérias consequências em termos de desfechos dos pacientes e cuidados gerais. MÉTODOS: Este estudo caracterizou 24 isolados clínicos de K. pneumoniae provenientes de dois hospitais de Recife, Brasil, através do perfil de susceptibilidade a antimicrobianos, análise de genes de β-lactamase (blaTEM,blaSHV,blaCTX-MblaKPC,blaVIM, blaIMP,and blaSPM), perfil plasmidial e ERIC-PCR (Enterobacterial repetitive intergenic consensus-polymerase chain reaction). RESULTADOS: A análise da ERIC-PCR e do perfil plasmidial agrupou os isolados em 17 e 19 perfis, respectivamente. Seis isolados de um hospital apresentaram o mesmo padrão de ERIC-PCR, indicando disseminação clonal. Todos os isolados apresentaram blaSHV, 62,5% apresentaram blaCTX-M-2, 29% blaTEM e 41,7% blaKPC. Genes de metalo-β-lactamase blaVIM, blaIMP e blaSPM não foram detectados. Onze isolados foram identificados carreando, pelo menos, três dos genes de β-lactamase estudados, dentre estes, dois isolados continham blaSHV,blaTEM, blaCTX-M-2 e blaKPC simultaneamente. CONCLUSÕES: O acúmulo de genes de resistência em algumas cepas, observado nesse estudo, impõem limitações nas opções terapêuticas disponíveis para o tratamento de infecções causadas por K. pneumoniae em Recife, Brasil. Estes resultados devem alertar as autoridades médicas brasileiras para estabelecer rigorosos métodos para controlar eficientemente a disseminação de genes de resistência a antimicrobianos no ambiente hospitalar.