Ana Paula D’Alincourt Carvalho-Assef

Dissemination of multidrug-resistant Acinetobacter baumannii genotypes carrying blaOXA-23 collected from hospitals in Rio de Janeiro, Brazil

The present study reports the dissemination of multidrug-resistant (MDR) OXA-23-producing Acinetobacter baumannii clones throughout hospitals in Rio de Janeiro, Brazil. A total of 110 imipenem-resistant A. baumannii isolates were obtained from January 2006 to September 2007 in eight hospitals. The modified Hodge test was performed to screen for carbapenemase production. Polymerase chain reaction (PCR) and DNA sequencing were performed for the detection of bla(IMP), bla(VIM), bla(OXA-23-like), bla(OXA-24-like), bla(OXA-58) and the class 1 integron. Isolates were typed by pulsed-field gel electrophoresis (PFGE) following digestion with ApaI. All the isolates were MDR and 96 (87.3%) produced the carbapenemase OXA-23. No isolates produced OXA-24, OXA-58 or the metallo-beta-lactamases IMP and VIM. The class 1 integron was absent in all isolates. The A. baumannii isolates were separated into five genotypes, with the highest prevalence of genotype A (71.8%) followed by genotype B (22.7%). Genotype A was present in seven hospitals, whilst genotype B had spread in five hospitals. The OXA-23-producing isolates belonged to all genotypes. The presence of MDR OXA-23-producing A. baumannii in different hospitals in Rio de Janeiro emphasises the need to control the use of carbapenems and to prevent the spread of these organisms in Rio de Janeiro.

Achromobacter xylosoxidans: Characterization of Strains in Brazilian Cystic Fibrosis Patients

ABSTRACT We investigated the possibility of cross-infection among cystic fibrosis patients in two Brazilian reference centers. Achromobacter xylosoxidans isolates (n = 122) were recovered over a 5-year period from 39 patients. Isolates were genetically heterogeneous, but one genotype was present in 56% of the patients, suggesting that cross-infection may have occurred.

Characterization of carbapenem-resistant Acinetobacter baumannii in Brazil (2008–2011): countrywide spread of OXA-23–producing clones (CC15 and CC79)

The study investigated the genetic relationship of carbapenem-resistant Acinetobacter baumannii clinical isolated from inpatients during 2008-2011 from 11 Brazilian states. Antimicrobial susceptibility profile was determined by disc diffusion method and Etest. Polymerase chain reaction was applied for carbapenemase genes, and ISAba1. Isolates were subjected to pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) for molecular typing. Most of the isolates showed high resistance rates to antibiotics tested. The blaOXA-51-like gene was found in all isolates, and 146 (94.2%) isolates were positive for blaOXA-23-like. In the most OXA-23-producing isolates, the blaOXA-23-like gene was accompanied by ISAba1. A total of 146 OXA-23-producing isolates were clustered into 28 genotypes by PFGE. Molecular analysis by MLST identified 13 sequence types (STs). The most prevalent PFGE profiles were designated as ST15 (CC15), ST1 (CC1), and ST79 (CC79). This study showed the widespread of clonal complexes of A. baumannii harboring the blaOXA-23-like gene in different Brazilian states.

Molecular epidemiology of KPC-2–producing Enterobacteriaceae (non–Klebsiella pneumoniae) isolated from Brazil

In Brazil, since 2009, there has been an ever increasing widespread of the bla(KPC-2) gene, mainly in Klebsiella pneumoniae. This study aims to assess the molecular epidemiology and genetic background of this gene in Enterobacteriaceae (non-K. pneumoniae) species from 9 Brazilian states between 2009 and 2011. Three hundred eighty-seven isolates were analyzed exhibiting nonsusceptibility to carbapenems, in which the bla(KPC-2) gene was detected in 21.4%. By disk diffusion and E-test, these isolates exhibited high rates of resistance to most of the antimicrobials tested, including tigecycline (45.6% nonsusceptible) and polymyxin B (16.5%), the most resistant species being Enterobacter aerogenes and Enterobacter cloacae. We found great clonal diversity and a variety of bla(KPC-2)-carrying plasmids, all of them exhibiting a partial Tn4401 structure. Therefore, this study demonstrates the dissemination of KPC-2 in 9 Enterobacteriaceae species, including species that were not previously described such as Pantoea agglomerans and Providencia stuartii.

Influence of biofilm formation in the susceptibility of Pseudomonas aeruginosa from Brazilian patients with cystic fibrosis.

Ferreira AG, Leão RS, Carvalho‐Assef APD, Folescu TW, Barth AL, Marques EA. Influence of biofilm formation in the susceptibility of Pseudomonas aeruginosa from Brazilian patients with cystic fibrosis. APMIS 2010; 118: 606–12.

Detection of the plasmid-mediated mcr-1 gene in clinical KPC-2-producing Escherichia coli isolates in Brazil

This study reports the first detection of mcr-1 in KPC-2-producing clinical E. coli isolates in Brazil and emphasises the importance of microbiological and molecular surveillance to avoid the spread of these genes in this country. The detection of successful E. coli clones containing mcr-1 and β-lactamase genes in conjugative plasmids highlights a possible joint dissemination of colistin and carbapenem resistance in Brazilian hospitals, where KPC is already worrisome.

Draft genome sequences of three NDM-1-producing Enterobacteriaceae species isolated from Brazil

The emergence of multidrug-resistant Enterobacteriaceae strains producing carbapenemases, such as NDM-1, has become a major public health issue due to a high dissemination capacity and limited treatment options. Here we describe the draft genome of three NDM-1-producing isolates: Providencia rettgeri (CCBH11880), Enterobacter hormaechei subsp. oharae (CCBH10892) and Klebsiella pneumoniae (CCBH13327), isolated in Brazil. Besides blaNDM-1, resistance genes to aminoglycosides [aadA1, aadA2, aac(6’)-Ib-cr] and quinolones (qnrA1, qnrB4) were observed which contributed to the multidrug resistance profile. The element ISAba125 was found associated to the blaNDM-1 gene in all strains.

Characterization of Achromobacter Species in Cystic Fibrosis Patients: Comparison of bla OXA-114 PCR Amplification, Multilocus Sequence Typing, and Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry

ABSTRACT Molecular methodologies were used to identify 28 Achromobacter spp. from patients with cystic fibrosis (CF). Multilocus sequence typing (MLST) identified 17 Achromobacter xylosoxidans isolates (all bla OXA-114 positive), nine Achromobacter ruhlandii isolates (all bla OXA-114 positive), one Achromobacter dolens isolate, and one Achromobacter insuavis isolate. All less common species were misidentified as A. xylosoxidans by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). Chronic colonization by clonally related A. ruhlandii isolates was demonstrated.

Detection of an NDM-1-producing Acinetobacter bereziniae strain in Brazil

This work was supported by Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ) and Oswaldo Cruz Institute (PAPES-FIOCRUZ).

Draft genome sequence of Acinetobacter pittii ST643 shared by cystic fibrosis patients.

Acinetobacter pittii has emerged as an important hospital pathogen that is associated with outbreaks and drug resistance. In cystic fibrosis (CF) patients, the detection of Acinetobacter spp. is rare; however, we isolated the A. pittii sequence type ST643 in several Brazilian CF patients treated in the same centre. The current study describes the draft genome of A. pittii ST643.