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Aims To investigate Pseudomonas aeruginosa isolates from a hospital wastewater treatment plant ( HWTP), focusing on enzyme-based mechanisms of β-lactams resistance and the genetic relatedness among isolates. Methods and Results Forty-one Ps. aeruginosa strains recovered from a HWTP were identified by amplification of 16S rRNA gene. β-lactamase production was screened by disc diffusion, CHROMagar extended-spectrum β-lactamase (ESBL) and β-lactamase strips. β-lactamase and ESBL producing isolates were investigated by PCR for the presence of ESBL, metallo- β-lactamase and Klebsiella pneumoniae carbapenemase encoding genes. Thirty-four isolates (83%) were resistant to at least one antibiotic belonging to three or more classes. Out of these 34 isolates, 28 (82%) were classified as multidrug-resistant (MDR) and 6 (18%) extensively drug-resistant (XDR). Genetic relatedness by Enterobacterial Repetitive Intergenic Consensus sequence-PCR and Multilocus sequence typing analysis showed 20 distinct profiles and 15 sequencing types respectively. Clonal Complex 244 (CC244) shows the pathogenic potential of this clone carrying MDR and XDR strains from clinical, environmental and hospital waste sources. Conclusions Our results suggest that treatment facilities for hospital wastewater can stimulate the increase of antimicrobial resistance bacteria and genes. Significance and Impact of the Study The great genetic diversity of Ps. aeruginosa recovered from HWTP constantly released into aquatic systems allow the spread of antimicrobial-resistant organisms and genes. [ABSTRACT FROM AUTHOR]

We examined the environmental dissemination of Acinetobacter nosocomialis multilocus sequence typing clonal complex 260/71 in Rio de Janeiro, Brazil, including water from a dam and food samples. The increasing use of sequence based methods has demonstrated a large, previously unpredicted, dissemination of bacteria that may serve as opportunistic pathogens.

The main objective of this study was to assess the frequency and possible sources of colonization and infection by Acinetobacter in the intensive care unit (ICU) of a university hospital in Rio de Janeiro, Brazil, and characterize the isolates for relatedness to internationally and locally disseminated lineages. Patients consecutively admitted to the ICU from April 2007 to April 2008 were screened for colonization and infection. Species were identified by rpoB sequencing. The presence of acquired and intrinsic carbapenemase genes was assessed by polymerase chain reaction (PCR). Strains were typed by random amplification of polymorphic DNA (RAPD)-PCR, pulsed-field gel electrophoresis, and multilocus sequence typing (MLST) using the schemes hosted at the University of Oxford (UO) and Institut Pasteur (IP). Of 234 patients, 98 (42%) had at least one specimen positive for the Acinetobacter isolate, and 24 (10%) had infection. A total of 22 (92%) infections were caused by Acinetobacter baumannii and one each (4%) by Acinetobacter nosocomialis and Acinetobacter berezinae. A. baumannii isolates from 60 patients belonged to RAPD types that corresponded to MLST clonal complexes (CCs) 109/1 (UO/IP scheme, known as International Clone I), CC 110/110 (UO/IP), CC 113/79 (UO/IP), and CC 104/15 (UO/IP). Most CCs were carbapenem resistant and carried the bla(OXA-23)-like gene. Strains were introduced by patients transferred from other wards of the same hospital (11 patients, 18%) or acquired from cross-transmission within the ICU (49 patients, 82%). A. nosocomialis lineage sequence type 260 colonized 10% of the whole study population. A. baumannii have become established in this hospital as a part of a global epidemic of successful clones. Once introduced into the hospital, such clones have become entrenched among patients in the ICU.