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Aim The current study was conducted to determine the antimicrobial resistance profile and genetic relatedness of Aeromonas sp. isolated from healthcare and urban effluents, wastewater treatment plant (WWTP) and river water. Methods and Results We detected the presence of genes conferring resistance to β‐lactam, quinolone and aminoglycoside. Multilocus sequence typing was carried out to differentiate the strains, and multilocus phylogenetic analysis was used to identify the species. A total of 28 cefotaxime‐resistant Aeromonas sp. strains were identified, harbouring uncommon Guiana‐extended‐spectrum (GES)‐type β‐lactamases (GES‐1, GES‐5, GES‐7 and GES‐16). Multidrug‐resistant Aeromonas sp. were found in hospital wastewater, WWTP and sanitary effluent, and A. caviae was identified as the most prevalent species (85·7%). Conclusion The release of untreated healthcare effluents, presence of antimicrobials in the environment, in addition to multidrug‐resistant Aeromonas sp., are all potential factors for the spread of resistance. Significance and Impact of the Study We identified a vast repertoire of antimicrobial resistance genes (ARG) in Aeromonas sp. from diverse aquatic ecosystems, including those that encode enzymes degrading broad‐spectrum antimicrobials widely used to treat healthcare‐associated infections. Hospital and sanitary effluents serve as potential sources of bacteria harbouring ARG and are a threat to public health.

Carbapenem-resistant A. baumannii infections mortality is high. Alternative antimicrobial therapy (doxycycline) for selected patients with carbapenem-resistant A. baumannii infection should be considered.

Objective To describe the clinical and epidemiological features of patients with and without sepsis at critical care units of a public hospital. Methods A cross-sectional study was carried out from May 2012 to April 2013. Clinical and laboratory data of patients with and without sepsis in the intensive care units were reviewed of medical records. Results We evaluated 466 patients, 58% were men, median age was 40 years, and 146 (31%) of them were diagnosed with sepsis. The overall mortality was 20% being significantly higher for patients with sepsis (39%). The factors associated with intensive care unit mortality were the presence of sepsis (OR: 6.1, 95%CI: 3.7-10.5), age (OR: 3.6, 95%CI: 1.4-7.2), and length of hospital stay (OR: 0.96, 95%CI: 0.94-0.98). Pulmonary (49%) and intra-abdominal (20%) infections were most commonly identified sites, and coagulase-negative staphylococci and enteric Gram negative bacilli the most frequent (66%) pathogens isolated. Conclusion Although the impact of sepsis on mortality is related to patients’ clinical and epidemiological characteristics, a critical evaluation of these data is important since they will allow the direct implementation of local policies for managing this serious public health problem.

Introduction. This study aimed to evaluate different methods for differentiation of species of coagulase-negative staphylococci (CoNS) that caused infections in hospitalized immunocompromised patients. Methods. A total of 134 CoNS strains were characterized using four different methods. Results. The results of matrix assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) analysis were in complete agreement with those of tuf gene sequencing (kappa index = 1.00 . The increasing incidence of CoNS hospitalacquired infections emphasizes the need for accurate and rapid identification of Staphylococcus at the species level. Although the ability to distinguish between these pathogens is clinically relevant, a number of laboratory limitations still exist 1,3 . Molecular methods are currently favored for accurate identification and several target genes, such as tuf gene, exhibit high discriminatory power 4 . The aim of this study was to compare the ability of matrix-assisted laser desorption/ionization timeof-flight mass spectrometry (MALDI-TOF MS) (Microflex LT instrument, Bruker Daltonics, Bremen, Germany) and three other identification methods to differentiate between CoNS samples.A total of 134 CoNS clinical isolates from the blood cultures (112) and catheter tips (22) of patients hospitalized in a tertiary care teaching Hospital in Curitiba, Brazil were studied. The discriminatory power of MALDI-TOF MS was compared to that of the gold standard tuf gene sequencing method, an automated method (Vitek ® 2 Compact, bioMérieux, Marcy l'Etoile, France), and a conventional method for all CoNS included in the study. In addition, the minimum inhibitory concentrations (MICs) of the antimicrobials oxacillin, daptomycin, linezolid, and vancomycin were evaluated and the presence of the mecA gene was determined by PCR for all strains.All bacterial isolates were preliminarily identified by catalase, coagulase, and deoxyribonuclease tests. In addition, the disk diffusion assay was used to determine susceptibility to fosfomycin (200µg) and desferrioxamine (300µg) 5 . Subsequently, the strains were evaluated using the conventional method proposed by Cunha et al., for distinguishing between species not identified by the previous tests 3 . S. epidermidis ATCC 12228 was used as the control strain. Finally, the Vitek ® 2 Compact automated system was used as per the manufacturer's instructions; the acceptable criterion for identification was set at 93-99% probability.For MALDI-TOF MS analysis, a loopful of cells from a fresh overnight pure culture was processed as previously described 6 . The obtained mass spectra were analyzed using the Microflex LT instrument with MALDI Biotyper 3.0 software. The identification score cutoff value was set at ≥1.8 7 .

Extended-spectrum β-lactamases (ESBL) are plasmid-mediated enzymes that hydrolyze cephalosporins and monobactams. The lack of a standard method to detect ESBL in Enterobacter spp. has led to underestimating its frequency. The aim of this study was to evaluate ESBL detection in Enterobacter spp. By the double-disk synergy test (DDST) and combined disk test (CDT) assay using cefepime, cefotaxime, and ceftazime as substrates for ESBL, plus AmpC inhibitors in different associations. A total of 83 Enterobacter spp. ESBL and 31 non-ESBL Enterobacter spp. were tested, and a cutoff point ≥3 mm was defined using a receiver operating characteristic (ROC) curve for combined disc methods. All tests showed 100% specificity. The sensitivity was 89.2% for DDST and CDT without AmpC inibitor, 90.4% in the combined disc test in Mueller-Hinton agar containing phenylboronic acid (CDT-PBAA), and 94% in the combined disc test in Mueller-Hinton agar containing cloxacillin (CDT-CLXA). Cefepime was the best substrate, mainly when AmpC inhibitors were not used. However, superior results were achieved when all cephalosporins were evaluated together. In conclusion, to improve ESBL detection in Enterobacter spp., some modifications in phenotypic tests are needed, such as to reduce the distance between the discs to 20 mm in DDST, to use a cutoff point for ≥3 mm on the CDT, and to include a cefepime disk or an inhibitor of AmpC in all tests.