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We describe an outbreak caused by KPC-2-and IMP-10-producing Serratia marcescens isolates in a Brazilian teaching hospital. Tigecycline was the only active antimicrobial agent tested. The bla IMP-10 gene was located in a new class 1 integron, named In990, carried by a nonconjugative plasmid, in contrast to bla KPC-2 .

The global spread of carbapenem-resistant Acinetobacter baumannii (A. baumannii) strains has restricted the therapeutic options available to treat infections due to this pathogen. Understanding the prevalence of such infections and the underlying genetic mechanisms of resistance may help in the implementation of adequate measures to control and prevent acquisition of nosocomial infections, especially in an intensive care unit setting. This study describes the molecular characteristics and risk factors associated with OXA-23-producing A. baumannii infections. A case-control study was undertaken from September/2013 to April/2015. Acquisition of OXA-23-producing A. baumannii was found to be associated with the use of nasogastric tubes, haemodialysis, and the use of cephalosporins. These isolates were only susceptible to amikacin, gentamicin, tigecycline, and colistin, and contained the ISAba1 insertion sequence upstream ofblaOXA-23 and blaOXA-51 genes. Twenty-six OXA-23-producing A. baumannii strains belonged to the ST79 (CC79) clonal group,and patients infected or colonised by these isolates had a higher mortality rate (34.6%). In conclusion, this study showed a dissemination of OXA-23-producing A. baumannii strains that was associated with several healthcare-related risk factors and high mortality rates among intensive care unit patients.

The number of new syphilis cases in Brazil has risen alarmingly in recent years. However, there is limited data regarding syphilis prevalence in the Brazilian prison population. To facilitate the development of effective interventions, a cross-sectional study was undertaken to determine the prevalence of infection, active syphilis, and associated risk factors among Brazilian prisoners. We administered a questionnaire to a population-based sample of prisoners from 12 prisons in Central-West Brazil and collected sera for syphilis testing, from January to December 2013. Univariable and multivariable regression analyses were performed to assess associations with active syphilis. We recruited 3,363 prisoners (men: 84.6%; women: 15.4%). The overall lifetime and active syphilis prevalences were 10.5% (9.4% among men; 17% among women, < 0.001) and 3.8% (2% among men; 9% among women, < 0.001), respectively. The variables associated with active syphilis in men prisoners were homosexual preference, history of sexually transmitted infections, and human immunodeficiency virus status. Among women, the factors were sex with intravenous drug users, genital ulcer disease, and previous incarceration. Despite the high prevalence of active syphilis, 88.5% reported unawareness of their serological status and 67% reported unprotected sexual practices. Women had the highest rates of infection, including them in a high-risk group for the development of syphilis during pregnancy. Thus, implementing screening programs to enable continuous measures of control and prevention of infection in the prison environment, mainly in women institutions, is important to prevent severe forms of this disease and congenital infections.

This study describes the molecular characteristics and risk factors associated with carbapenemresistant Klebsiella pneumoniae strains. Risk factors associated with KPC-producing K. pneumoniae strains were investigated in this case-control study from May 2011 to May 2013. Bacterial identification was performed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility was determined by broth microdilution. Carbapenemase production was assessed by both modified Hodge test (MHT) and ertapenem hydrolysis using MALDI-TOF MS. The presence of b-lactamase-encoding genes was evaluated by PCR and DNA sequencing. Alterations in genes encoding K. pneumoniae outer membrane proteins were analysed by PCR and DNA sequencing as well as SDS-PAGE. Genetic relatedness among strains was determined by pulsed-field gel electrophoresis. This study included 94 patients. Longer hospitalisation, mechanical ventilation, catheters, and previous surgery were associated with KPC-producing K. pneumoniae. Sixty-eight strains showed resistance to carbapenems. Carbapenemase production was detected by MHT in 67 K. pneumoniae strains and by MALDI-TOF MS in 57. The presence of the bla KPC-2 gene was identified in 57 strains. The bla KPC-2 gene was not found in 11 carbapenem-resistant K. pneumoniae; instead, the bla CTX-M-1-like , bla CTX-M-2-like , bla CTX-M-8 like , bla CTX-M-14-like and bla SHV-like genes associated with OmpK35 and OmpK36 alterations were observed. Thirty-three KPC-producing K. pneumoniae strains were clonally related, and patients infected with these strains had a higher mortality rate (78.78 %). Our results show that KPC-producing K. pneumoniae was associated with several healthcare-related risk factors, including recent surgery.

Introduction: The increase in the prevalence of multidrug-resistant Acinetobacter baumannii infections in hospital settings has rapidly emerged worldwide as a serious health problem. Methods: This review synthetizes the epidemiology of multidrug-resistant A. baumannii, highlighting resistance mechanisms. Conclusions: Understanding the genetic mechanisms of resistance as well as the associated risk factors is critical to develop and implement adequate measures to control and prevent acquisition of nosocomial infections, especially in an intensive care unit setting.

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Multidrug resistance prompts the search for new sources of antibiotics with new targets at bacteria cell. To investigate the antibacterial activity of Cinnamomum cassia L. essential oil (CCeo) alone and in combination with antibiotics against carbapenemase-producing Klebsiella pneumoniae and Serratia marcescens. The antimicrobial susceptibility of the strains was determined by Vitek ® 2 and confirmed by MALDI-TOF/TOF. The antibacterial activity of CCeo and its synergism with antibiotics was determined using agar disk diffusion, broth microdilution, time-kill, and checkboard methods. The integrity of the bacterial cell membrane in S. marcescens was monitored by protein leakage assay. CCeo exhibited inhibitory effects with MIC = 281.25 μg.mL-1. The association between CCeo and polymyxin B showed a decrease in terms of viable cell counts on survival curves over time after a 4 hour-treatment with a FIC index value of 0.006. Protein leakage was observed with increasing concentrations for CCeo and CCeo + polymyxin B treatments. CCeo showed antibacterial activity against the studied strains. When associated with polymyxin B, a synergistic effect was able to inhibit bacterial growth rapidly and consistently, making it a potential candidate for the development of an alternative treatment and drug delivery system for carbapenemase-producing strains.