High mortality by nosocomial infections caused by carbapenem-resistant P. aeruginosa in a referral hospital in Brazil: facing the perfect storm.

Introduction. Carbapenem-resistant Pseudomonas aeruginosa is responsible for increased patient mortality.Gap Statement. Five and 30 day in-hospital all-cause mortality in patients with P. aeruginosa infections were assessed, followed by evaluations concerning potential correlations between the type III secretion system (TTSS) genotype and the production of metallo-ß-lactamase (MBL).Methodology. This assessment comprised a retrospective cohort study including consecutive patients with carbapenem-resistant infections hospitalized in Brazil from January 2009 to June 2019. PCR analyses were performed to determine the presence of TTSS-encoding genes and MBL genes.Results. The 30-day and 5-day mortality rates for 262 patients were 36.6 and 17.9 %, respectively. The unadjusted survival probabilities for up to 5 days were 70.55 % for patients presenting exoU-positive isolates and 86 % for those presenting exo-negative isolates. The use of urinary catheters, as well as the presence of comorbidity conditions, secondary bacteremia related to the respiratory tract, were independently associated with death at 5 and 30 days. The exoS gene was detected in 64.8 % of the isolates, the presence of the exoT and exoY genes varied and exoU genes occurred in 19.3 % of the isolates. The exoU genotype was significantly more frequent among multiresistant strains. MBL genes were not detected in 92 % of the isolates.Conclusions. Inappropriate therapy is a crucial factor regarding the worse prognosis among patients with infections caused by multiresistant P. aeruginosa, especially those who died within 5 days of diagnosis, regardless of the genotype associated with TTSS virulence.

Molecular characterization and clonal dynamics of nosocomial blaOXA-23 producing XDR Acinetobacter baumannii.

The emergence of infections associated to new antimicrobial resistance in Acinetobacter baumannii (Ab) genotypes represents a major challenge. In this context, this study aimed to determine the diversity of resistance mechanisms and investigate clonal dissemination and predominant sequence types (STs) in multidrug-resistant Ab strains of clinical (tracheal aspirate, n = 17) and environmental (surface, n = 6) origins. Additionally, the major clones found in clinical (A) and environmental (H) strains had their complete genomes sequenced. All strains were submitted to polymerase chain reactions (PCR) for the detection of the ISAba1/blaOXA-51-like and ISAba1/blaOXA-23-like genes, while the expression of genes encoding the carO porin, AdeABC (adeB), AdeFGH (adeG), and AdeIJK (adeJ) efflux pumps was determined by real time PCR (qPCR). Most of the strains were characterized as extensively drug-resistant (XDR) with high minimal inhibitory concentrations (MICs) detected for tigecycline and carbapenems. Associations between ISAba1/OXA-51 and ISAba1/OXA-23 were observed in 91.3% and 52.2% of the strains, respectively. Only the adeB gene was considered hyper-expressed. Furthermore, most of the strains analyzed by the MuLtilocus Sequence-Typing (MLST) were found to belong to the clonal complex 113 (CC113). In addition, a new ST, ST1399, belonging to CC229, was also discovered herein. Strains analyzed by whole genome sequencing presented resistance genes linked to multidrug-resistance phenotypes and confirmed the presence of Tn2008, which provides high levels carbapenem-resistance.

Multidrug Resistance Related to Biofilm Formation in Acinetobacter baumannii and Klebsiella pneumoniae Clinical Strains from Different Pulsotypes.

The emergence of Acinetobacter baumannii and Klebsiella pneumoniae strains in the hospital environment has been associated with the presence of multiple genetic elements, virulence factors and the ability to form biofilms. This study evaluated the biofilm formation ability of clinical and environmental A. baumannii and K. pneumoniae strains, isolated from various sources and presenting different molecular characteristics, resistance profiles and pulsed-field gel electrophoresis patterns. Fifty-three isolates were recovered from 2009 to 2014 in a Brazilian university hospital. Investigation of biofilm formation was performed for 10 strains of each species assessed by an initial adhesion assay, biofilm cell concentration and biofilm biomass, evaluated by quantitative assays in replicates, in three independent experiments. All strains of A. baumannii were able to attach to polystyrene plates, although two strains adhered to a lesser degree than the control. K. pneumoniae strains showed opposite behaviour, where only three strains adhered significantly when compared to the control. Quantitative evaluation revealed that in five A. baumannii and four K. pneumoniae isolates the biomass production could be characterised as moderate. None of the isolates were strong biofilm producers. Our results demonstrate: (1) biofilm formation is a heterogeneous property amongst A. baumannii and K. pneumoniae clinical strains and it was not associated with certain clonal types; (2) no relationship between multidrug resistance and biofilm production was observed; (3) more virulent K. pneumoniae strains tended to present higher production of biofilm.

Occurrence of bloodstream infection with different types of central vascular catheter in critically neonates.

OBJECTIVE: The aim of this research was to assess the incidence of CVC-associated/related to bloodstream infection (BSI) to different types of CVC, by classes of neonatal birth weight. METHODS: The research was conducted in the Neonatal Intensive Care Unit of Uberlandia University Hospital from April/2006 through April/2008. The population analyzed comprised neonates who had at least one CVC placed for longer than 24h, followed-up through epidemiologic vigilance "National Healthcare Safety Network". Patients were followed daily from their entry into the study to their discharge or death. RESULTS: At birth, 50.7% of neonates had low weight (< or = 1500g), 24.5% between 1501 and 2500g and 24.8% over 2500g. The highest density of CVC use (0.96) was found in neonates with birth weight ranging from 751g to 1000g. The incidence of CVC-associated/related to BSI was 13.0 and 2.1 per 1000 days CVC, respectively, and the higher representativeness in the weight group of 1501-2500g (15.8) and < or = 750g (3.3), respectively. A higher proportion of CVC-associated to BSI was observed in PICC (6.0) than in the other CVCs (P<0.01). Coagulase negative Staphylococcus was the most common microorganism (39.7%) in BSI, followed by Staphylococcus aureus (24. 6%) and Gram-negative bacilli (19.2%). CONCLUSION: Although neonates weighing less than 750g comprise the group with lower representativeness at the unit (5.4%), they reveal the highest CVC related to BSI incidence rate (3.3/1000 days CVC).

[Risk factors associated with colonization by Candida spp in neonates hospitalized in a Neonatal Intensive Care Unit in Brazil]. / Fatores de risco associados à colonização por Candida spp em neonatos internados em uma Unidade de Terapia Intensiva Neonatal brasileira.

The objectives of this study were to investigate the participation of Candida albicans and non-albicans as colonization and sepsis agents, along with the risk factors associated with the neonates in the neonatal intensive care unit of the clinical hospital of the Federal University of Uberlândia. Epidemiological surveillance was implemented through the National Healthcare Safety Network between August 2007 and April 2008. The incidence rate for sepsis with microbiological criteria was 6.7/1,000 patients/day, which was shown as only one case of candidemia. Approximately 19% of the neonates were colonized by Candida, which was identified as Candida albicans (50%) and Candida not-albicans (50%). The significant risk factors for Candida spp colonization were gestational age of between 26 and 30 weeks, previous antibiotic use and umbilical central vascular catheter. The overall mortality among the neonates hospitalized with sepsis over the study period was 11.8%. However, the neonate with candidemia did not die.