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An outbreak of bloodstream infection (BSI) caused by members of the Burkholderia cepacia complex (Bcc) took place from March 2012 until April 2014 involving thirteen patients. Aim. To describe an outbreak investigation of BSI Bcc and showing how genetic sequencing tools contributed to confirm the hypothesis of extrinsic contamination proposed by an observational study. Methods. The Infection Control Department revised and reinforced good practices of infusion therapy and catheter care, visits to affected wards, a case control study, and environmental screening based on the case-control findings. Results. Data from the case-control study found an association of cases with central venous catheter (OR 1.36; CI 1.15-1.67) and intravenous cisatracurium use (OR 10.75; CI 1.67-68.89). Visits to the operatory block revealed problems related to the cold chain used for the preservation of thermolabile cisatracurium. We could not retrieve Bcc from environmental samples using classic microbiology. New samples from the same surfaces were obtained for genetic sequencing. Bcc was identified in the cooler box, refrigerator and reusable ice packages. Conclusion. Environmental screening using genetic sequencing proved to be a useful tool for confirming our hypothesis of extrinsic contamination raised by the case-control study. [ABSTRACT FROM AUTHOR]

The growing challenge of antimicrobial resistance to antibiotics requires novel synthetic drugs or new formulations for old drugs. Here, cationic nanostructured particles (NPs) self-assembled from cationic bilayer fragments and polyelectrolytes are tested against four multidrug-resistant (MDR) strains of clinical importance. The non-hemolytic poly(diallyldimethylammonium) chloride (PDDA) polymer as the outer NP layer shows a remarkable activity against these organisms. The mechanism of cell death involves bacterial membrane lysis as determined from the leakage of inner phosphorylated compounds and possibly disassembly of the NP with the appearance of multilayered fibers made of the NP components and the biopolymers withdrawn from the cell wall. The NPs display broad-spectrum activity against MDR microorganisms, including Gram-negative and Gram-positive bacteria and yeast. [ABSTRACT FROM AUTHOR]

Objectives: Rapidly growing mycobacteria (RGM) have emerged as important pathogens in clinical settings, associated with esthetic procedures and postsurgical infections, pulmonary infections among cystic fibrosis patients, and other structural pulmonary diseases. Microorganisms belonging to Mycobacterium abscessus-Mycobacterium chelonae and to Mycobacterium fortuitum groups have frequently been associated with outbreaks and various epidemics. In the present study, RGM strains were characterized in order to investigate molecular markers based on proteomic analysis. Methods: Multilocus enzyme electrophoresis (MLEE) was used for species identification and clonal analysis of RGM recovered from postsurgical wound infections during an epidemic. The study included 30 M. abscessus subsp. bolletii clinical isolates, most belonging to the BRA100 clone (epidemic in Rio de Janeiro city), as well as 16 RGM ATCC reference strains. Results: Molecular typing allowed the detection of diversity in the studied population and revealed species-specific isoenzymatic patterns. Additionally, the clonal relationship among M. abscessus subsp. bolletii outbreak isolates, as examined using MLEE, was markedly consistent. Conclusions: Isoenzymatic characterization was found to be a useful molecular tool to identify RGM species and to determine the relatedness among closely related M. abscessus subsp. bolletii isolates. This may be considered a powerful approach for epidemiological studies on RGM. [ABSTRACT FROM AUTHOR]

Objective: Investigate clonal dissemination of nosocomial multidrug-resistant Pseudomonas aeruginosa isolates within and between Brazilian intensive care units, which participated in the MYSTIC Program Brazil 2002., Methods: Thirty-six P. aeruginosa isolates resistant to meropenem or imipenem plus at least two of the following drugs: ciprofloxacin, cefepime, ceftazidime or piperacillin/tazobactam were isolated during 2002 at 4 centres in São Paulo and 1 centre in Brasília. Chromosomal restriction fragments obtained with SpeI were separated by pulsed-field gel electrophoresis (PFGE). Electrophoretic patterns were analyzed with GelCompar II v. 2.5., Results: Five major clones were identified (A, B, C, D, G). Clone A was constituted by 8 isolates with indistinguishable PFGE pattern present in 2 centres. Clone B was constituted by 4 indistinguishable isolates predominant in centre 6. Clone C had 3 indistinguishable isolates, with closely related clones (C1-3). Also, Clone D had 3 indistinguishable isolates, with closely related (D1) and possibly related (D2/D3) clones. Clones C and D were present in centre 1. Clone G was constituted by 2 indistinguishable isolates and was present in centre 7. Finally, 8 isolates were unique. Isolates from Centre 4 were unique., Conclusions: Clonal dissemination was detected within (clones A, B, C, D, and G) and between centres (clone A). These findings are important when analyzing surveillance data, since susceptibility rates may be significantly affected by the dissemination of a resistant clone.