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1.
Article in English | LILACS | ID: biblio-1284447

ABSTRACT

This paper described the chemical compositions and antimicrobial activity of the essential oils from the leaves and stem of Amomum rubidumLamxay & N. S. Lý, collected from Bidoup Nui Ba National Park, Lam Dong, Vietnam. The essential oils were obtained by hydrodisitllation method while antimicrobial activity was evaluetd by microdilution broth susceptibility assay. The main constituents of the leaf essential oil were identified as 1,8-cineole (37.7%), δ-3-carene (19.5%) and limonene (16.3%) while δ-3-carene (21.9%), limonene (17.8%) and ß-phellandrene (14.6%) dominated in the stem essentialoil. The leaf and stem essential oils displayed stronger inhibition of Pseudomonas aeruginosa with MIC of 25 µg/mLand 50 µg/mL respectively. The stem essential oil was active against Candida albicans (MIC, 50 µg/mL) while both essential oils inhibited the growth of Fusarium oxysporum (MIC 50 µg/mL). This is the first report on chemical constituents and antimicrobial activity of the essential oils of A. rubidum.


Este artículo describe la composición química y la actividad antimicrobiana de aceites esenciales de las hojas y el tallo de Amomum rubidum Lamxay & N. S. Lý recolectados del Parque Nacional Bidoup Nui Ba, Lam Dong, Vietnam. Los aceites esenciales se obtuvieron mediante el método de hidrodisitilación, mientras que la actividad antimicrobiana se evaluó mediante un ensayo de susceptibilidad de caldo de microdilución. Los principales componentes del aceite esencial de la hoja se identificaron como 1,8-cineol (37,7%), δ-3-careno (19,5%) y limoneno (16,3%), mientras que δ-3-careno (21,9%), limoneno (17,8 %) y ß-felandreno (14,6%) dominaron en el aceite esencial del tallo. Los aceites esenciales de hoja y tallo mostraron una inhibición más fuerte de Pseudomonas aeruginosa con un MIC de 25 µg/mL y 50 µg/mL, respectivamente. El aceite esencial del tallo fue activo contra Candida albicans (MIC, 50 µg/mL) mientras que ambos aceites esenciales inhibieron el crecimiento de Fusarium oxysporum (MIC 50 µg/mL). Este es el primer informe sobre los componentes químicos y la actividad antimicrobiana de los aceites esenciales de A. rubidum.


Subject(s)
Oils, Volatile/pharmacology , Amomum/chemistry , Anti-Infective Agents/pharmacology , Pseudomonas aeruginosa/drug effects , Candida albicans/drug effects , Oils, Volatile/chemistry , Microbial Sensitivity Tests , Distillation , Chromatography, Gas , Plant Stems , Plant Leaves , Monoterpenes/analysis , Fusarium/drug effects , Anti-Infective Agents/chemistry
2.
Gac. méd. Méx ; 156(6): 604-609, nov.-dic. 2020. tab
Article in Spanish | LILACS | ID: biblio-1249973

ABSTRACT

Resumen Introducción: Existe poca información acerca de la efectividad de las combinaciones ceftolozano/tazobactam y ceftazidima/avibactam en cepas clínicamente relevantes aisladas en México. Objetivo: Determinar el perfil antimicrobiano de ambos antibióticos en nuestra comunidad. Método: El presente estudio de investigación fue prospectivo, descriptivo y transversal. Se incluyeron cepas clínicamente relevantes aisladas a partir de cultivos de cepa pura durante el periodo de agosto de 2018 a enero de 2019 en Mexicali, Baja California, México. Resultados: Se analizaron 74 cepas de enterobacterias y 19 cepas de Pseudomonas aeruginosa; el porcentaje de sensibilidad de ceftazidima/avibactam fue de 100 % contra enterobacterias y de 72.7 % contra Pseudomonas aeruginosa; el porcentaje de sensibilidad de ceftolozano/tazobactam fue de 90.5 % para enterobacterias y de 72.7 % para Pseudomonas aeruginosa. Conclusiones: Las combinaciones ceftolozano/tazobactam y ceftazidima/avibactam ofrecen buena sensibilidad antimicrobiana in vitro, tanto contra enterobacterias productoras de betalactamasas de espectro extendido como contra Pseudomonas aeruginosa. Se requieren más datos para valorar la respuesta clínica en pacientes que reciben esas combinaciones de antibióticos.


Abstract Introduction: There is limited information on the effectiveness of ceftolozane/tazobactam and ceftazidime/avibactam combinations on clinically relevant strains isolated in Mexico. Objective: To determine the antimicrobial profile of both antibiotic combinations in our community. Method: The present research study was prospective, descriptive and cross-sectional. Clinically relevant strains isolated from pure-strain cultures were included during the period from August 2018 to January 2019 in Mexicali, Baja California, Mexico. Results: 74 enterobacteriaceae and 19 Pseudomonas aeruginosa strains were analyzed; the percentage of sensitivity of ceftazidime/avibactam was 100 % for enterobacteriaceae and 72.7 % for Pseudomonas aeruginosa; the percentage of sensitivity of ceftolozane/tazobactam for enterobacteriaceae was 90.5 % and 72.7 % for Pseudomonas aeruginosa. Conclusions: The ceftolozane/tazobactam and ceftazidime/avibactam combinations offer good antimicrobial sensitivity in vitro, both for ESBL-producing enterobacteriaceae and Pseudomonas aeruginosa. More data are required to assess clinical response in patients receiving these antibiotic combinations.


Subject(s)
Humans , Pseudomonas aeruginosa/drug effects , Ceftazidime/therapeutic use , Cephalosporins/therapeutic use , Enterobacteriaceae/drug effects , Azabicyclo Compounds/therapeutic use , Anti-Bacterial Agents/therapeutic use , Pseudomonas aeruginosa/isolation & purification , Microbial Sensitivity Tests , Cross-Sectional Studies , Prospective Studies , Drug Combinations , Enterobacteriaceae/isolation & purification , Tazobactam/therapeutic use , Mexico
3.
Rev. Soc. Bras. Med. Trop ; 53: e20180498, 2020. tab
Article in English | LILACS | ID: biblio-1057281

ABSTRACT

Abstract INTRODUCTION: Pseudomonas aeruginosa is one of the main pathogens causing infection in intensive care units (ICUs) and usually presents antimicrobial resistance. METHODS: Data were obtained from ICUs between 2010 and 2013. RESULTS: P. aeruginosa had a prevalence of 14.5% of which 48.7% were multidrug resistant. We observed increasing resistance to carbapenems and polymyxin B and growing consumption of aminoglycosides, meropenem, ceftazidime, and polymyxin B. The regression impact between resistance and consumption was significant with respect to amikacin, imipenem, meropenem, and polymyxin B. CONCLUSIONS: Monitoring antimicrobial consumption and resistant microorganisms should be reinforced to combat antimicrobial- and multi-drug resistance.


Subject(s)
Humans , Pseudomonas aeruginosa/drug effects , Pseudomonas Infections/microbiology , Cross Infection/microbiology , Pseudomonas aeruginosa/isolation & purification , Microbial Sensitivity Tests , Prevalence , Drug Resistance, Multiple, Bacterial , Intensive Care Units , Anti-Bacterial Agents/pharmacology
4.
J. bras. pneumol ; 46(4): e20180294, 2020. tab, graf
Article in English | LILACS | ID: biblio-1134879

ABSTRACT

ABSTRACT Objective: Although various strategies have been proposed for eradicating Pseudomonas aeruginosa in patients with cystic fibrosis (CF), only a few employ multistep treatment in children colonized by that pathogen for the first time. The aim of this study was to describe the effectiveness of a three-phase eradication protocol, initiated after the first isolation of P. aeruginosa, in children with CF in Brazil. Methods: This was a retrospective real-life study in which we reviewed the medical records of pediatric CF patients in whom the eradication protocol was applied between June of 2004 and December of 2012. The three-phase protocol was guided by positive cultures for P. aeruginosa in airway secretions, and the treatment consisted of inhaled colistimethate and oral ciprofloxacin. Success rates were assessed after each phase, as well as cumulatively. Results: During the study period, 47 episodes of P. aeruginosa colonization, in 29 patients, were eligible for eradication. Among the 29 patients, the median age was 2.7 years, 17 (59%) were male, and 19 (65%) had at least one F508del allele. All 29 patients completed the first phase of the protocol, whereas only 12 and 6 completed the second and third phases, respectively. Success rates for eradication in the three treatment phases were 58.6% (95% CI: 40.7-74.5), 50.0% (95% CI: 25.4-74.6), and 66.7% (95% CI: 30.0-90.3), respectively. The cumulative success rate was 93.1% (95% CI: 78.0-98.1). Treatment failure in all three phases occurred in only 2 patients. Conclusions: In this sample of patients, the multistep eradication protocol was effective and had a high success rate.


RESUMO Objetivo: Embora várias estratégias de erradicação de Pseudomonas aeruginosa tenham sido propostas para pacientes com fibrose cística (FC), apenas algumas usaram um tratamento em fases e incluíram crianças na primeira colonização por esse patógeno. O objetivo deste estudo foi descrever a eficácia de um protocolo de erradicação em três fases em crianças com FC a partir do primeiro isolamento de P. aeruginosa no Brasil. Métodos: Estudo retrospectivo de vida real que avaliou prontuários de pacientes pediátricos com FC submetidos ao protocolo de erradicação entre junho de 2004 e dezembro de 2012. O protocolo em três fases foi orientado pela cultura positiva para P. aeruginosa de secreções das vias aéreas, utilizando-se colistimetato inalatório e ciprofloxacina oral no tratamento. As taxas de sucesso após cada fase e a de sucesso acumulado foram avaliadas. Resultados: Durante o período do estudo, 47 episódios de colonização por P. aeruginosa, em 29 pacientes, foram elegíveis para erradicação. Todos os 29 pacientes foram submetidos à primeira fase do protocolo (mediana de idade de 2,7 anos, 17 pacientes (59%) do sexo masculino e 19 (65%) com pelo menos um alelo F508del), sendo que 12 e 6 pacientes foram submetidos a segunda e terceira fases, respectivamente. As taxas de sucesso de erradicação nas três fases de tratamento foram de 58,6% (IC95%: 40,7-74,5), 50,0% (IC95%: 25,4-74,6) e 66,7% (IC95%: 30,0-90,3), respectivamente. A taxa de sucesso acumulado foi de 93,1% (IC95%: 78,0-98,1). Apenas 2 pacientes apresentaram falha do tratamento de erradicação. Conclusões: O primeiro isolamento de P. aeruginosa ocorreu em crianças de baixa idade. O protocolo de erradicação em fases foi efetivo com alta taxa de sucesso.


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Pseudomonas aeruginosa/drug effects , Pseudomonas Infections/drug therapy , Cystic Fibrosis/complications , Anti-Bacterial Agents/therapeutic use , Brazil , Clinical Protocols , Retrospective Studies
5.
Rev. chil. infectol ; 36(5): 551-555, oct. 2019. tab
Article in Spanish | LILACS | ID: biblio-1058080

ABSTRACT

Resumen Introducción: Pseudomonas aeruginosa es un patógeno oportunista asociado a alta morbi-mortalidad. Para cepas multi-resistentes (MDR), ceftolozano/tazobactam (CTZ) se ha autorizado por la Agencia Europea del Medicamento (EMA) para infecciones del tracto urinario complicadas, pielonefritis aguda e infecciones intra-abdominales complicadas. Objetivo: Determinar la sensibilidad a CTZ de P. aeruginosa MDR en muestras clínicas aisladas en el Hospital Universitario Puerto Real. Material y Métodos: Se estudió la sensibilidad según criterios EUCAST a CTZ de cepas de P. aeruginosa MDR, entre enero de 2015 y agosto de 2017. Los criterios de multi-resistencia fueron definidos por el Centers for Disease Control and Prevention. La sensibilidad antimicrobiana se obtuvo mediante sistema MicroScan® (Beckman Coulter). La sensibilidad a CTZ se determinó mediante tiras de gradiente (Liofilchem®, Werfen). Resultados: De 1253 cepas, 7% fueron MDR. Se estudió la sensibilidad de 78 cepas de P. aeruginosa MDR, de las cuales cinco (6,4%) resultaron resistentes a CTZ según criterios EUCAST. Conclusiones: En nuestro medio la resistencia in vitro a CTZ en cepas de P. aeruginosa MDR es aproximadamente 6%; CTZ es una opción de tratamiento de infecciones por cepas de P. aeruginosa MDR cuando no exista otra alternativa y se haya comprobado su sensibilidad in vitro.


Background: Pseudomonas aeruginosa is an opportunistic pathogen associated with high morbidity and mortality. For multidrug-resistant strains (MDR), ceftolozane/tazobactam (CTZ) has been authorized by the European Medicines Agency (EMA) for complicated urinary tract infections, acute pyelonephritis, and complicated intraabdominal infections. Aim: To determine the susceptibility to CTZ of P. aeruginosa MDR in isolated clinical samples at the University Hospital Puerto Real. Methods: The susceptibility according to the EUCAST to CTZ criteria of strains of P. aeruginosa MDR, between January 2015 and August 2017 has been studied. The multiresistance criteria were those defined by the Centers for Disease Control and Prevention. The antibiotic susceptibility was obtained by automated MicroScan® system (Beckman Coulter). Susceptibility to CTZ was determined using gradient strips (Liofilchem®, Werfen). Results: Of 1253 strains isolated, 7% presented MDR. We studied the susceptibility of a total of 78 strains of MDR P. aeruginosa, of which 5 (6.4%) were resistant to CTZ according to the EUCAST criteria. Conclusions: In our environment, the in vitro resistance to CTZ in MDR P. aeruginosa strains is approximately 6%. CTZ is an option for the treatment of infections by MDR P. aeruginosa when there is no other alternative and its in-vitro susceptibility has been proven.


Subject(s)
Pseudomonas aeruginosa/drug effects , Cephalosporins/pharmacology , Drug Resistance, Multiple, Bacterial/drug effects , Tazobactam/pharmacology , Anti-Bacterial Agents/pharmacology , Pseudomonas aeruginosa/isolation & purification , Reference Values , Mass Spectrometry , Microbial Sensitivity Tests , Reproducibility of Results , Real-Time Polymerase Chain Reaction
6.
Rev. chil. infectol ; 36(2): 180-189, abr. 2019. tab, graf
Article in Spanish | LILACS | ID: biblio-1003666

ABSTRACT

Resumen Dentro de las infecciones nosocomiales más frecuentes asociadas a bacterias multi-resistentes y de peor pronóstico, se encuentran las producidas por Pseudomonas aeruginosa. Esta bacteria posee una alta capacidad de adaptación a condiciones adversas como por ejemplo el pH y la osmolaridad de la orina. Pseudomonas aeruginosa es uno de los principales patógenos implicados en infecciones nosocomiales y de pacientes inmunosuprimidos. Esta bacteria se considera un agente infeccioso oportunista que posee diversos mecanismos de patogenicidad, así como de resistencia a antimicrobianos, lo que contribuye a la dificultad en el tratamiento de estas infecciones. En la presente revisión bibliográfica se analizan la taxonomía, los mecanismos de patogenicidad y genes de resistencia de P. aeruginosa. Así también, se abordan los factores microambientales de la infección urinaria producida por esta bacteria, haciendo un acercamiento al entendimiento de las bases fisiopatológicas de esta infección.


Among the most frequent nosocomial infections associated with polyresistant bacteria and with a worse prognosis, are those produced by Pseudomonas aeruginosa. This bacterium has a high capacity to adapt to adverse conditions such as pH and osmolarity of urine. Pseudomonas aeruginosa is one of the main pathogens involved in nosocomial infections and immunosuppressed patients. This bacterium is considered an opportunistic infectious agent that has diverse mechanisms of pathogenicity, as well as resistance to antimicrobials, which contributes to the difficulty in the treatment of these infections. In the present bibliographic review, the taxonomy, pathogenicity mechanisms and resistance genes of P. aeruginosa are analyzed. Likewise, the micro-environmental factors of the urinary infection produced by this bacterium are approached, making an approach to the understanding of the pathophysiological bases of this infection.


Subject(s)
Humans , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/pathogenicity , Pseudomonas Infections/microbiology , Pseudomonas Infections/drug therapy , Urinary Tract Infections/microbiology , Drug Resistance, Bacterial/drug effects , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/drug effects , Urinary Tract Infections/drug therapy , Biofilms/drug effects , Virulence Factors
7.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 17(1): 47-53, abr. 2019. ilus, tab
Article in Spanish | LILACS, BDNPAR | ID: biblio-1007944

ABSTRACT

Se evaluó la actividad sinérgica de los alcaloides crotsparina y esparsiflorina, aislados de Croton bomplandianum Baill. con los antibacterianos gentamicina y ciprofloxacina frente a Pseudomonas aeruginosa, microorganismo frecuentemente responsable de infecciones intrahospitalarias. Se empleó el método del "tablero de damas". Se encontraron combinaciones que presentaban efecto sinérgico, logrando la reducción de 87,5% de la CMI de gentamicina, mientras que para ciprofloxacina se logró una reducción del 25,0%. Esto abre interesantes perspectivas sobre el uso combinado de productos naturales puros y fármacos en uso clínico para el tratamiento de infecciones producidas por este microrganismo(AU)


Subject(s)
Pseudomonas aeruginosa/drug effects , Gentamicins/pharmacology , Ciprofloxacin/pharmacology , Croton , Alkaloids/pharmacology , Anti-Bacterial Agents/pharmacology , Gentamicins/isolation & purification , Drug Synergism , Alkaloids/chemistry
9.
Mem. Inst. Oswaldo Cruz ; 114: e190105, 2019. tab, graf
Article in English | LILACS | ID: biblio-1012671

ABSTRACT

BACKGROUND Healthcare-associated infections caused by bacteria such as Pseudomonas aeruginosa are a major public health problem worldwide. Gene regulatory networks (GRN) computationally represent interactions among regulatory genes and their targets. They are an important approach to help understand bacterial behaviour and to provide novel ways of overcoming scientific challenges, including the identification of potential therapeutic targets and the development of new drugs. OBJECTIVES The goal of this study was to reconstruct the multidrug-resistant (MDR) P. aeruginosa GRN and to analyse its topological properties. METHODS The methodology used in this study was based on gene orthology inference using the reciprocal best hit method. We used the genome of P. aeruginosa CCBH4851 as the basis of the reconstruction process. This MDR strain is representative of the sequence type 277, which was involved in an endemic outbreak in Brazil. FINDINGS We obtained a network with a larger number of regulatory genes, target genes and interactions as compared to the previously reported network. Topological analysis results are in accordance with the complex network representation of biological processes. MAIN CONCLUSIONS The properties of the network were consistent with the biological features of P. aeruginosa. To the best of our knowledge, the P. aeruginosa GRN presented here is the most complete version available to date.


Subject(s)
Humans , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/genetics , Pseudomonas Infections/immunology , Genes, Regulator/immunology , Brazil/epidemiology , Genes, MDR/genetics
10.
Int. braz. j. urol ; 44(6): 1234-1242, Nov.-Dec. 2018. graf
Article in English | LILACS | ID: biblio-975655

ABSTRACT

ABSTRACT Background: Formation of struvite stones is associated with urinary tract infection by urease-producing bacteria. Biogenic crystal growth in natural and synthetic materials is regulated by the action of inhibitors, ranging from small ions, molecules to large macromolecules. Materials and Methods: We report the dynamics of in vitro crystallization of struvite in presence of vitamin C in synthetic urine using single diffusion gel growth technique. Sodium metasilicate gel of specific gravity 1.05 and the aqueous solution of ammonium dihydrogen phosphate were used as the medium for growing the struvite crystals. The crystallization process was induced by a urease positive struvite stone associated Pseudomonas aeruginosa to mimic the infection leading to stone formation. The grown crystals were characterized by ATR-FTIR and powder XRD. The surface morphology was analysed through FE-SEM for comparison between treatments. Results: We observed decrease in number, dimension, and growth rate of struvite crystals with the increasing concentrations of vitamin C. Crystals displayed well-defined faces and dendritic morphology of struvite in both control and biogenic systems. Conclusion: The results strongly suggest that, vitamin C can modulate the formation of struvite crystals in the presence of uropathogenic bacteria.


Subject(s)
Humans , Pseudomonas aeruginosa/drug effects , Ascorbic Acid/pharmacology , Urine/microbiology , Vitamins/pharmacology , Calculi/prevention & control , Struvite/chemistry , Time Factors , Crystallization
11.
Med. infant ; 25(4): 299-302, diciembre 2018. tab
Article in Spanish | LILACS | ID: biblio-970392

ABSTRACT

Introducción. La bacteriemia por Pseudomonas aeruginosa (PAE) en niños es infrecuente. Objetivo.Describir las características epidemiológicas, clínicas, microbiológicas y evolutivas en niños con bacteriemia por PAE. Métodos. Estudio de cohorte retrospectivo. Resultados. Se incluyeron 100 pacientes (p). La mediana de edad fue de 27 meses (RIC 6-88).Tenían enfermedad de base: 93 p (93%) y 36 de ellos estaban neutropénicos. Ochenta y cinco p (85%) habían recibido antibióticos en el último mes, 60 (60%) tuvieron procedimientos invasivos previos y 81 (81%) tuvieron internaciones previas. Ingresaron con shock séptico 42 p (42%), 56 p (56%) fueron admitidos en unidad de cuidados intensivos (UCI) y 49 (49%) requirieron ventilación mecánica (VM). La bacteriemia fue primaria en 17 p (17%); asociada a catéter en 15 p (15%) y secundaria en 68 p (68%). El foco más frecuente fue mucocutáneo, 21 p, seguido por el pulmonar, 20 p. El tratamiento empírico fue adecuado en 84 p (84%). La resistencia a uno o más grupos de antibióticos se dio en el 38% de los casos, 11% fueron multirresistentes y 15% fueron resistentes sólo a carbapenemes. Fallecieron 31 p (31%). Pseudomonas aeruginosa resistente a carbapenemes en forma exclusiva o combinada con otros antibióticos se relacionó en esta serie a exposición previa a antibióticos, (p≤0,03), tratamiento empírico inicial inadecuado (p≤0,006) y mayor mortalidad (p≤0,01), prolongación de la internación y del tiempo de tratamiento (p≤0,001)


Introduction. Pseudomonas aeruginosa (PAE) associated bacteremia is uncommon in children. Objective. To describe the epidemiological, clinical, and microbiological features and outcome in children with PAE-associated bacteremia. Methods. A retrospective cohort study. Results. 100 patients (p) were included. Median age was 27 months (IQR 6-88). Overall 93 p (93%) had an underlying disease, 36 of whom had neutropenia. Eighty-five p (85%) had received antibiotics over the previous month, 60 (60%) had undergone previous invasive procedures, and 81 (81%) had been previously admitted. Forty-two p (42%) were admitted because of septic shock, 56 p (56%) were admitted to the intensive care unit (ICU), and 49 (49%) required mechanical ventilation (MV). Seventeen p (17%) had primary bacteremia, 15 p (15%) had catheter-related bacteremia, and 68 p (68%) had secondary bacteremia. The most common focus was mucocutaneous (21 p), followed by pulmonary (20 p). Emperical treatment was adequate in 84 p (84%). Resistance to one or more groups of antibiotics was observed in 38% of the cases; 11% were multiresistant and 15% were only resistant to carbapenems. Thirty-one p (31%) died. In our series, Pseudomonas aeruginosa resistant to carbapenems only or combined with other antibiotics was associated with previous exposition to antibiotics (p≤0.03), inadequate initial emperical treatment (p≤0.006), and higher mortality (p≤0.01), and longer hospital stay and treatment duration (p≤0.001)


Subject(s)
Humans , Infant , Child, Preschool , Child , Adolescent , Pseudomonas aeruginosa/isolation & purification , Pseudomonas aeruginosa/drug effects , Pseudomonas Infections/diagnosis , Pseudomonas Infections/microbiology , Pseudomonas Infections/epidemiology , Bacteremia/microbiology , Bacteremia/mortality , Drug Resistance, Multiple, Bacterial/drug effects , Carbapenems/pharmacology , Prospective Studies , Cohort Studies , Anti-Bacterial Agents/pharmacology
12.
West Indian med. j ; 67(4): 344-349, Oct.-Dec. 2018. tab
Article in English | LILACS | ID: biblio-1045862

ABSTRACT

ABSTRACT Objective: To determine the role of extended-spectrum β-lactamases in carbapenem-resistant Gram-negative bacteria from south-western Nigeria. Methods: Twenty-seven carbapenem-resistant isolates that were found to be non-carbapenemase producers (15 Escherichia coli, 9 Klebsiella pneumoniae and 3 Pseudomonas aeruginosa) were further studied. These isolates were subjected to analysis including phenotypic and genotypic detection of various β-lactamases, efflux activity, outer membrane protein, plasmids replicon typing, detection of transferable genes and resistances and typing using random amplified polymorphic DNA tests. Results: No isolates demonstrated de-repression of efflux, but all showed either complete loss or reduced production of outer membrane proteins. Transconjugants from these strains contained various genes including plasmid-mediated quinolone resistance and extended-spectrum beta-lactamases. All the transconjugants carried the blaCTX-M-15 gene. The transconjugants had varying minimum inhibitory concentrations of carbapenems ranging from 0.03 μg/ml to 8 μg/ml. Varying resistances to other antimicrobial agents were also transferred with the plasmids. The donor isolates were not clonally related by molecular typing. Conclusion: Resistance to carbapenem antibiotics in this sample was not mediated only by carbapenemases but also by production of extended-spectrum β-lactamases (largely CTX-M-15), accompanied by protein loss. This was an important mechanism underpinning carbapenem resistance in these clinical isolates of various species.


RESUMEN Objetivo: Determinar el papel de las betalactamasas de espectro extendido en la resistencia al carbapenem en las bacterias gramnegativas en Nigeria. Métodos: Veintisiete aislados resistentes al carbapenem que fueron hallados productores de no carbapenemasas (15 Escherichia coli, 9 Klebsiella pneumoniae, y 3 Pseudomonas aeruginosa) fueron estudiados con mayor profundidad. Estos aislados fueron sometidos a análisis incluyendo la detección fenotípica y genotípica de varias betalactamasas, la actividad de eflujo, las porinas de la membrana externa, la tipificación del replicón plasmídico, la detección de genes transferibles y resistencias y tipificación usando pruebas de ADN polimórficas amplificadas aleatorias. Resultados: Ninguno de los aislamientos mostró desrepresión de eflujo, pero todos demostraron la pérdida completa o la producción reducida de porinas externas de la membrana. Los transconjugantes de estas cepas contenían varios genes incluyendo resistencia a la quinolona mediada por plásmidos y betalactamasas de espectro extendido. Todos los transconjugantes portaban el gen blaCTX-M-15. Los transconjugantes tenían diversas concentraciones inhibitorias mínimas de carbapenemas que oscilaban entre 0.03 μg/ml y 8 μg/ml. Varias resistencias a otros agentes antimicrobianos fueron también transferidas con los plásmidos. Los aislamientos del donante no estuvieron relacionados clonalmente por tipificación molecular. Conclusión: La resistencia al antibiótico carbapenem en esta muestra no fue mediada solamente por las carbapenemasas, sino también por la producción de betalactamasas de espectro extendido (en gran parte CTX-M-15), acompañado por pérdida de porina. Éste era un mecanismo importante que sustentaba la resistencia al carbapenem en estos aislados clínicos de varias especies.


Subject(s)
Humans , Pseudomonas aeruginosa/drug effects , beta-Lactamases/biosynthesis , Escherichia coli/drug effects , Klebsiella pneumoniae/drug effects , Anti-Bacterial Agents/pharmacology , Phenotype , Pseudomonas aeruginosa/enzymology , Drug Resistance, Microbial , Microbial Sensitivity Tests , Escherichia coli/enzymology , Genotype , Klebsiella pneumoniae/enzymology , Nigeria
13.
Rev. Soc. Bras. Med. Trop ; 51(5): 610-615, Sept.-Oct. 2018. tab, graf
Article in English | LILACS | ID: biblio-957455

ABSTRACT

Abstract INTRODUCTION: Health care-associated infections caused by metallo-β-lactamase (MBL)-producing Pseudomonas aeruginosa are a significant growing concern in patients with burns worldwide. The aims of this study were to determine the antibiotic susceptibility of and detect the presence of MBLs among P. aeruginosa isolates and assess their clonal relationship using enterobacterial repetitive intergenic consensus (ERIC)-PCR. METHODS: Non-duplicated clinical isolates (160) of P. aeruginosa were collected from patients with burns at the Motahari Hospital in Tehran, Iran. All isolates were identified using standard laboratory methods and further characterized for antimicrobial susceptibility. Any carbapenem-resistant isolates were then examined for MBL production by the E-test and MBL-encoding genes were detected by PCR. The clonal relatedness of MBL-producing isolates was assessed by ERIC-PCR. RESULTS: For multidrug-resistant isolates, the highest rates of susceptibility were observed for colistin 160 (100%), polymyxin B 160 (100%), and ceftazidime 32 (20%). In total, 69 (43.7%) isolates were identified as MBL producers. Twenty-eight (17.5%) isolates were positive for the bla VIM-1 gene followed by the bla IMP-1 (15.6%) and bla SPM-1 (5.6%) genes. ERIC-PCR revealed three separate genotypes, where type A (76.8%) was the most prevalent, followed by B (20.3%), and then C (2.9%). CONCLUSIONS: Our present study found that the bla IMP-1 and bla VIM-1 genes were present at a significant frequency and also detected the bla SPM-1 gene in P. aeruginosa isolates for the first time, highlighting the need for establishing suitable infection control measures to successfully treat patients and prevent further spread of these resistant organisms among patients with burns.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Aged , Young Adult , Pseudomonas aeruginosa/drug effects , Pseudomonas Infections/microbiology , beta-Lactamases/metabolism , Burns/microbiology , Anti-Bacterial Agents/pharmacology , Phenotype , Pseudomonas aeruginosa/enzymology , Microbial Sensitivity Tests , Cross-Sectional Studies , Drug Resistance, Multiple, Bacterial , Middle Aged
14.
Rev. Soc. Bras. Med. Trop ; 51(3): 270-276, Apr.-June 2018. tab, graf
Article in English | LILACS | ID: biblio-957426

ABSTRACT

Abstract Carbapenem-resistant Pseudomonas aeruginosa (CRPA) has been considered a major cause of infection and mortality in burn patients, especially in developing countries such as Iran. One of the most common mechanisms of carbapenem resistance is production of metallo-β-lactamases [(MBLs), including Verona Integron-encoded Metallo-beta-lactamase (VIM), imipenemase (IMP), São Paulo metalo-beta-lactamase (SPM), German imipenemase (GIM), New Delhi metallo-beta-lactamase (NDM), Dutch imipenemase (DIM), Adelaide imipenemase (AIM), Seoul imipenemase (SIM), KHM, Serratia metallo-β-lactamase (SMB), Tripoli metallo-β-lactamase (TMB), and Florence imipenemase (FIM)]. Limited information is available on the prevalence of CRPA and MBLs in Iranian burn units. We performed a systematic search by using different electronic databases, including Medline (via PubMed), Embase, Web of Science, and Iranian Database. Of 586 articles published from January 2000 to December 2016, 14 studies reporting the incidence of CRPA and MBLs as detected by molecular methods in burn patients were included in this review. The meta-analyses showed that the prevalence of CRPA, IMP, and VIM was 76.8% (95% CI 67.5-84.1), 13.1% (95% CI 4.7-31.5), and 21.4% (95% CI 14.6-30.1), respectively, in Iranian burn centers and remaining MBLs types have not yet been detected. There was a high prevalence of MBLs and CRPA in Iranian burn centers. Therefore, these measurements should be applied nationally and rigorous infection control measures and antimicrobial stewardship will be the major pillars to control multidrug resistant microorganisms, such as CRPA.


Subject(s)
Humans , Pseudomonas aeruginosa/genetics , Pseudomonas Infections/microbiology , Carbapenems , beta-Lactam Resistance/genetics , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/enzymology , Pseudomonas Infections/epidemiology , DNA, Bacterial/genetics , Microbial Sensitivity Tests , Prevalence , Iran
15.
West Indian med. j ; 67(2): 105-109, Apr.-June 2018. tab, graf
Article in English | LILACS | ID: biblio-1045828

ABSTRACT

ABSTRACT Objective: Several mechanisms account for carbapenem resistance in Pseudomonas (P) aeruginosa which is an emerging problem at a tertiary care hospital (TCH) in Jamaica. The observed pattern of carbapenem resistance that results from efflux mechanisms is unique because it is specific to meropenem (MEM). An investigation of efflux as a mechanism of carbapenem resistance was needed as the information obtained could inform therapeutic and infection control strategies. Methods: At the Microbiology Laboratory of a TCH in Jamaica, from May 2009 to March 2011, of 105 multidrug-resistant Gram-negative bacilli isolated from clinical specimens submitted for routine identification and susceptibility testing, all the MEM-resistant P aeruginosa isolates (a total of 10) were selected. They were tested for efflux using the efflux inhibitor phenylalanine-arginine-β-naphthylamide (PAβN) in a method described by Giske et al in 2008. Results: This study detected evidence of MEM efflux in 80% of MEM-resistant P aeruginosa implicated in nosocomial infections at this TCH in Jamaica, using the PAβN inhibition assay. Meropenem-efflux-positive isolates belonged to two unrelated chromosomal lineages. Conclusion: These results underscored the need for improved surveillance and control to prevent this mechanism from emerging in further P aeruginosa strains.


RESUMEN Objetivo: Varios mecanismos explican la resistencia al carbapenem en Pseudomonas (P) Aeruginosa - un problema que recientemente se está presentando en un hospital de atención terciaria (HAT) en Jamaica. El patrón observado de resistencia al carbapenem que resulta de los mecanismos de eflujo es único, porque es específico del meropenem (MEM). Fue necesario realizar una investigación del eflujo como mecanismo de resistencia al carbapenem, ya que la información obtenida podría usarse para las estrategias de terapia y de control de la infección. Métodos: En el Laboratorio de Microbiología de un HAT en Jamaica, de mayo de 2009 a marzo de 2011, de 105 bacilos gram-negativos polifármacorresistentes aislados de especímenes clínicos presentados para identificación de rutina y pruebas de susceptibilidad, se seleccionaron todos los aislados de P aeruginosa (un total de 10) resistentes a MEM. Estos aislados fueron sometidos a prueba de detección de eflujo, usando el inhibidor de eflujo de fenilalanina-arginina-β-naftilamida (PAβN) en un método descrito por Giske et al en 2008. Resultados: Este estudio detectó evidencia de eflujo de MEM en el 80% de P aeruginosa resistente a MEM implicado en infecciones nosocomiales en este HAT de Jamaica, usando el ensayo de inhibición PAβN. Los aislados positivos al eflujo de meropenem pertenecían a dos linajes cromosómicos no relacionados. Conclusión: Estos resultados subrayaron la necesidad de mejorar la vigilancia y el control para prevenir que este mecanismo vuelva a producirse en nuevas cepas de P aeruginosa.


Subject(s)
Humans , Pseudomonas aeruginosa/drug effects , Drug Resistance, Bacterial , Meropenem/pharmacology , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests , Electrophoresis, Gel, Pulsed-Field , Genes, MDR
17.
Braz. j. infect. dis ; 22(2): 129-136, Mar.-Apr. 2018. tab, graf
Article in English | LILACS | ID: biblio-951633

ABSTRACT

ABSTRACT Introduction: Biofilm production is an important mechanism for the survival of Pseudomonas aeruginosa and its relationship with antimicrobial resistance represents a challenge for patient therapeutics. P. aeruginosa is an opportunistic pathogen frequently associated to nosocomial infections, especially in imunocompromised hosts. Objectives: Analyze the phenotypic biofilm production in P. aeruginosa isolates, describe clonal profiles, and analyze quorum sensing (QS) genes and the occurrence of mutations in the LasR protein of non-biofilm producing isolates. Methods: Isolates were tested for biofilm production by measuring cells adherence to the microtiter plates. Clonal profile analysis was carried out through ERIC-PCR, QS genes were by specific PCR. Results: The results showed that 77.5% of the isolates were considered biofilm producers. The results of genotyping showed 38 distinct genetic profiles. As for the occurrence of the genes, 100% of the isolates presented the lasR, rhlI and rhlR genes, and 97.5%, presented the lasI gene. In this study nine isolates were not biofilm producers. However, all presented the QS genes. Amplicons related to genes were sequenced in three of the nine non-biofilm-producing isolates (all presenting different genetic similarity profile) and aligned to the sequences of those genes in P. aeruginosa strain PAO1 (standard biofilm-producing strain). Alignment analysis showed an insertion of three nucleotides (T, C and G) causing the addition of an amino acid valine in the sequence of the LasR protein, in position 53. Conclusion: The modeling of the resulting LasR protein showed a conformational change in its structure, suggesting that this might be the reason why these isolates are unable to produce biofilm.


Subject(s)
Humans , Pseudomonas aeruginosa/physiology , Pseudomonas Infections/microbiology , Bacterial Proteins/genetics , Trans-Activators/genetics , Biofilms/growth & development , Biofilms/drug effects , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/chemistry , Pseudomonas Infections/drug therapy , Bacterial Proteins/chemistry , Trans-Activators/chemistry , Polymerase Chain Reaction/methods , Cross Infection , Drug Resistance, Multiple, Bacterial , Anti-Infective Agents/pharmacology , Anti-Bacterial Agents/pharmacology
18.
Electron. j. biotechnol ; 32: 41-46, Mar. 2018. tab, ilus, graf
Article in English | LILACS | ID: biblio-1022633

ABSTRACT

Background: In view of the current low efficacy of bacterial infection treatment the common trend towards searching for antibiotic systems exhibiting synergistic action is well justified. Among carbapenem analogues a particularly interesting option is provided by combinations of clavulanic acid with meropenem, which have proven to be especially effective. Results: Determination of the minimal inhibitory concentration (MIC) along with the method based on flow cytometry constitutes an important tool in the identification of bacterial sensitivity to active substances. Within this study the inhibitory effect of doripenem, clavulanic acid and the doripenem-clavulanate acid system was analyzed in relation to such bacteria as Salmonella enteritidis, Salmonella typhimurium, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Clostridium butyricum and Clostridium pasteurianum, Acinetobacter baumannii, Enterobacter aerogenes. The lowest MIC, amounting to 0.03 µg/mL, was observed for the doripenem-clavulanate acid system in the case of E. coli ATCC 25922. In turn, the lowest MIC for doripenem applied alone was recorded for K. pneumoniae ATCC 31488, for which it was 0.1 µg/mL. The strain which proved to be most resistant both to doripenem and the doripenem-clavulanate acid system, was A. baumannii, with MIC of 32 µg/mL (clinical isolate) and 16 µg/mL (reference strain). Cytometric analysis for P. aeruginosa ATCC 27853 and S. aureus ATCC 25923 showed changes in cells following exposure to limiting concentrations of the active substance. Conclusions: Analysis of MIC supplies important information concerning microbial sensitivity to active substances, mainly in terms of limiting concentrations causing mortality or vitality of the tested species, which is essential when selecting appropriate antibiotic therapy.


Subject(s)
Bacteria/drug effects , Clavulanic Acids/pharmacology , /pharmacology , Anti-Bacterial Agents/pharmacology , Pseudomonas aeruginosa/drug effects , Salmonella/drug effects , Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Clostridium/drug effects , Drug Interactions , Flow Cytometry , Klebsiella pneumoniae/drug effects
19.
Rev. bras. anestesiol ; 68(1): 69-74, Jan.-Feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-897807

ABSTRACT

Abstract Introduction Propofol and Ephedrine are commonly used during anesthesia maintenance, the former as a hypnotic agent and the later as a vasopressor. The addition of propofol to ephedrine or administration of ephedrine before propofol injection is useful for decreasing or preventing propofol related hemodynamic changes and vascular pain. This in vitro study evaluated the antibacterial effect on common hospital-acquired infection pathogens of ephedrine alone or combined with propofol. Material and method The study was performed in two stages. In the first, the Minimum Inhibitory Concentration of propofol and ephedrine alone and combined was calculated for Escherichia coli, Enterococcus faecium, Staphylococcus aureus, Pseudomonas aeruginosa, and a clinical isolate of Acinetobacter spp. at 0, 6, 12 and 24 h, using the microdilution method. In the second stage, the same drugs and combination were used to determine their effect on bacterial growth. Bacterial solutions were prepared at 0.5 MacFarland in sterile 0.9% physiological saline and diluted at 1/100 concentration. Colony numbers were measured as colony forming units.mL-1 at 0, 2, 4, 6, 8, 10 and 12th hours. Results Ephedrine either alone or combined with propofol did not have an antimicrobial effect on Escherichia coli, Enterococcus faecium, or Pseudomonas aeruginosa and this was similar to propofol. However, ephedrine alone and combined with propofol was found to have an antimicrobial effect on Staphylococcus aureus and Acinetobacter species at 512 mcg.mL-1 concentration and significantly decreased bacterial growth rate. Conclusion Ephedrine has an antimicrobial activity on Staphylococcus aureus and Acinetobacter species which were frequently encountered pathogens as a cause of nosocomial infections.


Resumo Introdução Propofol e efedrina são fármacos comumente usados durante a manutenção da anestesia, o primeiro como agente hipnótico e o segundo como vasopressor. A adição de propofol à efedrina ou a administração de efedrina antes da injeção de propofol é útil para diminuir ou prevenir alterações hemodinâmicas e dor vascular relacionadas ao propofol. Este estudo in vitro avaliou o efeito antibacteriano de efedrina, isolada ou em combinação com propofol, em patógenos comuns implicados em infecção hospitalar. Material e método O estudo foi feito em duas etapas. Na primeira, a concentração inibitória mínima (CIM) de propofol e de efedrina isolada e em combinação foi calculada para Escherichia coli, Enterococcus faecium, Staphylococcus aureus, Pseudomonas aeruginosa e um isolado clínico de Acinetobacter spp às 0, 6, 12 e 24 horas, com o método de microdiluição. Na segunda etapa, o mesmo fármaco e sua combinação foram usados para determinar seus efeitos no crescimento bacteriano. As soluções bacterianas foram preparadas em soro fisiológico a 0,9% em 0,5 McFarland e diluídas a uma concentração de 1/100. Os números das colônias foram medidos como ufc.mL-1 às 0, 2, 4, 6, 8, 10 e 12 horas. Resultados Efedrina isolada ou em combinação com propofol não apresentou efeito antimicrobiano sobre E. coli, E. faecium ou P. aeruginosa, um resultado semelhante ao de propofol. Porém, efedrina isolada e em combinação com propofol apresentou efeito antimicrobiano sobre Staphylococcus aureus e Acinetobacter spp, em concentração de 512 mcg.mL-1, e redução significativa da taxa de crescimento bacteriano. Conclusão Efedrina tem atividade antimicrobiana em S. aureus e Acinetobacter spp, patógenos frequentemente identificados como causa de infecções nosocomiais.


Subject(s)
Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Vasoconstrictor Agents/pharmacology , Acinetobacter/drug effects , Propofol/pharmacology , Enterococcus faecium/drug effects , Ephedrine/pharmacology , Hypnotics and Sedatives/pharmacology , Vasoconstrictor Agents/administration & dosage , Microbial Sensitivity Tests , Propofol/administration & dosage , Ephedrine/administration & dosage , Escherichia coli/drug effects , Hypnotics and Sedatives/administration & dosage , Anti-Bacterial Agents
20.
Rev. chil. cir ; 70(1): 13-18, 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-899650

ABSTRACT

Resumen Introducción La resistencia a antibióticos es un problema mundial. En los pacientes que requieren cirugía de urgencia, los antibióticos son un apoyo importante concomitante al acto quirúrgico. Objetivo Analizar los cultivos de líquido peritoneal obtenidos de pacientes operados por patología quirúrgica abdominal de urgencia. Materiales y Métodos Se realiza una cohorte prospectiva de los pacientes operados de urgencia. Se tomó cultivo de líquido peritoneal y se procesó según técnica estandarizada. Resultados Se encontró un 39,4% de cultivos positivos. E. coli fue el germen más frecuente. Destacan 5 cultivos positivos para P. aeruginosa. Existe un 25% de resistencia a ampicilina/sulbactam y 19% a quinolonas para E. coli. Conclusión La resistencia encontrada fue menor a lo reportado en la literatura, pero aún destacable. El conocimiento del perfil de bacterias y sus resistencias a antimicrobianos son importantes para las políticas hospitalarias locales de uso racional de antibióticos.


Background Antimicrobial resistance is a worldwide problem. In patients requiring emergency surgery, antibiotics are an important assistance additional to surgical intervention. Objective Analize peritoneal fluid cultures obtaines from patients who underwent emergency surgery. Methods A prospective cohort of emergency abdominal surgical patients were enrolled. Peritoneal fluid cultures were taken and processed according to standarized technique. Results A 39.4% of positive cultures was found. E. coli was the most common bacteria identified. Five positive cultures for P. aeruginosa stand out. E. coli had 25% resistance to ampicillin/sulbactam and 19% for quinolones. Conclusion Resistance found was lower than international reports, but still noteworthy. Knowledge of local bacteria profile and antimicrobial resistance is important for local antibiotic hospital policy.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Bacteria/drug effects , Ascitic Fluid/microbiology , Abdomen/surgery , Anti-Bacterial Agents/pharmacology , Pseudomonas aeruginosa/drug effects , Bacteria/isolation & purification , Microbial Sensitivity Tests , Drug Resistance, Bacterial , Emergencies , Escherichia coli/drug effects , Klebsiella pneumoniae/drug effects
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