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Rev. pediatr. electrón ; 16(2): 3-7, ago. 2019.
Article in Spanish | LILACS | ID: biblio-1021327


Los pacientes inmunocomprometidos presentan un riesgo aumentado de colonización e infecciones por microorganismos multirresistentes (MOR), entre ellos Enterococcus spp resistentes a vancomicina (ERV) y bacterias productoras de betalactamasas de espectro extendido (BLEE), las cuales son causa importante de morbimortalidad. OBJETIVO: Describir la prevalencia de MOR en Servicio de Oncología del Hospital Roberto del Río. MÉTODO: Se realizó un estudio descriptivo retrospectivo de los niños hospitalizados en el servicio de oncología desde enero a diciembre del 2016 a los cuales se les realizó vigilancia de portación de ERV y BLEE. RESULTADOS: De los 97 pacientes hospitalizados, se identificó un 8% de portación de ERV, un 13,7% de BLEE y un 6,8% presentó portación de ambos microorganismos. DISCUSIÓN: Entre enero 2012 a diciembre del 2013 se observó en nuestro centro que un 52% de los pacientes hospitalizados en oncología estaban colonizados por ERV, la disminución significativa de la portación podría deberse a la mejor adherencia de normas de prevención de infecciones asociadas a la atención en salud (IAAS), programa de uso racional de antimicrobianos y a la nueva infraestructura del servicio.

The inmunosupressed patients are at increased risk of colonization and infection with vancomycin resistant Enterococci (VRE) and extended- spectrum b-lactamase producing Enterobacteriaceae (ESBL), which can cause substantial morbidity and mortality. OBJECTIVE: Describe the prevalence of VRE and ESBL in the Oncology Unit of Roberto del Río Hospital. METHODS: Descriptive and retrospective study of hospitalized children since January to December 2016 in the Oncology Unit, that underwent VRE and ESBL colonization surveillance. RESULTS: From the 97 hospitalized patients, there were 8% of VRE colonization, 13.7% of ESBL and 6.8% of colonization from both microorganism. DISCUSSION: Between January 2012 and December 2013, we observed that 52% of hospitalized patients in the Oncology Unit were colonized by VRE. The significant decrease in colonization may be due to better fulfillment of healthcare-associated infections (HAI) normative, antibiotics stewardship and new infraestructure of our unit.

Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , beta-Lactamases/metabolism , Cross Infection/epidemiology , Gram-Positive Bacterial Infections/epidemiology , Vancomycin-Resistant Enterococci/enzymology , Cross Infection/microbiology , Cross Infection/prevention & control , Prevalence , Retrospective Studies , Oncology Service, Hospital , Infection Control , Gram-Positive Bacterial Infections/microbiology , Gram-Positive Bacterial Infections/prevention & control , Hospitals, Pediatric
Rev. bras. enferm ; 72(3): 760-766, May.-Jun. 2019. tab
Article in English | LILACS, BDENF | ID: biblio-1013564


ABSTRACT Objective: To evaluate the risk factors related to Klebsiella pneumoniae carbapenemase infection after renal transplantation. Methods: This was a retrospective epidemiological (case-control) study, conducted from October 2011 to march 2016. Transplanted patients with infection by this bacteria during hospitalization were selected as cases. The controls were paired by age, sex, type of donor and transplant time. The proportion of cases and controls was 1:2. Results: Thirty hundred and five patients were included in the study (45 cases and 90 controls). The risk factors found for infection by KPC were: time of hospitalization after the transplant (OR: 4.82; CI95% 2.46-9.44), delayed kidney function (OR: 5.60; CI95% 1.91-11.01) and previous infectious for another microorganism ( OR: 34.13 CI95% 3.52-132.00). Conclusion: The risk of acquisition of this bacterium was directly related to invasive procedures and exposure to the hospital environment. The findings reinforce the importance of prevention measures and control of infection by this microorganism.

RESUMEN Objetivo: Evaluar los factores de riesgo relacionados con la infección por Klebsiella pneumoniae carbapenemasa después del trasplante renal. Método: Estudio retrospectivo epidemiológico (caso-control), realizado de octubre de 2011 a marzo de 2016. Pacientes transplantados con infección por esa bacteria durante la internación fueron seleccionados como casos. Los controles se parearon por edad, sexo, tipo de donante y tiempo de trasplante. La proporción de casos y controles fue de 1: 2. Resultados: Treinta y cinco pacientes fueron incluidos en el estudio (45 casos y 90 controles). Los factores de riesgo para la infección encontrados por KPC fueron: tiempo de hospitalización después del trasplante (OR: 4,82, IC95% 2,46-9,44), función renal retardada (OR: 5,60, IC95% 1, 91-11,01) y anterior infecciosa para otro microorganismo (OR: 34,13 IC95% 3,52-132,00). Conclusión: El riesgo de adquisición de esta bacteria estuvo directamente relacionado a procedimientos invasivos y exposición al ambiente hospitalario. Los hallazgos refuerzan la importancia de medidas de prevención y control de la infección por ese microorganismo.

Humans , Male , Female , Adult , Pneumonia/ethnology , Bacterial Proteins/adverse effects , beta-Lactamases/adverse effects , Klebsiella Infections/etiology , Kidney Transplantation/adverse effects , Pneumonia/chemically induced , Pneumonia/epidemiology , Bacterial Proteins/metabolism , beta-Lactamases/metabolism , Brazil/epidemiology , Klebsiella Infections/metabolism , Klebsiella Infections/epidemiology , Case-Control Studies , Retrospective Studies , Risk Factors , Kidney Transplantation/methods , Klebsiella pneumoniae/metabolism , Klebsiella pneumoniae/pathogenicity , Middle Aged
Braz. j. microbiol ; 49(4): 914-918, Oct.-Dec. 2018. tab
Article in English | LILACS | ID: biblio-974286


ABSTRACT The global emergence of carbapenemases led to the need of developing new methods for their rapid detection. The aim of this study was to evaluate the performance of the rapid tests for carbapenemase-producing and non-producing Enterobacteriaceae. Carbapenem non-susceptible Enterobacteriaceae from a surveillance study submitted to a multiplex real time PCR for carbapenemase detection were included in this study. The isolates were subjected to the rapid phenotypic tests Carba NP, Blue-Carba and Carbapenem Inactivation Method (CIM). A total of 83 carbapenemase-producing (43) and non-producing (40) isolates were included in the study. The sensitivity/specificity were 62.7%/97.5%, 95.3%/100%, and 74.4%/97.5% for Carba NP, Blue-Carba and CIM, respectively. Both Carba NP and Blue-Carba presented their final results after 75 min of incubation; the final results for CIM were obtained only after 8 h. Failure to detect OXA-370 carbapenemase was the main problem for Carba NP and CIM assays. As the Blue-Carba presented the highest sensitivity, it can be considered the best screening test. Conversely, CIM might be the easiest to perform, as it does not require special reagents. The early detection of carbapenemases aids to establish infection control measures and prevent carbapenemases to spread reducing the risk of healthcare associated infections and therapeutic failure.

Humans , Bacterial Proteins/analysis , beta-Lactamases/analysis , Enterobacteriaceae/enzymology , Enterobacteriaceae Infections/microbiology , Enzyme Assays/methods , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , beta-Lactamases/genetics , beta-Lactamases/metabolism , Brazil , Carbapenems/pharmacology , Polymerase Chain Reaction , Sensitivity and Specificity , Enterobacteriaceae/isolation & purification , Enterobacteriaceae/drug effects , Enterobacteriaceae/genetics , Enterobacteriaceae Infections/diagnosis , Anti-Bacterial Agents/pharmacology
Braz. j. microbiol ; 49(4): 885-890, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-974312


ABSTRACT In this study, the performance of the "RESIST-3 O.K.N. K-SeT" (Coris BioConcept, Gembloux, Belgium) immunochromatographic assay was evaluated in 132 Klebsiella pneumoniae comprising 102 carbapenem resistant and 30 carbapenem susceptible isolates. Genotypically known isolates of Gram negative bacteria (n = 22) including various species were also tested by the assay as controls. The isolates tested by the immunochromatographic assay and also were run PCR for bla KPC, bla IMP, bla VIM, bla NDM, and bla OXA-48. The rates of bla NDM, bla OXA-48, and bla KPC in carbapenem resistant isolates were found at 52.9%, 39.2%, and 2.0%, respectively. Both bla NDM and bla OXA-48 were found in six (5.9%) isolates. The results of the assay showed 100% concordance with those obtained by PCR in 132 K. pneumoniae. The agreement between the two methods was found to be identical at the isolate level. The assay also correctly detected all genotypically known isolates of Escherichia coli, Serratia marcescens, Citrobacter freundii, Enterobacter cloacae, K. pneumoniae carrying bla KPC, bla NDM, and/or bla OXA-48. On the other hand, the assay did not exhibit any cross-reaction in control isolates harboring bla IMP and bla VIM. We conclude that the RESIST-3 O.K.N. K-SeT is a reliable, rapid, and user friendly test and we recommend it for routine diagnostic laboratories.

Humans , Bacterial Proteins/analysis , beta-Lactamases/analysis , Klebsiella Infections/microbiology , Immunoassay/methods , Klebsiella pneumoniae/enzymology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Turkey , beta-Lactamases/metabolism , Carbapenems/pharmacology , Polymerase Chain Reaction , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/chemistry , Anti-Bacterial Agents/pharmacology
Rev. Soc. Bras. Med. Trop ; 51(5): 610-615, Sept.-Oct. 2018. tab, graf
Article in English | LILACS | ID: biblio-957455


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.

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
Braz. j. microbiol ; 49(3): 569-574, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951794


Abstract Multidrug-resistant microorganisms are of great concern to public health. Genetic mobile elements, such as plasmids, are among the most relevant mechanisms by which bacteria achieve this resistance. We obtained an Escherichia coli strain CM6, isolated from cattle presenting severe diarrheic symptoms in the State of Querétaro, Mexico. It was found to contain a 70 kb plasmid (pMEX01) with a high similarity to the pHK01-like plasmids that were previously identified and described in Hong Kong. Analysis of the pMEX01 sequence revealed the presence of a blaCTX-M-14 gene, which is responsible for conferring resistance to multiple β-lactam antibiotics. Several genes putatively involved in the conjugative transfer were also identified on the plasmid. The strain CM6 is of high epidemiological concern because it not only displays resistance to multiple β-lactam antibiotics but also to other kinds of antibiotics.

Animals , Cattle , Plasmids/genetics , Cattle Diseases/microbiology , Drug Resistance, Bacterial , beta-Lactams/pharmacology , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli Infections/veterinary , Anti-Bacterial Agents/pharmacology , Plasmids/metabolism , beta-Lactamases/genetics , beta-Lactamases/metabolism , Microbial Sensitivity Tests , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Escherichia coli/metabolism , Escherichia coli Infections/microbiology , Mexico
Braz. j. microbiol ; 49(3): 471-480, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951821


Abstract Escalating burden of antibiotic resistance that has reached new heights present a grave concern to mankind. As the problem is no longer confined to clinics, we hereby report identification of a pandrug resistant Escherichia coli isolate from heavily polluted Delhi stretch of river Yamuna, India. E. coli MRC11 was found sensitive only to tobramycin against 21 antibiotics tested, with minimum inhibitory concentration values >256 µg/mL for amoxicillin, carbenicillin, aztreonam, ceftazidime and cefotaxime. Addition of certain heavy metals at higher concentrations were ineffective in increasing susceptibility of E. coli MRC11 to antibiotics. Withstanding sub-optimal concentration of cefotaxime (10 µg/mL) and mercuric chloride (2 µg/mL), and also resistance to their combinatorial use, indicates better adaptability in heavily polluted environment through clustering and expression of resistance genes. Interestingly, E. coli MRC11 harbours two different variants of blaTEM (blaTEM-116 and blaTEM-1 with and without extended-spectrum activity, respectively), in addition to mer operon (merB, merP and merT) genes. Studies employing conjugation, confirmed localization of blaTEM-116, merP and merT genes on the conjugative plasmid. Understanding potentialities of such isolates will help in determining risk factors attributing pandrug resistance and strengthening strategic development of new and effective antimicrobial agents.

Metals, Heavy/pharmacology , Drug Resistance, Multiple, Bacterial , Rivers/microbiology , Escherichia coli/drug effects , Anti-Bacterial Agents/pharmacology , Operon , beta-Lactamases/genetics , beta-Lactamases/metabolism , Microbial Sensitivity Tests , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Escherichia coli/isolation & purification , Escherichia coli/enzymology , Escherichia coli/genetics , India
Braz. j. infect. dis ; 22(1): 47-50, Jan.-feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-1039209


ABSTRACT Carbapenemases have great importance in the global epidemiological scenario since infections with carbapenemase-producing bacteria are associated with high mortality, especially in hospitalized patients in intensive care units. This study describes two microorganisms producers of the New Delhi Metallo-b-lactamase, Klebsiella pneumoniae and Citrobacter freundii, from two patients admitted to a public hospital in Salvador, Bahia. These are the first clinical cases of New Delhi Metallo-b-lactamase described in microorganisms in the north and northeast Brazil. The isolates were characterized by antimicrobial susceptibility test, with resistance to all β-lactams including carbapenems, negative Modified Hodge Test and the synergy test with Ethylenediaminetetraacetic acid, Phenylboronic Acid and Cloxacillin was positive only with Ethylenediaminetetraacetic acid (difference of >5 mm in the inhibition zone between the disk without and with the inhibitor). Analysis by multiplex PCR for blaIMP, blaVIM, blaNDM, blaKPC and blaOXA-48 enzymes confirmed the presence of blaNDM gene. This report of two different New Delhi Metallo-b-lactamase-producing microorganisms in a different region of Brazil confirms the risk of spreading resistance genes between different species and emphasizes the need for prevention and control of infections caused by these pathogens, which have limited treatment options and have been linked to high mortality rates.

Humans , Male , Adult , Aged , Bacterial Proteins/metabolism , beta-Lactamases/metabolism , Enterobacteriaceae/enzymology , Enterobacteriaceae Infections/microbiology , Bacterial Proteins/drug effects , beta-Lactamases/drug effects , Brazil , Carbapenems/pharmacology , Fatal Outcome , Drug Resistance, Bacterial , Enterobacteriaceae/isolation & purification , Enterobacteriaceae/drug effects , Multiplex Polymerase Chain Reaction , Hospitals, Public
Medwave ; 18(2): e7191, 2018.
Article in English, Spanish | LILACS | ID: biblio-912086


Las carbapenemasas son uno de los mecanismos enzimáticos de resistencia antimicrobiana, que compromete la mayor parte de los antibióticos betalactámicos. Por lo general, su producción se debe al uso indiscriminado de antimicrobianos. A nivel mundial, la expansión de este mecanismo de resistencia es inminente y las medidas de control son limitadas. Con el objeto de discutir los problemas relacionados a este mecanismo emergente de resistencia, reportamos un caso de Klebsiella pneumoniae productora de carbapenemasas en Huancayo, la Región de la Sierra Central de Perú.

Carbapenemases are one of the major mechanisms of antimicrobial resistance, usually due to the indiscriminate use of antibiotics. The expansion of this mechanism of resistance at world level is imminent and control measures are limited. In the region of the Central Sierra of Peru - Huancayo, we report a case of carbapenemase-producing Klebsiella pneumoniae, with the purpose of discussing the problems related to this emerging mechanism of antibiotic resistance.

Humans , Male , Adult , Klebsiella Infections/drug therapy , Klebsiella pneumoniae/drug effects , Anti-Bacterial Agents/pharmacology , Peru , Bacterial Proteins/metabolism , beta-Lactamases/metabolism , Klebsiella Infections/microbiology , Drug Resistance, Bacterial , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/enzymology
Rev. chil. infectol ; 35(3): 239-245, 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-959437


Resumen Introducción: La emergencia de Klebsiella productora de carbapenemasas resistente a colistín representa un desafío clínico y un problema emergente. Objetivo: Evaluar la mortalidad intrahospitalaria y sus potenciales factores de riesgo en pacientes internados con infecciones clínicas por Klebsiella pneumoniae productora de carbapenemasas (KPC) resistente a colistín. Material y Método: Realizamos un estudio de cohorte retrospectivo, incluyendo pacientes adultos admitidos a un hospital universitario de tercer nivel en Buenos Aires, infectados por KPC resistente a colistín. El evento primario considerado fue la mortalidad intrahospitalaria. Se utilizaron modelos generalizados lineales para evaluar potenciales predictores de dicho evento. Resultados: En total, se identificaron 18 pacientes hospitalizados que presentaron una infección clínica por esta bacteria durante el año 2016 y que fueron incluidos en el análisis final. La mortalidad intrahospitalaria en esta cohorte fue de 38,9%. La presencia de bacteriemia, la injuria renal aguda al momento del diagnóstico y la presencia de shock séptico se asociaron a la ocurrencia del evento primario. Conclusión: El desarrollo de infecciones clínicamente relevantes por KPC resistente a colistín en pacientes internados es frecuente y presenta una elevada mortalidad. En nuestra cohorte, la presencia de shock e injuria renal aguda al momento del diagnóstico se asociaron a un incrementado riesgo de mortalidad intrahospitalaria. Futuras investigaciones deberían corroborar estos hallazgos e investigar factores adicionales que permitan identificar tempranamente a aquellos pacientes que presentarán eventos desfavorables.

ABSTRACT Background: The emergence of colistin resistant carbapenemase-producing Klebsiella represents a therapeutic challenge and a worldwide problem. Aim: To estimate the in-hospital mortality and identify the associated risk factors among patients with colistin-resistant carbapenemase-producing Klebsiella pneumoniae (KPC) that present with a clinical infection. Methods: We carried a retrospective cohort study, including adult patients infected with colistin-resistant KPC hospitalized at a tertiary teaching hospital in Buenos Aires, Argentina during the year 2016. The main outcome was in-hospital mortality. We used generalized lineal models to evaluate potential predictors of mortality. Results: 18 patients that developed a colistin-resistant KPC clinical infection were identified and included in the final analysis. In-hospital mortality in this cohort was 38.9%. The presence of bacteremia, acute renal injury at the time of diagnosis and septic shock were associated with the main outcome. Conclusions: Infections due to colistin-resistant KPC among in-hospital patients was frequent and was associated with high mortality rate. In our cohort, both shock and acute kidney injury were associated with a higher likelihood of poor outcomes. Further studies are warranted to evaluate the role of these and others risk factors so as to aid in the early detection of high risk patients.

Humans , Male , Female , Adult , Middle Aged , Bacterial Proteins/metabolism , beta-Lactamases/metabolism , Klebsiella Infections/mortality , Hospital Mortality , Colistin , Klebsiella pneumoniae/drug effects , Anti-Bacterial Agents/therapeutic use , Argentina , Klebsiella Infections/enzymology , Klebsiella Infections/microbiology , Klebsiella Infections/drug therapy , Retrospective Studies , Risk Factors , Drug Resistance, Bacterial
Braz. j. microbiol ; 49(supl.1): 224-228, 2018. tab, graf
Article in English | LILACS | ID: biblio-1039272


ABSTRACT Enterobacter cloacae and E. aerogenes have been increasingly reported as important opportunistic pathogens. In this study, a high prevalence of multi-drug resistant isolates from Brazil, harboring several β-lactamase encoding genes was found. Several virulence genes were observed in E. aerogenes, contrasting with the E. cloacae isolates which presented none.

Humans , Male , Female , Adult , Middle Aged , Bacterial Proteins/metabolism , beta-Lactamases/metabolism , Enterobacter cloacae/isolation & purification , Enterobacter aerogenes/isolation & purification , Virulence Factors/metabolism , Enterobacteriaceae Infections/microbiology , Phylogeny , Bacterial Proteins/genetics , Virulence , beta-Lactamases/genetics , Brazil , Microbial Sensitivity Tests , Enterobacter cloacae/classification , Enterobacter cloacae/enzymology , Enterobacter cloacae/genetics , Enterobacter aerogenes/classification , Enterobacter aerogenes/enzymology , Enterobacter aerogenes/genetics , Virulence Factors/genetics , Middle Aged , Anti-Bacterial Agents/pharmacology
Braz. j. microbiol ; 48(3): 509-514, July-Sept. 2017. tab
Article in English | LILACS | ID: biblio-889143


Abstract The production of KPC (Klebsiella pneumoniae carbapenemase) is the major mechanism of resistance to carbapenem agents in enterobacterias. In this context, forty KPC-producing Enterobacter spp. clinical isolates were studied. It was evaluated the activity of antimicrobial agents: polymyxin B, tigecycline, ertapenem, imipenem and meropenem, and was performed a comparison of the methodologies used to determine the susceptibility: broth microdilution, Etest® (bioMérieux), Vitek 2® automated system (bioMérieux) and disc diffusion. It was calculated the minimum inhibitory concentration (MIC) for each antimicrobial and polymyxin B showed the lowest concentrations for broth microdilution. Errors also were calculated among the techniques, tigecycline and ertapenem were the antibiotics with the largest and the lower number of discrepancies, respectively. Moreover, Vitek 2® automated system was the method most similar compared to the broth microdilution. Therefore, is important to evaluate the performance of new methods in comparison to the reference method, broth microdilution.

Humans , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism , beta-Lactamases/metabolism , Enterobacteriaceae Infections/microbiology , Klebsiella Infections/microbiology , Klebsiella pneumoniae/drug effects , Microbial Sensitivity Tests/methods , Bacterial Proteins/genetics , beta-Lactamases/genetics , beta-Lactams/pharmacology , Drug Resistance, Bacterial , Enterobacter/drug effects , Enterobacter/genetics , Enterobacter/isolation & purification , Klebsiella pneumoniae/classification , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/isolation & purification , Polymyxin B/pharmacology
Braz. j. microbiol ; 48(2): 191-192, April.-June 2017.
Article in English | LILACS | ID: biblio-839376


Abstract Serratia marcescens is a Gram-negative rod intrinsically resistant to polymyxins and usually associated with wound, respiratory and urinary tract infections. The whole genome of the first GES-5-producing S. marcescens isolated from a Brazilian patient was sequenced using Ion Torrent PGM System. Besides blaGES-5, we were able to identify genes encoding for other β-lactamases, for aminoglycoside modifying enzymes and for an efflux pump to tetracyclines.

Humans , Serratia marcescens/enzymology , Serratia marcescens/genetics , beta-Lactamases/metabolism , DNA, Bacterial/genetics , DNA, Bacterial/chemistry , Genome, Bacterial , Sequence Analysis, DNA , Membrane Transport Proteins/genetics , Serratia marcescens/isolation & purification , Transferases/metabolism , beta-Lactamases/genetics , Brazil
Braz. j. microbiol ; 48(2): 196-197, April.-June 2017.
Article in English | LILACS | ID: biblio-839366


Abstract Worldwide increasing emergence of carbapenem-resistant Acinetobacter spp. has rendered the limited availability of effective antimicrobial agents and has become a major public health concern. In this study, we report the draft genome sequence of A. pittii TCM156, a multidrug-resistant isolate that harbored the blaOXA-357 gene. The genome sequence was further analyzed by various bioinformatics methods. The genome size was estimated to be 3,807,313 bp with 3508 predicted coding regions and G + C content is 38.7%. These findings have raised awareness of the possible emergence of OXA-type enzyme-producing A. pittii isolate in China.

Acinetobacter/genetics , beta-Lactamases/metabolism , Acinetobacter Infections/microbiology , DNA, Bacterial/chemistry , Genome, Bacterial , Sequence Analysis, DNA , Drug Resistance, Multiple, Bacterial , Base Composition , Acinetobacter/isolation & purification , Acinetobacter/drug effects , Acinetobacter/enzymology , DNA, Bacterial/genetics , China
Braz. j. microbiol ; 48(1): 159-166, Jan.-Mar. 2017. tab, graf
Article in English | LILACS | ID: biblio-839333


Abstract Staphylococcus aureus and Staphylococcus saprophyticus are the most common and most important staphylococcal species associated with urinary tract infections. The objective of the present study was to compare and to evaluate the accuracy of four phenotypic methods for the detection of beta-lactamase production in Staphylococcus spp. Seventy-three strains produced a halo with a diameter ≤28 mm (penicillin resistant) and all of them were positive for the blaZ gene. Among the 28 susceptible strain (halo ≥29 mm), 23 carried the blaZ gene and five did not. The zone edge test was the most sensitive (90.3%), followed by MIC determination (85.5%), but the specificity of the former was low (40.0%). The nitrocefin test was the least sensitive (28.9%). However, the nitrocefin test together with the disk diffusion method showed the highest specificity (100%). The present results demonstrated that the zone edge test was the most sensitive phenotypic test for detection of beta-lactamase, although it is still not an ideal test to detect this type of resistance since its specificity was low. However, the inhibition halo diameter of the penicillin disk can be used together with the zone edge test since the same disk is employed in the two tests. Combined analysis of the two tests shows a sensitivity of 90.3% and specificity of 100%, proving better sensitivity, especially for S. saprophyticus. This is a low-cost test of easy application and interpretation that can be used in small and medium-sized laboratories where susceptibility testing is usually performed by the disk diffusion method.

beta-Lactamases/genetics , beta-Lactamases/metabolism , Microbial Sensitivity Tests , beta-Lactam Resistance , Staphylococcal Infections/microbiology , Urinary Tract Infections/microbiology , Penicillin Resistance , Sensitivity and Specificity , Disk Diffusion Antimicrobial Tests , Staphylococcus saprophyticus/drug effects , Staphylococcus saprophyticus/genetics , Staphylococcus saprophyticus/metabolism , Genotype
Braz. j. infect. dis ; 21(1): 57-62, Jan.-Feb. 2017. tab, graf
Article in English | LILACS | ID: biblio-839184


Abstract The mechanisms involved in the uncommon resistance phenotype, carbapenem resistance and broad-spectrum cephalosporin susceptibility, were investigated in 25 Pseudomonas aeruginosa clinical isolates that exhibited this phenotype, which were recovered from three different hospitals located in São Paulo, Brazil. The antimicrobial susceptibility profile was determined by CLSI broth microdilution. β-lactamase-encoding genes were investigated by PCR followed by DNA sequencing. Carbapenem hydrolysis activity was investigated by spectrophotometer and MALDI-TOF assays. The mRNA transcription level of oprD was assessed by qRT-PCR and the outer membrane proteins profile was evaluated by SDS-PAGE. Genetic relationship among P. aeruginosa isolates was assessed by PFGE. Carbapenems hydrolysis was not detected by carbapenemase assay in the carbapenem-resistant and cephalosporin-susceptible P. aueruginosa clinical isolates. OprD decreased expression was observed in all P. aeruginosa isolates by qRT-PCR. The outer membrane protein profile by SDS-PAGE suggested a change in the expression of the 46 kDa porin that could correspond to OprD porin. The isolates were clustered into 17 genotypes without predominance of a specific PFGE pattern. These results emphasize the involvement of multiple chromosomal mechanisms in carbapenem-resistance among clinical isolates of P. aeruginosa, alert for adaptation of P. aeruginosa clinical isolates under antimicrobial selective pressure and make aware of the emergence of an uncommon phenotype among P. aeruginosa clinical isolates.

Humans , Pseudomonas aeruginosa/drug effects , Carbapenems/pharmacology , Cephalosporins/pharmacology , beta-Lactam Resistance/genetics , Anti-Bacterial Agents/pharmacology , Phenotype , Pseudomonas aeruginosa/enzymology , Pseudomonas aeruginosa/genetics , Spectrophotometry, Ultraviolet , Bacterial Outer Membrane Proteins , Bacterial Proteins/metabolism , beta-Lactamases/metabolism , Brazil , DNA, Bacterial , Microbial Sensitivity Tests , Electrophoresis, Gel, Pulsed-Field , Sequence Analysis, DNA , Porins/metabolism , Reverse Transcriptase Polymerase Chain Reaction
Rev. chil. infectol ; 33(6): 628-634, dic. 2016. graf, tab
Article in Spanish | LILACS | ID: biblio-844416


Background: Urinary tract infections (UTIs) caused by extended-spectrum betalactamases (ESBL) are an increasingly common problem. Aim: To develop an association model to allow an early detection of ESBL-producing microorganisms. Methods: A prospective observational cohort study was undertaken among patients admitted with a diagnosis of culture-proven UTI to the Internal Medicine Ward of the Hospital Naval Almirante Nef between February and November, 2011. Patients with polimicrobial cultures were excluded from analyses, which was undertaken using multiple logistic regression. Results: Two-hundred and forty-nine patients were analysed and 35 (14%) presented an ESBL-producing microorganism. Seventy-one percent were female and the mean age was 70,7 ± 16,9 years. A history of a recent hospitalization (< 3 months) or institutionalization (p = 0.027), previous infections by an ESBL-producing bacteria (p < 0.001), recent antimicrobial use (p = 0.013) and metastatic cancer (p = 0.007) were independently associated with a current UTI with an ESBL-producing pathogen. Discussion: Our findings are similar to those found in other populations. This tool offers assistance to clinicians who need to choose an appropriate antimicrobial therapy. This model needs to be validated prior to implementation.

Introducción: La infección del tracto urinario (ITU) por microorganismos productores de β-lactamasas de espectro extendido (BLEE) es un problema infectológico creciente. Objetivo: Determinar factores de riesgo predisponentes a infecciones por microorganismos productores de BLEE. Pacientes y Método: Cohorte prospectiva de pacientes > 18 años ingresados al Servicio de Medicina Interna del Hospital Naval Almirante Nef de Viña del Mar desde febrero a noviembre de 2011 con diagnóstico de ITU confirmado en un urocultivo. Se excluyeron pacientes con urocultivos polimicrobianos. El análisis se hizo mediante una regresión logística múltiple. Resultados: Se analizaron 249 pacientes, 35 (14%) presentaron un microorganismo productor de BLEE. El 71% fueron mujeres y la edad promedio 70,7 ± 16,9 años. El antecedente de hospitalización en los últimos tres meses o el vivir institucionalizado (p = 0,027), la infección por bacteria productora de BLEE previa (p < 0,001), el uso de antimicrobianos recientes (p = 0,013) y el antecedente de cáncer metastásico (p = 0,007) se asociaron a la producción de BLEE. Discusión: Los factores encontrados en la presente cohorte están de acuerdo a lo descrito en otras poblaciones. Esta herramienta ofrece asistencia para el médico clínico en la selección de la antibioterapia más apropiada. Es necesario validar este modelo previo a su implementación.

Humans , Male , Female , Aged , Urinary Tract Infections/microbiology , beta-Lactamases/metabolism , Gram-Negative Aerobic Bacteria/enzymology , Gram-Positive Bacteria/enzymology , Prospective Studies , Risk Factors , Community-Acquired Infections/microbiology
Braz. j. microbiol ; 47(supl.1): 31-37, Oct.-Dec. 2016. tab
Article in English | LILACS | ID: biblio-839327


ABSTRACT During the last 30 years there has been a dissemination of plasmid-mediated β-lactamases in Enterobacteriaceae in Brazil. Extended spectrum β-lactamases (ESBL) are widely disseminated in the hospital setting and are detected in a lower frequency in the community setting. Cefotaximases are the most frequently detected ESBL type and Klebsiella pneumoniae is the predominant species among ESBL producers. Klebsiella pneumoniae carbapenemase-producing Enterobacteriaceae became widely disseminated in Brazil during the last decade and KPC production is currently the most frequent resistance mechanism (96.2%) in carbapenem resistant K. pneumoniae. To date KPC-2 is the only variant reported in Brazil. Polymyxin B resistance in KPC-2-producing K. pneumoniae has come to an alarming rate of 27.1% in 2015 in São Paulo, the largest city in Brazil. New Delhi metallo-β-lactamase was detected in Brazil in 2013, has been reported in different Brazilian states but are not widely disseminated. Antimicrobial resistance in Enterobacteriaceae in Brazil is a very serious problem that needs urgent actions which includes both more strict adherence to infection control measures and more judicious use of antimicrobials.

Humans , Drug Resistance, Bacterial , Enterobacteriaceae/drug effects , Enterobacteriaceae Infections/microbiology , Enterobacteriaceae Infections/epidemiology , Anti-Infective Agents/pharmacology , Plasmids/genetics , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , beta-Lactamases/genetics , beta-Lactamases/metabolism , Brazil/epidemiology , Polymyxins/therapeutic use , Polymyxins/pharmacology , beta-Lactams/therapeutic use , beta-Lactams/pharmacology , Enterobacteriaceae/enzymology , Enterobacteriaceae/genetics , Anti-Infective Agents/therapeutic use , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology