Infecção primária da corrente sanguínea associada ao cateter venoso central em neonatos / Infección primaria del torrente sanguíneo asociada al catéter venoso central en neonatos resumen / Central venous catheter-associated primary bloodstream infection in neonates

RESUMO Objetivo: analisar a infecção primária da corrente sanguínea associada ao cateter venoso central em neonatos internados em unidades de terapia intensiva. Método: tratou-se de um estudo ecológico realizado em 2017 a partir de notificações de infecção primária da corrente sanguínea associada ao cateter venoso central ocorridas na capital de um estado da região Centro-Oeste do Brasil. Os dados foram coletados por meio de um formulário a partir de dois bancos de dados, municipal (2012 a 2016) e nacional (2014 a 2016). Resultados: a tendência temporal da densidade de incidência de infecção foi decrescente (p=0,019), com taxa de utilização de cateter venoso central de 45%. Os patógenos mais frequentes foram Klebsiella pneumoniae, Staphylococcus coagulase negativo e Enterobacter spp. Aumento de resistência às cefalosporinas e à oxacilina ocorreu para bactérias Gram-negativo e Gram-positivo, respectivamente. Conclusão: Conclui-se que houve uma redução na taxa de IPCS associada ao cateter em neonatos no período avaliado e os episódios infecciosos foram predominantemente causados por bactérias Gram-negativo, incluindo isolados multirresistentes aos antimicrobianos. Esses achados apontam para a importância e necessidade de estratégias educacionais para a equipe multiprofissional sobre vigilância de infecção, medidas preventivas e uso racional de antimicrobianos.

Resumen: Objetivo: analizar la infección primaria del torrente sanguíneo asociada al catéter venoso central en neonatos ingresados en unidades de cuidados intensivos. Método: se trató de un estudio ecológico, realizado en 2017, a partir de notificaciones de infección primaria del torrente sanguíneo asociada al catéter venoso central, ocurridas en la capital de un estado de la región Centro-Oeste de Brasil. Los datos fueron recogidos por medio de un formulario de dos bases de datos, municipal (2012 a 2016) y nacional (2014 a 2016). Resultados: la tendencia temporal de la densidad de incidencia de infección fue decreciente (p=0,019), con tasa de utilización de catéter venoso central del 45%. Los patógenos más frecuentes fueron Klebsiella pneumoniae, Staphylococcus coagulase negativa y Enterobacter spp. Aumento de resistencia a las cefalosporinas y a la oxacilina ocurrió para bacterias Gramnegativas y Grampositivas, respectivamente. Conclusión: hubo una reducción en la tasa de infección primaria del torrente sanguíneo asociada al catéter en neonatos en el período evaluado, y los episodios infecciosos fueron predominantemente causados por bacterias gramnegativas, incluyendo aislados multirresistentes a los antimicrobianos. Estos hallazgos señalan la importancia y necesidad de estrategias educativas para el equipo multiprofesional sobre vigilancia de infecciones, medidas preventivas y uso racional de antimicrobianos.

ABSTRACT Objective: to analyze primary bloodstream infections associated with central venous catheter in neonates admitted to intensive care units. Method: ecological study, conducted in 2017, from reports of primary bloodstream infections associated with central venous catheter, which occurred in the capital of a state in the Midwest region of Brazil. Data were collected using a form from two databases, municipal (2012 to 2016) and national (2014 to 2016). Results: the temporal trend of the infection incidence density was decreasing (p=0.019), with a central venous catheter use rate of 45%. The most frequent pathogens were Klebsiella pneumoniae, Coagulase-negative staphylococci, and Enterobacter spp. Increased resistance to cephalosporins and oxacillin occurred for Gram-negative and Gram-positive bacteria, respectively. Conclusion: There was a reduction in the rate of catheter-associated primary bloodstream infection in neonates in the period evaluated, and the infectious episodes were predominantly caused by Gram-negative bacteria, including antimicrobial multi-resistant isolates. These findings point to the importance and need for educational strategies for the multiprofessional team on infection surveillance, preventive measures, and rational use of antimicrobials.

Multirresistencia de Escherichia coli y Klebsiella pneumoniae provenientes de pacientes con infección del tracto urinario adquirida en la comunidad / Escherichia coli and Klebsiellap neumoniae multiresistance from patients with urinary tract infection acquired in the community

Introducción: El incremento de la multirresistencia bacteriana constituye un problema de salud pública a nivel internacional. Objetivos: Determinar la susceptibilidad antimicrobiana y los patrones de multirresistencia en cepas de Escherichia coli y Klebsiella pneumoniae aisladas de urocultivos. Métodos: Se realizó un estudio descriptivo retrospectivo en el Centro Municipal de Higiene, Epidemiología y Microbiología, municipio Güines, provincia Mayabeque, Cuba, en el periodo comprendido de enero a diciembre de 2017. El estudio incluyó 250 cepas de Escherichia coli y 62 de Klebsiella pneumoniae aisladas e identificadas de muestras de orina de pacientes con infección del tracto urinario adquirida en la comunidad. La susceptibilidad antimicrobiana fue evaluada con el método de difusión en agar empleado la técnica de Kirby Bauer. Resultados: En Escherichia coli se observó niveles de resistencia superiores al 60 por ciento a los antimicrobianos ácido nalidíxico, cefotaxima, trimetoprim - sulfametoxazol y ceftazidima. La nitrofurantoína y la amikacina presentaron 88,8 por ciento y 83,8 por ciento de efectividad, respectivamente. Se apreció en Klebsiella pneumoniae altos valores de resistencia a ceftazidima, trimetoprim - sulfametoxazol y ácido nalidíxico. Amikacina, presentó niveles de sensibilidad de un 71 por ciento. La resistencia a las cefalosporinas de tercera generación se detectó en 78 (31,2 por ciento) de Escherichia coli y 26 (41,9 por ciento) de Klebsiella pneumoniae. De los aislados de Escherichia coli 143 (57,2 por ciento) y Klebsiella pneumoniae 35 (56,4 por ciento) presentaron multidrogoresistencia. Conclusiones: Existe la circulación de cepas resistentes a cefalosporinas de tercera generación y multidrogorresistentes causantes de infecciones de las vías urinarias adquiridas en la comunidad y se informa sobre los antibióticos (nitrofurantoína y amikacina) que podrían ser utilizados para combatirlas de forma empírica en esta área geográfica(AU)

Introduction: The increase of bacterial multiresistance constitutes a public health problem at the international level. Objectives: To determine antimicrobial sensitivity and multiresistance patterns in strains of Escherichia coli and Klebsiellapneumoniae isolated from urine cultures. Methods: A retrospective, descriptive study was conducted at the Municipal Center for Hygiene, Epidemiology and Microbiology, Güines municipality, Mayabeque Province, Cuba, in the period from January to December, 2017. The study included 250 Escherichia coli and 62 Klebsiellapneumoniae strains isolated and identified from urine samples from patients with urinary tract infection acquired in the community. Antimicrobial sensitivity was evaluated with the method of diffusion in agar using Kirby Bauer´s technique. Results: In Escherichia coli, resistance levels higher than the 60% were observed in antimicrobial nalidixic acid, cefotaxime, trimethoprim-sulfamethoxazole and ceftazidime. Nitrofurantoin and amikacin presented 88.8 percent and 83.8 percent of effectiveness, respectively. High values of resistance to ceftazidime, trimethoprim-sulfamethoxazole and nalidixic acid were present in Klebsiellapneumoniae. Amikacin presented sensitivity levels of 71 percent. Resistance to third-generation cephalosporins was detected in 78 (31.2 percent) of Escherichia coli and 26 (41.9 percent) Klebsiellapneumoniae. From the Escherichia coli and Klebsiellapneumoniae isolates, 143 (57.2 percent) and 35 (56.4 percent),respectively, presented multidrug resistance. Conclusions: There is circulation of strains which are resistant to third generation cephalosporins and multidrug resistants that cause urinary tract infections acquired in the community and there are reports on antibiotics (nitrofurantoin and amikacin) that might be used to combat them empirically in this geographical area(AU)

Resistencia de Staphylococcus aureus frente a cefalosporinas en la sepsis neonatal y puerperal / Staphylococcus Aureus Resistance against Cephalosporins in Neonatal and Puerperal Sepsis

Introducción: El mecanismo más común de actividad antibiótica es la interferencia en la síntesis de la pared celular bacteriana. Las cefalosporinas tienen el mismo mecanismo de acción que las penicilinas; sin embargo, tienen un espectro antibacteriano más amplio, son resistentes a muchas b-lactamasas y tienen propiedades farmacocinéticas mejoradas. Objetivos: Identificar por servicios los gérmenes aislados y determinar la resistencia del Staphylococcus aureus a las cefalosporinas. Método: Se realizó un estudio retrospectivo, transversal y descriptivo en hospital Ginecobstétrico de Guanabacoa desde enero de 2014 hasta diciembre de 2016. Se seleccionaron como variables los gérmenes aislados y el patrón de resistencia del germen que predominó frente a todas las generaciones de cefalosporinas. Resultados: En el servicio de neonatología el mayor aislamiento fue en el hemocultivo seguido del catéter venoso (19 pacientes) y tubo endotraqueal. En el servicio de Obstetricia, los loquios y el sitio quirúrgico fue donde se aisló mayor número (69 y 31 pacientes, respectivamente). Conclusiones: El germen más frecuente aislado en ambos servicios fue el Staphylococcus aureus y la resistencia a las cefalosporinas fue muy elevado(AU)

Introduction: The synthesis interference of bacterial cell wall is the most common antibiotic mechanism. Cephalosporins have the same mechanism of action as penicillin. However, they have wider antibacterial spectrum, they are more resistant to B-lactamases and better pharmacokinetics properties. Additionally, cephalosporins have higher activity in front of gram-negative bacteria than penicillin. Objective: To identify isolated germs in these services and to determine the Staphylococcus aureus resistance to cephalosporins. Method: A retrospective, transversal and descriptive study was conducted in Guanabacoa Gynecobstetric hospital from January 2014 to December 2016. selected variables as isolated microorganism, and resistance pattern in front of cephalosporin generations. The isolated germs and the resistance pattern of the germ that prevailed against all generations of cephalosporins were selected as variables. In the Obstetrics Service, the largest number of germs was isolated in the lochia and surgical sites. (69 and 31, respectively). Results: In neonatology service, the most frequent isolation occurred in blood culture (35), venous catheter (19) and endotracheal tube (10). In Obstetric service, the most frequent isolation occurred in liquors (69) and the surgical site isolated (31). Conclusions: Staphylococcus Aureus was the main microorganism isolated in hospital and its cephalosporin resistance was very high(AU)

Ceftaroline resistance in Staphylococcus pseudintermedius gene mecA carriers / Resistência à ceftarolina em Staphylococcus pseudintermedius portadores do gene mecA

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) being a constant concern, ceftaroline fosamil has been recently approved as a new cephalosporin, active against MRSA, for use in humans; only rare cases of resistance have been reported till date. There is no report of resistance to ceftaroline in Staphylococcus pseudintermedius, which is the main bacterium causing dermatitis and otitis in dogs. To evaluate staphylococcal resistance to ceftaroline, 35 isolates of methicillin-resistant S. pseudintermedius (MRSP), carrying the mecA gene, from 26 dogs with folliculitis and nine dogs with external otitis, underwent disk diffusion test with cefoxitin, oxacillin, and ceftaroline. Tests with cefoxitin and oxacillin showed > 90% sensitivity in methicillin resistance detection. In the disk diffusion test, 97.14% (34/35) were resistant to cefoxitin, 94.29% (33/35) to oxacillin, and 31.43% (11/35) to ceftaroline. Of the ceftaroline-resistant strains, 27.27% (3/11) were obtained from the ears of dogs while the rest (8/11) were from the skin. The current report is the first description of MRSP resistance to ceftaroline.(AU)

Infecções causadas por Staphylococcus aureus resistente à meticilina (MRSA) são uma preocupação médica constante. A ceftarolina fosamila é uma nova cefalosporina ativa contra Staphylococcus aureus resistente à meticilina recentemente aprovada para uso em humanos e raros casos de resistência relatados até agora. Não há relatos de resistência à ceftarolina em Staphylococcus pseudintermedius, principal bactéria causadora de dermatite e otite em cães. Com o objetivo de avaliar a resistência estafilocócica à ceftarolina, 35 amostras de S. pseudintermedius resistentes à meticilina (MRSP), portadoras do gene mecA, provenientes de 26 cães com foliculite e 9 com otite externa foram submetidos ao teste de disco-difusão com cefoxitina, oxacilina e ceftarolina. Os testes realizados com cefoxitina e oxacilina mostraram mais de 90% de sensibilidade na detecção da resistência à meticilina em ambas. No teste da disco-difusão, 97,14% (1/35) foram resistentes à cefoxitina, 94,29% (3/35) à oxacilina e 31,43% (11/35) à ceftarolina. Das cepas resistentes às ceftarolina, 27,27 (3/11) foram provenientes de ouvido de cães e as demais (8/11), provenientes da pele, sendo essa primeira descrição de resistência de MRSP à ceftarolina na literatura atual.(AU)

Salicylic Acid Reduces OmpF Expression, Rendering Salmonella enterica Serovar Typhimurium More Resistant to Cephalosporin Antibiotics / 전남의대학술지

Salmonella enterica serovar Typhimurium is one of the most important bacterial pathogens causing diarrhea. The resistance of S. typhimurium to antimicrobial agents, which has recently been isolated from patients, is causing serious problems. We investigated the effects of salicylic acid (Sal) and acetyl salicylate (AcSal) on the susceptibility of S. typhimurium to cephalosporin antibiotics, which are known to increase resistance to cephalosporin and quinolone antibiotics. The MIC of cephalosporin antibiotics was higher than that of the media without Sal. The rate of accumulation of ethidium bromide (EtBr) in the bacteria by the outer membrane protein (Omp) was not different from that of the bacteria cultured in the medium containing Sal. However, Carbonyl cyanide-m-chlorophenylhydrazone (CCCP), an inhibitor of bacterial efflux pumps, significantly reduced the rate of accumulation of EtBr in bacteria cultured on Sal containing medium. In the medium containing CCCP, the MIC of the antimicrobial agent tended to decrease as compared with the control. In addition, the MIC of the bacteria treated with CCCP and Sal was higher than that of the antimicrobial agent against the CCCP treated experimental bacteria. These results suggest that Sal decreases the expression of OmpF in the Omp of S. typhimurium and reduces the permeability of cephalosporin antibiotics to bacteria, which may induce tolerance to cephalosporin antibiotics.

Phenotypic and molecular detection of esbl-producing genes tem-1 and shv-1 in uropathogenic escherichia coli isolates

Background: Spread of pathogenic strains carrying genes Extended-spectrum beta-lactamases [ESBL] is one of the major health concerns in the world. These genes caused due to the inefficient beta-lactam antibiotics in the treatment of infectious diseases. The purpose of this study was to determine the prevalence of TEM-1 and SHV-1 beta-lactamase genes in uropathogenic E. coif isolates from the city of Khorramabad

Methods: A total of 100 E. coli isolates were collected from patients with urinary tract infections in clinical laboratories from city of Khorramabad. Originality isolates were confirmed by biochemical tests. ESBLs positives isolates were determined by using a combined disk based instruction the Clinical and Laboratory Standards Institute [CLSI] and then all the positive isolates were studied by PCR assay for the presence of genes TEM-1 and SHV-1

Results: Thirty one [31%] out of 100 E. coif isolates were ESBL positive based on the results of combined disc tests. PCR analysis using the specific primers revealed that 18 isolates [58.06%] contained p-lactamases genes encoding TEM, and while none of isolates did not carry SHV gene

Conclusion: The relatively high prevalence of resistance genes to third generation of cephalosporins among the E. coif isolates was found which indicates a challenge in successful treatment with current antibiotics

Detección molecular de belactamasas de espectro extendido (BLEE) en enterobacterias aisladas en Asunción / Molecular detection of extended spectrum beta-lactamase (esbl) in enterobacteria isolated in Asunción

Las betalactamasas de espectro extendido (BLEE), son enzimas responsables de la hidrólisis del anillo betalactámico de penicilinas y cefalosporinas, excepto carbapemenes, inhibiendo así su actividad terapéutica. Si bien es posible la detección fenotípica de este mecanismo de resistencia por métodos convencionales, sólo los métodos moleculares permiten la identificación del gen responsable de dicha resistencia. El objetivo de este estudio descriptivo retrospectivo fue identificar los genes blaCTX-M2, blaPER-2, blaSHV y blaTEM, en aislamientos de enterobacterias productoras de BLEE,; de muestras clínicas colectadas entre julio 2007 y abril 2008, provenientes de dos hospitales de referencia de Asunción, Paraguay. La detección molecular de los genes se realizó por reacción en cadena de la polimerasa empleando oligonucleótidos específicos. De los 232 aislados BLEE analizados, el 83% (n=192) portó al menos un gen bla, en el 17% (n=40) restante no fue detectado ninguno de los genes incluido en el estudio. Se observaron las siguientes frecuencias: 49% (94/192) blaCTX-M2, 45% (86/192) blaSHV, 40% (77/192) blaTEM y 7% (13/192) blaPER-2. En el 47% (90/192) se detectó más de un gen, siendo la combinación blaCTX-M2+blaTEM+blaSHV, la más frecuente observada en 32 aislados. El blaCTX-M2 como el gen más frecuente en este estudio; concuerda con lo reportado en nuestro país y en Argentina. Este es el primer reporte de la presencia de blaTEM y blaSHV en Paraguay. Es de gran importancia el estudio de otros genes codificantes de resistencia, considerando la emergencia de otras BLEE en la región como blaCTX-M15 con actividad predominantemente ceftazidimasa.

Extended spectrum beta-lactamases (ESBLs), are enzymes responsible for thehydrolysis of the beta-lactam ring and resistance to both cephalosporins and penicillins,except carbapenems, therefore inhibiting its therapeutics activity. Even though, detectionof the phenotypic resistance mechanism by conventional methods is possible, onlymolecular methods allow identification of the gene responsible for the resistance. Theobjective of this retrospective study was to identify the blaCTX-M2, blaPER-2, blaSHV, blaTEMgenes in ESBL-producing enterobacteriaceae isolates, recovered from clinical samples collected between July 2007 and April 2008, from two reference hospitals in Asunción,Paraguay. Molecular gene detection was performed by polymerase chain reaction usingspecifics oligonucleotides. Out of the tested 232 ESBL-producing isolates, 83% (n=192)carried at least one of the bla genes as follows; 49% (94/192) blaCTX-M2, 45% (86/192)blaSHV, 40% (77/192) blaTEM and 7% (13/192) blaPER-2. In the rest 17% (n=40) none of thegenes included in this study was detected; in 47% (90/192) more than one gene wasdetected, resulting blaCTX-M2 + blaTEM + blaSHV as the most frequent combination in 32isolates. The presence of blaCTX-M2, as the most frequent codifying genes of BLEE is inagreement with previous reports in Paraguay and Argentina. This is the first report of thepresence of blaTEM and blaSHV circulating in Paraguay. It is of much importance the study ofothers codifying resistance genes, taking into account the emergence of other BLEE in theregion, such as blaCTX-M15, predominantly with ceftazidimase activity.

Enterobacteriaceae resistant to third generation cephalosporins upon hospital admission: risk factors and clinical outcomes

Objectives: Evaluate risk factors and clinical outcomes of infections caused by Enterobacteriaceae resistant to third-generation cephalosporins present in samples collected upon hospital admission. Methods: Risk factors were evaluated using a 1:2 ratio case-control study. Influence of resistance on the appropriateness of antibiotic therapy, length of stay, and hospital mortality were prospectively evaluated. Characteristics independently associated with the presence of resistant enterobacteria were assessed by logistic regression. Results: Enterobacteria resistant to third-generation cephalosporins were quite common (26.0%). Male gender (OR: 2.66; 95% CI, 1.17-5.06; p = 0.019), invasive prosthesis (OR: 3.79; 95% CI, 1.29-11.08; p = 0.015), previous use of cephalosporins (OR: 2.77; 95% CI, 1.10-6.97; p = 0.029) and hospitalization in the last 6 months (OR: 5.33; 95% CI, 2.29-12.44; p < 0.001) were independently associated with the presence of these microorganisms. These bacteria were associated with higher frequency of inappropriate antimicrobial therapy, worse clinical response, and longer length of stay. Finally, older age, admission to the ICU, and site of infection other than urinary tract were independently associated to higher hospital mortality. Conclusions: Risk factors identified in this study may help in the choice of empirical antibiotic therapy for infected patients suspected of harboring these bacteria and in the early implementation of measures to avoid the spread of these bacteria in the hospital environment. .

Third-generation cephalosporin resistance in gram-negative bacteria in the community: a growing public health concern

No abstract available.

Third-generation cephalosporin resistance of community-onset Escherichia coli and Klebsiella pneumoniae bacteremia in a secondary hospital

BACKGROUND/AIMS: To enable appropriate antimicrobial treatment for community-onset infections in emergency departments (EDs), data are needed on the resistance profiles of Escherichia coli and Klebsiella pneumoniae, which are the main pathogens of community-onset bacteremia. METHODS: Records were reviewed of 734 patients with E. coli and K. pneumoniae bacteremia who visited the Daegu Fatima Hospital ED, Daegu, Korea between 2003 and 2009. We investigated the demographic data, clinical findings, and antimicrobial susceptibility patterns of the organisms. RESULTS: Of 1,208 cases of community-onset bacteremia, 62.8% were caused by E. coli or K. pneumoniae in an ED of a secondary care hospital. Five hundred and forty-eight cases of E. coli (75%) and 183 cases of K. pneumoniae (25%) were analyzed. Urinary tract infection (43.1%) was most common, followed by intra-abdominal infection (39%) and pneumonia (7.2%). Trimethoprim/sulfamethoxazole, fluoroquinolone, third-generation cephalosporin (3GC) and amikacin resistance rates among E. coli and K. pneumoniae were 22.8%, 19.6%, 6.2%, and 1.3%, respectively. In 2009, the rate of 3GC resistance (10.6%) was significantly higher, compared to the annual averages of 2003 to 2008 (6.1%; p = 0.03). Previous exposure to antibiotics was an independent risk factor for 3GC resistance in multivariate logistic regression analysis. CONCLUSIONS: The rate of 3GC resistance increased in community-onset infections, and previous exposure to antibiotics was an independent risk factor. Despite the increased 3GC resistance in community-onset infections, an amikacin combination therapy could provide an option for treatment of bacteremic patients with previous antibiotic exposure in an ED.

detection of ESBL-producing Escherichia coli in patients with symptomatic urinary tract infections using different diffusion methods in a rural setting

This study aimed to determine the prevalence of extended spectrum of beta lactamases [ESBLs], to compare different phenotypic methods for ESBL confirmation and to evaluate the antibiotic resistance patterns among ESBL-producing urinary Escherichia coli. Urinary E. coli isolates that were resistant to at least one of the three indicator cephalosporins [cefotaxime, cefpodoxime and ceftazidime] were tested for ESBL production using the double disc synergy test [DDST], the inhibitory potentiated disc diffusion [IPDD] test and the quantitative E-strip method. Of the 163 E. coli strains isolated, 80 [49%] were resistant to at least one of the three cephalosporins, and 38 [47.5%] tested positive for ESBLs by the IPDD test and the E-strip test. However, only15 [18.7%] strains tested positive by the DDST. Among the third-generation cephalosporins, cefpodoxime [46.1%] was the best screening indicator, followed by ceftazidime [43%] and cefotaxime [39.9%]. Most of the ESBL producers [97.3%] were resistant to three or more drugs, compared with 51.2% of non-ESBL producers. Compared with the DDST, the IPDD and E-strip tests appear to be preferable methods for detecting ESBLs, with better sensitivity [100%] and specificilty [97.6%] and positive predictive values [97.3%]. ESBL producers showed significantly [p < 0.05] higher resistance to tobramycin, co-amoxyclav and amikacin than did non-ESBL producers

Clinical and Molecular Epidemiology of Community-Onset Bacteremia Caused by Extended-Spectrum beta-Lactamase-Producing Escherichia coli over a 6-Year Period

Although extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-EC) has emerged as a significant community-acquired pathogen, there is little epidemiological information regarding community-onset bacteremia due to ESBL-EC. A retrospective observational study from 2006 through 2011 was performed to evaluate the epidemiology of community-onset bacteremia caused by ESBL-EC. In a six-year period, the proportion of ESBL-EC responsible for causing community-onset bacteremia had increased significantly, from 3.6% in 2006 to 14.3%, in 2011. Of the 97 clinically evaluable cases with ESBL-EC bacteremia, 32 (33.0%) were further classified as healthcare-associated infections. The most common site of infection was urinary tract infection (n=35, 36.1%), followed by biliary tract infections (n=29, 29.9%). Of the 103 ESBL-EC isolates, 43 (41.7%) produced CTX-M-14 and 36 (35.0%) produced CTX-M-15. In the multilocus sequence typing (MLST) analysis of 76 isolates with CTX-M-14 or -15 type ESBLs, the most prevalent sequence type (ST) was ST131 (n=15, 19.7%), followed by ST405 (n=12, 15.8%) and ST648 (n=8, 10.5%). No significant differences in clinical features were found in the ST131 group versus the other group. These findings suggest that epidemic ESBL-EC clones such as CTX-M-14 or -15 type ESBLs and ST131 have disseminated in community-onset infections, even in bloodstream infections, which are the most serious type of infection.

Clinical and Microbiological Characteristics of Healthcare-Associated Infections in Community-Onset Klebsiella pneumoniae Bacteremia

BACKGROUND: Although healthcare-associated (HCA) Klebsiella pneumoniae bacteremia constitutes a significant proportion of community-onset infection cases, its clinical and microbiologic characteristics have yet to be described in detail. In this study, we sought to delineate the clinical differences between community-associated (CA) and HCA K. pneumoniae bacteremia. MATERIALS AND METHODS: A total of 240 patients infected by community-onset K. pneumoniae bacteremia were included in this study, and the data from the patients with HCA K. pneumoniae bacteremia were compared to those with the CA bacteremia. Isolates were microbiologically characterized and serotyped using a PCR method. RESULTS: Of the total 240 patients infected with community-onset K. pneumoniae bacteremia, 140 (58.3%) were defined as HCA infection cases, and the remaining 100 patients were classified as CA infections. Multivariate analysis showed that use of percutaneous tubes, occurrence of a recent surgical operation, cases of pneumonia, neutropenia and solid tumor, and prior receipt of antibiotics were all significant factors associated with HCA bacteremia infection (all P<0.05). In terms of microbiologic characteristics, ciprofloxacin resistance (12.9% [18/140] vs. 4.0% [4/100], P=0.02) and extended-spectrum beta-lactamase production (12.1% [17/140] vs. 4.0% [4/100], P=0.03) were more common in HCA bacteremia than CA bacteremia, respectively. The K1 and K2 serotypes, which are considered virulent community strains, were observed to exist more frequently in CA bacteremia than in HCA bacteremia (34% [34/100] vs. 21.4% [30/140], P=0.03). The overall 30-day mortality of the study population was 17.5% (37/211), and there was a trend toward greater mortality in the HCA group than in the CA group (21.4% [27/126] vs. 11.8% [10/85]; P=0.07). CONCLUSIONS: Patients infected with HCA bacteremia accounted for a substantial proportion of all patients with community-onset K. pneumoniae bacteremia, and showed significantly different clinical and microbiological characteristics than those infected with CA bacteremia. HCA K. pneumoniae bacteremia represented a distinct subset of community-onset bacteremia characterized by antibiotic resistant pathogens, a finding which physicians should consider in providing optimal treatment of these cases.

Frecuencia de enzimas asociadas a sensibilidad disminuida a betalactámicos en aislados de enterobacterias, Caracas, Venezuela / Frequency of enzymes associated with reduced sensitivity to beta-lactamantibiotics in enterobacteria isolates, Caracas, Venezuela

Objective. To determine the frequency of enzymatic mechanisms associated with reduced sensitivity to broad-spectrum beta-lactam antibiotics in enterobacteria isolates obtained at hospital centers in Caracas, Venezuela.Methods. A cross-sectional study was conducted on enterobacteria isolated from patients at eight hospital centers in Caracas, Venezuela, from 15 October 2009 to 15 January 2010. The species were identified using conventional biochemical tests, and their susceptibility to antimicrobial drugs was assessed by antibiogram (Kirby-Bauer method), using the 2010 performance standards published by the Clinical and Laboratory Standards Institute. Beta-lactam-resistant genes were detected using an enhanced polymerase chain reaction assay.Results. Of 1 235 isolates, 207 (16.8%) exhibited resistance to third- and fourthgeneration cephalosporins, carbapenems, or both. They presented the following phenotypes: extended-spectrum beta-lactamase (ESBL), 93.8%; depressed AmpC, 4.3%; and carbapenemase, 1.9%. Further characterization of the first two phenotypes yielded the following breakdown of types: SHV, 36.7%; CTX-M-1 group, 22.3%; TEM, 21.7%; CTX-M-1 group with impermeability, 5.2%; two-enzyme combinations, 4.5%;CTX-M-2 group, 4.3%; PER, 3.4%; and KPC, 1.9%. The SHV type was predominant in the public hospital strains, whereas the CTX-M-1 group was most common in the strains from the private hospitals. Conclusions. Of the enzymatic mechanisms investigated, the SHV type was the most frequent, followed by the CTX-M-1 group and the TEM type. Also, a high percentageof type KPC was found. The research reported here is one of only a few multicenter studies that have been conducted in Venezuela to evaluate the frequency of this type of antimicrobial resistance mechanism, including phenotypical and molecular characterization...

Objetivo. Determinar la frecuencia de los mecanismos enzimáticos asociados a sensibilidad disminuida a los antibióticos betalactámicos de amplio espectro en aislados de enterobacteriasobtenidos de centros hospitalarios de Caracas, Venezuela. Métodos. Se realizó un estudio transversal con enterobacterias aisladas de pacientes de ocho centros hospitalarios de Caracas, Venezuela, desde el 15 de octubre de 2009 al 15 de enero de2010. La identificación se realizó mediante pruebas bioquímicas convencionales, y la susceptibilidada los antimicrobianos mediante antibiograma (Kirby-Bauer), según las normas de 2010 del Instituto de Estándares Clínicos y de Laboratorio. La detección de los genes de resistenciaa betalactámicos se realizó mediante amplificación por reacción en cadena de polimerasa. Resultados. De 1 235 aislados, 207 (16,8%) mostraron resistencia a cefalosporinas de terceray cuarta generación o a carbapenemes o a ambos. De esos, 93,8% presentaron fenotipo betalactamasa de espectro extendido (BLEE); 4,3%, fenotipo AmpC derreprimido, y 1,9%, fenotipocarbapenemasa. La caracterización de los dos primeros fenotipos determinó que 36,7% eran tipo SHV; 22,3%, grupo CTX-M-1; 21,7%, tipo TEM; 5,2%, grupo CTX-M-1 + impermeabilidad; 4,5%, combinación de dos enzimas; 4,3%, grupo CTX-M-2; 3,4%, tipo PER, y 1,9%, tipo KPC.Se observó un predominio del tipo SHV en las cepas obtenidas de hospitales públicos y del grupo CTX-M-1, en los privados. Conclusiones. De los mecanismos enzimáticos investigados, el tipo SHV fue el más frecuente,seguido del grupo CTX-M-1 y tipo TEM. Asimismo, se encontró un alto porcentaje de carbapenemasas tipo KPC. Este es uno de los pocos estudios multicéntricos realizados enVenezuela donde se evalúa la frecuencia de este tipo de mecanismo de resistencia a los antimicrobianos,incluida la caracterización fenotípica y molecular...

Comparative study on occurrence of class A and class C β -lactamase genes and their co-occurrence in Indian Enterobacteriaceae during years 2009 and 2010

OBJECTIVE@#To determine the occurrence of class A and class C β-lactamase genes and their co-occurrence in Indian Enterobacteriaceae.@*METHODS@#52 third generation cephalosporin resistant isolates were phenotypically detected by combination disk method and screened by PCR to identify class A and class C type β-lactamase genes.@*RESULTS@#Of the 52 isolates, 94.2% (49) were found harboring any of the bla(ESBL(s)). bla(CTX-M), bla(SHV) and bla(TEM) were present in 82.6% (43/52), 59.6% (31/52), and 42.3% (22/52) isolates, respectively. Of the 49 ESBL positive isolates 57.1% (28/49) showed co-occurrence of bla(ampC) with bla(ESBL(s)). On the contrary, the collection from 2009 showed their co-occurrence in 81.4% isolates.@*CONCLUSIONS@#The comparative study shows a downward trend for co-existence of bla(ESBL(s)) with bla(ampC) from 2009 to 2010. Further large scale studies are needed to address the co-occurrence of class A and class C β-lactamases in India and the resistance trend occurring over a period of time.

Cephalosporins susceptibility test in urinary tract infections

This study was conducted at the Al Kindy Teaching Hospital to determine the resistance patterns tocephalosporins of members of the family Enterobacteriaceae isolated from urinary tract infections [UTIS]. A total of 270 urine specimens were collected from February, 2008 to May, 2008. Determination the Resistance patterns to cephalosporins in Enterobacteriaceae isolated from urinary tract infection. Urine specimens were processed for culture, and susceptibility testing using Kirby-Bauer method. The minimum inhibitory concentration [MIC] was determined by twofold dilution. Escherichia coli was found to be the most organism, followed by Klebsiella spp. The results of susceptibility of isolates under study to different cephalosporins were moderately or highly resistant to many of the test agents. The observations on the minimum inhibitory concentrations [MICs] and minimum bactericaidal concentrations [MBCs] for the cephalosporins explained the high level of resistance to cephalothin and cefaclor, and a moderate level of resistance to cefotaxime, ceftazidime and cefixime. The increasing MIC of cephalosporins, especially third generation, indicates decreasing susceptibility of these organisms to these types of beta-lactam agents due to the production of extended spectrum beta-lactamases [ESBLs]

Detecção de metalo-beta-lactamases em amostras de pseudomonas aeruginosa isoladas em Porto Alegre, Rio Grande do Sul / Detection of metallo-beta-lactamase producing pseudomonas aeruginosa isolated in Porto Alegre,Rio Grande do Sul, Brazil

As metalo-beta-lactamases (MBLs) pertencem ao grupo 3 de beta-lactamases de espectro estendido, fazendo parte de uma classefuncional de metaloenzimas classificadas com base na sua capacidade de hidrolisar os carbapenemicos como o Imipenem e em suas caracteristicas de serem inibidas por agentes quelantes como o acido etilenodiamino tetra-acetico (EDTA) e acido 2-mercaptopropionico (2-MPA). Este estudo objetivou a deteccao de MBLs em amostras nosocomiais de P. aeruginosa resistentes a Ceftazidima, provenientes de um hospital de medio porte de Porto Alegre-RS. Foram analisados 113 isolados clinicos atraves de testes fenotipicos, sendo: 80 (70,7%) do trato respiratorio inferior, 24 (21,2%) urina, 3 (2,7%) hemocultura, 3 (2,7%) ponta de cateter, 2 (1,8%) colecao de cavidadese 1 (0,9%) liquor. Com relacao a producao de MBLs, detectou-se 35 amostras (31,0%) como sendo produtoras.

Metallo-beta-lactamases belongs to the group 3 of extended spectrum beta-lactamases, making part of a common functional class of metal enzymes classified based in their ability to hydrolyze Imipenem and in your characteristics of been inhibited by ions of chelating metals, like EDTA and 2-MPA. The aim of this study was detect MBLs in samples of P. aeruginosa resistant to ceftazidime in the patients of PortoAlegre- RS Brazil. The samples was provided of different clinical specimens like: 80 (70,7%) respiratory tract, 24 (21,2%) urine, blood 3 (2,7%), catheter 3 (2,7%), 2 (1,8%) corporeal secretions and 1 (0,9%) liquor. With regard to the MBLs production, we detect 35 (31%) as being producing.

Detection of extended spectrum beta-lactamase from clinical isolates in Davangere.

Extended spectrum beta-lactamase enzymes (ESBLs) are enzymes that have the ability to hydrolyze oxyiminocephalosporins and infections by isolates producing them are often difficult to treat. A study to detect the presence of these enzymes in isolates was conducted by our hospital. A total of 207 non repetitive isolates were screened for resistance to any of five screening agents. Those with suspicious profiles were checked for ESBL production by double-disk approximation or a synergy test. The isolates were also subjected to a phenotypic confirmation test as recommended by CLSI (formerly NCCLS). Various cephalosporins-beta-lactamase inhibitor combinations were also tested. Of the 204 (98.5%) screen-positive isolates, only 126 (61.7%) were identified as ESBL producers. Of these, 26.1% of the isolates were positive by using the double-disk synergy test (DDST) method alone, 13.4% were positive using the method recommended by CLSI, and 60.3% of the isolates were positive by both the DDST and CLSI methods. We also report a high percentage of resistance to cefoxitin (96.8%) indicating changes in porins.