RESUMO
Klebsiella pneumoniae strains producing K. pneumoniae carbapenemase (KPC) cause serious infections in debilitated and immunocompromised patients and are associated with prolonged hospital stays and increased mortality rates. Daptomycin is a lipopeptide used against Staphylococcus aureus infection and considered inactive against Gram-negative bacteria. We investigated the effectiveness of a daptomycin-meropenem combination by synergy kill curve and a pharmacokinetic/pharmacodynamic model. The combination may represent a novel therapeutic strategy against infections caused by KPC-producing K. pneumoniae strains.
Assuntos
Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Daptomicina/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Tienamicinas/farmacologia , beta-Lactamases/metabolismo , Proteínas de Bactérias/genética , Meropeném , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/enzimologia , beta-Lactamases/genéticaRESUMO
During the period 1993-2001, a total of 1,499 pneumococci isolates were recovered through the Argentinean surveillance of Streptococcus pneumoniae causing invasive disease in children under 6 years of age, 3.5% of which were erythromycin resistant. Among the 50 erythromycin-resistant strains available, 58% (n=29) harbored mefA/E genes (15 mefA, 30%; and 14 mefE, 28%), 34% (n=17) ermB, and 6% (n=3) both mefA/E plus ermB genes, while one isolate was negative for all the acquired genes studied. The England14-9 (42%), Poland6B-20 (20%) and Spain9V-3 (16%) clones were responsible for the emergence of pneumococcal macrolide resistance in pediatric population from Argentina.
Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Eritromicina/farmacologia , Genes Bacterianos , Proteínas de Membrana/genética , Metiltransferases/genética , Infecções Estreptocócicas/microbiologia , Streptococcus pneumoniae/genética , Argentina/epidemiologia , Criança , Pré-Escolar , Células Clonais , Humanos , Lactente , Infecções Estreptocócicas/epidemiologia , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificaçãoRESUMO
During the period 1993-2001, a total of 1,499 pneumococci isolates were recovered through the Argentinean surveillance of Streptococcus pneumoniae causing invasive disease in children under 6 years of age, 3.5% of which were erythromycin resistant. Among the 50 erythromycin-resistant strains available, 58% (n=29) harbored mefA/E genes (15 mefA, 30%; and 14 mefE, 28%), 34% (n=17) ermB, and 6% (n=3) both mefA/E plus ermB genes, while one isolate was negative for all the acquired genes studied. The England14-9 (42%), Poland6B-20 (20%) and Spain9v-3 (16%) clones were responsible for the emergence of pneumococcal macrolide resistance in pediatric population from Argentina.
En el marco del programa de vigilancia regional SIREVA, se analizaron 1499 aislamientos de Streptococcus pneumoniae causantes de enfermedad invasiva en menores de 6 años, recuperados entre 1993 y 2001. Se detectó un 3,5% de resistencia a eritromicina. De los 50 aislamientos resistentes a eritromicina que pudieron ser estudiados, el 58% (n=29) tenían los genes mefA/E (15 mefA, 30% y 14 mefE, 28%), el 34% (n=17) el gen ermB y el 6% (n=3) la combinación de genes mefA/E y ermB. Sólo un aislamiento fue negativo para todos los genes analizados. Los clones internacionales England14-9, Poland6B-20 y Spain9v-3 representaron el 78% del total de aislamientos resistentes (42, 20 y 16%, respectivamente) y se consideraron los responsables de la emergencia de la resistencia a macrólidos entre los neumococos que afectan a la población pediátrica de Argentina.
Assuntos
Criança , Pré-Escolar , Humanos , Lactente , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Eritromicina/farmacologia , Genes Bacterianos , Proteínas de Membrana/genética , Metiltransferases/genética , Infecções Estreptocócicas/microbiologia , Streptococcus pneumoniae/genética , Argentina/epidemiologia , Células Clonais , Infecções Estreptocócicas/epidemiologia , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificaçãoRESUMO
Se demostro que la vigilancia activa de colonización con enterococos resistentes a vancomicina (ERV) resulta costo-efectiva y que es capaz de limitar la presencia de esos patógenos en los hospitales. El objetivo de este trabajo fue evaluar el impacto de una forma de vigilancia menos estricta a través de los resultados de los estudios de prevalencia de un día y del número anual de pacientes infectados con ERV. En los cortes de prevalencia, se estudiaron todos los pacientes hospitalizados en días determinados, a través de hisopados rectales cultivados en medio BEAA con 6 ug/ml de vancomicina (VAN). También se estudiaron todos los aislamientos de enterococos provenientes de materiales clinicamente significativos a lo largo de los años. La resistencia a VAN fue confirmada por difusión, Etest y PCR especifica para lo genes vanA, vanB, o van C. La relación clonal fue establecida por electroforesis en campos pulsados cor cortes con la enzima Smal. El porcentaje de colonización rectal de ERV en los cortes de prevanlencia no registró un aumento significativo entre 2002 y 2007 (p > 0.05). La diversidad clonal mostró una baja tendencia hacia la diseminación intrahospitalaria de los ERV. El número de bacteriemias por ERV se mantuvo en niveles aceptables y la mayoria de las infecciones estuvieron localizadas en el tracto urinario. Concluyendo, el número de pacientes colonizados aumentó en forma sostenida pero sin diferencias significativas entre los distintos años. El número de pacientes severamente infectados con ERV hasta el momento ha sido escaso. Esto pareceria indicar que la estrategia elegida ha resultado efectiva.
Assuntos
Atenção Terciária à Saúde , Enterococcus/virologia , Prevalência , Programa de SEER , Resistência a Vancomicina , Estudos Observacionais como AssuntoRESUMO
Intestinal tract colonization with vancomycin resistant enterococci (VRE) was studied during five months and 25 days. Out of 171 patients hospitalized in the intensive care unit, 124 (73%) were included in this study. Thirty five of them (28%) were recognized as colonized with VRE. VRE isolates (n = 35) were identified as Enterococcus faecium (n = 18), Enterococcus gallinarum (n = 16), and Enterococcus raffinosus (n = 1). All of them were resistant to vancomycin (MIC90 = 512 microg/ml) and to teicoplanin (MIC90 = 32 microg/ml), having the vanA gene. By means of molecular methods a high homology was found among E. faecium and E. gallinarum isolates, respectively, suggesting their spread as a kind of outbreak. No significant differences in age or sex were found among colonized and non-colonized patients (p > 0.05). On the other hand, the hospitalization time and the use of broad-spectrum antibiotics were associated with colonization. From this study we highlight the importance of enhancing all measures of control and prevention of hospital infections, carefully analyzing the empiric antimicrobial schemes, trying to reduce the hospital stage, and following the surveillance to evaluate the efficacy of such procedures.
Assuntos
Enterococcus/isolamento & purificação , Unidades de Terapia Intensiva , Intestinos/microbiologia , Resistência a Vancomicina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Argentina , Estudos de Coortes , Comorbidade , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Teicoplanina/farmacologia , Vancomicina/farmacologiaRESUMO
En un período de cinco meses y 25 días se investigó la portación intestinal de enterococos resistentes a vancomicina (EVR). Se estudiaron 124 pacientes (73%) de 171 admitidos en la unidad de terapia intensiva (UTI), 35 de los cuales (28%) resultaron ser portadores. Los aislamientos de EVR (n=35) fueron identificados como Enterococcus faecium (n=18), Enterococcus gallinarum (n=16) y Enterococcus raffinosus (n=1). Todos los aislamientos estudiados fueron resistentes a vancomicina (VAN) (CIM90= 512 µg/ml) y teicoplanina (CIM90= 32 µg/ml) y portaban el gen vanA. Los estudios de tipificación molecular mostraron un alto grado de homología entre los aislamientos de E. faecium (un clon dominante) y E. gallinarum (dos tipos clonales), sugiriendo su diseminación a modo de brote. No se encontraron diferencias significativas con la edad y el sexo de los pacientes no portadores (p>0,05), pero si con el tiempo de hospitalización y el uso de esquemas antibióticos de amplio espectro (p<0,05), estando estos dos factores asociados al estado de portación. Se deduce de este estudio, la importancia de maximizar las medidas de prevención y control de las infecciones nosocomiales, analizar los esquemas empíricos empleados, tratar de disminuir el tiempo de hospitalización y continuar con los estudios de vigilancia para evaluar la eficacia de las acciones implementadas.
Intestinal tract colonization with vancomycin resistant enterococci (VRE) was studied during five months and 25 days. Out of 171 patients hospitalized in the intensive care unit, 124 (73%) were included in this study. Thirty five of them (28%) were recognized as colonized with VRE. VRE isolates (n = 35) were identified as Enterococcus faecium (n=18), Enterococcus gallinarum (n=16), and Enterococcus raffinosus (n=1). All of them were resistant to vancomycin (MIC90= 512 µg/ml) and to teicoplanin (MIC90= 32 µg/ml), having the vanA gene. By means of molecular methods a high homology was found among E. faecium and E. gallinarum isolates, respectively, suggesting their spread as a kind of outbreak. No significant differences in age or sex were found among colonized and non-colonized patients (p>0.05). On the other hand, the hospitalization time and the use of broad-spectrum antibiotics were associated with colonization. From this study we highlight the importance of enhancing all measures of control and prevention of hospital infections, carefully analyzing the empiric antimicrobial schemes, trying to reduce the hospital stage, and following the surveillance to evaluate the efficacy of such procedures.
Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enterococcus/isolamento & purificação , Unidades de Terapia Intensiva , Intestinos/microbiologia , Resistência a Vancomicina , Argentina , Estudos de Coortes , Comorbidade , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Genótipo , Estudos Prospectivos , Teicoplanina/farmacologia , Vancomicina/farmacologiaRESUMO
Enterococcusgallinarum is intrinsically resistant to low levels of vancomycin and has been described as a colonizing microorganism causing bacteraemia and infection among immunosupresed patients. Between August 2000 and February 2001, 15 highly glycopeptide-resistant E. gallinarum isolates, one from blood and the remaining from rectal swabs, were recovered in a general hospital of Buenos Aires Province, Argentina. All isolates were characterized by biochemical assays, and displayed MICs of vancomycin in the range 16-128 mg/l and MICs of teicoplanin in the range 16-32 mg/l. In all cases, PCR analysis yield positive results for both vanC1 and vanA genes. E. gallinarum isolates were classified as two clonal types by SmaI-PFGE: clone A (n = 8) and clone B (n = 7) and both harboured a transferable vanA element.
Assuntos
Proteínas de Bactérias/genética , Carbono-Oxigênio Ligases/genética , Conjugação Genética , Enterococcus/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/epidemiologia , Unidades de Terapia Intensiva , Resistência a Vancomicina , Antibacterianos/farmacologia , Argentina/epidemiologia , Elementos de DNA Transponíveis , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Eletroforese em Gel de Campo Pulsado , Enterococcus/classificação , Enterococcus/genética , Transferência Genética Horizontal , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Peptídeo Sintases/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Vigilância da População , Vancomicina/farmacologia , Resistência a Vancomicina/genéticaRESUMO
Intestinal tract colonization with vancomycin resistant enterococci (VRE) was studied during five months and 25 days. Out of 171 patients hospitalized in the intensive care unit, 124 (73
) were included in this study. Thirty five of them (28
) were recognized as colonized with VRE. VRE isolates (n = 35) were identified as Enterococcus faecium (n = 18), Enterococcus gallinarum (n = 16), and Enterococcus raffinosus (n = 1). All of them were resistant to vancomycin (MIC90 = 512 microg/ml) and to teicoplanin (MIC90 = 32 microg/ml), having the vanA gene. By means of molecular methods a high homology was found among E. faecium and E. gallinarum isolates, respectively, suggesting their spread as a kind of outbreak. No significant differences in age or sex were found among colonized and non-colonized patients (p > 0.05). On the other hand, the hospitalization time and the use of broad-spectrum antibiotics were associated with colonization. From this study we highlight the importance of enhancing all measures of control and prevention of hospital infections, carefully analyzing the empiric antimicrobial schemes, trying to reduce the hospital stage, and following the surveillance to evaluate the efficacy of such procedures.
RESUMO
The "Slidex MRSA Detection" test (Denka Seiken, Japan) is a latex agglutination assay able to detect PBP2a. We evaluated its ability to differentiate mecA-positive from mecA-negative coagulase-negative staphylococci. We included 100 coagulase-negative staphylococci clinical isolates belonging to 9 species, 54 mecA positive and 46 mecA negative, as characterized by PCR. The specificity achieved using the manufacturer's instructions was 100%, but the sensitivity was only 57%. To increase sensitivity, we introduced modifications into the standard protocol. Using either large inocula or oxacillin induction before test performance, we achieved 100% sensitivity.
Assuntos
Testes de Fixação do Látex/métodos , Oxacilina/farmacologia , Resistência às Penicilinas , Proteínas de Ligação às Penicilinas/análise , Staphylococcus/efeitos dos fármacos , Resistência às Penicilinas/genética , Kit de Reagentes para Diagnóstico/microbiologia , Sensibilidade e Especificidade , Especificidade da Espécie , Staphylococcus/classificação , Staphylococcus/genéticaRESUMO
Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen that has emerged over the last four decades, causing both nosocomial and community-acquired infections. Rapid and accurate detection of methicillin resistance in S. aureus is important for the use of appropriate antimicrobial therapy and for the control of nosocomial spread of MRSA strains. We evaluated the efficiency of conventional methods for detection of methicillin resistance such as the disk diffusion, agar dilution, oxacillin agar screen test, and the latex agglutination test MRSA-Screen latex, in 100 isolates of S. aureus, 79 mecA positive and 21 mecA negative. The MRSA-Screen latex (Denka Seiken, Niigata, Japón), is a latex agglutination method that detects the presence of PLP-2a, product of mecA gene in S. aureus. The PCR of the mecA gene was used as the "gold standard" for the evaluation of the different methods tested. The percentages of sensitivity and specificity were as follows: disk difusión 97 and 100%, agar dilution 97 and 95%, oxacillin agar screen test 100 and 100%, and MRSA-Screen latex, 100 and 100 %. All methods presented high sensitivity and specificity, but MRSA-Screen latex had the advantage of giving a reliable result, equivalent to PCR, in only 15 minutes.
Assuntos
Testes de Fixação do Látex , Resistência a Meticilina , Testes de Sensibilidade Microbiana/métodos , Staphylococcus aureus/efeitos dos fármacos , Proteínas de Bactérias/análise , Proteínas de Bactérias/genética , Proteínas de Transporte/análise , DNA Bacteriano/genética , Hexosiltransferases/análise , Resistência a Meticilina/genética , Muramilpentapeptídeo Carboxipeptidase/análise , Proteínas de Ligação às Penicilinas , Peptidil Transferases/análise , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Staphylococcus aureus/genéticaRESUMO
Staphylococcus aureus meticilino-resistente (MRSA) es un patógeno que ha emergido en las últimas cuatro décadas causando tanto infecciones nosocomiales como de la comunidad. La rápida y precisa detección de MRSA es relevante para guiar una apropiada terapia antibiótica y evitar la diseminación nosocomial de MRSA.En este trabajo se evaluó la eficiencia de métodos convencionales para la detección de meticilino-resistencia como difusión por discos, CIM en medio sólido, screening de oxacilina, y el nuevo test de aglutinación MRSA-Screen latex sobre 100 aislamientos de S. aureus, 79 mecA positivos y 21 mecA negativos. El test de aglutinación MRSA-Screen latex (Denka Seiken, Niigata, Japón) detecta la presencia de la PLP-2a, producto del gen mecA en cepas de S. aureus. La detección del gen mecA por PCR se utilizó como gold standard para comparar los resultados de los diferentes métodos. La sensibilidad y especificidad fueron 97 y 100 % para el método de difusión, 97 y 95 % para la CIM en medio sólido, 100 y 100 % para el screening de oxacilina y 100 y 100 % para MRSA-Screen latex. Todos los métodos presentaron alta sensibilidad y especificidad, pero el MRSA-Screen latex mostró la ventaja de poder brindar un resultado confiable, equivalente a la PCR, en sólo 15 minutos.
Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen that has emerged over the last four decades, causing both nosocomial and community-acquired infections. Rapid and accurate detection of methicillin resistance in S. aureus is important for the use of appropriate antimicrobial therapy and for the control of nosocomial spread of MRSA strains. We evaluated the efficiency of conventional methods for detection of methicillin resistance such as the disk diffusion, agar dilution, oxacillin agar screen test, and the latex agglutination test MRSA-Screen latex, in 100 isolates of S. aureus, 79 mecA positive and 21 mecA negative. The MRSA-Screen latex (Denka Seiken, Niigata, Japón), is a latex agglutination method that detects the presence of PLP-2a, product of mecA gene in S. aureus. The PCR of the mecA gene was used as the gold standard for the evaluation of the different methods tested. The percentages of sensitivity and specificity were as follows: disk difusión 97 and 100 %, agar dilution 97 and 95 %, oxacillin agar screen test 100 and 100 %, and MRSA-Screen latex, 100 and 100 %. All methods presented high sensitivity and specificity, but MRSA-Screen latex had the advantage of giving a reliable result, equivalent to PCR, in only 15 minutes.
Assuntos
Testes de Fixação do Látex , Resistência a Meticilina , Testes de Sensibilidade Microbiana/métodos , Staphylococcus aureus/efeitos dos fármacos , Proteínas de Bactérias/análise , Proteínas de Bactérias/genética , Proteínas de Transporte/análise , DNA Bacteriano/genética , Hexosiltransferases/análise , Resistência a Meticilina/genética , Muramilpentapeptídeo Carboxipeptidase/análise , Proteínas de Ligação às Penicilinas , Reação em Cadeia da Polimerase , Peptidil Transferases/análise , Sensibilidade e Especificidade , Staphylococcus aureus/genéticaRESUMO
Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen that has emerged over the last four decades, causing both nosocomial and community-acquired infections. Rapid and accurate detection of methicillin resistance in S. aureus is important for the use of appropriate antimicrobial therapy and for the control of nosocomial spread of MRSA strains. We evaluated the efficiency of conventional methods for detection of methicillin resistance such as the disk diffusion, agar dilution, oxacillin agar screen test, and the latex agglutination test MRSA-Screen latex, in 100 isolates of S. aureus, 79 mecA positive and 21 mecA negative. The MRSA-Screen latex (Denka Seiken, Niigata, Japón), is a latex agglutination method that detects the presence of PLP-2a, product of mecA gene in S. aureus. The PCR of the mecA gene was used as the [quot ]gold standard[quot ] for the evaluation of the different methods tested. The percentages of sensitivity and specificity were as follows: disk difusión 97 and 100
, agar dilution 97 and 95
, oxacillin agar screen test 100 and 100
, and MRSA-Screen latex, 100 and 100
. All methods presented high sensitivity and specificity, but MRSA-Screen latex had the advantage of giving a reliable result, equivalent to PCR, in only 15 minutes.
