RESUMO
Clostridium ramosum is an enteric anaerobic, endospore-forming, gram-positive rod with a low GC content that is rarely associated with disease in humans. We present a case of C. ramosum bacteraemia. To the best of our knowledge, this is the second case of C. ramosum bacteraemia in an elderly patient presenting with fever, abdominal pain and bilious emesis. We highlight the Gram stain variability, the lack of visualization of spores and the atypical morphology of the colonies that showed C. ramosum in a polymicrobial presentation that initially appeared to show monomicrobial bacteraemia. The microorganism was rapidly identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). We present a comprehensive literature review of 32 cases of clinical infections by C. ramosum in which we describe, if available, sex, age, clinical symptoms, predisposing conditions, other organisms present in the blood culture, other samples with C. ramosum , identification methodology, treatment and outcome.
RESUMO
The association of Comamonas kerstersii with peritonitis resulting from the presence of perforated appendix has previously been described by our research team. In the present study, we describe the isolation of this microorganism from two forms of unusual presentations of C. kerstersii infection not previously described in the literature: localized intra-abdominal infection (psoas abscess) and pelvic peritonitis.
Assuntos
Farmacorresistência Bacteriana/genética , Lincosamidas/metabolismo , Nucleotidiltransferases/genética , Streptococcus agalactiae/genética , Proteínas de Bactérias/genética , Clindamicina/farmacologia , Eritromicina/farmacologia , Feminino , Humanos , Lincosamidas/farmacologia , Dados de Sequência Molecular , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/isolamento & purificaçãoRESUMO
Seven metallo-ß-lactamase-positive isolates of Serratia marcescens were recovered from three patients hospitalized in a neonatal ward in an Argentinean hospital during the period July-September 2011. All the isolates were multidrug-resistant, they belonged to a single clone, and carried a blaVIM-16 -containing class I integron structure. This represents the first nosocomial outbreak of metallo-ß-lactamase in Enterobacteriaceae in Argentina.
Assuntos
Infecção Hospitalar/epidemiologia , Surtos de Doenças , Infecções por Serratia/epidemiologia , Serratia marcescens/enzimologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Argentina/epidemiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Humanos , Recém-Nascido , Masculino , Epidemiologia Molecular , Tipagem Molecular , Infecções por Serratia/microbiologia , Serratia marcescens/isolamento & purificaçãoRESUMO
The objective of the study was to evaluate the susceptibility to old and new antimicrobial agents against hospital-acquired oxacillin-resistant Staphylococcus aureus (HA-ORSA), community-acquired oxacillin-resistant S. aureus (CA-ORSA), and oxacillin-susceptible S. aureus(OSSA). The minimum inhibitory concentration of different antimicrobial agents against 118 S. aureus consecutive and prospective isolates was studied by the CLSI agar dilution method. In ORSA isolates without accompanying resistance, the mecA gene, the Panton-Valentine leukocidin gene (PVL), and the gamma-hemolysin gene were determined by PCR, and the SCC cassette mec gene by multiplex PCR. Out of the 118 isolates, 44 were HA-ORSA, 16 were CA-ORSA, and 58 corresponded to OSSA. The HA-ORSA isolates presented simultaneous resistance to erythromycin, clindamycin, gentamicin, ciprofloxacin, levofloxacin, and moxifloxacin whereas all of them were susceptible to tigecycline (TIG), vancomycin, teicoplanin and linezolid (LZD). The CA-ORSA isolates were only resistant to OXA and presented susceptibility to all the antimicrobial agents assayed. In all of them, the mec-A gene, the PVL gene, the gamma-hemolysin gene and the SCC cassette mec type IV gene were detected. With the OSSA and CA-ORSA isolates, all the non-beta-lactam antimicrobial agents assayed exhibited excellent in vitro activity. However, in the HA-ORSA isolates, only the old antimicrobial agents such as glycopeptides, doxyciclin, rifampin, and trimethoprim-sulfamethoxazole and the new antimicrobial agents LZD and TIG, presented good in vitro activity. The ORSA phenotype without accompanying resistance was highly predictive of CA-ORSA as confirmed by a positive SCC cassette mec type IV.
Assuntos
Anti-Infecciosos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Oxacilina/farmacologia , Resistência às Penicilinas , Estudos ProspectivosRESUMO
From June to December 2004, thirty-three carbapenem-resistant Acinetobacter baumannii isolates recovered from twenty nine patients at the intensive care unit in Hospital de Clínicas, Universidad de Buenos Aires, were studied. The isolates were categorized by molecular methods as: clone I (n = 14), clone IV (n = 7), clone III (n = 6), clone VI (n = 3), clone II (n = 2) and clone X (n = 1). Twenty one isolates were recovered from lower respiratory tract samples, 11 of which belonged to clone I. Clone III isolates were mainly recovered from non-respiratory samples (5/6). Clone IV isolates were recovered from patients not receiving previous imipenem therapy. The majority of the isolates belonging to clones I and IV were able to survive on inert materials for more than 5 days, whereas adhesion to catheters was observed in isolates belonging to clones I and III, especially in those related to bacteremia. Clone III isolates showed colistin, gentamicin and levofloxacin susceptibility, whereas clone I isolates and most from clone IV were only susceptible to colistin and tetracyclines.
Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/isolamento & purificação , Carbapenêmicos/farmacologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/efeitos dos fármacos , Adulto , Argentina/epidemiologia , Aderência Bacteriana , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/microbiologia , Células Clonais/efeitos dos fármacos , Infecção Hospitalar/epidemiologia , Reservatórios de Doenças , Farmacorresistência Bacteriana Múltipla , Contaminação de Equipamentos , Hospitais Universitários , Hospitais Urbanos , Humanos , Unidades de Terapia Intensiva , Pneumonia Bacteriana/epidemiologia , Pneumonia Bacteriana/microbiologia , Respiração Artificial/efeitos adversos , Respiração Artificial/instrumentação , Resistência beta-LactâmicaRESUMO
Entre junio y diciembre de 2004 se estudiaron 33 aislamientos de Acinetobacter baumannii resistentes a los carbapenemes, aislados de materiales clínicos de 29 pacientes internados en la unidad de cuidados intensivos del Hospital de Clínicas de la Universidad de Buenos Aires. La distribución clonal de esos aislamientos fue la siguiente: clon I (n = 14), clon IV (n = 7), clon III (n = 6), clon VI (n = 3), clon II (n = 2) y clon X (n = 1).Veintiún aislamientos se recuperaron de materiales del tracto respiratorio inferior, 11 de ellos pertenecieron al clon I. Casi todos los aislamientos pertenecientes al clon III (5/6) se recuperaron de materiales no respiratorios, y todos los del clon IV se recuperaron de pacientes que no recibieron imipenem. En los aislamientos pertenecientes a los clones I y III se observó una mayor adherencia a catéteres, principalmente en los asociados con bacteriemias. La mayoría de los aislamientos de los clones I y IV sobrevivieron en materiales inertes durante un período superior a los 5 días. La totalidad de los aislamientos del clon III fueron sensibles a colistina, gentamicina y levofloxacina, mientras que los del clon I y la mayoría de los del clon IV sólo fueron sensibles a colistina y tetraciclinas.
From June to December 2004, thirty-three carbapenem-resistant Acinetobacter baumannii isolates recovered from twenty nine patients at the intensive care unit in Hospital de Clínicas, Universidad de Buenos Aires, were studied. The isolates were categorized by molecular methods as: clone I (n = 14), clon IV (n = 7), clone III (n = 6), clone VI (n = 3), clone II (n = 2) and clone X (n = 1). Twenty one isolates were recovered from lower respiratory tract samples, 11 of which belonged to clon I. Clone III isolates were mainly recovered from non-respiratory samples (5/6). Clone IV isolates were recovered from patients not receiving previous imipenem therapy. The majority of the isolates belonging to clones I and IV were able to survive on inert materials for more than 5 days, whereas adhesion to catheters was observed in isolates belonging to clones I and III, especially in those related to bacteremia. Clone III isolates showed colistin, gentamicin and levofloxacin susceptibility, whereas clone I isolates and most from clone IV were only susceptible to colistin and tetracyclines.
Assuntos
Adulto , Humanos , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/isolamento & purificação , Carbapenêmicos/farmacologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/efeitos dos fármacos , Argentina/epidemiologia , Aderência Bacteriana , Resistência beta-Lactâmica , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/microbiologia , Células Clonais/efeitos dos fármacos , Infecção Hospitalar/epidemiologia , Reservatórios de Doenças , Farmacorresistência Bacteriana Múltipla , Contaminação de Equipamentos , Hospitais Universitários , Hospitais Urbanos , Unidades de Terapia Intensiva , Pneumonia Bacteriana/epidemiologia , Pneumonia Bacteriana/microbiologia , Respiração Artificial/efeitos adversos , Respiração Artificial/instrumentaçãoRESUMO
The aim of this study was to conduct a survey regarding the prevalence of trichomoniasis in pregnant patients and to evaluate the utility of different diagnostic methods. Two hundred and twenty three vaginal swab specimens from pregnant women were prospectively examined. Trichomonas vaginalis was investigated by various microscopic examinations, solid culture medium and liquid culture medium. The sensitivity and specificity of microscopy were evaluated by considering both culture media as the "gold standards". The prevalence of T. vaginalis obtained by both culture media (liquid plus solid media) was 4.5% (10/223). The prevalence of T. vaginalis obtained by direct smear, May-Grunwald Giemsa staining, sodium acetate-acetic acid-formalin (SAF)/Methylene blue staining-fixing technique, solid medium and liquid medium was 1.3%, 1.8%, 1.8% and 4.5%, respectively. The sensitivity of the direct smear was 30 %, but for the May-Grunwald Giemsa staining and the SAF/Methylene blue staining-fixing technique was 40%. Considering the three microscopic examinations altogether, the sensitivity rose to 50% and the specificity was 100% for all of them. The solid medium detected only 50% of the positive cases; the liquid medium detected 100%. Due to the low sensitivity obtained with microscopy in asymptomatic pregnant patients, we recommend the use of the liquid medium during pregnancy, in order to provide an early treatment.
Assuntos
Técnicas Bacteriológicas , Complicações Infecciosas na Gravidez/epidemiologia , Vaginite por Trichomonas/epidemiologia , Trichomonas vaginalis/isolamento & purificação , Animais , Argentina/epidemiologia , Corantes , Meios de Cultura , Amarelo de Eosina-(YS) , Feminino , Humanos , Azul de Metileno , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/microbiologia , Prevalência , Estudos Prospectivos , Sensibilidade e Especificidade , Coloração e Rotulagem/métodos , Vaginite por Trichomonas/diagnóstico , Vaginite por Trichomonas/microbiologiaRESUMO
Los objetivos del trabajo fueron conocer la prevalencia de tricomonosis en pacientes embarazadas y evaluar la utilidad de diferentes metodologías para su diagnóstico. Se estudiaron prospectivamente 223 mujeres embarazadas. Trichomonas vaginalis se investigó utilizando distintos exámenes microscópicos, cultivo en medio sólido y medio líquido. Se evaluó la sensibilidad y especificidad de la microscopía considerando a los cultivos en ambos medios como método de referencia. La prevalencia del parásito obtenida por cultivo (medio líquido más medio sólido) fue de 4,5% (10/223) siendo la detección por examen en fresco, coloración de May-Grunwald Giemsa, fresco con solución acética formolada (SAF)/azul de metileno y por cultivo en medio sólido y líquido de 1,3%, 1,8%, 1,8% y 4,5% respectivamente. La sensibilidad del examen en fresco fue 30%, para el May-Grunwald Giemsa y el SAF/azul de metileno fue 40%. Utilizando conjuntamente los tres exámenes microscópicos, la sensibilidad se elevó al 50% y la especificidad fue 100% para todos los exámenes microscópicos. El cultivo en medio líquido detectó el 100% de los casos positivos , mientras que el medio sólido sólo el 50%. Por la baja sensibilidad de la microscopía para T. vaginalis, en embarazadas asintomáticas recomendamos la utilización del cultivo en medio líquido durante el embarazo, para instaurar un tratamiento precoz.
The aim of this study was to conduct a survey regarding the prevalence of trichomoniasis in pregnant patients and to evaluate the utility of different diagnostic methods. Two hundred and twenty three vaginal swab specimens from pregnant women were prospectively examined. Trichomonas vaginalis was investigated by various microscopic examinations, solid culture medium and liquid culture medium. The sensitivity and specificity of microscopy were evaluated by considering both culture media as the "gold standards". The prevalence of T. vaginalis obtained by both culture media (liquid plus solid media) was 4.5% (10/223). The prevalence of T. vaginalis obtained by direct smear, May-Grunwald Giemsa staining, sodium acetate-acetic acid-formalin (SAF)/Methylene blue staining-fixing technique, solid medium and liquid medium was 1.3%, 1.8%, 1.8% and 4.5%, respectively. The sensitivity of the direct smear was 30 %, but for the May- Grunwald Giemsa staining and the SAF/Methylene blue staining-fixing technique was 40%. Considering the three microscopic examinations altogether, the sensitivity rose to 50% and the specificity was 100% for all of them. The solid medium detected only 50% of the positive cases; the liquid medium detected 100%. Due to the low sensitivity obtained with microscopy in asymptomatic pregnant patients, we recommend the use of the liquid medium during pregnancy, in order to provide an early treatment.
Assuntos
Animais , Feminino , Humanos , Gravidez , Técnicas Bacteriológicas , Complicações Infecciosas na Gravidez/epidemiologia , Vaginite por Trichomonas/epidemiologia , Trichomonas vaginalis/isolamento & purificação , Argentina/epidemiologia , Corantes , Meios de Cultura , Amarelo de Eosina-(YS) , Azul de Metileno , Prevalência , Estudos Prospectivos , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/microbiologia , Sensibilidade e Especificidade , Coloração e Rotulagem/métodos , Vaginite por Trichomonas/diagnóstico , Vaginite por Trichomonas/microbiologiaRESUMO
Comparison of different methods in order to identify Proteus spp. The objectives were: (a) to identify Proteus strains to species level, following Farmer's and O'Hara's conventional biochemical reactions; b) to evaluate the sensitivity and specificity of both the API 20E method and a schema of reduced reactions (TSI and MIO agar: motility, indole and ornithine) comparing them with conventional methodology, and c) to evaluate the utility of SDS-PAGE (total proteins) in order to identify Proteus strains to species level. Two hundred and five Proteus spp. clinical isolates, were collected between January 1998 and September 2004, from inpatients and outpatients at Hospital de Clinicas. Strains were identified by means of conventional methodology, the API 20E method, and a schema of reduced reactions. SDS-PAGE (total proteins) was used in 48 out of the 205 strains. The API 20E method identified 79 out of 87 (90.8%) strains of P. mirabilis, 103 out of 103 P. vulgaris complex, and 15 out of 15 P. penneri. Eight strains of P. mirabilis were identified as Proteus spp., the acid production from maltose being necessary to identify them to species level. The schema of reduced reactions identified 205 out of 205 (100%) strains, that is, this schema of reduced reactions identified all the strains to species level without any additional tests, in marked contrast to the API 20E method. The SDS-PAGE (total proteins) identified the three species of the genus, even if the strains of P. mirabilis showed different biochemical reactions.
Assuntos
Proteus/classificação , Proteus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Humanos , Sensibilidade e EspecificidadeRESUMO
The Clinical and Laboratory Standards Institute (CLSI) proposed, beginning in 2004, the use of cefoxitin disks to predict resistance mediated by the mecA gene in all species of coagulase-negative staphylococci (CoNS). The aim of this work was to evaluate the efficiency of the cefoxitin disk and of oxacillin-salt agar screening (MHOX) to characterize the oxacillin resistance mediated by the mecA gene in CoNS. One hundred seven CoNS isolates from different clinical samples were studied. Detection of the mecA gene by PCR was considered the "gold standard." The susceptibility to oxacillin and cefoxitin was detected by the disk diffusion and agar dilution tests, as described by the CLSI. MHOX was also performed with 6 microg/ml of oxacillin and 4% NaCl. The sensitivities of the oxacillin and cefoxitin disks for all CoNS species were 88% and 80%, respectively, whereas the specificities were 63% and 100%, respectively. The sensitivities of the agar dilution test for oxacillin and cefoxitin (for proposed breakpoints of > or =4 microg/ml for resistance and < or =2 microg/ml for susceptibility) were 90% and 85%, respectively, whereas the specificities were 76% and 98%, respectively. MHOX showed a sensitivity of 90% and a specificity of 95% for all CoNS species. Both the MHOX and the cefoxitin disk results indicate that these are appropriate methods for the evaluation of oxacillin resistance mediated by the mecA gene in all CoNS species.
Assuntos
Técnicas de Tipagem Bacteriana/métodos , Cefoxitina/farmacologia , Oxacilina/farmacologia , Resistência às Penicilinas , Proteínas de Ligação às Penicilinas/metabolismo , Staphylococcus/efeitos dos fármacos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Staphylococcus/metabolismoRESUMO
Los objetivos de este trabajo fueron: a) identificar a nivel de especie aislamientos de Proteus siguiendo la combinación de los esquemas de Farmer y O'Hara; b) determinar la utilidad del sistema comercial API 20E y de un esquema reducido de pruebas (agar TSI y agar MIO: movilidad, indol y ornitina), comparar estos procedimientos con la metodología convencional y evaluar su sensibilidad y especificidad, y c) evaluar la utilidad del perfil proteico en la identificación de las distintas especies. Se estudiaron 205 aislamientos de Proteus spp. aislados en el período comprendido entre enero de 1998 y setiembre de 2004, recuperados de distintos materiales clínicos correspondientes a pacientes hospitalizados y ambulatorios atendidos en el Hospital de Clínicas. Los organismos fueron identificados mediante la metodología convencional, por el sistema API 20E y con un esquema reducido de pruebas; 48 de ellos fueron sometidos a un SDS-PAGE. API 20E identificó 79 de 87 aislamientos de P. mirabilis (90,8%), 103/103 del complejo P. vulgaris y 15/15 de P. penneri. Ocho aislamientos identificados como Proteus spp. resultaron ser P. mirabilis, al incluir una prueba adicional (maltosa). En la identificación, el esquema reducido coincidió en un 100% con la metodología convencional. A diferencia del sistema API 20E, el esquema reducido alcanza la correcta identificación de todas las especies en laboratorios de baja complejidad, sin la necesidad de pruebas adicionales. El perfil proteico permitió la correcta diferenciación de las tres especies, independientemente de las diferentes atipias de P. mirabilis.
The objectives were: a) to identify Proteus strains to species level, following Farmer's and O'Hara's conventional biochemical reactions; b) to evaluate the sensitivity and specificity of both the API 20E method and a schema of reduced reactions (TSI and MIO agar: motility, indole and ornithine) comparing them with conventional methodology, and c) to evaluate the utility of SDS-PAGE (total proteins) in order to identify Proteus strains to species level. Two hundred and five Proteus spp. clinical isolates, were collected between January 1998 and September 2004, from inpatients and outpatients at Hospital de Clínicas. Strains were identified by means of conventional methodology, the API 20E method, and a schema of reduced reactions. SDS-PAGE (total proteins) was used in 48 out of the 205 strains. The API 20E method identified 79 out of 87 (90.8%) strains of P. mirabilis, 103 out of 103 P. vulgaris complex, and 15 out of 15 P. penneri. Eight strains of P. mirabilis were identified as Proteus spp., the acid production from maltose being necessary to identify them to species level. The schema of reduced reactions identified 205 out of 205 (100%) strains, that is, this schema of reduced reactions identified all the strains to species level without any additional tests, in marked contrast to the API 20E method. The SDS-PAGE (total proteins) identified the three species of the genus, even if the strains of P. mirabilis showed different biochemical reactions.
Assuntos
Humanos , Proteus/classificação , Proteus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Sensibilidade e EspecificidadeRESUMO
Pregnant women are more susceptible to both vaginal colonization and infection by yeast. Our objectives were to determine the prevalence in pregnant women of yeasts isolated from vaginal exudates and their susceptibility to current antifungal drugs. A total of 493 patients was studied between December 1998 and February 2000. The prevalence of Candida spp. was 28% (Candida albicans 90.4%; Candida glabrata 6.3%; Candida parapsilosis 1.1%, Candida kefyr 1.1 %; unidentified species 1.1 %). The diffusion test in Shadomy agar was employed to determine the susceptibility to fluconazole, ketoconazole, itraconazole and nistatine. All C. albicans, C. kefyr and C. parapsilosis isolates were susceptible in vitro to the antifungal agents tested, while 1 in 6 C. glabrata isolates showed resistance to azole drugs; all strains were susceptible to nistatine. In pregnant women, C. albicans was the yeast most frequently isolated from vaginal exudates; it continues to be highly susceptible to antifungal drugs. Azole resistance was detected only among C. glabrata isolates. Identification to the species level is recommended, specially in cases of treatment failure and recurrent or chronic infection.
Assuntos
Candida/isolamento & purificação , Candidíase Vulvovaginal/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adolescente , Adulto , Antifúngicos/farmacologia , Argentina/epidemiologia , Candida/classificação , Candida/efeitos dos fármacos , Candidíase Vulvovaginal/microbiologia , Farmacorresistência Fúngica , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Prevalência , Especificidade da EspécieRESUMO
The present study was conducted to estimate the prevalence of metallo-beta-lactamases in 91 consecutive carbapenem resistant Pseudomonas aeruginosa isolates, recovered from inpatients at Hospital de Clínicas in Buenos Aires. Both, phenotypic and genotypic methods detected the presence of carbapenemases in 10 (11%) isolates, corresponding to VIM-11 in 7/10 and VIM-2 in the others. Codifying genes were all included in class 1 integrons, upstream genes coding for aminoglycoside modifying enzymes. One hundred percent sensitivity and specificity was achieved by the metallo-beta-lactamases phenotypic screening method using EDTA (1 micromol) disks in the Pseudomonas aeruginosa isolates included in this study. Sensitivity to aztreonam in carbapenem resistant isolates was suspicious of the presence of these enzymes.
Assuntos
Carbapenêmicos/farmacologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/enzimologia , Resistência beta-Lactâmica/genética , beta-Lactamases/análise , Argentina/epidemiologia , Farmacorresistência Bacteriana Múltipla , Genótipo , Hospitais Universitários/estatística & dados numéricos , Humanos , Imipenem/farmacologia , Meropeném , Fenótipo , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Tienamicinas/farmacologia , População Urbana , beta-Lactamases/genéticaRESUMO
La mujer embarazada es más susceptible tanto a la colonización como a la infección vaginal por levaduras. El objetivo de este trabajo fue determinar la prevalencia de levaduras aisladas de exudados vaginales de mujeres embarazadas y evaluar la sensibilidad a los antifúngicos de uso frecuente. Se estudiaron 493 pacientes en el período comprendido desde diciembre de 1998 hasta febrero de 2000. La prevalencia de Candida spp. fue 28% (Candida albicans 90,4%, Candida glabrata 6,3%, Candida parapsilosis 1,1%, Candida kefyr 1,1%, especies no identificadas 1,1%). Se determinó la sensibilidad a fluconazol, ketoconazol, itraconazol y nistatina por el método de difusión en agar Shadomy. Todos los aislamientos de C. albicans, C. kefyr y C. parapsilosis fueron sensibles in vitro a los antifúngicos probados, mientras que 1 de 6 aislamientos de C. glabrata presentó resistencia extendida a todos los azoles, pero sensibilidad a nistatina. En mujeres embarazadas C. albicans fue la levadura más frecuentemente aislada de exudados vaginales y continúa siendo ampliamente sensible a los antifúngicos; sólo en C. glabrata se observó resistencia a los azoles. Se recomienda la identificación de la levadura a nivel de especie particularmente en el caso de falla terapéutica y en infecciones recidivantes o crónicas.
Pregnant women are more susceptible to both vaginal colonization and infection by yeast. Our objectives were to determine the prevalence in pregnant women of yeasts isolated from vaginal exudates and their susceptibility to current antifungal drugs. A total of 493 patients was studied between December 1998 and February 2000. The prevalence of Candida spp. was 28% (Candida albicans 90.4%; Candida glabrata 6.3%; Candida parapsilosis 1.1%, Candida kefyr 1.1%; unidentified species 1.1%). The diffusion test in Shadomy agar was employed to determine the susceptibility to fluconazole, ketoconazole, itraconazole and nistatine. All C. albicans, C. kefyr and C. parapsilosis isolates were susceptible in vitro to the antifungal agents tested, while 1 in 6 C. glabrata isolates showed resistance to azole drugs; all strains were susceptible to nistatine. In pregnant women, C. albicans was the yeast most frequently isolated from vaginal exudates; it continues to be highly susceptible to antifungal drugs. Azole resistance was detected only among C. glabrata isolates. Identification to the species level is recommended, specially in cases of treatment failure and recurrent or chronic infection.
Assuntos
Adolescente , Adulto , Feminino , Humanos , Gravidez , Candida/isolamento & purificação , Candidíase Vulvovaginal/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Antifúngicos/farmacologia , Argentina/epidemiologia , Candida/classificação , Candida/efeitos dos fármacos , Candidíase Vulvovaginal/microbiologia , Farmacorresistência Fúngica , Prevalência , Complicações Infecciosas na Gravidez/microbiologia , Especificidade da EspécieRESUMO
Se estudiaron 91 aislamientos de Pseudomonas aeruginosa resistentes a carbapenemes con el objetivo de conocer la prevalencia de metalo-β-lactamasas y evaluar la habilidad del ensayo de inhibición empleando discos de EDTA (1 µmol) en su detección. Se determinó la presencia de carbapenemasas en 10 (11%) de los aislamientos recuperados. La sensibilidad a aztreonam en los aislamientos resistentes a ambos carbapenemes resultó un buen predictor de la presencia de estas enzimas. Dichas carbapenemasas correspondieron a la enzima VIM-2 en tres de ellos y a VIM-11 en otros siete. En todos los casos los genes codificantes de estas enzimas se encontraron localizados en integrones de clase 1 seguidos corriente abajo de genes codificantes de enzimas acetilantes de antibióticos aminoglucosídicos. El ensayo de detección fenotípica de metalo-β-lactamasas empleando discos de EDTA mostró un 100% de especificidad y sensibilidad en la detección de estas enzimas en la población de Pseudomonas aeruginosa analizadas.
The present study was conducted to estimate the prevalence of metallo-β-lactamases in 91 consecutive carbapenem resistant Pseudomonas aeruginosa isolates, recovered from inpatients at Hospital de Clínicas in Buenos Aires. Both, phenotypic and genotypic methods detected the presence of carbapenemases in 10 (11%) isolates, corresponding to VIM-11 in 7/10 and VIM-2 in the others. Codifying genes were all included in class 1 integrons, upstream genes coding for aminoglycoside modifying enzymes. One hundred percent sensitivity and specificity was achieved by the metallo-β-lactamases phenotypic screening method using EDTA (1 µmol) disks in the Pseudomonas aeruginosa isolates included in this study. Sensitivity to aztreonam in carbapenem resistant isolates was suspicious of the presence of these enzymes.
Assuntos
Humanos , Carbapenêmicos/farmacologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/enzimologia , Resistência beta-Lactâmica/genética , beta-Lactamases/análise , Argentina/epidemiologia , Farmacorresistência Bacteriana Múltipla , Genótipo , Hospitais Universitários/estatística & dados numéricos , Imipenem/farmacologia , Fenótipo , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Tienamicinas/farmacologia , População Urbana , beta-Lactamases/genéticaRESUMO
The ability of the API Coryne system, version 2.0, to identify 178 strains of gram-positive rods was evaluated. Seventy eight isolates belonged to genus Corynebacterium and one hundred to related genera, all strains were isolated from clinical samples at the Laboratory of Bacteriology, Hospital de Clínicas José de San Martin (UBA) between 1995 and 2004. The isolates were identified according to von Graevenitz and Funke's scheme. One hundred and sixty two out of 178 strains (91%) were correctly identified at genus and species level (IC95 = 85.6-94.6), in 44 of them (24.7%) additional tests were needed to final identification. Sixteen strains (9%) were not correctly identified (IC95 = 5.4-14.4); none of the 178 strains remained unidentified. The API Coryne system, version 2.0, is useful to identify the majority of Cory-nebacterium species with clinical relevance: Corynebacterium jeikeium, Corynebacterium urealyticum, Corynebacterium striatum, Corynebacterium pseudodiphtheriticum, Corynebacterium amycolatum and related species such as Arcanobacterium haemolyticum, Dermabacter hominis, Listeria monocytogenes, among others. Nevertheless for yellow-pigmented diphteroid gram-positive rods (Aureobacterium spp., Leifsonia aquatica, Microbacterium spp. and Cellulomonas spp.) and for acid fast gram-positive rods (Rhodococcus, Gordonia, Tsukamurella and Nocardia) the identification usefulness the system is limited.
Assuntos
Técnicas de Tipagem Bacteriana/métodos , Bacilos Gram-Positivos Asporogênicos/classificação , Argentina , Técnicas de Tipagem Bacteriana/instrumentação , Catalase , Corynebacterium/classificação , Corynebacterium/isolamento & purificação , Corynebacterium/metabolismo , Infecções por Corynebacterium/microbiologia , Bacilos Gram-Positivos Asporogênicos/isolamento & purificação , Bacilos Gram-Positivos Asporogênicos/metabolismo , Humanos , Listeria monocytogenes/isolamento & purificação , Listeria monocytogenes/metabolismo , Rhodococcus/classificação , Rhodococcus/isolamento & purificação , Rhodococcus/metabolismo , Especificidade da Espécie , Coloração e RotulagemRESUMO
The aim of this study was to characterize methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered from different infectious sites of hospitalized patients at two university hospitals. Fourteen isolates were analyzed by repetitive sequence based PCR (Rep-PCR), randomly amplified polymorphic DNA assay (RAPD-PCR), and pulsed-field gel electrophoresis (PFGE). We found that a prevalent clone of MRSA, susceptible to rifampin, minocycline, and trimethoprim/sulfamethoxazole (RIF(s), MIN(s), TMS(s)) was present in both hospitals in replacement of the multiresistant MRSA South American clone, previously described in these hospitals. The staphylococcal chromosomal cassette (SCCmec) type I element was detected in this new clone.