ABSTRACT
Detection of Salmonella spp. isolates showing decreased susceptibility to fluoroquinolones has become important owing to the increasing prevalence of these strains and their association with treatment failure. Nalidixic acid agar dilution, nalidixic acid disk diffusion, MicroScan automated system and real-time polymerase chain reaction (PCR) (LightCycler) followed by melting temperature (Tm) analysis are compared with ciprofloxacin agar dilution as suitable methods to detect decreased susceptibility to fluoroquinolones in 100 Salmonella spp. isolates. Three minor discrepancies were found for nalidixic acid disk diffusion, one minor discrepancy was found for nalidixic acid agar dilution and Tm analysis, and one major discrepancy was found for MicroScan. Nalidixic acid disk diffusion was confirmed as a good screening method. Tm analysis is a rapid and accurate method for detecting decreased susceptibility to fluoroquinolones due to gyrA mutations in Salmonella spp.
Subject(s)
Anti-Bacterial Agents/pharmacology , Fluoroquinolones/pharmacology , Microbial Sensitivity Tests/methods , Polymerase Chain Reaction/methods , Salmonella/drug effects , DNA Gyrase/genetics , DNA, Bacterial/genetics , Drug Resistance, Bacterial/genetics , Humans , Mutation , Salmonella/genetics , Transition TemperatureABSTRACT
The objective of this study was to compare the susceptibility to seven antimicrobials of Acinetobacter baumannii clinical isolates from H. U. de La Princesa of Madrid vs. A. baumannii clinical isolates from Hospital Queen Mary of Hong Kong from January 2004 to March 2005. A total of 74 strains isolated from our hospital and 30 strains attended to Hospital Queen Mary were studied. The MIC (minimal inhibitory concentration) was determined by agar dilution method. NCCLS recommended breakpoints were used against imipenem, tobramycin, amikacin, ofloxacin and ceftazidime. For sulbactam the break point for ampicillin/sulbactam was used. BSAC breakpoint was considered against colistin. Colistin showed the highest susceptibility percentage in Spanish strains (98.64%), followed by imipenem (94.59%) and tobramycin (78.37%). About 50% of the clinical isolates were susceptible to sulbactam (54.05%) and amikacin (51.35%). The majority of the strains were resistant to ofloxacin (2.7% of susceptible strains) and ceftazidime (1.35% of susceptible strains). In the Hong Kong clinical isolates, high susceptibility percentages were shown for most antimicrobials: 96.66% to colistin, sulbactam, tobramycin and amikacin; lower for imipenem (93.33%) and ofloxacin (90%). Ceftazidime presented the lowest susceptibility percentage (10%). In conclusion, higher resistant percentages in Spanish strains than Chinese strains were obtained for most antimicrobials tested. To ofloxacin, 90% of Hong Kong isolates were susceptible while 93% of Madrid isolates were resistant. Geographically remote populations (such as Madrid and Hong Kong) showed important differences according to the susceptibility patterns.
Subject(s)
Acinetobacter Infections/microbiology , Acinetobacter baumannii/drug effects , Drug Resistance, Bacterial , Acinetobacter Infections/epidemiology , Acinetobacter baumannii/isolation & purification , Bacteremia/epidemiology , Bacteremia/microbiology , Body Fluids/microbiology , Drug Resistance, Multiple, Bacterial , Hong Kong/epidemiology , Hospitals, Urban , Humans , Microbial Sensitivity Tests/standards , Spain/epidemiologyABSTRACT
El objetivo de este estudio fue comparar el patrón de sensibilidad a siete antimicrobianos de cepas de Acinetobacter baumannii aisladas en el Hospital Universitario de la Princesa, de Madrid, con el de cepas de A. baumannii aisladas en el Hospital Queen Mary, de Hong Kong, desde enero de 2004 hasta marzo de 2005. Se estudiaron 74 cepas españolas y 30 de Hong Kong. Se determinó la CMI de siete antimicrobianos mediante dilución en agar. Los puntos de corte de las CMI para Acinetobacter spp. fueron los aprobados en 2004 por el NCCLS (para sulbactam, el correspondiente a ampicilina-sulbactam); para la colistina se consideró el punto de corte recomendado por la BSAC. El porcentaje más alto de actividad en las cepas españolas lo presentó colistina (98,64%), seguida de imipenem (94,59%) y de tobramicina (78,37%). Alrededor del 50% de las cepas fueron sensibles a sulbactam (54,05%) y amikacina (51,35%). La mayoría fueron resistentes a ofloxacino (2,7% de cepas sensibles) y ceftazidima (1,35% de cepas sensibles). Las cepas chinas presentaron elevados porcentajes de sensibilidad a la mayoría de los antimicrobianos, siendo de un 96,66% para colistina, sulbactam, tobramicina y amikacina, algo inferior para imipenem (93,33%) y ofloxacino (90%), y sólo a la ceftazidima presentaron baja sensibilidad (10%). En conclusión, se encontraron mayores porcentajes de resistencia en las cepas españolas frente a las de Hong Kong para la mayoría de los antimicrobianos probados. Cabe destacar el ofloxacino, para el cual el porcentaje es prácticamente a la inversa (90% sensibles en Hong Kong y 93% resistentes en Madrid). Los patrones de sensibilidad de A. baumannii presentan importantes diferencias entre lugares tan distantes como Madrid y Hong Kong
The objective of this study was to compare the susceptibility to seven antimicrobials of Acinetobacter baumannii clinical isolates from H. U. de La Princesa of Madrid vs. A. baumannii clinical isolates from Hospital Queen Mary of Hong Kong from January 2004 to March 2005. A total of 74 strains isolated from our hospital and 30 strains attended to Hospital Queen Mary were studied. The MIC (minimal inhibitory concentration) was determined by agar dilution method. NCCLS recommended breakpoints were used against imipenem, tobramycin, amikacin, ofloxacin and ceftazidime. For sulbactam the break point for ampicillin/sulbactam was used. BSAC breakpoint was considered against colistin. Colistin showed the highest susceptibility percentage in Spanish strains (98.64%), followed by imipenem (94.59%) and tobramycin (78.37%). About 50% of the clinical isolates were susceptible to sulbactam (54.05%) and amikacin (51.35%). The majority of the strains were resistant to ofloxacin (2.7% of susceptible strains) and ceftazidime (1.35% of susceptible strains). In the Hong Kong clinical isolates, high susceptibility percentages were shown for most antimicrobials: 96.66% to colistin, sulbactam, tobramycin and amikacin; lower for imipenem (93.33%) and ofloxacin (90%). Ceftazidime presented the lowest susceptibility percentage (10%). In conclusion, higher resistant percentages in Spanish strains than Chinese strains were obtained for most antimicrobials tested. To ofloxacin, 90% of Hong Kong isolates were susceptible while 93% of Madrid isolates were resistant. Geographically remote populations (such as Madrid and Hong Kong) showed important differences according to the susceptibility patterns
Subject(s)
Humans , Acinetobacter Infections/microbiology , Acinetobacter baumannii , Drug Resistance, Bacterial , Spain/epidemiology , Acinetobacter Infections/epidemiology , Acinetobacter baumannii/isolation & purification , Bacteremia/epidemiology , Bacteremia/microbiology , Body Fluids/microbiology , Drug Resistance, Multiple, Bacterial , Hong Kong/epidemiology , Hospitals, Urban , Microbial Sensitivity Tests/standardsABSTRACT
Tuberculosis is considered a serious public health problem. Some factors, such as HIV infection and immigration, have had a major impact on the epidemiology of this illness in Spain. The problem has worsened in recent years due to the dissemination of multiresistant strains. Therefore, a periodic surveillance should be established with respect to the incidence and the resistances observed. In this study we collect M. tuberculosis isolates carried out in the years 2001, 2002, 2003 and 2004, and their susceptibility characteristics in patients from Area 2 in Madrid. To evaluate the isolates' susceptibilities, the MGIT 960 system was used. Of a total of 244 isolates, 15.2% were resistant to at least one antibiotic (different to streptomycin), and 29.9% of the isolates were obtained in samples from immigrant patients. In addition, the immigrant population affected showed a greater percentage of resistances (p <0.01) and a younger mean age (p <0.01) than the indigenous population.
Subject(s)
Drug Resistance, Bacterial , Mycobacterium tuberculosis/drug effects , Adult , Child , HIV Infections/microbiology , Hospitals, Urban , Humans , Middle Aged , Spain , Time Factors , Transients and Migrants , Urban HealthABSTRACT
La tuberculosis es considerada un grave problema de salud pública. Algunos factores, como la infección por VIH o la inmigración, han afectadode manera importante a la epidemiología de esta enfermedad en España. El problema se ha visto agravado en los últimos años con ladiseminación de cepas multirresistentes. Por todo ello debe establecerse una vigilancia periódica respecto a la incidencia y las resistenciasobservadas. En este estudio se recogen los aislamientos de Mycobacterium tuberculosis obtenidos en los años 2001, 2002, 2003 y 2004, ysus características de sensibilidad a los antituberculosos en pacientes del Área 2 de Madrid. Para evaluar la sensibilidad de las cepas se utilizóel sistema MGIT 960®. Se aislaron 244 cepas, de las cuales el 15,2% fue resistente al menos a un antibiótico (distinto de la estreptomicina).Un 29,9% de los aislamientos se obtuvieron en muestras de pacientes inmigrantes. Además, la población inmigrante afectada mostróun mayor porcentaje de resistencias (p <0.01) y una edad media menor (p <0.01) que la población autóctona
Tuberculosis is considered a serious public health problem. Some factors, such as HIV infection and immigration, have had a major impact on theepidemiology of this illness in Spain. The problem has worsened in recent years due to the dissemination of multiresistant strains. Therefore,a periodic surveillance should be established with respect to the incidence and the resistances observed. In this study we collect M. tuberculosisisolates carried out in the years 2001, 2002, 2003 and 2004, and their susceptibility characteristics in patients from Area 2 in Madrid. Toevaluate the isolates susceptibilities, the MGIT 960® system was used. Of a total of 244 isolates, 15.2% were resistant to at least one antibiotic(different to streptomycin), and 29.9% of the isolates were obtained in samples from immigrant patients. In addition, the immigrant populationaffected showed a greater percentage of resistances (p <0.01) and a younger mean age (p <0.01) than the indigenous population
Subject(s)
Humans , Mycobacterium tuberculosis , Drug Resistance, Bacterial , Tuberculosis/drug therapy , Mycobacterium tuberculosis/pathogenicity , Tuberculosis/epidemiology , Epidemiological Monitoring , HIV Infections/complications , Emigration and Immigration/statistics & numerical dataABSTRACT
We present a case of urinary tract infection caused by vancomycin-resistant Enterococcus faecalis. The patient is a 62-year-old woman showing no recent admittances. The isolated microorganism was identified by MicroScan (DADE) and API (BioMerieux) and susceptibility was assessed by disk diffusion, E-test and broth microdilution. The isolate was identified as Enterococcus faecalis and showed high MIC for vancomycin (>128 mg/l) and teicoplanin (8 mg/l) but was susceptible to ampicillin. The transmission routes of vancomycin-resistant enterococci in the community and their clinical implications remain uncertain. Healthy carriers have already been described in several countries but this case report represents an unusual finding.
