RESUMO
To our knowledge, this is the first work on drug susceptibility patterns of rapid growing mycobacteria from Latin America. The susceptibility patterns for 14 antimicrobial agents of the three most important species that cause skin infections in Venezuela were determined as follows: 63 strains belonging to Mycobacterium abscessus group, 66 strains of the Mycobacterium fortuitum group, and 13 Mycobacterium chelonae strains. The M. abscessus group strains were resistant to most antibiotics tested while M. fortuitum strains were relatively susceptible to a large number of antibiotics. We demonstrate the presence of an inducible and truncated erm(41) gene in M. abscessus group, namely M. abscessus subsp. massiliense. We show the variations in susceptibility to antimicrobial agents within and between the mycobacterial species and compare our susceptibility patterns with those reported from other countries. We conclude that the identification of mycobacteria to the species level can guide the antibiotic treatment, but that it is always important to consider drug susceptibility testing when rapidly mycobacteria are isolated.
Assuntos
Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/efeitos dos fármacos , Dermatopatias Bacterianas/epidemiologia , Dermatopatias Bacterianas/microbiologia , Infecções dos Tecidos Moles/epidemiologia , Infecções dos Tecidos Moles/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , Mutação , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Micobactérias não Tuberculosas/genética , Micobactérias não Tuberculosas/isolamento & purificação , Venezuela/epidemiologiaRESUMO
En Venezuela, en junio de 1996, se reportó que los casos de cólera eran causados por V. cholerae O1 serotipo Ogawa. A finales de 1998 se detectó un segundo brote de cólera causado por V. cholerae O1 serotipo Inaba resistente a la ampicilina y el trimetoprim-sulfametoxazol. Para estudiar las relaciones entre las cepas se examinaron veinticinco aislados de Vibrio cholerae O1 obtenidos desde 1996 a 2000 en Venezuela, para determinar la presencia de genes de virulencia y perfiles genómicos. Mediante la reacción en cadena de la polimerasa se determinó la presencia de genes de virulencia. Para determinar el perfil genómico de los aislamientos se utilizó ribotipificación y electroforesis en gel de campo pulsado (PFGE). Todos los aislados resultaron positivos para los genes ctxA, ctxB, zot y ace. El análisis RFLP de los genes RNAr mostró un único patrón de ribotipo V. El análisis de PFGE mostró una similitud de 91,5% independientemente del año o lugar de aislamiento, lo que indica la relación genómica entre los aislados. En conjunto, los datos sugieren que la cepa de V. cholerae O1 resistente a los antibióticos que apareció en 1998 surgió de la cepa epidémica anterior o de otro estrechamente relacionado con el clon anterior, con cambio de serotipo y ganancia de determinantes de resistencia a antibióticos. Es muy importante monitorear continuamente la aparición de la variantes porque mejorará la comprensión de la evolución de nuevos clones de V. cholerae
In Venezuela, cholera reported in June 1996 was caused by V. cholerae O1 serotype Ogawa. Second outbreak of cholera caused by V. cholerae O1 serotype Inaba, resistant to ampicillin and trimethoprim- Sulfamethoxazole, was notify at the end of 1998. Twenty-five isolates of Vibrio cholerae O1 obtained from 1996 to 2000 in Venezuela were examined to study the relationships between strains, presence of virulence genes and genomic profiles. Presence of virulence genes was detected by Polymerase Chain Reaction. Ribotyping and pulsed-field gel electrophoresis (PFGE) were used to determine the genomic profile of isolates. All isolates shown PCR product for ctxA, ctxB, zot and ace genes. RFLP analysis of rRNA gene showed one unique pattern from ribotype V. PFGE analysis revealed a similarity of 91.5%, regardless year or place of isolation, suggesting genomic relatedness among them. Overall, these data suggest that antibiotic resistant V. cholerae O1 El Tor strain that appeared in 1998 emerged from the previous epidemic strain or from another closely related to the previous clone. It is important the continuous monitor the emergence of variants because it will improve our understanding of the evolution of new clones V. cholerae
Assuntos
Humanos , Masculino , Feminino , Vibrio cholerae , Cólera/epidemiologia , Ribotipagem , Tipagem Molecular , Vibrio/química , Saúde Pública , AntibacterianosRESUMO
La tuberculosis es una enfermedad causada por bacterias pertenecientes al Complejo Mycobacterium tuberculosis. El diagnóstico se dificulta por su sintomatología inespecífica y los métodos bacteriológicos que ofrecen resultados tardíos. El objetivo del presente estudio fue comparar el desempeño del sistema automatizado BacT/ALERT® 3D con los métodos convencionales de cultivo en medio Lowenstein-Jensen (L-J) y Ogawa-Kudoh (O-K) para el aislamiento de micobacterias. Se procesaron 266 muestras provenientes de pacientes con sospecha de tuberculosis entre mayo y octubre de 2013. Se aislaron 63 bacilos acido-resistentes: 46 M. tuberculosis y 17 micobacterias no tuberculosas (MNT). Al comparar los tres métodos, se observó que todos presentaron desempeño similar en el aislamiento de M. tuberculosis. Las tasas de recuperación obtenidas no mostraron diferencia estadísticamente significativa (p>0,05) sin embargo, con BacT/ALERT® 3D se aislaron mayor número de MNT, con diferencia significativa respecto al L-J (p<0,05). El tiempo de detección promedio de M. tuberculosis fue de 11 días por BacT/ALERT® 3D, 20 días en L-J y 23 días en O-K. La contaminación cruzada, fue de 0,38%. Se concluyó que BacT/ALERT® 3D es una excelente herramienta para el aislamiento de M. tuberculosis, mejora la recuperación de las MNT y reduce significativamente el tiempo de diagnóstico, lo que permitiría un tratamiento oportuno, con mayor probabilidad de sobrevida del paciente.
Tuberculosis is a disease caused by species of the Mycobacterium tuberculosis complex. The diagnosis is difficult due to nonspecific symptoms and late results of bacteriological culture methods. The aim of this study was to compare the efficiency of the BacT/ALERT® 3D automated system with conventional methods of culture on Lowenstein-Jensen (L-J) and Ogawa-Kudoh (O-K). A total of 266 specimens from patients with clinical suspected tuberculosis were studied from May to October 2013. We recovered, 63 acid fast bacilli isolates: 46 identified as M. tuberculosis and 17 as nontuberculous mycobacteria (NTM). The three methods had a similar performance for isolation of M. tuberculosis; recovery rates obtained showed no statistically significant difference (p> 0.05). However, with the BacT/ALERT® 3D system, a larger number of MNT were isolated, with significant statistic difference for L-J (p <0.05). The average detection time for M. tuberculosis was 11 days with the BacT/ALERT® 3D system, with significant statistic difference for LJ (20.4 days) and O-K (23.2 days). Additionally, cross-contamination was determined as 0.38%. The study results showed that the BacT/ALERT® 3D system is an excellent tool for isolation of M. tuberculosis and it improves the recovery of NTM. Also, the time of diagnosis is significantly reduced, leading to earlier treatment that could improve patient recovery.
RESUMO
Para establecer la sensibilidad de las cepas de Mycobac-terium tuberculosis aisladas en Caracas, entre 2001 y 2006, fueron probadas utilizando el método colorimétrico para determinar las Concentraciones Inhibitorias Mínimas (CIM). De las 324 cepas, 46 (14,2%) mostraron resistencia a una o más drogas. Encontramos resistencia de alto nivel (CIM 8 µg/ml) y bajo nivel (CIM 1-4 µg/ml) a Estreptomicina en 6 (1,8%) y 25 (7,7%) de las cepas, respectivamente. Se encontró resistencia a Isoniacida de bajo nivel (MIC 0,125 - 0,5 µg/ml) en 8 (2,5%) y de alto nivel (MIC 1,0 µg/ml) en 15 (4,6%) de las cepas estudiadas. Hallamos 13 (4,0%) cepas resistentes a Rifampicina (RIF) (5 µg/ml) y 11 (3,4%) a Etambutol (10 µg/ml). De los 17 (5,2%) aislamientos resistentes a dos o más drogas, 12 (3,7%) fueron resistentes a INH y RIF (definido como multirresistencia, MDR). De las 12 cepas MDR, 11 fueron aisladas a partir de esputo y una de líquido pleural. Este estudio muestra un incremento en la prevalencia de la resistencia a las drogas antituberculosas en Caracas, especialmente las cepas MDR. Este aumento apunta hacia la necesidad de una encuesta na-cional, para evaluar el panorama real de la resistencia.
To asses drug susceptibility of Mycobacterium tuberculosis strains isolated from 2001 to 2006 in Caracas. Available strains were tested using colorimetric method to determine the Minimal Inhibitory Concentrations (MIC). Of 324 strains, 46 (14,2%) showed resistance to one or more drugs. High-resistance (8 µg/ml) and low-resistance (1-4 µg/ml) to Strep omycint was found in 6 (1,8%) and 25 (7,7%) strains, respectively. Isoniazid (INH) low-resistance (MIC 0.125 - 0.5 µg/ml) were found in 8 (2,5%) and high-resistant (MIC at 1.0 µg/ml) in 15 (4,6%), Rifampicin resistance (RMP) (5 µg/ml) in 13 (4%), and Ethambutol resistance (10 µg/ml) in 11 (3,4%) of the strains. Of the 17 (5,2%) isolates resistant to two or more drugs, 12 (3,7%) were resistant to INH and RMP (defined as multidrug resistance, MDR). Of these 12 MDR strains, 11 were isolated from sputum and one from pleu ral fluid. This study shows an increased prevalence of resistance to anti-tuberculosis drugs in Caracas, especially the prevalence of MDR strains, raises an urgent need of a proper nationwide survey to evaluate the true picture of resistance.
