Changing Escherichia coli susceptibility and increasing antimicrobial resistance in community urinary tract infections

Introducción: Las infecciones del tracto urinario causadas por bacterias gramnegativas resistentes a los antibióticos son una preocupación creciente debido a las limitadas opciones terapéuticas. Objetivo: Analizar la tendencia de resistencia a los antibióticos en Escherichia coli resistente a la ciprofloxacina aislada de la infección del tracto urinario adquirida en la comunidad. Métodos: Estudio de series de tiempo que analiza registros de urocultivos positivos para E. coli resistente a ciprofloxacina en personas de ≥18 años de 2011 a 2017. Las tendencias en los patrones de resistencia a los antibióticos se obtuvieron mediante la regresión lineal generalizada de Prais-Winsten. El cambio porcentual anual (APC) y el intervalo de confianza del 95 por ciento (IC 95 por ciento) se calcularon a partir del coeficiente de análisis de regresión β1 y el error estándar (SE). Los valores de p < 0,05 se consideraron estadísticamente significativos. Resultados: De los datos analizados, 3363 (26,1 por ciento) fueron positivos para E. coli resistente a la ciprofloxacina. El aumento de E. coli resistente a la ciprofloxacina fue del 45,3 por ciento. Las mujeres sufrieron más infección por E. coli sensible a la ciprofloxacina (75,5 por ciento), pero los hombres tuvieron una mayor probabilidad de infectarse con E. coli resistente a la ciprofloxacina [2,132 (1,891-2,402)]. El aumento de la resistencia fue mayor para la nitrofurantoína (<0,001) y la ceftriaxona (<0,001). La prevalencia de resistencia fue alta para nitrofurantoína, norfloxacina, ácido nalidíxico, amoxicilina/clavulanato, ceftriaxona y tobramicina. A excepción de la gentamicina, que presentó una tendencia a la baja en la resistencia, los otros antimicrobianos analizados no mostraron tendencias en la resistencia a los antibióticos. Conclusiones: Hubo un aumento promedio en la resistencia a los principales antibióticos utilizados para tratar la infecciones del tracto urinario adquirida en la comunidad. Entre los antibióticos probados, solo la gentamicina mostró una tendencia a la baja en la resistencia. Estos resultados son importantes para dirigir la elección de los antimicrobianos para el tratamiento empírico de la infección urinaria adquirida en la comunidad(AU)

Introduction: Urinary tract infections caused by antibiotic-resistant Gram-negative bacteria are a growing concern due to limited therapeutic options. Objective: To analyze the antibiotic resistance trend in ciprofloxacin-resistant Escherichia coli isolated from community-acquired urinary tract infection. Methods: Time series study analyzing records of urine cultures positive for ciprofloxacin-resistant E. coli in persons aged ≥18 years from 2011 to 2017. The trends in antibiotic resistance patterns were obtained using the Prais-Winsten generalized linear regression. Annual percent change (APC) and 95 percent confidence interval (CI 95 percent) were calculated from the regression analysis coefficient β1 and standard error (SE). Values of p<0.05 were considered statistically significant. Results: From the analyzed data, 3 363 (26.1 percent) were positive for ciprofloxacin-resistant E. coli. The increase in ciprofloxacin-resistant E. coli was 45.3 percent. Females suffered more infection by ciprofloxacin-sensitive E. coli (75.5 percent), but males had a higher chance of being infected with ciprofloxacin-resistant E. coli. [2.132 (1.891- 2.402)]. Increase in resistance was highest for nitrofurantoin (<0.001) and ceftriaxone (<0.001). Prevalence of resistance was high for nitrofurantoin, norfloxacin, nalidixic acid, amoxicillin/clavulanate, ceftriaxone, and tobramycin. Except for gentamicin, which presented a downward trend in resistance, the other antimicrobials analyzed displayed no trends in antibiotic resistance. Conclusions: There was an average increase in resistance to the main antibiotics used to treat community-acquired UTI. Among the antibiotics tested, only gentamicin displayed a downward trend in resistance. These results are important to direct the choice of antimicrobials for the empirical treatment of community-acquired UTI(AU)

Extended-spectrum -lactamases producing Klebsiella pneumoniae isolated in two hospitals in Goiânia/Brazil: detection, prevalence, antimicrobial susceptibility and molecular typing

This study was developed to evaluate the prevalence of extended-spectrum -lactamases (ESBL) producing Klebsiella pneumoniae in two hospitals (A and B) in Goiânia, GO, Brazil. The antimicrobial susceptibility of the isolates was determined using the MicroScan WalkAway (Dade Behring, USA). Tests to evaluate the genetic correlation between the isolates were also performed. For the ESBL phenotypic test, the Double-disk diffusion (DD) method was used. The strainsisolated in Hospital B were submitted to DNA analysis by pulsed-field gel electrophoresis (PFGE). The study showed high prevalence of ESBL-producing K. pneumoniae (25% in hospital A and 66.7% in hospital B), with high rates of antimicrobial resistance. The most active compound was imipenem (100% susceptibility in vitro). The PFGE test showed similiarity in five strains and variability in six strains.The high prevalence of ESBL-producing Klebsiella may be due to individual selection and to dissemination of a common strain.

Este estudo foi desenvolvido para avaliar a prevalência de Klebsiella pneumoniae produtoras de ESBLem dois hospitais (A e B) de Goiânia, GO, Brasil. Os isolados foram analisados quanto à resistência a antibióticos através do MicroScan WalkAway (Dade Behring, USA). A correlação genética entre isolados produtores de ESBL também foi avaliada. O teste fenotípico para ESBL foi realizado através de teste de Disco de Difusão Dupla (DD) e a análise do DNA de K. pneumoniae produtoras de ESBL, isoladas no Hospital B, realizada por Pulsed Field Gel Electrophoresis (PFGE). O estudo demonstrou alta prevalência de K. pneumoniae produtora de ESBL (25,0% no hospital A e 66,7% no hospital B) com altas taxas de resistência aos antimicrobianos. O composto mais ativo foi o imipenem (100% de sensibilidade in vitro). O PFGE mostrou similaridade em cinco isolados e variabilidade em seis isolados. A alta prevalência Klebsiella produtora de ESBL pode ser devida à seleção individual e à disseminação de uma cepa comum.