Propolis from native Stingless Bees: ultrasound-assisted extraction / Propóleos de abejas nativas sin aguijón: extracción asistida por ultrasonido

BACKGROUND: Propolis has been considered a highly valuable material due to its therapeutic properties. However, in Colombia, the commercialization of propolis is limited not only by low production but also by the little knowledge about its efficient extraction. Therefore, finding an optimal and economical extraction method to obtain propolis is a necessity for beekeepers that would open new possibilities for industrial use and, therefore, for the market. OBJECTIVES:The objective of this study was to evaluate a conventional and ultrasound-assisted extraction method, seeking to obtain the highest yield and a high amount of content of bioactive compounds in propolis extracts. METHODS: The extraction was carried out for three crude propolis from different types of bees: Tetragoniscaangustula or Angelita (ANG), Meliponaeburnea or Melipona(MEL), and Scaptotrigonaspp (SCT). The extracts were characterized by color, pH, visual appearance, solid content, antioxidant capacity, total polyphenol content, and bacterial inhibition capacity. RESULTS: The highest extraction performance was obtained when the ultrasound-assisted method was used, especially for the ANG extract, which in addition to presenting inhibition for gram-negative (E. coli) and gram-positive (S. Aureus) bacteria, had the best antioxidant activity with a value of 545 mg GAE / 100 g of sample and total polyphenol content of 1,884 mg GAE / 100 g of sample. CONCLUSIONS: Ultrasound-assisted extraction can be considered a low-cost alternative to increase the extraction performance of crude propolis, together with its total polyphenol content and antioxidant capacity, without altering its physical properties

ANTECEDENTES: El propóleos ha sido considerado un material de alto valor por sus propiedades terapéuticas. Sin embargo, en Colombia la comercialización de propóleos está limitada no solo por la baja producción sino también por el incipiente conocimiento sobre la extracción eficiente de este. Por ello, encontrar un método de extracción óptimo y económico para la obtención de propóleos es una necesidad para los apicultores que abriría nuevas posibilidades para el uso industrial y por tanto para el mercado. OBJETIVOS: El objetivo de este estudio fue evaluar un método de extracción convencional y asistido por ultrasonido (US) buscando el mayor rendimiento y alto contenido de compuestos bioactivos en extractos de propóleos. MÉTODOS: La extracción se realizó para tres propóleos crudos de diferentes tipos de abejas Tetragonisca angustula o Angelita(ANG), Melipona eburnea o Melipona (MEL) y Scaptotrigona spp (SCT). Todos los extractos se caracterizaron por su color, pH, apariencia visual, contenido de sólidos, capacidad antioxidante, contenido total de polifenoles y capacidad de inhibición bacteriana. RESULTADOS: El mayor rendimiento de extracción se obtuvo cuando se usó el método asistido por ultrasonido y específicamente para el extracto ANG, que además de presentar inhibición para bacterias gram negativas (E. coli) y gram positivas (S. Aureus), tuvo la mejor actividad antioxidante con un valor de 545 mg GAE / 100 g de muestra y contenido total de polifenoles de 1884 mg GAE / 100 g de muestra. CONCLUSIONES: La extracción asistida por ultrasonido puede considerarse una alternativa de bajo costo para aumentar el rendimiento de extracción del propóleos crudo, así como su contenido total de polifenoles y capacidad antioxidante sin alterar sus propiedades físicas

Antibacterial and anti-biofilm potential of Plectranthus amboinicus (Lour) Spreng essential oil and Carvacrol against Staphylococcus aureus and Escherichia coli / Potencial antibacteriano e anti-biofilme do óleo essencial de Plectranthus amboinicus (Lour) Spreng e carvacrol frente a Staphylococcus aureus e Escherichia coli

Introduction: Staphylococcus aureus and Escherichia coli are pathogens that cause chronic infections due to antibiotic resistance mechanisms and their ability to adhere to surfaces and to form biofilms. The search for new agents from natural resources to counter microbial biofilms is an urgent priority in healthcare. Objetive: chemical composition, antibacterial and anti-biofilm activity of Plectranthus amboinicus essential oil (PAEO) and carvacrol were investigated against E. coli and S. aureus. Methodology: PAEO was chemically analyzed using gas chromatography coupled to a mass spectrometer. Antimicrobial activity was assessed by the disc diffusion method and broth microdilution method to determine minimum inhibitory concentrations (MICs). Antibiofilm activity was investigated using 96-well plates with a crystal violet assay. Results: carvacrol (85.25%) was the major component of PAEO. The disc diffusion test confirmed the ability of PAEO and carvacrol in inhibiting bacteria in their planktonic form. The MICs of PAEO against S. aureus and E. coli were 0.31 and 1.25%, respectively, with bactericidal effect. Carvacrol demonstrated a significant antibacterial property (MIC = 0.31%), exhibiting bacteriostatic effects against S. aureus and bactericidal effects against E. coli. Carvacrol considerably inhibited E. coli biofilm formations (58.9%). Moreover, carvacrol inactivated the mature biofilms. Conclusion: the data obtained are promising, and facilitates the development of new therapeutic alternatives. These results indicate the potential of carvacrol in treating diseases caused by E. coli and S. aureus

Introdução: Escherichia coli e Staphylococcus aureus são patógenos que podem causar infecções persistentes devido aos mecanismos de resistência e à sua capacidade de aderir e formar biofilme. A busca por novos agentes a partir de recursos naturais para combater o biofilme é uma prioridade na área da saúde. Objetivo: a composição química, a atividade antibacteriana e anti-biofilme do óleo essencial de Plectranthus amboinicus (PAEO) e do carvacrol foram investigadas frente a S. aureus e E. coli. Metodologia: a análise química do PAEO foi realizada por cromatografia gasosa acoplada a espectrômetro de massa. A atividade antimicrobiana foi avaliada por difusão em disco e microdiluição em caldo para determinar as concentrações inibitórias mínimas (CIMs). As atividades do anti-biofilme foram investigadas usando placas de 96 poços pelo ensaio de cristal violeta. Resultados: o carvacrol (85,25%) foi o principal componente do PAEO. A capacidade do PAEO e do carvacrol para inibir bactérias planctônica foi confirmada por difusão em disco. A CIM do PAEO para S. aureus e E. coli foi de 0,31 e 1,25%, respectivamente, com efeito bactericida. O carvacrol demonstrou uma propriedade antibacteriana significativa (CIM=0,31%), exibindo efeito bacteriostático frente a S. aureus e efeito bactericida para E. coli. O carvacrol inibiu significativamente a formação de biofilme de E. coli (58,9%) e promoveu a desestabilização do biofilme maduro. Conclusão: os dados obtidos são promissores, possibilitando o desenvolvimento de novas alternativas terapêuticas e revelam a potencialidade do carvacrol como fonte para o tratamento de doenças causadas por E. coli e S. aureus.

Antibacterial potential of essential oils against planktonic and sessile cells of Escherichia coli isolated from diarrhea cases in swine / Potencial antibacteriano de aceites esenciales contra células de Escherichia coli planctónicas y sésiles aisladas de diarrea porcina

Escherichia coli is a pathogen associated with infections in piglets in the post-weaning phase, its pathogenicity is related to the animal's susceptibility to bacterial enterotoxins. The objective of the present study was to determine the EOs activity against E. colistrain, in the form planktonic and sessile. Although the Disc-Diffusion tests to determine the Minimum Inhibitory Concentration, do not fully corroborate with the other analyzes of this study, it was noticed bacteria inhibition. The EOs were prepared at 0.4%, 0.8% and 1.0% for tests. The tested EOs were effective against E. coliplanktonic cells (p<0.05). As for the sessile cells, the most significant result was inhibition and 100% sessile cells at the concentration of 1.0% of Cymbopogon citratusEO. Although there was resistance in some treatments, the tested EOs demonstrated inhibition capacity, constituting promising alternatives for the control of E. coli, especially of planktonic cells.

Escherichia coli es un patógeno asociado con infecciones en lechones en la fase posterior al destete, su patogenicidad está relacionada con la susceptibilidad del animal a las enterotoxinas bacterianas. El objetivo del presente estudio fue determinar la actividad de contra E. coli, en la forma planctónico y sésil. Aunque las pruebas de difusión de disco para determinar la concentración inhibitoria mínima, no corroboran completamente con los otros análisis de este estudio, se observó inhibición de la bacteria. Las soluciones basadas en AE se prepararon al 0.4%, 0.8% y 1.0% para pruebas. Los AEs probados fueron efectivos contra las células planctónicas (p<0.05). En cuanto a las células sésiles, el resultado más significativo fue la inhibición y el 100% de las células sésiles a la concentración de 1,0% de Cymbopogon citratus. Aunque hubo resistencia en algunos tratamientos, los AEs probados demostraron capacidad de inhibición, constituyendo alternativas prometedoras para el control de E. coli, especialmente de células planctónicas.

Evaluación de la resistencia a los antibióticos de cepas de Escherichia coli aisladas en carne de cerdo comercializada en los mercados municipales de la ciudad de Guatemala / Evaluation of antibiotics resistance of Escherichia coli strains isolated in pork sold in municipal markets of Guatemala City

La resistencia a los antimicrobianos es un problema de salud pública a nivel mundial que va en aumento y se ve reflejada en la falta de eficacia de los tratamientos de infecciones bacterianas con antibióticos en humanos y en animales. El presente estudio tuvo como objetivo evaluar la resistencia a los antibióticos de cepas de Escherichia coli aisladas en carne de cerdo expendida en los mercados municipales de la ciudad de Guatemala. Se identificaron los antibióticos que presentaron mayor resistencia y mayor sensibilidad in vitro frente a las cepas de E. coli aisladas a partir de 76 muestras de carne de cerdo. Se realizó un muestreo aleatorio simple con afijación proporcional por mercado. Para la identificación de las cepas de E. coli se utilizó la prueba de IMViC y para evaluar la resistencia a los antimicrobianos se utilizó la prueba de Kirby Bauer empleando 9 antibióticos. Se aisló E. coli en el 55% (42/76) de las muestras. La resistencia en las 42 cepas aisladas fue: tetraciclina (83%) neomicina (50%) y sulfametoxasole + trimetoprim (50%). 83% de las cepas (35/42) fueron resistentes a 2 antibióticos y 50% (21/42) a 3 antibióticos o más. Se obtuvo mayor sensibilidad con ceftriaxona (91%), amikacina (83%), gentamicina (65%) y ácido nalidíxico (65%). Se concluye que existe resistencia a los antibióticos evaluados, lo que constituye un riesgo para la salud pública ya que se encuentra en cepas aisladas en un alimento para consumo humano.

Antimicrobial resistance is a global public health threat that is increasing and is reflected in the lack of efficacy of bacterial infection treatments with antibiotics in humans and animals. The objective of this study was to evaluate the resistance to antibiotics of Escherichia coli strains isolated from pork in the municipal markets of Guatemala City. Antibiotics with the highest resistance and those with the highest sensitivity in vitro against the strains of E. coli were evaluated. A simple random sampling was carried out with proportional allocation by market, and 76 samples were collected. IMViC test was used to identify the E. coli strains, and antibiotics resistance was evaluated using the Kirby Bauer with nine different antibiotics. E. coli was isolated in 55% (42/76) of the samples. Resistance was evaluated in the 42 isolates. Antibiotic resistance was detected to tetracycline (83%), neomycin (50%), and sulfamethoxazole + trimethoprim (50%). All isolates presented resistance to at least one antibiotic; it was determined that 83% (35/42) showed resistance to two antibiotics and 50% (21/42) showed resistance to three antibiotics or more. The sensitivity obtained was higher for ceftriaxone (91%), amikacin (83%), gentamicin (65%), and nalidixic acid (65%). In conclusion, antibiotic resistance was detected, which constitutes a risk to public health since it is found in isolated strains in food for human consumption.

In vitro antibacterial activities of silver nanoparticles synthesised using the seed extracts of three varieties of Phoenix dactylifera / Atividades antibacterianas in vitro de nanopartículas de prata sintetizadas usando extratos de sementes de três variedades de Phoenix dactylifera

Green synthesis of silver nanoparticles (AgNPs) is an ecofriendly, cost-effective and promising approach for discovery of novel therapeutics. The aim of the current work was to biogenic synthesize, characterize AgNPs using seed extracts of three economically important varieties of date palm (Iklas, Irziz and Shishi), and assess their anti-pathogenic bacterial activities. AgNPs were synthesised then characterised using electron microscopy and Fourier transform infrared analyses. The bactericidal activities of AgNPs against five different bacterial pathogens, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus and Streptococcus pneumoniae, were determined in vitro. In particular, changes in membrane integrity of virulent bacterial strains in response to AgNPs were investigated. Results of lactate dehydrogenase, alkaline phosphatase activity assays, and measurement of membrane potential revealed that the cytotoxic effects of the AgNPs were mainly centred on the plasma membrane of bacterial cells, leading to loss of its integrity and eventually cell death. In conclusion, green synthesis of AgNPs is an efficient, cost-effective and promising strategy to combat virulent antibiotic-resistant strains.

A síntese verde de nanopartículas de prata (AgNPs) é uma abordagem ecologicamente correta, econômica e promissora para a descoberta de novas terapêuticas. O objetivo do presente trabalho foi sintetizar biogênica, caracterizar AgNPs usando extratos de sementes de três variedades economicamente importantes de tamareira (Iklas, Irziz e Shishi) e avaliar suas atividades bacterianas antipatogênicas. AgNPs foram sintetizados e caracterizados usando microscopia eletrônica e análise de infravermelho por transformada de Fourier. As atividades bactericidas de AgNPs contra cinco diferentes patógenos bacterianos, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Staphylococcus aureus resistente à meticilina e Streptococcus pneumoniae, foram determinadas in vitro. Em particular, foram investigadas alterações na integridade da membrana de cepas bacterianas virulentas em resposta a AgNPs. Os resultados da lactato desidrogenase, dos ensaios da atividade da fosfatase alcalina e da medição do potencial de membrana revelaram que os efeitos citotóxicos dos AgNPs estavam principalmente centrados na membrana plasmática das células bacterianas, levando à perda de sua integridade e, eventualmente, à morte celular. A síntese verde de AgNPs é uma estratégia eficiente, econômica e promissora para combater cepas virulentas resistentes a antibióticos.

Resistencia antibiótica de Escherichia coli y Staphylococcus saprophyticus en la infección urinaria de un hospital público / Antibiotic resistance of Escherichia coli and Staphylococcus saprophyticus in urinary tract infection in a public hospital

La resistencia de antibióticos puede llegar a causar una amplia morbilidad y complicaciones. Objetivo: Determinar el perfil de resistencia antimicrobiana de Escherichia Coli y de Staphylococcus Saprophyticus, en pacientes con infección urinaria hospitalizados en el servicio de Medicina Interna del Hospital Municipal Los Olivos. Métodos: Estudio descriptivo, retrospectivo de corte transversal. Se realizó en el servicio de Medicina Interna del Hospital Municipal los Olivos (HMLO). Participantes: historia clínica de pacientes hospitalizados con infección urinaria en el servicio de Medicina Interna. Intervenciones: Según los criterios de inclusión y exclusión se obtuvieron, 96 historias clínicas (HC) del año 2013. Se utilizó un instrumento de recolección validado. Se realizó el análisis descriptivo con software estadístico STATA versión 25. Resultados: De las 96 HC, la edad promedio fue 55,04 años, los agentes microbianos más frecuentes fueron: la Escherichia coli con 85,3%, Staphylococcus saprophyticus 4.2% y Klebsiella pneumoniae 3,1%. La prevalencia de productores de betalactamasa espectro extendido (BLEE) fue 10,4%. Los antibióticos más resistentes fueron: trimetoprim/sulfametoxazol 89,6%, ampicilina 86%, piperacilina 84,6%, tetraciclina 79,2% y ciprofloxacino 70,8%. Los antibióticos más sensibles fueron: amikacina 100%, imipenem 100%, ertapenem 98%, meropenem 96% y piperacilina/tazobactam 96%. Conclusión: El uropatógeno más frecuente en pacientes con ITU hospitalizados fue la E. coli. Los antibióticos que presentaron resistencia a la E. coli fueron: trimetoprim/sulfametoxazol, ampicilina, piperacilina, tetraciclina y ciprofloxacino, y para el S. Saprophyticus fueron: amoxicilina/ ácido clavulánico, trimetoprim/sulfametoxazol, ceftriaxona y ciprofloxacino(AU)

Resistance to antibiotics may actually cause extensive morbidity and complications. Objective: To determine the antimicrobial resistance profile of Escherichia coli and Staphylococcus saprophyticus, in patients with urinary infection hospitalized in the Internal Medicine service of the Los Olivos Municipal Hospital. Methods: Descriptive, retrospective cross-sectional study. It was carried out in the Internal Medicine service of the Los Olivos Municipal Hospital (HMLO). Participants: clinical history of hospitalized patients with urinary infection in the Internal Medicine service. Interventions: According to the inclusion and exclusion criteria, 96 clinical records (HC) from 2013 were obtained. A validated collection instrument was used. Descriptive analysis was performed with STATA version 25 statistical software. Results: Of the 96 CHs, the average age was 55.04 years, the most frequent microbial agents were: Escherichia Coli with 85.3%, Staphylococcus saprophyticus 4.2% and Klebsiella pneumoniae 3.1%. The prevalence of extended spectrum beta-lactamase producers (ESBL) was 10.4%. The most resistant antibiotics were trimethoprim / sulfamethoxazole 89.6 %, ampicillin 86 %, piperacillin 84.6 %, tetracycline 79.2 % and ciprofloxacin 70.8 %. The most sensitive antibiotics were: amikacin 100%, imipenem 100%, ertapenem 98%, meropenem 96% and piperacillin / tazobactam 96%. Conclusion: The most common uropathogen in hospitalized UTI patients was E. coli. The antibiotics that showed resistance to E. coli were: trimethoprim/sulfamethoxazole, ampicillin, piperacillin, tetracycline, and ciprofloxacin, and for S. saprophyticus they were: amoxicillin/clavulanic acid, trimethoprim / sulfamethoxazole, ceftriaxone and ciprofloxacin(AU)

Hallazgos microbiológicos y susceptibilidad antimicrobiana en cirugía abdominal de urgencia / Microbiological findings and antimicrobial susceptibility in emergency abdominal surgery

Resumen Introducción: Es importante mantener programas de vigilancia bacteriana para disminuir resistencia y definir esquemas farmacológicos adecuados. Los pacientes con abdomen agudo representan un grupo microbiológico especial. Objetivos: Hacer una revisión de agentes patógenos en pacientes adultos operados en nuestro Servicio de Urgencia por patología abdominal con líquido libre y analizar los resultados obtenidos de cultivos respecto a las cepas y la susceptibilidad a los antibióticos. Materiales y Método: Estudio de cohorte prospectiva con estadística descriptiva. Se incluyen pacientes consecutivos, mayores de 18 años, operados por abdomen agudo que presentan líquido libre intraperitoneal entre noviembre de 2017 y abril de 2018. Se excluyen casos con terapia antimicrobiana, hospitalización y/o cirugía en los 3 meses previos. Se registran los cultivos positivos, cepas aisladas, susceptibilidad antimicrobiana, datos demográficos y evolución clínica. Resultados: De 63 pacientes 55% fueron hombres, edad promedio 52,2 años. Las patologías más frecuentes fueron de origen apendicular (62%) y de causa entérica (30%). En un 44% el cultivo fue positivo y en 36% con más de un germen. Escherichia coli fue el patógeno más frecuente (64,2%) seguidos de Enterococcus faecium y Streptococcus anginosus (7,1%). De los otros patógenos cultivados sólo se observó resistencia múltiple en un caso aislado de Morganella Morganii. Conclusiones: Estos datos constituyen la realidad microbiológica local en abdomen agudo. La Escherichia Coli sigue siendo el germen más frecuente, debe enfrentarse con profilaxis y tratamiento antibiótico adecuado. Es necesario mantener vigilancia microbiología local para un manejo acorde.

Introduction: It is important to maintain bacterial surveillance programs to decrease resistance and define adequate pharmacological schemes. Patients with abdomen represent a special microbiological group. Objetives: Make a review of pathogens in adult patients operated in our Emergency Service for abdominal pathology with free fluid and analyze the results obtained from cultures with respect to the strains and susceptibility to antibiotics. Materials and Method: Prospective cohort study with descriptive statistics. We include consecutive patients, older than 18 years old, operated on by abdomen who present free intraperitoneal fluid between November 2017 and April 2018. Cases with antimicrobial therapy, hospitalization and/or surgery 3 months prior are excluded. Positive cultures, isolated strains, antimicrobial susceptibility, demographic data and clinical evolution are recorded. Results: Of 63 patients, 55% were men and the average age was 52.2 years. The most frequent pathologies were of appendicular origin (62%) and of enteric origin (30%). In 44% the crop was positive and in 36% with more than one germ. Escherichia coli was the most frequent pathogen (64.2%) followed by Enterococcus faecium and Streptococcus anginosus (7.1%). Of the others, cultivated pathogens have only observed multiple resistance in an isolated case of Morganella Morganii. Conclusions: These data include the local microbiological reality in acute abdomen. Escherichia coli is still the most frequent germ that must be faced with the profile and the appropriate treatment. It is necessary to maintain local microbiology surveillance for a proper management.

Chemical characterization, antimicrobial and antioxidant activity of sugar-apple (Annona squamosa L. ) pulp extract / Caracterización química, actividad antimicrobiana y antioxidante del extracto de pulpa de manzana de azúcar (Annona squamosa L. )

Synthetic preservatives are widely present in processed foods, but most of them have carcinogenic potential, requiring the development of new natural alternatives such as fruit extracts, for microbial control. The objective of the study was to evaluate the chemical characterization, antioxidant, and antimicrobial activity of the sugar apple pulp (Annona squamosa L.). Physicochemical characteristics were evaluated, an extract was prepared, and its antioxidant activity by DPPH method and antimicrobial by disk diffusion. Minimal inhibitory concentration and minimum bactericidal concentration against strains of Salmonella typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus were evaluated. The physicochemical analysis revealed that sugar apple pulp had 75.0% moisture, 3.0% ash, 4.0% protein, 0.2% lipids, 3.3% fibers, and 14.5% carbohydrates. The antioxidant activity of the extract by the DPPH method was 20.6%. The pulp extract from the sugar apple had inhibition zone for Staphylococcus aureus, satisfactory inhibitory effect against Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, and Salmonella Typhimurium, but did not present a bactericidal effect. Sugar apple pulp presents adequate levels of nutrients and potential for food application due to its microbiological activity and antioxidant properties.

Los conservantes sintéticos están ampliamente presentes en los alimentos procesados, pero la mayoría tienen potencial carcinogénico, lo que requiere el desarrollo de nuevas alternativas naturales para el control microbiano, como los extractos de frutas. El objetivo del estudio fue evaluar la caracterización química, la actividad antioxidante y antimicrobiana de la pulpa de manzana de azúcar (Annona squamosa L.). Se evaluaron las características fisicoquímicas, y se evaluó su actividad antioxidante mediante el método DPPH y antimicrobiano por difusión en disco, concentración inhibitoria mínima y concentración bactericida mínima contra cepas de Salmonella Typhimurium, Escherichia coli, Listeria monocytogenes y Staphylococcus aureus. El análisis fisicoquímico reveló que la pulpa de manzana de azúcar tiene 75.0% de humedad, 3.0% de cenizas, 4.0% de proteínas, 0.2% de lípidos, 3.3% de fibras y 14.5% de carbohidratos. La actividad antioxidante del extracto por el método DPPH fue del 20.6%. El extracto de pulpa de la manzana de azúcar tenía zona de inhibición para Staphylococcus aureus, efecto inhibidor satisfactorio contra Staphylococcus aureus, Escherichia coli, Listeria monocytogenes y Salmonella Typhimurium, pero no presenta efecto bactericida. La pulpa de manzana de azúcar presenta niveles adecuados de nutrientes y potencial para la aplicación de alimentos debido a su actividad microbiológica y propiedades antioxidantes.

Antimicrobial resistance and antibiotic consumption in Mexican hospitals / Resistencia antimicrobiana y consumo de antibióticos en hospitales mexicanos

Abstract: Objective: To establish the current situation of antimicrobial resistance and antibiotic consumption in Mexican hospitals. Materials and methods: Antimicrobial susceptibility data from blood and urine isolates were collected. Defined daily dose (DDD) of antibiotic consumption/100 occupied beds (OBD) was calculated. Results: Study period: 2016 and 2017. Of 4 382 blood isolates, E. coli and K. pneumoniae were most frequently reported, with antimicrobial resistance >30% for most drugs tested, only for carbapenems and amikacin resistance were <20%. A. baumannii had antimicrobial resistance >20% to all drugs. Resistance to oxacillin in S. aureus was 20%. From 12 151 urine isolates, 90% corresponded to E. coli; resistance to ciprofloxacin, cephalosporins and trimethoprim/sulfamethoxazole was >50%, with good susceptibility to nitrofurantoin, amikacin and carbapenems. Global median antimicrobial consumption was 57.2 DDD/100 OB. Conclusions: This report shows a high antimicrobial resistance level in Gram-negative bacilli and provides an insight into the seriousness of the problem of antibiotic consumption.

Resumen: Objetivo: Establecer la situación actual de la resistencia antimicrobiana y el consumo de antibióticos en hospitales mexicanos. Material y métodos:F Se colectaron datos de susceptibilidad antimicrobiana de aislamientos de sangre y orina. Se calculó la dosis diaria definida (DDD) del consumo de antibióticos/100 estancias. Resultados: Periodo de estudio de 2016 a 2017. De 4 382 aislamientos en sangre, E. coli y K. pneumoniae fueron las más frecuentes, con resistencia >30% a la mayoría de las drogas evaluadas; sólo para carbapenémicos y amikacina la resistencia fue <20%. A. baumannii tuvo resistencia >20% a todos los fármacos. La resistencia a oxacilina en S. aureus fue de 20%. De 12 151 aislamientos en urocultivos, 90% correspondió a E. coli; la resistencia a ciprofloxacina, cefalosporinas y trimetoprima/sulfametoxazol fue >50%, con buena susceptibilidad a nitrofurantoína, amikacina y carbapenémicos. La mediana del consumo global de antibióticos en DDD/100 estancias fue de 57.2. Conclusiones: Este reporte muestra el nivel elevado de resistencia en bacilos Gram-negativos y brinda una perspectiva de la gravedad del problema del consumo de antibióticos.

Phylogenetic Group/Subgroups Distributions, Virulence Factors, and Antimicrobial Susceptibility of Escherichia coli Strains from Urinary Tract Infections in Hatay

Abstract INTRODUCTION: Nosocomial and community acquired urinary tract infections (UTIs) are one of the most encountered infections in the world. METHODS: This study aimed to determine the antibiotic susceptibility, phylogeny, and virulence genes of 153 Escherichia coli strains isolated from UTIs. Antimicrobial susceptibility of the isolates to different classes of antimicrobials was determined by the VITEK-2 automated system. Presence of virulence genes and phylogenetic groups were investigated by PCR. RESULTS: Regarding susceptibility to antimicrobials, ampicillin resistance was most abundant (67.3%), followed by amoxicillin-clavulanic acid (50.9%); least abundant was resistance to amikacin (1.3%) and nitrofurantoin (1.3%). Multi drug resistance (MDR) was observed in 34.6% of the isolates, and all isolates were found to be susceptible to imipenem, meropenem and fosfomycine. The majority of the isolates belonged to the phylogenetic group B23 (35.9%), followed by A1 (20.9%), D1 (18.9%), D2 (12.4%), A0 (%5.9), B1 (3.9%) and B2 (1.9%). Among E. coli strains examined, 49% had iucD, 32.7% papE-F, 26.1% papC, 15% cnf2, 11.1% sfa, 7.8% cnf1, 1.3% afaE, 1.3% afaD, 1.3% hlyA, 0.7% f17a-A, 0.7% clpG and 0.7% eaeA genes. CONCLUSIONS Our research demonstrated that virulence factors were distributed among different phylogroup/subgroups, which play a role in UTIs pathogenesis in humans. For this reason, complex and detailed studies are required to determine the relationship between virulence factors and specific E. coli strains that cause UTIs in humans.

Understanding gold toxicity in aerobically-grown Escherichia coli

BACKGROUND: There Is an emerging field to put Into practice new strategies for developing molecules with antimicrobial properties. In this line, several metals and metalloids are currently being used for these purposes, although their cellular effect(s) or target(s) in a particular organism are still unknown. Here we aimed to investigate and analyze Au3+ toxicity through a combination of biochemical and molecular approaches. RESULTS: We found that Au3+ triggers a major oxidative unbalance in Escherichia coli, characterized by decreased intracellular thiol levels, increased superoxide concentration, as well as by an augmented production of the antioxidant enzymes superoxide dismutase and catalase. Because ROS production is, in some cases, associated with metal reduction and the concomitant generation of gold-containing nanostructures (AuNS), this possibility was evaluated in vivo and in vitro. CONCLUSIONS: Au3+ is toxic for E. coli because it triggers an unbalance of the bacterium's oxidative status. This was demonstrated by using oxidative stress dyes and antioxidant chemicals as well as gene reporters, RSH concentrations and AuNS generation.

Antibacterial Activity of Sophorolipids from Candida bombicola Against Human Pathogens

Abstract Sophorolipids are glycolipids that have natural antimicrobial properties and present great potential in the pharmaceutical field. The present study aimed to produce sophorolipids from Candida bombicola using a chicken fat-based medium and evaluate the antimicrobial activity against Gram-negative (Proteus mirabilis, Escherichia coli, Salmonella enterica subsp. enterica) and Gram-positive bacteria (Enterococcus faecium, Staphylococcus aureus and Streptococcus mutans). The production of sophorolipids reached 27.86 g L-1. Based on the structural characterization, 73.55% of the sophorolipids present a mixture of acidic monoacetylated C18:2 and lactonic diacetylated C16:0, and 26.45% were present in the diacetylated C18:1 lactonic form. Bacteria submitted to sophorolipid exposure showed a reduction in viability at doses of 500 μg mL-1 and 2,000 μg mL-1 against Gram-positive and Gram-negative bacteria, respectively. These results suggest that sophorolipids produced in chicken fat medium may be used as antimicrobial agents to prevent or eliminate contamination by different pathogens.

Etiología y perfil de resistencia antimicrobiana en pacientes con infección urinaria adquirida en la comunidad / Etiology and antimicrobial resistance profile in patients with community-acquired urinary infections

Las infecciones del tracto urinario afectan al ser humano a lo largo de su vida y son frecuentes tanto en el ámbito comunitario como en el nosocomial. El objetivo de este estudio fue Identificar los principales agentes etiológicos y el perfil de resistencia a los antibióticos, presentado por los microorganismos más frecuentemente aislados de los urocultivos de pacientes con infección urinaria que acudieron al Laboratorio "Luis Razetti" Mérida -Venezuela, entre enero y junio de 2015. Este estudio fue de tipo observacional, de corte transversal y descriptivo. La población y muestra estuvo conformada por 149 pacientes de ambos sexos, cuyas muestras de orina fueron procesadas utilizado el método del asa calibrada y la identificación bacteriana mediante pruebas bioquímicas convencionales. La susceptibilidad antimicrobiana se determinó a través del método de difusión del disco en agar. Escherichia coli predominó en un 84,6 %, seguido de Proteus mirabilis y Enterococcus faecalis, ambos con (4,7 %). Los porcentajes más altos de resistencia para los aislados de E. coli, se observaron para ampicilina (92,06 %), ampicilina/sulbactam (68,25 %), ácido nalidíxico (38,89 %), ciprofloxacina (38,89 %) y trimetroprim­sulfametoxazol (54,76 %); y presentaron altos niveles de sensibilidad a Nitrofurantoína (80,95 %). El 5,15 % de las cepas de E. coli se mostraron fenotípicamente productoras de belalactamasa de espectro extendido y el 35,29 % de las otras Enterobacteriaceae aisladas, presentaron un perfil fenotípico compatible con la producción de la enzima Inhibitory-resistant TEM (IRT). Es importante destacar que estos estudios permiten conocer la etiología a de infecciones urinarias en la comunidad, así como los perfiles de resistencia y sensibilidad a nivel local, datos relevantes para establecer pautas de tratamiento empírico adaptadas a cada medio.

Urinary tract infections affect the human being throughout his life and are among the most frequent in both the community and nosocomial settings. The Aim of this study was to Identify the main etiological agents and antibiotic resistance profile presented by isolated microorganisms in the urocultures of patients with urinary tract infection who attended the Laboratory "Luis Razetti" Mérida -Venezuela, between January and June 2015. This study was observational, cross-sectional and descriptive. The population and sample consisted of 149 patients of both sexes, whose urine samples were processed using the calibrated handle method and bacterial identification through conventional biochemical tests. The antimicrobial susceptibility is determined through the disk diffusion method in agar. Escherichia coli dominated by 84.6 %, followed by Proteus mirabilis and Enterococcus faecalis, both with (4.7 %). The highest percentages of resistance for E. coli were observed for ampicillin (92.06 %), ampicillin/sulbactam (68.25 %), nalidixic acid (38.89 %), ciprofloxacin (38.89 %) trimetroprim-sulfamethoxazole (54.76 %); and had high levels of sensitivity to Nitrofurantoin (80.95 %). 5.15 % of E. coli strains were phenotypically producing extended-spectrum belalactamase and 35.29 % of others Enterobacteriaceae isolated had a phenotypic profile compatible with the production of the Enzyme Inhibitoryresistant TEM (IRT). It is important to note that these studies allow knowing the etiology of urinary tract infections in the community as well as resistance and sensitivity profiles at the local level, relevant data to establish empirical processing guidelines tailored to each medium.

Resistencia antimicrobiana de cepas comensales de Escherichia coli en niños de dos comunidades rurales peruanas / Antimicrobial resistance of commensal Escherichia coli strains in children of two rural communities in Peru

RESUMEN La resistencia a antibióticos es un problema mundial importante. El objetivo de este estudio fue determinar la resistencia a los antibióticos en cepas comensales aisladas de niños sanos de comunidades rurales de Moyobamba y Urubamba en Perú. Este estudio de cohorte identificó 179 cepas de Escherichia coli comensales provenientes de 93 niños, seguidos durante seis meses. Trece antibióticos fueron analizados mediante disco difusión. Los mayores índices de resistencia fueron para cotrimoxazol (49,1%), ampicilina (48,0%) y ácido nalidíxico (31,8%). Se encontró un aumento en la resistencia del 11,6% para el ácido nalidíxico y del 6,4% para el cotrimoxazol en este periodo. El 34,0% de los aislados fueron multidrogoresistentes. Este estudio respalda hallazgos previos de resistencia a múltiples fármacos en cepas comensales en comunidades rurales, y destaca el aumento en las tasas de resistencia en el tiempo. Recomendamos estudios en poblaciones más grandes, con un seguimiento más prolongado.

ABSTRACT Antibiotic resistance is a major global problem. The objective of this study was to determine antibiotic resistance in commensal strains isolated from healthy children from rural communities of Moyobamba and Urubamba in Peru. This cohort study identified 179 commensal E. coli strains from 93 children, followed for six months. Thirteen antibiotics were analyzed by diffusion disk. The highest rates of resistance were for cotrimoxazole (49.1%), ampicillin (48.0%), and nalidixic acid (31.8%). An 11.6% increase in resistance was found for nalidixic acid and 6.4% for cotrimoxazole in this period; while 34.0% of the isolates were multidrug-resistant. This study supports previous findings of multidrug resistance in commensal strains in rural communities and highlights the increased rates of resistance over time. We recommend studies in larger populations with a longer follow-up.

Análisis clínico y microbiológico de la sepsis grave y el choque séptico por Escherichia coli en Medellín, Colombia / Severe sepsis and septic shock by Escherichia coli, clinical and microbiological analysis in Medellin, Colombia

Resumen Introducción: Escherichia coli es causa frecuente de un amplio espectro de infecciones, desde una infeccion urinaria no complicada hasta la sepsis grave y el choque septico, asociadas con desenlaces de alto impacto como ingreso a UCI y mortalidad. Objetivos: Determinar las diferencias en mortalidad. ingreso a UCI/UCE, presencia de cepas BLEE y tratamiento antimicrobiano en pacientes con sepsis grave y choque séptico por E. coli, con o sin bacteriemia, asi como su variabilidad dependiendo del foco infeccioso. Material y Métodos: Análisis secundario de estudio de cohorte prospective multicéntrico. Resultados: De 458 pacientes que tenian infeccion por E. coli, 123 tenian aislamiento solo en hemocultivo, 222 solo en urocultivo y 113 en ambas muestras. El aislamiento solo en hemocultivo se asocio mayor frecuencia de ingreso a UCI (n = 63; 5,2%). mayor necesidad de ventilacion mecánica (n = 19; 15,5%), mayor mortalidad y estancia hospitalaria (n = 22; 18%; mediana de 12 dias, RIQ= 7-17, respectivamente), pero con menor presencia de cepas productoras de BLEE en comparacion con urocultivos y hemocultivo, urocultivo (n = 20; 17,7% y n = 46; 20,7%, respectivamente). Recibieron tratamiento antimicrobiano en las primeras 24 h 424 pacientes (92,6%), con mas frecuencia piperacilina/ tazobactam (n = 256,60,3%). La proporcion de pacientes tratados empiricamente con carbapenemicos vs no carbapenemicos fue similar en los tres grupos. Discusión: El foco infeccioso. sumado a factores de nesgo para cepas productoras de BLEE, son herramientas utiles para definir pronostico y tratamiento en esta población, debido a la variabilidad clínica y microbiologica en los distintos aislados. Conclusión: Los pacientes con aislamiento de E. coli solo en hemocultivo presentan con mayor frecuencia desenlaces desfavorables en comparación con los pacientes con E. coli en urocultivo, con o sin bacteriemia. Llama la atencion en nuestro medio la menor cantidad de cepas productoras de BLEE en los pacientes con solo hemocultivo positivo.

Background: Escherichia coli is a common cause of a broad spectrum of infections, from non-complicated urinary tract infection, to severe sepsis and septic shock, that are associated to high impact outcomes, such as ICU admission and mortality. Aims: To establish differences in mortality, ICU admission, ESBL positive strains and antibiotic treatment, between patients with E. coli related severe sepsis and septic shock, with or without bacteremia and its variability based on the source of infection. Method: Secondary data analysis of a multicentric prospective cohort study. Results: From 458 patients with E. coli isolation, 123 had E. coli exclusively in blood culture, 222 solely in urine culture, and 113 in both samples. Escherichia coli isolation exclusively in blood culture was associated with higher frequency of ICU admission (n = 63; 51.2%), higher rate of mechanical ventilation requirement (n = 19; 15.5%), higher mortality and longer hospital stay (n = 22; 18%; median of 12 days, IQR= 7 - 17, respectively); but with a lower occurrence of ESBL strains, compared to patients with positive urine culture and positive blood/urine cultures (n = 20; 17.7% and n = 46; 20.7%, respectively). 424 patients (92.6%) received antibiotic treatment in the first 24 hours. The most commonly prescribed was piperacilin/tazobactam (n = 256;60.3%). The proportion of patients empirically treated with carbapenems vs non-carbapenems was similar in the three groups. Discussion: The source of infection, associated with ESBL strains risk factors, are useful tools to define prognosis and treatment in this population, because of their clinical and microbiological variability. Conclusion: Patients with E. coli isolation exclusively in the blood culture had higher frequency of non-favorable outcomes in comparison to patients with E. coli in urine culture with or without bacteremia. Additionally, in our population patients with E. coli solely in blood culture have lower prevalence of ESBL positive strains.

Genetic analysis of the first mcr-1 positive Escherichia coli isolate collected from an outpatient in Chile

ABSTRACT Global dissemination of mcr-like genes represents a serious threat to public health since it jeopardizes the effectiveness of colistin, an antibiotic used as a last-resort treatment against highly antibiotic-resistant bacteria. In 2017, a mcr-1-positive isolate of Escherichia coli was found in Chile for the first time. Herein we report the genetic features of this strain (UCO-457) by whole-genome sequencing (WGS) and conjugation experiments. The UCO-457 strain belonged to ST4204 and carried a 285 kb IncI2-type plasmid containing the mcr-1 gene. Moreover, this plasmid was transferred by conjugation to an E. coli J53 strain at high frequency. The isolate harbored the cma, iroN, and iss virulence genes and did carry resistance genes to trimethoprim/sulfamethoxazole and fluoroquinolones. Other antibiotic resistance determinants such as β-lactamases-encoding genes were not detected, making the isolate highly susceptible to these antibiotics. Our results revealed that such susceptible isolates could be acting as platforms to disseminate plasmid-mediated colistin resistance. Based on this evidence, we consider that mcr-like prevalence deserves urgent attention and should be examined not only in highly resistant bacteria but also in susceptible isolates.

Potencial antimicrobiano do extrato metanólico de Cariniana parvifolia contra patógenos alimentares / Antimicrobial potential of metanolic extract of Cariniana Parvifolia against food pathogens

O presente estudo objetivou avaliar a atividade antimicrobiana do extrato de Cariniana parvifolia contra dois importantes patógenos em alimentos. Para isso, o extrato foi diluído em DMSO nas concentrações 250 mg/mL a 1,95 mg/mL e a atividade antibacteriana foi testada frente as cepas padrões de Escherichia coli ATCC25922 e Staphylococcus aureus ATCC43300por meio da técnica de microdiluição em placa.A concentração inibitória mínima obtida para ambas as cepas foi de 250 mg/mL, enquanto a concentração bactericida mínima foi > 250 mg/mL para S. aureus e 250 mg/mL para E. coli. O extrato metanólico de Cariniana parvifolia apresenta atividade antimicrobiana contra os patógenos S. aureus e E. coli na concentração de 250 mg/mL.

Atividade antimicrobiana da própolis verde frente a bactérias Gram positivas e Gram negativas resistentes a antimicrobianos comerciais / Antimicrobial activity of green propolis against positive Gram bacteria and Gram negative resistant commercial antimicrobials

Este estudo teve por objetivo avaliar a atividade antimicrobiana do extrato da própolis verde frente a cepas Gram positivas e Gram negativas resistentes a antimicrobianos comerciais. Foi realizado teste de suscetibilidade antimicrobiana das cepas de Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa e Listeria monocytogenes frente a oito antimicrobianos comerciais. Posteriormente foi verificado a atividade antimicrobiana da própolis verde com base na concentração inibitória mínima e concentração bactericida apenas para as cepas que se mostraram resistentes. Foi possível verificar, com exceção de E. coli, que as demais bactérias apresentaram resistência a mais de um antimicrobiano, e o extrato de própolis verde apresentou valores de CIM e CBM variando de 0,18 a 6,20 mg.mL-1 e 0,37 a 50,0 mg.mL-1,respectivamente. O extrato da própolis verde apresenta potencial atividade antimicrobiana em substituição ao uso de antimicrobianos sintéticos.

Multidrug resistance and risk factors associated with community-acquired urinary tract infections caused by Escherichia coli in Venezuela / Multirresistencia a medicamentos y factores de riesgo asociados con infecciones urinarias por Escherichia coli adquiridas en la comunidad, Venezuela

Abstract Introduction: The treatment of urinary tract infections has become more challenging due to the increasing frequency of multidrug-resistant Escherichia coli in human populations. Objective: To characterize multidrug-resistant E. coli isolates causing community-acquired urinary tract infections in Cumaná, Venezuela, and associate possible risk factors for infection by extended-spectrum beta-lactamases (ESBL)-producing isolates. Materials and methods: We included all the patients with urinary tract infections attending the urology outpatient consultation and emergency unit in the Hospital de Cumaná, Estado Sucre, Venezuela, from January through June, 2014. blaTEM, blaSHV and blaCTX-M genes detection was carried out by PCR. Results: We found a high prevalence of multidrug-resistant E. coli (25.2%) with 20.4% of the isolates producing ESBL. The ESBL-producing isolates showed a high frequency (66.7%) of simultaneous resistance to trimethoprim-sulphamethoxazole, fluoroquinolones and aminoglycosides compared to non-producing isolates (2.4%). Of the resistant isolates, 65.4% carried the blaTEM gene, 34.6% the blaCTX-M and 23.1% the blaSHV. The blaCTX-M genes detected belonged to the CTX-M-1 and CTX-M-2 groups. Plasmid transfer was demonstrated by in vitro conjugation in 17 of the 26 ESBL-producing isolates. All three genes detected were transferred to the transconjugants. Age over 60 years, complicated urinary tract infections and previous use of a catheter predisposed patients to infection by ESBL-producing E. coli. Conclusions: The high frequency of multidrug-resistant ESBL-producing isolates should alert the regional health authorities to take measures to reduce the risk of outbreaks caused by these types of bacteria in the community.

Resumen Introducción. El tratamiento de las infecciones urinarias constituye un reto creciente por el aumento de Escherichia coli proveniente de la comunidad multirresistente a los medicamentos. Objetivo. Caracterizar aislamientos de E. coli multirresistente causantes de infecciones urinarias adquiridas en la comunidad en Cumaná, Venezuela, y detectar los posibles riesgos de infección por aislamientos productores de betalactamasas de espectro extendido (BLEE). Materiales y métodos. Se incluyeron todos los pacientes atendidos en la consulta externa de urología y en urgencias del Hospital de Cumaná entre enero y junio de 2014 y que evidenciaban infecciones urinarias. La detección de los genes blaTEM, blaSHV y blaCTX-M se hizo mediante la reacción en cadena de la polimerasa (PCR). Resultados. Se encontró una alta prevalencia de E. coli multirresistente a los medicamentos (25,2 %), con 20,4 % de aislamientos productores de BLEE y una gran frecuencia de resistencia simultánea a trimetoprim-sulfametoxazol, fluoroquinolonas y aminoglucósidos (66,7 %) comparados con los no productores (2,4 %). En el 65,4 % de los aislamientos resistentes, se encontró el gen blaTEM; en 34,6 %, el blaCTX-M, y en 23,1 %, el blaSHV. Los genes blaCTX-M detectados pertenecían a los grupos CTX-M-1 y CTX-M-2. Se demostró la transferencia in vitro de plásmidos por conjugación en 17 de los 26 aislamientos productores de BLEE. Los tres tipos de genes detectados se transfirieron a los transconjugantes. La edad mayor de 60 años, las infecciones urinarias con complicaciones y el uso previo de catéter, predispusieron a la infección por cepas de E. coli productoras de BLEE. Conclusiones. La gran frecuencia de aislamientos multirresistentes productores de BLEE debería alertar a las autoridades sanitarias para tomar medidas que reduzcan el riesgo de epidemias causadas por este tipo de bacterias en la comunidad.

Effects of topical azithromycin, moxifloxacin, and povidone iodine on conjunctival bacterial flora in patients undergoing intravitreal injection / Os efeitos da azitromicina tópica, moxifloxacina e iodopovidona na flora bacteriana conjuntival em injeções intravítreas

ABSTRACT Purpose: To compare effects of 5% topical povidone iodine with prophylactic topical azithromycin and moxifloxacin on bacterial flora in patients undergoing intravitreal injection. Methods: A total of 132 patients were randomly assigned to receive treatment with azithromycin or moxifloxacin, or no treatment (control group). In total, 528 specimens were obtained at the time of admission, 4 days before intravitreal injection, 4 days after intravitreal injection, and 8 days after intravitreal injection. Samples were immediately sent to the microbiology laboratory for incubation. Results: The microorganism observed most frequently was coagulasenegative Staphylococcus (23.8%). When the results of samples obtained on Day 4 before injection were assessed, growth of coagulase-negative Staphylococcus was significantly lower in the moxifloxacin group, compared with controls (p=0.049). Acinetobacter baumannii continued to grow after administration of azithromycin (p=0.033). When the results of four days after intravitreal injection were evaluated, growth of coagulase-ne gative Staphylococcus was higher in controls, compared with patients who received azithromycin or moxifloxacin (p=0.004). Eradication rate was significantly higher in the moxifloxacin group than in the control group (p=0.001). Samples obtained on Day 8 after intravitreal injection showed similar levels of bacterial growth in all groups (p=0.217). Conclusion: Moxifloxacin was more effective than 5% povidone iodine in controlling the growth of conjunctival bacterial flora. Use of moxifloxacin in combination with 5% povidone iodine resulted in a synergistic effect.

RESUMO Objetivo: Comparar os efeitos de iodopovidona tópico a 5% com azitromicina e moxifloxacina profiláticas sobre a flora bacteriana em pacientes submetidos à injeção intravítrea. Métodos: Um total de 132 pacientes foram aleatoriamente designados para receber tratamento com azitromicina ou moxifloxacina ou nenhum tratamento (grupo controle). No total, 528 amostras foram obtidas no momento na admissão, 4 dias antes da injeção intravítrea, 4 dias após a injeção intravítrea e 8 dias após a injeção intravítrea. As amostras foram imediatamente enviadas para o laboratório de microbiologia para incubação. Resultados: O microorganismo mais frequentemente observado foi o Staphylococcus coagulase-negativo (23,8%). Quando os resultados das amostras obtidas no dia 4 antes da injeção foram avaliados, o crescimento do Staphylococcus coagulase-negativo foi significativamente menor no grupo mo xifloxacina, em comparação com os controles (p=0,049). Acinetobacter baumannii continuou a crescer após a administração de azitromicina (p=0,033). Quando os resultados de 4 dias após a injeção intravítrea foram avaliados, o crescimento do Staphylococcus coagulase-negativo foi maior no controle, em comparação com pacientes que receberam azitromicina ou moxifloxacina (p=0,004). A taxa de erradicação também foi significativamente maior no grupo moxifloxacina do que no grupo controle (p=0,001). As amostras obtidas no dia 8 após injeção intravítrea mostraram níveis semelhantes de crescimento bacteriano em todos os grupos (p=0,217). Conclusão: A moxifloxacina foi mais eficaz do que 5% de iodopovidona no controle do crescimento da flora bacteriana conjuntival. O uso de moxifloxacina em combinação com 5% de iodopovidona resultou em um efeito sinérgico.