Antiadhesion and antibiofilm potential of Fagonia indica from Cholistan desert against clinical multidrug resistant bacteria / Potencial de antiadesão e antibiofilme de Fagonia indica do deserto do Cholistão contra bactérias multirresistentes clínicas

Abstract High resistance to antimicrobials is associated with biofilm formation responsible for infectious microbes to withstand severe conditions. Therefore, new alternatives are necessary as biofilm inhibitors to control infections. In this study, the antimicrobial and antibiofilm activities of Fagonia indica extracts were evaluated against MDR clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica has antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against multidrug resistant (MDR) clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica had antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against MDR isolates. The maximum inhibitory effects of Fagonia indica chloroform extract on biofilm formation was observed on Staphylococcus aureus (71.84%) followed by Klebsiella pneumoniae (70.83%) after 48 hrs showing that inhibition is also time dependent. Our results about bacterial cell protein leakage indicated that MDR isolates treated with chloroform extract of Fagonia indica showed maximum protein leakage of K. pneumoniae (59.14 µg mL-1) followed by S. aureus (56.7 µg mL-1). Cell attachment assays indicated that chloroform extract resulted in a 43.5-53.5% inhibition of cell adherence to a polystyrene surface. Our results revealed that extracts of Fagonia indica significantly inhibited biofilm formation among MDR clinical isolates, therefore, could be applied as antimicrobial agents and cost effective biofilm inhibitor against these MDR isolates.

Resumo A alta resistência aos antimicrobianos está associada à formação de biofilme responsável por micróbios infecciosos para suportar condições severas. Portanto, novas alternativas são necessárias como inibidores de biofilme para controlar infecções. Neste estudo, as atividades antimicrobiana e antibiofilme dos extratos de Fagonia indica foram avaliadas contra isolados clínicos MDR. O extrato exibiu seu efeito antibiofilme ao alterar a aderência e a desintegração da parede celular bacteriana. Fagonia indica tem efeito antibacteriano com valores de concentração inibitória mínima (CIM) variando de 125 a 500 µg mL-1, e valor de concentração bactericida mínima (MBC) de 500-3000 µg mL-1 contra isolados clínicos multirresistentes (MDR). O extrato exibiu seu efeito antibiofilme ao alterar a aderência e a desintegração da parede celular bacteriana. Fagonia indica teve efeito antibacteriano com valores de concentração inibitória mínima (CIM) variando de 125 a 500 µg mL-1, e concentração bactericida mínima (MBC) de 500-3000 µg mL-1 contra isolados MDR. Os efeitos inibitórios máximos do extrato de clorofórmio Fagonia indica na formação de biofilme foi observada em Staphylococcus aureus (71,84%), seguido por Klebsiella pneumoniae (70,83%) após 48 horas, mostrando que a inibição também é dependente do tempo. Nossos resultados sobre extravasamento de proteínas de células bacterianas indicaram que isolados MDR tratados com extrato clorofórmico de Fagonia indica apresentaram vazamento máximo de proteínas de K. pneumoniae (59,14 µg mL-1), seguido por S. aureus (56,7 µg mL-1). Ensaios de fixação de células indicaram que o extrato de clorofórmio resultou em uma inibição de 43,5-53,5% da aderência das células a uma superfície de poliestireno. Nossos resultados revelaram que extratos de Fagonia indica inibiram significativamente a formação de biofilme entre isolados clínicos MDR, portanto, poderiam ser aplicados como agentes antimicrobianos e inibidores de biofilme de baixo custo contra esses isolados MDR.

Resistencia a fármacos antituberculosos en Cuba, 2015-2017 / Resistance to tuberculosis drugs in Cuba, 2015-2017

Introducción: La tuberculosis persiste como un importante problema de salud mundial. En el 2016 se estimaron 600 000 casos de resistente a rifampicina, y entre estos 490 000 casos multidrogorresistentes. Objetivo: Describir el comportamiento de la resistencia de los aislados de M. tuberculosis de pacientes con tuberculosis pulmonar notificados en Cuba entre los años 2015-2017. Métodos: Se determinó la susceptibilidad a isoniacida y rifampicina mediante el método de la nitratasa. A los aislados resistentes a rifampicina/multidrogorresistentes se les determinó mediante el método proporcional la susceptibilidad a ofloxacina, kanamicina, amikacina y capreomicina. Resultados: El 93,2 por ciento de los aislados fueron sensibles a isoniacida y rifampicina. En 39 se identificó resistencia a isoniacida y 23 fueron resistente a rifampicina. Se identificaron 10 multidrogorresistentes. No se detectó resistencia a fármacos de segunda línea. Conclusiones: Los resultados alertan sobre la necesidad de investigar las causas que han conllevado al incremento de la tuberculosis resistente en Cuba(AU)

Introduction: Tuberculosis continues to be an important health problem worldwide. In the year 2016, as many as 600 000 cases of rifampicin resistance were estimated, among which 490 000 were multi-drug resistant. Objective: Describe the behavior of resistance to M. tuberculosis isolates in patients with pulmonary tuberculosis reported in Cuba in the period 2015-2017. Methods: Susceptibility to isoniazid and rifampicin was determined by the nitratase method. Susceptibility of rifampicin resistant / multi-drug resistant isolates to ofloxacin, kanamycin, amikacin and capreomycin was determined by the proportional method. Results: Of the isolates analyzed, 93.2 percent were sensitive to isoniazid and rifampicin. Isoniazid resistance was identified in 39 and 23 were rifampicin resistant. Ten multi-drug resistant isolates were identified. Resistance to second line drugs was not detected. Conclusions: Results warn about the need to study the factors leading to the increase in resistant tuberculosis in Cuba(AU)

Caracterización de bacilos gramnegativos multi-resistentes, aislados en pacientes hospitalizados en instituciones de salud de Barranquilla (Colombia) / Characterization of multiresistant gram-negative bacilli, isolated in patients hospitalized in health institutions in Barranquilla (Colombia)

Resumen Introducción: La resistencia a carbapenémicos en bacilos gramnegativos es un problema de salud pública mundial, debido a que se asocia con altas tasas de mortalidad, aumento en los niveles de resistencia a otros antimicrobianos, elevación en el potencial de diseminación e incremento en los costos de atención en salud. Objetivo: Caracterizar bacilos gramnegativos multirresistentes, aislados en pacientes hospitalizados en instituciones de salud de Barranquilla (Colombia). Material y Métodos: Estudio descriptivo acerca de la caracterización fenotípica y genotípica de la resistencia bacteriana en las infecciones asociadas a la atención en salud, mediada por carbapenemasas en aislados bacterianos enviados por los laboratorios pertenecientes a la red de laboratorios del Departamento del Atlántico. Resultados: La KPC fue la carbapenemasa más frecuente en las Enterobacterales (27,6%), predominando en Klebsiella pneumoniae (13,1%) sola y asociada a otras carbapenemasas. En Pseudomonas aeruginosa predominó la carbapenemasa VIM (32,8%) y la OXA en Acinetobacter baumannii (17,1%). Conclusión: Se encontró una amplia distribución de cepas multi-resistentes productoras de carbapenemasas en instituciones de salud de Barranquilla, las cuales expresaron los siguientes mecanismos de resistencia: KPC, VIM, NDM, OXA.

Abstract Background: The emergence of carbapenem resistant gramnegative bacilli has become a problem of public health worldwide, because it is associated with high mortality rates, increased levels of resistance to other antimicrobials, increased potential for dissemination transition and increase in health care costs. Aim: To characterize multiresistant gram-negative bacilli, isolated in patients hospitalized in health institutions of Barranquilla (Colombia). Methods: A descriptive study was conducted on the phenotypic and genotypic characterization of bacterial resistance in infections associated with health care, mediated by carbapenemases in bacterial isolates sent by laboratories belonging to the laboratory network of the Department of Atlántico. Results: KPC was the most frequent carbapenemase in Enterobacterales (27.6%), predominantly in Klebsiella pneumoniae (13.1%) alone and associated with other carbapenemases. In Pseudomonas aeruginosa, VIM carbapenemase (32.8%) predominated and OXA in Acinetobacter baumannii (17.1%). Conclusion: A wide distribution of multi-resistant strains producing carbapenemases in Atlantic health institutions was found, which expressed the following resistance mechanisms: KPC, VIM, NDM, OXA.

Clinical outcomes and molecular characterization of drug-resistant tuberculosis in pre- and extensively drug-resistant disease based on line probe assays

ABSTRACT Multidrug-resistant tuberculosis (MDR-TB) represents a significant impact in transmission, outcome, and health costs. The World Health Organization recommends implementation of rapid diagnostic methods for multidrug-resistance detection. This study was performed to evaluate the frequency of pre- and extensively drug resistant tuberculosis (pre-XDR-TB and XDR-TB) among MDR-TB patients, the pattern of resistance mutations for fluoroquinolones and the clinical outcome. Adult patients followed at a Brazilian regional reference center for TB, from January 2013 to June 2019 were included. Stored Mycobacterium tuberculosis (Mtb) cultures were recovered, the DNA was extracted, and the susceptibility test was performed using the line probe assay for second line antimycobacterial drugs, Genotype MTBDRsl version 2.0 (Hain Lifescience, CmbH, Germany). Among 33 MDR-TB included patients, we diagnosed XDR-TB or pre-XDR in five (15%) cases. Of these, mutations related to fluoroquinolones resistance were observed in four Mtb isolates, including one who had no phenotypic resistance profile. In two other patients with phenotypic resistance to ofloxacin, genotypic resistance was not found. Case fatality rate was 60% in pre/XDR-TB group, compared to 3.6% in the remaining of patients. This study observed few cases of pre-XDR and XDR-TB among a MDR-TB cohort. Phenotypic and genotypic assays presented good agreement. Clinical outcome was more favorable for patients with susceptibility to fluoroquinolones and injectable drugs.

Prevalence of antibiotic resistance and virulent factors in nosocomial clinical isolates of Pseudomonas aeruginosa from Panamá

ABSTRACT Background: Pseudomonas aeruginosa is an important causative agent of nosocomial infections. As pathogen, P. aeruginosa is of increasing clinical importance due to its ability to develop high-level multidrug resistance (MDR). Methods: The aim of the present study was to better understand the intrinsic virulence of circulating strains of Pseudomonas aeruginosa, by surveying and characterizing the antibiotic resistance profiles and prevalence of virulence factors in 51 clinical isolates of P. aeruginosa obtained from children admitted to Hospital del Niño-Panamá during the period of October 2016 until March 2017. Antimicrobial susceptibilities were assessed by determining the minimum inhibitory concentration for 12 antibiotics against P. aeruginosa clinical isolates using the VITEK system (https://www.biomerieux.com). Additionally, all isolates were examined by Polymerase Chain Reaction (PCR) for the presence of components of the MexAB-OprM efflux pump system (mexABR) and pyoverdine receptor genes and betalactamases resistance genes (ESBL) using gene-specific primers. Results: A total of 51 pyoverdine producing clinical isolates were analyzed, all of which expressed resistance genes such as genes of the MexAB-OprM efflux pump system (mexABR) and pyoverdine receptor genes (fpvA). Out of 51 MDR isolates, 22 were ESBL producers. The most common ESBL gene was blaTEM expressed by 43% of the isolates. The isolates tested in this study showed increased resistance to antibiotics in the following categories: (i) penicillins (ampicillin (69%), piperacillin (22%); (ii) pyrimethamines (trimethoprim, 65%); (iii) nitrofurans (nitrofurantoin, 63%), and (iv) third-generation cephalosporin cefotaxime (53%). These results underscore a high prevalence of MDR amongst clinical isolates from Panama. Conclusions: The present study indicates that prevalence of BlaTEM-carrying strains is increasing with subsequent multidrug resistance in Panamá and as well reported worldwide. The virulent factors identified in this study provide valuable information regarding the prevalence of resistance genes and their potential impact on treatments that exploit the unique physiology of the pathogen. To prevent further spread of MDR, the proportions of resistant strains of Pseudomonas aeruginosa should be constantly evaluated on healthcare institutions of Panamá. More importantly, this information can be used to better understand the evolution and dissemination of strains hoping to prevent the development of resistance in Pseudomonas aeruginosa. Future studies quantifying the expression of these virulent genes will emphasize on the acquisition of multidrug resistance.

Identification of a predominant genotype of Mycobacterium tuberculosis in Brazilian indigenous population

After nearly a century of vaccination and six decades of drug therapy, tuberculosis (TB) kills more people annually than any other infectious disease. Substantial challenges to disease eradication remain among vulnerable and underserved populations. The Guarani-Kaiowá people are an indigenous population in Paraguay and the Brazilian state of Mato Grosso do Sul. This community, marginalized in Brazilian society, experiences severe poverty. Like other South American indigenous populations, their TB prevalence is high, but the disease has remained largely unstudied in their communities. Herein, Mycobacterium tuberculosis isolates from local clinics were whole genome sequenced, and a population genetic framework was generated. Phylogenetics show M. tuberculosis isolates in the Guarani-Kaiowá people cluster away from selected reference strains, suggesting divergence. Most cluster in a single group, further characterized as M. tuberculosis sublineage 4.3.3. Closer analysis of SNPs showed numerous variants across the genome, including in drug resistance-associated genes, and with many unique changes fixed in each group. We report that local M. tuberculosis strains have acquired unique polymorphisms in the Guarani-Kaiowá people, and drug resistance characterization is urgently needed to inform public health to ensure proper care and avoid further evolution and spread of drug-resistant TB

First report of a blaNDM-resistant gene in a Klebsiella aerogenes clinical isolate from Brazil

Abstract INTRODUCTION: Carbapenemase-resistant enterobacteria that produce the bla NDM gene are found worldwide. However, this is the first report of blaNDM in Klebsiella aerogenes in Brazil. METHODS: The identification of bacterial species was performed using anautomated system and confirmed by biochemical tests, 16S rRNA gene sequencing, and detection of resistance genes. RESULTS: The clinical isolate showed minimum inhibitory concentration resistance to meropenem and polymyxin B at 8mg/L and 4mg/L, respectively. Only the blaNDM gene was detected. CONCLUSIONS: The current report of the blaNDM gene in isolated MDR enterobacteria indicates that this gene can spread silently in a hospital setting.

First report of the aac(6)-Ib-cr gene in Providencia stuartii isolates in Brazil

Abstract INTRODUCTION: The aac(6')-Ib-cr and bla KPC genes are spreading among Enterobacteriaceae species, including Providencia stuartii, in some countries of world. METHODS: These genes were investigated in 28 P. stuartii isolates from a public hospital in Recife, Pernambuco, Brazil, by PCR and sequencing. RESULTS: The aac(6')-Ib-cr gene was detected in 16 resistant isolates, and the bla KPC gene was seen in 14. CONCLUSIONS: The presence of these genes in P. stuartii multi- and extensively drug-resistant isolates indicates that the resistance arsenal of this species is increasing, thus limiting the therapeutic options.

Evaluation of Multidrug Resistant Loop-mediated Isothermal Amplification Assay for Detecting the Drug Resistance of / 生物医学与环境科学（英文）

Objective@#To evaluate multidrug resistant loop-mediated isothermal amplification (MDR-LAMP) assay for the early diagnosis of multidrug-resistant tuberculosis and to compare the mutation patterns associated with the @*Methods@#MDR-LAMP assay was evaluated using 100 @*Results@#The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDR-LAMP were 85.5%, 93.6%, 96.7%, and 74.4% for the detection of resistance to isoniazid and rifampicin, respectively, and 80.5%, 92.3%, 98.6%, and 41.4% for the detection of @*Conclusion@#MDR-LAMP is a rapid and accessible assay for the laboratory identification of rifampicin and isoniazid resistance of

A multidrug-resistant Stenotrophomonas maltophilia clinical isolate from Kamuzu Central Hospital, Malawi

Background Stenotrophomonas maltophilia is a significant opportunistic pathogen that is associated with high mortality in immunocompromised individuals. In this study, we describe a multidrug-resistant (MDR) S. maltophilia clinical isolate from Kamuzu Central Hospital (KCH), Lilongwe, Malawi. Methods: A ceftriaxone and meropenem nonsusceptible isolate (Sm-MW08), recovered in December 2017 at KCH, was referred to theNational Microbiology Reference Laboratory for identification. In April 2018, we identified the isolate using MALDI Biotyper mass spectrometry and determined its antimicrobial susceptibility profile using microdilution methods. Sm-MW08 was analysed by S1-PFGE, PCR, and Sanger sequencing, in order to ascertain the genotypes that were responsible for the isolate`s multidrug-resistance (MDR) phenotype. Results Sm-MW08 was identified as S. maltophilia and exhibited resistance to a range of antibiotics, including all ß-lactams, aminoglycosides (except arbekacin), chloramphenicol, minocycline, fosfomycin and fluoroquinolones, but remained susceptible to colistin and trimethoprim-sulfamethoxazole. The isolate did not harbour any plasmid but did carry chromosomally-encoded blaL1 metallo-ßlactamase and blaL2 ß-lactamase genes; this was consistent with the isolate's resistance profile. No other resistance determinants were detected, suggesting that the MDR phenotype exhibited by Sm-MW08 was innate. Conclusion : Herein, we have described an MDR S. maltophilia from KCH in Malawi, that was resistant to almost all locally available antibiotics. We therefore recommend the practice of effective infection prevention measures to curtail spread of this organism

Infecciones del Tracto Urinario: métodos diagnósticos, tratamiento empírico y multirresistencia en una Unidad de Adultos Área de Emergencias / Urinary Tract Infections: diagnostic methods, empirical treatment and multidrug resistance in an Adult Emergency Area Unit

INTRODUCCIÓN. Las infecciones del tracto urinario por variedad de bacterias uropatógenas multiresistentes se deben al uso de tratamiento empírico o automedicación. OBJETIVO. Describir en las infecciones de tracto urinario los métodos diagnósticos, tratamiento empírico y la multirresistencia. MATERIALES Y MÉTODOS. Estudio observacional, descriptivo, retrospectivo. Población y muestra de 73 Historias Clínicas de pacientes atendidos en la Unidad de Adultos Área de Emergencias del Hospital de Especialidades Carlos Andrade Marín en el período enero a diciembre 2018. Se incluyeron pacientes mayores de 18 años, de ambos sexos, con diagnóstico clínico y por laboratorio de infección del tracto urinario superior e inferior. La información se obtuvo mediante la base de datos AS400, y se procesó en Epi-info y Excel. RESULTADOS. El 71,23% (52; 73) de mujeres tuvieron infección del tracto urinario. Escherichia coli fue frecuente en un 48,39% (15; 31), con mayor resistencia al Clotrimoxazol. El tratamiento empírico con Ciprofloxacino fue utilizado en 27,40% (20; 73). DISCUSIÓN: Se observó controversia en los tipos de estudios de imagen solicitados para el diagnóstico acorde a la clase de infección de tracto urinario así como el tratamiento empírico por factores propios de cada localidad que evitaron resistencia. CONCLUSIÓN. Escherichia coli se aisló de manera frecuente y registró mayor resistencia al Clotrimoxazol; el principal antibiótico prescrito como tratamiento empírico fue la Ciprofloxacina; el examen más solicitado fue la Urotomografía.

INTRODUCTION. Urinary tract infections due to a variety of multi-resistant uropathogenic bacteria are due to the use of empirical treatment or self-medication. OBJECTIVE. Describe diagnostic methods, empirical treatment and multidrug resistance in urinary tract infections. MATERIALS AND METHODS. Observational, descriptive, retrospective study. Population and sample of 73 Medical Records of patients treated in the Emergency Area Adult Unit of the Carlos Andrade Marín Specialty Hospital in the period january to december 2018. Patients older than 18 years of age, of both sexes, with clinical diagnosis and due to upper and lower urinary tract infection laboratory. The information was obtained through the AS400 database, and was processed in Epi-info and Excel. RESULTS. 71,23% (52; 73) of women had urinary tract infection. Escherichia coli was frequent in 48,39% (15; 31), with greater resistance to Clotrimoxazole. Empirical treatment with Ciprofloxacin was used in 27,40% (20; 73). DISCUSSION: Controversy was observed in the types of imaging studies requested for diagnosis according to the class of urinary tract infection as well as the empirical treatment due to factors specific to each locality that prevented resistance. CONCLUSION. Escherichia coli was frequently isolated and showed greater resistance to Clotrimoxazole; the main antibiotic prescribed as empirical treatment was Ciprofloxacin; the most requested examination was the Urotomography.

Antimicrobial resistance evaluation of bacteria isolated from infections in small animals in the Umuarama region, Paraná / Avaliação da resistência antimicrobiana de bactérias isoladas de infecções em pequenos animais na região de Umuarama, Paraná

Bacterial resistance is shown to be an inevitable side effect due to the excessive use of antibiotics, becoming a significant concern worldwide. Knowledge of regional bacterial resistance profiles enables the development of site-specific infection control practices, making conscious and moderate use of commercially available antibiotics. The aim of this study was the retrospective evaluation of the antimicrobial resistance profile of bacteria isolated from companion animal infections in the region of Umuarama/PR, from 2013 to 2017. This research was performed by analyzing the database belonging to the "Laboratório de Microbiologia Animal" at the "Universidade Estadual de Maringá" (UEM). Staphylococcus spp. represented 45.53% of the bacteria isolated from clinical infections in small animals in the period and place evaluated, followed by enterobacteria (34.04%), non-fermenting Gram-negative bacilli (NFGNB, 11.06%) and Streptococcus/Enterococcus (9.36%). A high number of antimicrobial resistance to antibiotics used in veterinary medicine was found. The lowest resistances associated with the best impact factor values were found for aminoglycosides, especially amikacin, chloramphenicol, and fluoroquinolones (norfloxacin and ciprofloxacin). Intermediate results were found for sulbactam-associated ampicillin, ceftriaxone, amoxicillin-clavulanic acid, and enrofloxacin. According to the number of resistant antimicrobial drugs, 64.26% (151/235) of the isolates were classified as multidrug-resistant, being 15.32% extensively resistant. Considering the resistance to antimicrobial classes, 68.94% (162/235) of the isolates were classified as multiresistant, being 19.15% extensively resistant. No bacterial strains were characterized as pan-resistant, but ten bacteria were resistant to all classes tested, with isolated susceptibility to certain drugs. Through the evaluation of resistance profiles found in the period and place studied and relevant literature, it is clear that there is a growing increase in the number of multiresistant bacteria among domestic animals which characterizes a serious risk to public health. The therapeutic arsenal is becoming increasingly diminished, and there is more difficulty in empirical drug selection, making antimicrobial susceptibility testing essential for more specific selection in antimicrobial therapy. Educational measures on the conscious use of antibiotics, infection control, and prevention of local specific zoonoses need to be instituted for the knowledge of health professionals and general access of the population.(AU)

A resistência bacteriana, mostra-se como um efeito colateral inevitável pelo excessivo uso de antibióticos, tornando-se alvo de grande preocupação mundial. O conhecimento dos perfis de resistência bacteriana regionais possibilita o desenvolvimento de práticas de controle de infecções específicas para cada localidade, fazendo uso consciente e moderado dos antibióticos disponíveis no mercado. O objetivo deste estudo foi a avaliação retrospectiva do perfil de resistência antimicrobiana de bactérias isoladas de infecções de animais de companhia na região de Umuarama/PR, no período de 2013 a 2017. Esta pesquisa foi realizada por meio da análise do banco de dados pertencente ao Laboratório de Microbiologia Animal da Universidade Estadual de Maringá (UEM). Os Staphylococcus spp. representaram 45,53% das bactérias isoladas de infecções clínicas em pequenos animais no período e local avaliado, seguido por enterobactérias (34,04%), bacilos Gram-negativos não fermentados (BGNNF, 11,06%) e Streptococcus/Enterococcus (9,36%). Um número elevado de resistência antimicrobiana frente aos antibióticos utilizados na medicina veterinária foi encontrado. As menores resistências associadas aos melhores valores do fator de impacto foram encontrados para aminoglicosídeos, em especial amicacina, cloranfenicol, fluoroquinolonas (norfloxacina e ciprofloxacina). Já resultados intermediários foram encontrados para ampicilina associada a sulbactam, ceftriaxona, amoxacilina com ácido clavulônico e enrofloxacina. Conforme o número de drogas antimicrobianas resistentes, foram classificados como multirresistentes 64,26% (151/235) dos isolados, sendo 15.32% extensivamente resistentes. Já considerando a resistência a classes de antimicrobianos, 68,94% (162/235) dos isolados foram classificados como multirresistentes, sendo 19.15% extensivamente resistentes. Nenhum isolado bacteriano foi caracterizado como pan-resistente, porém 10 bactérias foram resistentes a todas as classes testadas, com susceptibilidade isolada a determinadas drogas. Por meio da avaliação dos perfis de resistência encontrados no período e local estudados e de literatura pertinente, percebe-se que há um aumento crescente no número de bactérias multirresistentes entre os animais domésticos o que caracteriza um grave risco à saúde pública. O arsenal terapêutico está se tornando cada vez mais diminuto e há mais dificuldade na seleção empírica de drogas, tornando essencial a realização de testes de susceptibilidade antimicrobiana para uma seleção mais específica na terapêutica antimicrobiana. Medidas educativas sobre o uso consciente dos antibióticos, controle de infecções e prevenção de zoonoses específicas para as localidades precisam ser instituídas para conhecimento dos profissionais do setor da saúde e acesso geral da população.(AU)

Patrones de resistencia a los antimicrobianos en serovares de Salmonella enterica en Perú, 2012-2015 / Patterns of resistance to antimicrobials in serovars of Salmonella enterica in Peru, 2012-2015

Resumen Introducción: La salmonelosis es una zoonosis universal, causante de frecuentes brotes de enfermedades transmitidas por alimentos; Salmonella enterica es la especie con la mayor prevalencia, describiéndose un aumento progresivo de su resistencia a antimicrobianos. Objetivo: Determinar la frecuencia de serotipos y los patrones de resistencia antimicrobiana en aislados de S. enterica remitidos al Instituto Nacional de Salud, Lima, Perú. Materiales y Métodos: Se realizó un estudio descriptivo, transversal. Se incluyeron en el estudio todas las cepas remitidas como parte de la vigilancia nacional basada en laboratorio entre los años 2012 y 2015. Las cepas fueron confirmadas mediante pruebas convencionales y serotipificadas por el esquema de Kauffmann-White; la susceptibilidad antimicrobiana y la confirmación del fenotipo BLEE se realizó según el método de Kirby-Bauer y método de Jarlier. Resultados: Un total de 540 cepas de S. enterica fueron incluidos en el estudio, de las que 96% (520/540) correspondió a cepas de origen humano y 4% (20/540) de origen no humano (aves, alimentos y ambiental). En muestras humanas, el serovar más frecuente fue S. Infantis (57%), seguido de S. Enteritidis (27%) y S. Typhimurium (6%). Se encontró una alta resistencia a nitrofurantoína (74%), ácido nalidíxico (64%), ciprofloxacina (63%), tetraciclina (63%), ampicilina (56%), cotrimoxazol (56%), cefotaxima (53%) y cloranfenicol (50%). En muestras no humanas, el serotipo más frecuente fue S. Infantis (45%), seguido de S. Typhimurium (40%) y S. Enteritidis (10%). encontrándose una alta resistencia a ciprofloxacina (45%), cotrimoxazol (40%), y tetraciclina (40%). El 65% del total de las cepas presentó resistencia a más de dos antimicrobianos, 43,3% fueron productoras de BLEE y 99% de éstas presentaron resistencia a entre seis y ocho antimicrobianos. Conclusiones: Se encontró una alta frecuencia de Salmonella Infantis productoras de BLEE, con multi-resistencia a los antimicrobianos en los aislados de muestras humanas y no humanas recibidas en el Instituto Nacional de Salud.

Abstract Background: Salmonellosis is a universal zoonosis, causing frequent outbreaks of foodborne illness; Salmonella enterica is the species with the highest prevalence, a progressive increase in its resistance to antimicrobials is described. Aim: To determine the frequency of serovars and antimicrobial resistance patterns in S. enterica isolates submitted to the National Institute of Health, Lima, Peru. Methods: This is a cross-sectional study. All strains referred as part of national laboratory-based surveillance between 2012 and 2015 were included in the study. Strains were confirmed by conventional tests and serotyped by the Kauffmann-White scheme; antimicrobial susceptibility and confirmation of the BLEE phenotype was performed according to the method of Kirby-Bauer and Jarlier's method. Results: A total of 540 strains of S. enterica were included in the study, where 96% (520/540) corresponded to human strains and 4% (20/540) to non-human strains (birds, food and environmental). In human samples, the most frequent serovar was S. Infantis (57%), followed by S. Enteritidis (27%) and S. Typhimurium (6%). High resistance to nitrofurantoin (74%), nalidixic acid (64%), ciprofloxacin (63%), tetracycline (63%), ampicillin (56%), sulfamethoxazole-trimethoprim (56%), cefotaxime (53%) and chloramphenicol (50%) was detected. In non-human samples, the most frequent serotype was S. Infantis (45%), followed by S. Typhimurium (40%) and S. Enteritidis (10%); a high resistance to nalidixic acid (55%), ciprofloxacin (45%), sulfamethoxazole-trimethoprim (40%), nitrofurantoin (40%), tetracycline (40%) was found. 65% of all strains had resistance to more than two antibiotics, 43,3% were ESBL producers and 99% of these had resistance between six and eight antibiotics. Conclusions: We found a high frequency of S. Infantis producing ESBL with multi-resistance to the antimicrobials in human and nonhuman samples received by the National Institute of Health.

Multidrug-resistant Escherichia coli isolated from a dog with a history of urolithiasis: case report / Escherichia coli multirresistente isolada de cão com histórico de urolitíase: relato de caso

Bacterial resistance is a reality in both human and veterinary health, it limits the therapeutic arsenal and raises the costs of the patient's treatment. A dog with signs of cystitis received treatment with 5mg/kg enrofloxacin at three consecutive times, with low effectiveness. The presence of urethral uroliths was identified and urohydropulsion was done. The animal presented a new obstruction, for which a cystotomy was performed, but continued with signs of infection. Uroculture and antimicrobial susceptibility test were then performed. Escherichia coli was identified, which was resistant to 13 antibiotics, being sensitive only to piperacillin-tazobactam and amikacin. In the screening test for ß-lactamase, the production of ESßL was detected. The qPCR indicated the presence of the bla CTXm, bla DHA, bla OXA, bla IMP, bla TEM, bla GIM, bla SIM, bla SPM and bla SME genes, which may lead to a phenotypic resistance profile for ampicillin, amoxicillin-clavulanate, aztreonam, cefepime cefoxitin, cefuroxime, ceftazidime, ceftriaxone, imipenem, and piperacillin-tazobactam. This case reaffirms the value that laboratory analysis adds to the diagnosis and treatment of cystitis and urolithiasis, which can define the direction of evolution of the prognosis and the speed at which the patient's health will be restored.(AU)

A resistência bacteriana aos antibióticos é uma realidade, tanto na saúde humana quanto veterinária, limita o arsenal terapêutico e eleva os custos relacionados ao tratamento do paciente. Um cão, com sinais de cistite, recebeu tratamento com enrofloxacina, na dose de 5mg/kg, em três momentos seguidos, com baixa efetividade. Identificou-se presença de urólitos uretrais e foi feita uro-hidropropulsão. O animal apresentou nova obstrução, para a qual foi realizada uma cistotomia, mas continuou com sinais de infecção. Realizou-se, então, urocultura e teste de antibiograma. Foi identificada Escherichia coli, que se mostrou resistente a 13 antibióticos, sendo sensível somente à piperacilina-tazobactam e amicacina. No teste de triagem para ß-lactamase, detectou-se a produção de ESßL. A qPCR indicou presença dos genes blaCTXm, blaDHA, blaOXA, blaIMP, blaTEM, blaGIM, blaSIM, blaSPM e blaSME, que podem conduzir um perfil fenotípico de resistência para ampicilina, amoxicilina-ácido clavulânico, aztreonam, cefepima, cefoxitina, cefuroxima, ceftazidima, ceftriaxona, imipenem, piperacilina-tazobactam. Este caso reafirma o valor que a análise laboratorial agrega ao diagnóstico e tratamento da cistite e da urolitíase, podendo definir o sentido de evolução do prognóstico e a velocidade em que a saúde do paciente será restabelecia.(AU)

Proposal of a clinical score to stratify the risk of multidrug-resistant gram-negative rods bacteremia in cancer patients

ABSTRACT Introduction: Multidrug-resistant gram-negative rods (MDR GNR) represent a growing threat for patients with cancer. Our objective was to determine the characteristics of and risk factors for MDR GNR bacteremia in patients with cancer and to develop a clinical score to predict MDR GNR bacteremia. Material and Methods: Multicenter prospective study analyzing initial episodes of MDR GNR bacteremia. Risk factors were evaluated using a multiple logistic regression (forward-stepwise selection) analysis including variables with a p < 0.10 in univariate analysis. Results: 394 episodes of GNR bacteremia were included, with 168 (42.6 %) being MDR GNR. Five variables were identified as independent risk factors: recent antibiotic use (OR = 2.8, 95 % CI 1.7-4.6, p = 0.001), recent intensive care unit admission (OR = 2.9, 95 % CI 1.1-7.8, p = 0.027), hospitalization ≥ 7 days prior to the episode of bacteremia (OR = 3.5, 95 % CI 2-6.2, p = 0.005), severe mucositis (OR = 5.3, 95 % CI 1.8-15.6, p = 0.002), and recent or previous colonization/infection with MDR GNR (OR = 2.3, 95 % CI 1.2-4.3, p = 0.028). Using a cut-off value of two points, the score had a sensitivity of 66.07 % (95 % CI 58.4-73.2 %), a specificity of 77.8 % (95 % CI 71.4-82.7 %), a positive predictive value of 68 % (95 % CI 61.9-73.4 %), and a negative predictive value of 75.9 % (95 % CI 71.6-79.7 %). The overall performance of the score was satisfactory (AUROC 0.78; 95 % CI 0.73-0.82). In the cases with one or none of the risk factors identified, the negative likelihood ratio was 0.18 and the post-test probability of having MDR GNR was 11.68 %. Conclusions: With the growing incidence of MDR GNR as etiologic agents of bacteremia in cancer patients, the development of this score could be a potential tool for clinicians.

Evaluación de la elución de sensidiscos para la determinación de susceptibilidad a colistín en bacilos gramnegativos multi-resistentes / Evaluation of sensi-disk elution for colistin susceptibility determination in multidrug resistant gramnegative bacilli

Resumen Utilizando cepas clínicas de bacilos gramnegativos multi-resistentes (MDR), comparamos las CIM obtenidas de la microdilución en caldo, el método de referencia y el método de elución de sensidiscos. Encontramos que, con la excepción de A. baumannii, los resultados fueron muy similares. El método de elución de sensidiscos podría ser una buena alternativa y confiable para la determinación de la resistencia a colistín.

Abstract Using clinical strains of multidrug resistant (MDR) Gram negative bacilli, we compared MICs obtained from both broth microdilution, the reference method, and sensi-disk elution method. We found that, with A. baumannii exception, results were very similar. Sensi-disk elution method could be a good and reliable alternative for colistin resistance determination.

Evaluation of drug susceptibility profile of Mycobacterium tuberculosis Lineage 1 from Brazil based on whole genome sequencing and phenotypic methods

BACKGROUND The evaluation of procedures for drug susceptibility prediction of Mycobacterium tuberculosis based on genomic data against the conventional reference method test based on culture is realistic considering the scenario of growing number of tools proposals based on whole-genome sequences (WGS). OBJECTIVES This study aimed to evaluate drug susceptibility testing (DST) outcome based on WGS tools and the phenotypic methods performed on isolates of M. tuberculosis Lineage 1 from the state of Pará, Brazil, generally associated with low levels of drug resistance. METHODOLOGY Culture based DST was performed using the Proportion Method in Löwenstein-Jensen medium on 71 isolates that had been submitted to WGS. We analysed the seven main genome sequence-based tools for resistance and lineage prediction applied to M. tuberculosis and for comparison evaluation we have used the Kappa concordance test. FINDINGS When comparing the WGS-based tools against the DST, we observed the highest level of agreement using TB-profiler. Among the tools, TB-profiler, KvarQ and Mykrobe were those which identified the largest number of TB-MDR cases. Comparing the four most sensitive tools regarding resistance prediction, agreement was observed for 43 genomes. MAIN CONCLUSIONS Drug resistance profiling using next-generation sequencing offers rapid assessment of resistance-associated mutations, therefore facilitating rapid access to effective treatment.

Investigation of carbapenemases and aminoglycoside modifying enzymes of Acinetobacter baumannii isolates recovered from patients admitted to intensive care units in a tertiary-care hospital in Brazil

Abstract INTRODUCTION: Acinetobacter baumannii are opportunistic bacteria, highly capable of acquiring antimicrobial resistance through the production of carbapenemases and aminoglycoside modifying enzymes (AMEs). METHODS: Carbapenemase and AME genes were investigated in A. baumannii recovered from inpatients of a Brazilian hospital. RESULTS: The key genes found were bla OXA-51-like, the association ISAba1- bla OXA-23-like, and the AME genes aph(3´)-VI, aac(6´)-Ib, aac(3)-Ia, and aph(3´)-Ia. Different clusters spread through the institution wards. CONCLUSIONS: The dissemination of bla OXA-23-like and AME-carrying A. baumannii through the hospital highlights the need for improved preventive measures to reduce the spread of infection.

Pseudomonas aeruginosa in the ICU: prevalence, resistance profile, and antimicrobial consumption

Abstract INTRODUCTION: Pseudomonas aeruginosa is one of the main pathogens causing infection in intensive care units (ICUs) and usually presents antimicrobial resistance. METHODS: Data were obtained from ICUs between 2010 and 2013. RESULTS: P. aeruginosa had a prevalence of 14.5% of which 48.7% were multidrug resistant. We observed increasing resistance to carbapenems and polymyxin B and growing consumption of aminoglycosides, meropenem, ceftazidime, and polymyxin B. The regression impact between resistance and consumption was significant with respect to amikacin, imipenem, meropenem, and polymyxin B. CONCLUSIONS: Monitoring antimicrobial consumption and resistant microorganisms should be reinforced to combat antimicrobial- and multi-drug resistance.

Frequency of first and second-line drug resistance-associated mutations among resistant Mycobacterium tuberculosis clinical isolates from São Paulo, Brazil

BACKGROUND Tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium tuberculosis, and the number of new cases of multidrug resistant TB (MDR-TB), pre extensively drug-resistant TB (pre-XDR-TB) and extensively drug-resistant TB (XDR-TB) has increased considerably worldwide. OBJECTIVES Herein, using 156 M. tuberculosis isolates from 106 patients previously classified as MDR or pre-XDR or XDR isolates, we investigated the genetic mutation profiles associated with phenotypic resistances in patients with MDR-TB, pre-XDR-TB and XDR-TB, treatment outcomes and resistance evolution. METHODS Molecular analyses were performed by partial sequencing of the rpoB, katG, gyrA, gyrB, rrs genes and analysis of the fabG-inhA promoter region. Clinical, epidemiologic and demographic data were obtained from the TB Notification database system of São Paulo (TB-WEB) and the Information System for Special Tuberculosis Treatments (SITE-TB). FINDINGS Drug resistance was attributed to previously known mutations and a novel Asp449Val mutation in gyrB was observed in four isolates from the same patient. Ten patients had more than one isolate evaluated and eight of these patients displayed resistance progression. MAIN CONCLUSIONS The present study is the first to report the frequency of mutations related to second-line drug resistance in MDR-TB, pre-XDR-TB and XDR-TB isolates. The results could lead to the improvement of available technologies for the rapid detection of drug resistant TB.