Caracterización de ß-lactamasas de espectro extendido en aislamientos clínicos colombianos de Salmonella enterica no tifoidea de 1997 a 2022 / Characterization of extended spectrum ß-lactamases in Colombian clinical isolates of non-typhoidal Salmonella enterica between 1997 and 2022

Introducción. Salmonella spp. es un agente patógeno zoonótico transmitido al humano por el agua o los alimentos contaminados. La presencia de ß-lactamasas de espectro extendido es un creciente problema para la salud pública debido a que estas enzimas confieren resistencia contra las cefalosporinas de tercera y cuarta generación. Objetivo. Caracterizar las ß-lactamasas de espectro extendido en aislamientos de Salmonella spp. recibidos por el programa de vigilancia de enfermedad diarreica aguda o enfermedad transmitida por alimentos del Grupo de Microbiología del Instituto Nacional de Salud. Materiales y métodos. Entre enero de 1997 y junio de 2022, se recibieron 444 aislamientos de Salmonella spp. resistentes, por lo menos, a una de las cefalosporinas de tercera generación. El fenotipo de las ß-lactamasas de espectro extendido se identificó con la prueba de doble disco. El ADN se extrajo por ebullición y mediante PCR se amplificaron los genes bla CTX-M, bla SHVy : ' a ILM. Resultados. Todos los aislamientos fueron positivos para la prueba de ß-lactamasas de espectro extendido. Los resultados de la amplificación por PCR fueron: bla CTX-M + bla TLM (n=200), bla CTX-M (n=177), bla SHV(n=16), bla SHV + bla CTX-M (n=6), bla TLM (n=13) y bla SHV + bla CTX-M + bla TLM (n=3). Del total, 26 aislamientos fueron negativos para los genes evaluados. Los aislamientos positivos para ß-lactamasas de espectro extendido se identificaron en Bogotá y en 21 departamentos: Chocó, Magdalena, Meta, Bolívar, Casanare, Cesar, Córdoba, Quindío, Atlántico, Tolima, Cauca, Cundinamarca, Huila, Boyacá, Caldas, Norte de Santander, Risaralda, Antioquia, Nariño, Santander y Valle del Cauca. Conclusión. La resistencia a las cefalosporinas de tercera generación en aislamientos de Salmonella spp. fue generada principalmente por bla CTX-M. El 44 % (197/444) de los aislamientos presentó resistencia a ampicilina, tetraciclina, cloranfenicol y trimetoprim- sulfametoxazol Los serotipos portadores de ß-lactamasas de espectro extendido más frecuentes fueron S. Typhimurium y S. Infantis.

Introduction. Salmonella spp. is a zoonotic pathogen transmitted to humans through contaminated water or food. The presence of extended-spectrum ß-lactamases is a growing public health problem because these enzymes are resistant to third and fourth generation cephalosporins. Objective. To characterize extended-spectrum ß-lactamases in Salmonella spp. isolates received by the acute diarrheal disease/foodborne disease surveillance program of the Grupo de Microbiología of the Instituto Nacional de Salud. Materials and methods. A total of 444 Salmonella spp. isolates, resistant to at least one of the cephalosporins, were obtained between January 1997 and June 2022. The extended- spectrum ß-lactamases phenotype was identified by the double disk test. DNA extraction was carried out by the boiling method, and the bla CTX-M, bla SHV, and bla TLM genes were amplified by PCR. Results. All the isolates were positive for the extended-spectrum ß-lactamases test. The genes identified were: bla CTX-M + ba TLM (n=200), bla CTX-M (n=177), bla SHV(n=16), bla SHV + bla CTX-M (n=6), bla TLM (n=13) and bla SHV + bla CTX-M + bla TLM (n=3). Twenty-six isolates were negative for the evaluated genes. Positive extended-spectrum ß-lactamases isolates were identified in Bogotá and 21 departments: Chocó, Magdalena, Meta, Bolívar, Casanare, Cesar, Córdoba, Quindío, Atlántico, Tolima, Cauca, Cundinamarca, Huila, Boyacá, Caldas, Norte de Santander, Risaralda, Antioquia, Nariño, Santander y Valle del Cauca. Conclusion. Resistance to third generation cephalosporins in Salmonella spp. isolates was mainly caused by bla CTX-M. Isolates were resistant to ampicillin, tetracycline, chloramphenicol, and trimethoprim-sulfamethoxazole (44 %; 197/444). The most frequent extended-spectrum ß-lactamases-expressing serotypes were Salmonella Typhimurium and Salmonella Infantis.

Otitis externa maligna con diseminación hematógena de Pseudomonas aeruginosa resistente a carbapenémicos

Pseudomonas aeruginosa en una bacteria Gram negativa no fermentadora que produce diversos tipos de infecciones severas en inmunocompetentes e inmunodeprimidos. Una de estas infecciones es la otitis externa maligna, la cual se presenta principalmente en personas con diabetes mellitus y puede tener una evolución tórpida cursando con osteomielitis de base de cráneo y parálisis de nervios craneales. El tratamiento es individualizado y principalmente conservador con antibioticoterapia guiada por cultivo. La bacteria aislada en la mayoría de los casos reportados es sensible a los antibióticos anti-pseudomónicos. Reportamos un caso de presentación inusual de otitis externa maligna por Pseudomonas aeruginosa resistente a carbapenémicos con evidencia sugerente de compromiso bilateral y en el cual se aisló al mismo germen en urocultivo y hemocultivos, lo que indicaría una diseminación hematógena del microorganismo.

Pseudomonas aeruginosa is a non-fermenting Gram-negative bacterium that produces several types of severe infections in immunocompetent and immunosuppressed patients. One of these infections is malignant otitis externa, which occurs mainly in people with diabetes mellitus and can have a torpid evolution coursing with osteomyelitis of skull base and cranial nerve palsies. Treatment is individualized and mainly conservative with culture-guided antibiotic therapy, with isolated pseudomonas being sensitive to anti-pseudomonal antibiotics in the majority of reported cases. We report a case of unusual presentation of malignant otitis externa caused by Pseudomonas aeruginosa resistant to carbapenems with suggestive evidence of bilateral involvement and in which the same germ was isolated in urine and blood cultures, which would indicate hematogenous dissemination of the microorganism.

Resistencia antimicrobiana, una pandemia silenciosa / Antimicrobial resistance, a silent pandemic / Resistência antimicrobiana, uma pandemia silenciosa

Introducción: la resistencia a los antimicrobianos ha sido una problemática creciente a nivel global, la problemática afecta no solo la salud de personas, animales y el ambiente en general, sino que ha generado impactos de índole productivo y comercial. Una de las estrategias para abordar esta problemática es el enfoque de una salud. Este enfoque destaca la participación multidisciplinaria para combatir la resistencia antimicrobiana; y es así que cada profesión o actividad laboral genera unas responsabilidades innatas para la profesión veterinaria. Los veterinarios tienen un rol fundamental para este propósito, ya que son ellos quienes integran la aplicabilidad de estrategias de promoción y prevención a nivel agropecuario, y de consolidación e interlocución entre los diferentes componentes del enfoque (animal, humano, ambiente) desde el ámbito de la salud pública veterinaria. Materiales y Método: se realizó una búsqueda de la literatura en diferentes bases de datos, con el objetivo de realizar una revisión actualizada sobre la resistencia antimicrobiana. Resultados: dentro de las principales estrategias se debería fomentar un uso adecuado y bajo prescripción de antimicrobianos en la producción animal. Promover buenas prácticas de higiene, bioseguridad y vacunación, facilitando un correcto diagnóstico de enfermedades infecciosas en animales. Discusión: la adopción de normas internacionales para el uso responsable de los antibióticos y las directrices establecidas por la Organización Mundial de la Salud y Organización de las Naciones Unidas para la Alimentación y la Agricultura, a través del Codex Alimentarius y la Organización Mundial de Sanidad Animal, son fundamentales para hacer frente al desafío que representa el problema de la resistencia a los antimicrobianos.

Introduction: Antimicrobial resistance has been a growing problem at a global level, affecting not only the health of people, animals and the environment in general, but it has also generated impacts of a productive and commercial nature. One of the strategies to address this problem is the one-health approach. This approach emphasizes multidisciplinary participation to combat antimicrobial resistance; and thus, each profession or work activity generates innate responsibilities for the veterinary profession. Veterinarians have a fundamental role for this purpose, since they are the ones who integrate the applicability of promotion and prevention strategies at the agricultural level, and of consolidation and interlocution between the different components of the approach (animal, human, environment) from the field of veterinary public health. Materials and Method: a literature search was carried out in different databases, with the aim of carrying out an updated review on antimicrobial resistance. Results: one of the main strategies should be to promote an adequate use and under prescription of antimicrobials in animal production. Promote good hygiene, biosecurity and vaccination practices, facilitating a correct diagnosis of infectious diseases in animals. Discussion: the adoption of international standards for the responsible use of antibiotics and the guidelines established by the World Health Organization and the Food and Agriculture Organization of the United Nations, through Codex Alimentarius and the World Organization for Animal Health, are fundamental to face the challenge posed by the problem of antimicrobial resistance.

Introdução: A resistência antimicrobiana tem sido um problema crescente em todo o mundo, afetando não apenas a saúde dos seres humanos, dos animais e do meio ambiente em geral, mas também causando impactos na produção e no comércio. Uma das estratégias para lidar com esse problema é a abordagem One Health. Essa abordagem enfatiza o envolvimento multidisciplinar no combate à resistência antimicrobiana, com cada profissão ou atividade de trabalho gerando responsabilidades inatas à profissão veterinária. Os veterinários têm um papel fundamental nesse sentido, pois são eles que integram a aplicabilidade das estratégias de promoção e prevenção em nível agropecuário e de consolidação e interlocução entre os diferentes componentes da abordagem (animal, humano, ambiental) do campo da saúde pública veterinária. Materiais e Métodos: foi realizada uma pesquisa bibliográfica em diferentes bases de dados, com o objetivo de realizar uma revisão atualizada sobre a resistência antimicrobiana. Resultados: uma das principais estratégias deve ser a promoção do uso adequado e com baixa prescrição de antimicrobianos na produção animal. Promover boas práticas de higiene, biossegurança e vacinação, facilitando o diagnóstico correto de doenças infecciosas em animais. Discussão: A adoção de padrões internacionais para o uso responsável de antibióticos e as diretrizes estabelecidas pela Organização Mundial da Saúde e pela Organização das Nações Unidas para Agricultura e Alimentação, por meio do Codex Alimentarius e da Organização Mundial de Saúde Animal, são essenciais para enfrentar o desafio representado pelo problema da resistência antimicrobiana.

Challenges of Multidrug-resistant New Delhi Metallo-beta-Lactamase (NDM-1)-producing Enterobacteriaceae in Kidney Transplant Patients / Desafios da Enterobacteriaceae produtora de New Delhi Metalo-beta-Lactamase (NDM-1) multirresistente em pacientes com transplante renal

Abstract Background: The emergence of multidrug-resistant NDM-1-producing enterobacteriaceae strains has become a threat to inpatients, especially to immunosuppressed ones, such as kidney transplant recipients. NDM-1 is a carbapenemase that makes gram-negative bacteria resistant to many types of antibiotics. The incidence of carbapenemase-producing enterobacteria infection in solid organ transplant recipients is around 3 to 10%, with a mortality rate of up to 30%. Methods: We present a case series of 4 patients with NDM-1-producing enterobacteria isolated in urine cultures or rectal swabs. We also conducted a cross-sectional study 30 days after patient identification, collecting surveillance cultures (rectal swab) from all inpatients to assess the extent of spread of this resistance mechanism; a total of 101 patients were included. Results: Two patients were adequately treated with negative control cultures. The other two patients were not treated because they were asymptomatic and had subsequent negative urine cultures. No new colonization was identified in the cross-sectional screening, and no new cases of urinary NDM-1 infection were recorded after a 4-year follow-up. Conclusion: Surveillance for infections caused by multidrug-resistant strains in hospitals treating immunosuppressed patients should be continued and prompt action should be taken in cases of outbreaks of multidrug-resistant infections.

Resumo Histórico: O surgimento de cepas multirresistentes de enterobacteriaceae produtoras de NDM-1 tornou-se uma ameaça para pacientes hospitalizados, especialmente para os imunossuprimidos, como os receptores de transplante renal. NDM-1 é uma carbapenemase que torna as bactérias gram-negativas resistentes a muitos tipos de antibióticos. A incidência de infecção por enterobactérias produtoras de carbapenemas em receptores de transplante de órgãos sólidos é de cerca de 3 a 10%, com uma taxa de mortalidade de até 30%. Métodos: Apresentamos uma série de casos de 4 pacientes com enterobactérias produtoras de NDM-1 isoladas em culturas de urina ou esfregaços retais. Também realizamos um estudo transversal 30 dias após a identificação do paciente, coletando culturas de vigilância (esfregaço retal) de todos os pacientes internados para avaliar a extensão de disseminação deste mecanismo de resistência; foram incluídos um total de 101 pacientes. Resultados: Dois pacientes foram tratados adequadamente com culturas de controle negativo. Os outros dois pacientes não foram tratados porque eram assintomáticos e tiveram culturas de urina negativas subsequentes. Não foi identificada nenhuma nova colonização na triagem transversal, e não foram registrados novos casos de infecção urinária por NDM-1 após um acompanhamento de 4 anos. Conclusão: A vigilância de infecções causadas por cepas multirresistentes em hospitais que tratam pacientes imunossuprimidos deve ser continuada e devem ser tomadas medidas imediatas em casos de surtos desses tipos de infecções.

Cálculo de los Días de Terapia Antimicrobiana (DOT) en Cuidados Intensivos Pediátricos: una propuesta de metodología basada en el sistema informático de dispensación de medicamentos

Introducción: El método recomendado para la medición de consumo de antimicrobianos (AMB) en pediatría es el cálculo del indicador Días de Terapia estandarizado por ocupación (DOT-std). Sin embargo, en hospitales que no cuentan con fichas electrónicas, obtener el numerador de los días de terapia (DOT) requiere revisión directa de las indicaciones del paciente, dificultando su aplicabilidad. Objetivos: Validar el sistema de registros electrónicos de dispensación de medicamentos desde farmacia como fuente para el cálculo de DOT y DOT-std en la Unidad de Cuidados Intensivos Pediátrica (UCIP). Materiales y Métodos: Se revisaron las prescripciones de AMB desde la ficha clínica (método manual) y se compararon con los registros de dispensación de AMB a la UCIP (método informático) obtenidos del sistema de medicamentos de farmacia. Se evaluó la concordancia entre los DOT obtenidos mediante el Coeficiente de Correlación Intraclase. Resultados: Los AMB más utilizados fueron vancomicina, meropenem y piperacilina/tazobactam. En 9 de 12 AMB se encontró concordancia significativa entre ambos métodos. Conclusiones: Tras un proceso de validación local, los registros del sistema informático de dispensación de medicamentos desde farmacia podrían utilizarse para el cálculo de DOT en pediatría en hospitales que no cuenten con una ficha electrónica que permita su cálculo directo.

Background: The recommended indicator for measuring antimicrobial (AMB) consumption in pediatric patients is the Days of Therapy indicator (DOT), which is then standardized by hospital occupancy rates (DOT-std). However, in hospitals that do not have electronic health records, obtaining the DOT requires a direct review of each pharmacological indication, which is not feasible in the long term. Aims: To validate electronic records from the pharmacy dispensation system as a source for calculating DOT and estimating DOT-std in a Pediatric Intensive Care Unit (PICU). Methods: AMB prescriptions at the PICU of a university hospital were directly reviewed (manual method) and compared with AMB dispensation records (computer method) obtained from the hospital pharmacy system. The Intraclass Correlation Coefficient was used to evaluate the agreement between the DOT obtained by both methods. Results: The most used AMB were vancomycin, meropenem, and piperacillin/tazobactam. A significant agreement between the DOT obtained by using manual and computer methods was found in 9 of 12 evaluated AMB. Conclusions: After a local validation process, the electronic records of the pharmacy drug dispensation system could be considered a valid source for calculating DOT in PICUs in hospitals where electronic health records with prescription data are not yet available.

Resistência bacteriana consecutiva do uso indiscriminado de antibióticos: revisão integrativa / Consecutive bacterial resistance from the indiscriminate use of antibiotic: integrative review / Resistencia bacteriana consecutiva al uso indiscriminado de antibióticos: revisión integrativa

O abandono do tratamento de tuberculose é uma questão relevante e preocu- pante na saúde pública mundial. Mediante uma revisão integrativa, esse estudo busca identificar os possíveis fatores que levam ao abandono do tratamento. Foi realizada pes- quisa em estudos indexados nas bases de dados: Biblioteca Virtual em Saúde (BVS) e Scientific Eletronic Library Online (SciELO), no período de 2017 a 2021, utilizando-se os seguintes descritores (DeCS): tuberculose, agente antituberculose e tuberculose pul- monar. Ao fim, foram selecionados onze estudos, publicados nos idiomas português, es- panhol e inglês. Os resultados mostraram que o abandono está relacionado a fatores de diversas esferas, com destaque para as esferas social, da saúde e a do próprio tratamento. Como perfil das pessoas dos casos de abandono, em geral, observou-se que elas são eco- nomicamente ativas, com faixa etária entre 15 e 49 anos, possuem baixa escolaridade, baixa renda e é comum que os usos abusivos de álcool e drogas sejam apresentados como comorbidades relevantes. Portanto, o trabalho evidenciou os principais fatores associados ao abandono do tratamento de tuberculose e a importância da participação de diferentes atores como forças que somarão para diminuir a ocorrência do problema em questão.

Introduction: Currently, it is understood that bacterial resistance is an ecological event arising from mutations, or selection, occurring as a response to the use of antibiotics and their presence in the environment, causing the change of genes. Objective: To evaluate how the indiscriminate use of antibiotics affects bacterial resistance. Materials and Methods: This is a bibliographical research of the integrative literature review type. Results: The practice and indiscriminate use of medication result from sociocultural factors, economic conditions, access to health services, malpractice in medication prescription and lack of surveillance when purchasing medication. The presence of "home pharmacies" in the study was considered alarming, being a risk factor for the self-medication of antibiotics, such stored drugs show a possible non-completion of a treatment in an adequate period, justified by the absence of pain symptoms, or by individuals who did not consider the drug to be effective. Conclusion: It is necessary to comply with existing legislation in order to regulate the sale of antibiotics and prevent the irrational use of drugs.

Introducción: Actualmente, se entiende que la resistencia bacteriana es un evento ecológico derivado de mutaciones, o selección, que ocurre como respuesta al uso de antibióticos y su presencia en el ambiente, provocando el cambio de genes. Objetivo: Evaluar cómo el uso indiscriminado de antibióticos afecta la resistencia bacteriana. Materiales y Métodos: Se trata de una investigación bibliográfica del tipo revisión integradora de literatura. Resultados: La práctica y uso indiscriminado de medicamentos resultan de factores socioculturales, condiciones económicas, acceso a los servicios de salud, mala práctica en la prescripción de medicamentos y falta de vigilancia en la compra de medicamentos. Se consideró alarmante la presencia de "farmacias domiciliarias" en el estudio, siendo un factor de riesgo para la automedicación de antibióticos, tales medicamentos almacenados evidencian una posible no finalización de un tratamiento en un período adecuado, justificado por la ausencia de síntomas de dolor , o por personas que no consideraron que el fármaco fuera eficaz. Conclusión: Es necesario cumplir con la legislación vigente para regular la venta de antibióticos y prevenir el uso irracional de medicamentos.

Epidemiology of antimicrobial resistance in bacteria isolated from inpatient and outpatient samples, Ecuador, 2018 / Características epidemiológicas de la resistencia antimicrobiana en cepas bacterianas aisladas en pacientes de servicios hospitalarios y ambulatorios de Ecuador, 2018 / Epidemiologia da resistência aos antimicrobianos em bactérias isoladas de amostras hospitalares e ambulatoriais no Equador, 2018

ABSTRACT Objective. To compare the epidemiology of antimicrobial resistance in bacteria isolated from inpatient and outpatient samples in Ecuador. Methods. A secondary analysis was done of data on bacteria isolated from inpatient and outpatient samples. Data were taken from the 2018 national antimicrobial resistance surveillance database of the National Reference Center for Antimicrobial Resistance. The variables included were: age, sex, inpatient versus outpatient setting, type of specimen, bacterial species identified, pattern of resistance to antibiotics, and geographic area. Results. Data from 57 305 bacterial isolates were included in the study: 48.8% were from hospitalized patients, 55.7% were from women, and 60.1% were from patients older than 45 years. Urine (42.9%) and blood (12.4%) were the most common clinical samples. Overall, 77.1% of bacterial isolates were gram-negative (83% and 71% in outpatients and inpatients, respectively). The most common gram-positive and gram-negative species were Staphylococcus aureus and Escherichia coli, respectively. Antimicrobial resistance levels were high (up to 80% for some antimicrobial drugs), and were higher in hospitalized patients compared with outpatients. A variety of carbapenemases were found to confer resistance to carbapenems (antibiotics of last resort) in gram-negative bacteria. Conclusions. The study findings provide an important baseline on antimicrobial resistance in Ecuador. This will allow the strengthening of guidelines of the surveillance system, the creation of public policies for standardization of laboratory methodologies, the proper handling of information, and the development of empirical therapy guidelines based on local epidemiology.

RESUMEN Objetivo. Comparar las características epidemiológicas de la resistencia a los antimicrobianos en cepas bacterianas aisladas de muestras de pacientes de servicios hospitalarios y ambulatorios en Ecuador. Métodos. Se realizó un análisis secundario de los datos sobre cepas bacterianas aisladas en muestras de pacientes de servicios hospitalarios y ambulatorios. Se recogieron los datos de la base de datos nacional del 2018 para la vigilancia de la resistencia a los antimicrobianos del Centro de Referencia Nacional para la Resistencia a los Antimicrobianos. Las variables incluidas fueron: edad, sexo, entorno hospitalario frente a entorno ambulatorio, tipo de muestra, especies bacterianas detectadas, patrón de resistencia a los antibióticos y zona geográfica. Resultados. En el estudio se incluyeron datos de 57 305 cepas aislamientos bacterianos: 48,8% fueron de pacientes hospitalizados, 55,7% fueron de mujeres y 60,1% fueron de pacientes mayores de 45 años. La orina (42,9%) y la sangre (12,4%) fueron las muestras clínicas más comunes. En general, 77,1% de las cepas bacterianas aisladas fueron gramnegativas (83% y 71% en pacientes de servicios ambulatorios y hospitalarios, respectivamente). Las especies grampositivas y gramnegativas más comunes fueron Staphylococcus aureus y Escherichia coli, respectivamente. Los niveles de resistencia a los antimicrobianos fueron elevados (hasta 80% en el caso de algunos fármacos antimicrobianos) y fueron más elevados en los pacientes de servicios hospitalarios en comparación con los pacientes de servicios ambulatorios. Se encontró que una variedad de carbapenemasas confiere resistencia a los carbapenémicos (antibióticos de último recurso) en bacterias gramnegativas. Conclusiones. Los resultados del estudio proporcionan una línea de base importante sobre la resistencia a los antimicrobianos en Ecuador, que permitirá el fortalecimiento de las directrices del sistema de vigilancia, la creación de políticas públicas para la estandarización de los métodos de laboratorio, una adecuada gestión de la información y la elaboración de orientaciones de tratamiento empírico basadas en las características epidemiológicas locales.

RESUMO Objetivo. Comparar a epidemiologia da resistência aos antimicrobianos em bactérias isoladas de amostras hospitalares e ambulatoriais no Equador. Métodos. Foi feita uma análise secundária de dados sobre bactérias isoladas de amostras hospitalares e ambulatoriais. Os dados foram obtidos do banco de dados nacional de vigilância da resistência aos antimicrobianos de 2018 do Centro Nacional de Referência para a Resistência aos Antimicrobianos. As variáveis incluídas foram: idade, sexo, ambiente hospitalar versus ambiente ambulatorial, tipo de espécime, espécies bacterianas identificadas, padrão de resistência a antibióticos e área geográfica. Resultados. Foram incluídos no estudo os dados de 57 305 isolados bacterianos: 48,8% eram de pacientes hospitalizados, 55,7% eram de mulheres e 60,1% eram de pacientes com mais de 45 anos. As amostras clínicas mais comuns foram urina (42,9%) e sangue (12,4%). No total, 77,1% dos isolados bacterianos eram gram-negativos (83% e 71% em pacientes ambulatoriais e pacientes internados, respectivamente). As espécies gram-positivas e gram-negativas mais comuns foram Staphylococcus aureus e Escherichia coli, respectivamente. Os níveis de resistência aos antimicrobianos foram elevados (até 80% para alguns antimicrobianos) e foram mais elevados em pacientes hospitalizados em comparação com pacientes ambulatoriais. Foram encontradas várias carbapenemases que conferem resistência aos carbapenêmicos (antibióticos de último recurso) em bactérias gram-negativas. Conclusões. Os resultados do estudo fornecem uma importante linha de base sobre a resistência aos antimicrobianos no Equador. Isto permitirá o fortalecimento das diretrizes do sistema de vigilância, a criação de políticas públicas para padronização de metodologias laboratoriais, o manejo adequado de informações e o desenvolvimento de diretrizes para a antibioticoterapia empírica com base na epidemiologia local.

Distribution and drug resistance of pathogenic bacteria for infection after liver transplantation / 临床肝胆病杂志

Objective To investigate the distribution and drug resistance of pathogenic bacteria for infection after liver transplantation, and to provide a scientific basis for the rational clinical application of antibiotics. Methods The pathogenic bacteria isolated from the specimens of 904 patients with infection after liver transplantation in The Affiliated Hospital of Qingdao University from March 2014 to December 2021 were analyzed in terms of distribution and drug resistance. WHONET 5.6 software was used to perform a statistical analysis of strains and bacterial resistance rate, and Excel was used to analyze the sources of specimens, composition ratios, and distribution of pathogenic bacteria. Results A total of 2 208 non-repetitive pathogenic bacteria were isolated, mainly from the specimens of respiratory tract (31.25%), bile (22.28%), ascites (13.18%), blood (8.38%), and drainage fluid (4.62%). The top 10 pathogenic bacteria were Klebsiella pneumoniae subspecies (10.69%), Enterococcus faecium (10.42%), Escherichia coli (8.24%), Pseudomonas aeruginosa (8.24%), Staphylococcus epidermidis (8.06%), Acinetobacter baumannii (7.93%), Stenotrophomonas maltophilia (6.61%), Enterobacter cloacae (3.22%), Staphylococcus haemolyticus (3.08%), and Staphylococcus aureus (2.94%), accounting for 69.43% of the total pathogenic bacteria. Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Klebsiella pneumoniae subspecies, and Acinetobacter baumannii were the main pathogenic bacteria isolated from respiratory tract specimens; Enterococcus faecium was the main pathogenic bacterium isolated from bile, ascites, and drainage fluid specimens; Escherichia coli , Staphylococcus epidermidis , and Klebsiella pneumoniae subspecies were the main pathogenic bacteria isolated from blood specimens. Drug sensitivity data showed that Enterobacterales bacteria had a relatively high resistance rate to cephalosporins and fluoroquinolones and a resistance rate of 50% to macrolides, fluoroquinolones, sulfonamides, and lincomycin, and a small part of these strains were resistant to linezolid and quinupristin/dalfopristin (< 3%), with no Staphylococcus epidermidis strains resistant to tigecycline and vancomycin. A total of 287 drug-resistant strains were monitored, accounting for 13%, among which there were 128 carbapenem-resistant Acinetobacter baumannii strains, 88 carbapenem-resistant Pseudomonas aeruginosa strains, 26 carbapenem-resistant Klebsiella pneumoniae subspecies strains, 11 carbapenem-resistant Escherichia coli strains, 23 methicillin-resistant Staphylococcus aureus strains, and 11 vancomycin-resistant Enterococcus strains. The carbapenem-resistant Klebsiella pneumoniae subspecies strains mainly produced serine carbapenemase, and the carbapenem-resistant Escherichia coli strains mainly produced metal β-lactamase. Conclusion Gram-negative bacteria are the main pathogenic bacteria for infection after liver transplantation, and there are differences in the distribution of pathogenic bacteria between different types of specimens. The resistance rate of some strains tend to increase, and therefore, it is necessary to strengthen the management of nosocomial infection and antibiotics.

Advances in researches of polymyxin resistance mechanism in Klebsiella pneumoniae / 中华检验医学杂志

In recent years, the carbapenem-resistant Klebsiella pneumoniae (CRKP) continues to significantly threaten public health. The limited therapeutic options are increasingly challenging for clinicians to reintroduce the polymyxin as last-resort drug, with the results that polymyxin resistance is not scarce in settings. The polymyxin resistance mechanism is diversified, mainly the modification of the lipopolysaccharide (LPS). In addition to phoPQ, pmrAB, crrAB and mgrB on chromosome, plasmid-carried mcr gene have been found to mediate the LPS modification. The mgrB gene variation plays an important role in polymyxin resistance. Above all, the aim of the current review is to discuss the mechanism of polymyxin resistance mechanism in Klebsiella pneumoniae provide insights for preventing this phenomenon.

Evaluation of NG-Test Carba5 for rapid detection of carbapenemases / 中华检验医学杂志

Objective:To evaluate the clinical value of NG-Test Carba5 for rapid detection of carbapenemases produced by carbapenem-resistant Enterobacteriaceae (CRE) strains. Methods:A total of 1 210 CRE strains were collected during 2018-2022 from 77 hospitals in 21 provinces of China and were subjected to NG-Test Carba5 for rapid detection of carbapenemase. The whole genome sequencing (WGS) analysis was referenced as the gold standard method.Results:Overall, the NG-Test Carba5 demonstrated excellent performance in detection of five kinds of carbapenemases [Klebsiella pneumoniae carbapenemase (KPC), New Delhi metallo-β-lactamase (NDM), imipenemase metallo-β-lactamase (IMP), Verona integron-encoded metallo-beta-lactamase (VIM) and oxacillinase-48-type carbapenemases(OXA-48)] from CRE strains, with a sensitivity of 98.47% (1 161/1 179), specificity of 100% (31/31), and positive predictive value of 100% (1 161/1 161). The sensitivity for detection of NDM, IMP, OXA and VIM reached 100% (307/307), and 97.70% (763/781) for KPC. For 11 strains carrying blaKPC-25, blaKPC-78, or blaKPC-93, NG-Test Carba5 reported positive KPC detection (11/11). For strains carrying blaKPC-33 and blaKPC-77, however, NG-Test Carba5 delivered negative results. Additionally, for those strains co-producing two or three kinds of carbapenemases, NG-Test Carba5 was able to report all of the targets with a sensitivity of 100% (91/91). Conclusions:NG-Test Carba5 showed excellent performance in rapid and accurate detection of carbapenemases from CRE strains. Nonetheless, for those strains with negative results, some other phenotypic and genotypic methods should be implemented alongside to avoid missing targets.

Visualization analysis of helicobacter pylori drug resistance research at home and abroad based on Citespace / 中国医师杂志

Objective:To analyze the research progress and hotspots on drug resistance of helicobacter pylori in China and abroad since 2000, in order to provide theoretical reference and basis for the study of digestive system diseases.Methods:The Chinese and English literature related to helicobacter pylori resistance, which were included in the Chinese National Knowledge Infrastructure (CNKI) database and the Web of Science database, were searched from 2000 to 2021. We imported the retrieved literature into Citespace6.1.R2 software, performed visual analysis on authors, countries and institutions, keywords, cited literature, and drew visual graphs.Results:A total of 2 824 Chinese literature and 1 885 English literature were included. The authors with the highest volume of publications in Chinese and English literature are Hu Fulian and Gisbert JP, respectively. The institutions with the highest volume of publications are the First School of Medicine, Beijing University and the Baylor School of Medicine in the United States. The keywords with high centrality in Chinese literature include clarithromycin, eradication rate, drug resistance, amoxicillin, metronidazole, etc. In the analysis of cited literature, it was observed that the Maastricht Consensus report holds an important position in this field.Conclusions:The use of Citespace visualization analysis has intuitively elucidated the research hotspots on the drug resistance of Helicobacter pylori.

Actividad antibacteriana de actinomicetos frente a Escherichia coli y Staphylococcus aureus multirresistentes de origen hospitalario / Antibacterial activity of actimycetes against multiresistant Escherichia coli and Staphylococcus aureus isolated from a hospital

Introducción: La resistencia a los antimicrobianos (RAM) es un problema de salud pública que manifiesta la disminuida eficacia de estos agentes en la prevención y tratamiento de una proporción cada vez más amplia de patologías. Los actinomicetos son un grupo bacteriano importante de productores de metabolitos activos contra patógenos. Objetivo: Aislar actinomicetos del bosque tropical de Nariño, con potencial producción de metabolitos inhibitorios contra bacterias multidrogo-resistentes. Materiales y métodos: Se tomaron muestras de suelo de Bosque Tropical Húmedo de la Reserva Natural del Río Ñambí, se analizaron microbiológica y molecularmente. Se estimuló la producción in vitro de metabolitos secundarios y evaluó el efecto inhibitorio de estos extractos contra las bacterias multidrogo-resistentes Escherichia coli y Staphylococcus aureus. Resultados: Se obtuvieron 11 aislados presuntivos, se confirmó que cuatro de ellos correspondieron al género Streptomyces sp. Las pruebas de inhibición contra bacterias multidrogo-resistentes E. coli y S. aureus, permitieron verificar que el aislado P3772 fue el más eficiente en la inhibición de los patógenos. Conclusiones: Todos los actinomicetos evaluados presentan actividad antibacteriana contra al menos una de las bacterias patógenas estudiadas; destacando el aislado P3772, que inhibe a E. coli y S. aureus. Se espera caracterizar los compuestos vinculados a la actividad antibacteriana.

Introduction: Antimicrobial resistance (AR) is a public health problem that reveals the diminished efficacy of these agents in the prevention and treatment of an increasingly larger number of pathologies. Actinomycetes are an important bacterial producer group of metabolites that are active against pathogens. Objective: To isolate actinomycetes from the tropical forest of Nariño (Colombia), which have the potential to produce inhibitory metabolites against multi-drug resistant bacteria. Materials and methods: Soil samples were taken from the Humid Tropical Forest of the Río Ńambí Natural Reserve and analyzed through microbiological and molecular assays. In vitro production of secondary metabolites was first stimulated, followed by the assessment of the inhibitory effect of these extracts against multi-drug resistant Escherichia coli and Staphylococcus aureus. Results: 11 presumptive isolates were obtained, confirming that four of them corresponded to the Streptomyces sp. genus. The bacterial isolate P3772 was identified as the one with the highest inhibitory effect against multi-drug resistant E. coli and S. aureus. Conclusions: All the actinomycetes evaluated presented antibacterial activity. The isolate P3772 stands out, which inhibited both E. coli and S. aureus. The compounds associated with this antibacterial activity will be characterized in future studies.

Resistência antimicrobiana em uroculturas de moradores das Zonas Norte e Nordeste de Porto Alegre / Antimicrobial resistance in urine cultures of residents of North and Northeast Porto Alegre / Resistencia a los antimicrobianos en urocultivos de residentes de las Zonas Norte y Noreste de Porto Alegre

Introdução: Infecção urinária é motivo comum de consulta na Atenção Primária, requerendo tratamento empírico. Para a seleção do antimicrobiano, é necessário conhecer o perfil de resistência dos uropatógenos na comunidade. Objetivo: Analisar o perfil de resistência antimicrobiana em uroculturas realizadas em pacientes da Atenção Primária à Saúde do Serviço de Saúde Comunitária do Grupo Hospitalar Conceição, de julho de 2017 a junho de 2019. Métodos: Estudo transversal, observacional e descritivo com uroculturas de pacientes ambulatoriais das Unidades de Saúde do Serviço de Saúde Comunitária do Grupo Hospitalar Conceição, nas Zonas Norte e Nordeste de Porto Alegre, de julho de 2017 a junho de 2019. Os dados das uroculturas foram fornecidos pelo laboratório do Grupo Hospitalar e analisados por meio das proporções, por sexo, micro-organismo e resistência antimicrobiana. Resultados: Encontraram-se 2.000 uroculturas positivas no período, principalmente por Escherichia coli (75,50%), Klebsiella pneumoniae (7,80%), Staphylococcus saprophyticus (4,95%), Enterococcus specie (3,35%) e Proteus mirabilis (2,85%). Entre os antibióticos orais testados, a maior resistência foi para ampicilina (48,95%), seguida por sulfametoxazol+trimetoprima (25,85%), norfloxacino (18,05%), ciprofloxacino (18,00%), amoxicilina+clavulanato (11,05%) e nitrofurantoína (8,60%). Considerando-se apenas E. coli, as resistências foram 47,75% para ampicilina, 29,74% para sulfametoxazol+trimetoprima, 19,74% para norfloxacino e ciprofloxacino, 8,08% para amoxicilina+clavulanato e 1,99% para nitrofurantoína. Conclusões: O perfil de resistência antimicrobiana nas Zonas Norte e Nordeste de Porto Alegre sugere que sejam utilizados para tratamento empírico de infecção do trato urinário nessa localidade nitrofurantoína ou amoxicilina+clavulanato.

Introduction: Urinary tract infection is a common reason for consultation in primary care, requiring empirical treatment. For the selection of the antimicrobial, it is necessary to know the resistance profile of uropathogens in the community. Objective: To analyze the profile of antimicrobial resistance in urine cultures performed on primary health care patients from the Community Health Service of Grupo Hospitalar Conceição from July 2017 to June 2019. Methods: Cross-sectional, observational and descriptive study with urine cultures of outpatients from the Health Units from the Community Health Service of Grupo Hospitalar Conceição, in North and Northeast Porto Alegre, Brazil, from July 2017 to June 2019. The data on urine cultures were provided by the Grupo Hospitalar laboratory and analyzed through proportions, by sex, microorganism, and antimicrobial resistance. Results: Two thousand positive urine cultures were found in the period, mainly for Escherichia coli (75.50%), Klebsiella pneumoniae (7.80%), Staphylococcus saprophyticus (4.95%), Enterococcus specie (3.35%) and Proteus mirabilis (2.85%). Among the oral antibiotics tested, the most frequent resistance was to ampicillin (48.95%), followed by trimethoprim+sulfamethoxazole (25.85%), norfloxacin (18.05%), ciprofloxacin (18.00%), amoxicillin-clavulanate (11.05%) and nitrofurantoin (8.60%). Considering only E. coli, resistance was 47.75% to ampicillin, 29.74% to trimethoprim+sulfamethoxazole, 19.74% to norfloxacin and ciprofloxacin, 8.08% to amoxicillin-clavulanate and 1.99% to nitrofurantoin. Conclusions: The profile of antimicrobial resistance in the North and Northeast Zones of Porto Alegre suggests that nitrofurantoin or amoxicillin-clavulanate should be used for empirical treatment of urinary tract infection in this locality.

Introducción: La infección del tracto urinario es un motivo frecuente de consulta en atención primaria, requiriendo tratamiento empírico. Para la selección del antimicrobiano, es necesario conocer el perfil de resistencia de los uropatógenos en la comunidad. Objetivo: Analizar el perfil de resistencia antimicrobiana en urocultivos realizados en pacientes de atención primaria de salud de Serviço de Saúde Comunitária de Grupo Hospitalar Conceição de julio de 2017 a junio de 2019. Métodos: Estudio transversal, observacional y descriptivo con urocultivos de pacientes ambulatorios de las Unidades de Salud de Serviço de Saúde Comunitária de Grupo Hospitalar Conceição, en las Zonas Norte y Nordeste de Porto Alegre, de julio de 2017 a junio de 2019. Los datos de urocultivos fueron proporcionados por el laboratorio de Grupo Hospitalar y analizados a través de proporciones, por sexo, microorganismos y resistencia a los antimicrobianos. Resultados: En el período se encontraron 2.000 urocultivos positivos, principalmente por Escherichia coli (75,50%), Klebsiella pneumoniae (7,80%), Staphylococcus saprophyticus (4,95%), Enterococcus especie (3,35%) y Proteus mirabilis (2,85%). Entre los antibióticos orales probados, la mayor resistencia fue para la ampicilina (48,95%), seguida de sulfametoxazol+trimetoprima (25,85%), norfloxacina (18,05%), ciprofloxacina (18,00%), amoxicilina+clavulanato (11,05%) y nitrofurantoína (8,60%). %). Considerando solo a E. coli, la resistencia fue del 47,75% para ampicilina, 29,74% para sulfametoxazol + trimetoprima, 19,74% para norfloxacina y ciprofloxacina, 8,08% para amoxicilina + clavulanato y 1,99% para nitrofurantoína. Conclusiones: El perfil de resistencia a los antimicrobianos en las regiones Norte y Nordeste de Porto Alegre sugiere que se utilizan para el tratamiento empírico de la infección del tracto urinario en esta localidad nitrofurantoína o amoxicilina+clavulanato.

Etiological characteristics of infection after percutaneous biliary drainage or stent implantation for malignant biliary obstruction / 临床肝胆病杂志

Objective To investigate the etiological characteristics of infection after percutaneous biliary drainage or stent implantation in patients with malignant biliary obstruction (MBO). Methods Clinical data were collected from MBO patients who underwent interventional therapy in Department of Interventional Radiology, The First Affiliated Hospital of Soochow University, from January 2016 to December 2020 and had or were suspected of biliary tract infection, with samples submitted for bile culture and/or simultaneous blood culture. Analysis was performed for the aspects of positive rate of culture, flora distribution, consistency between blood culture and bile culture, and drug resistance rate of major pathogenic bacteria. Results A total of 219 patients were enrolled, among whom 105(47.95%) were positive for bile culture, and the composition ratios of Gram-negative bacteria, Gram-positive bacteria, and fungi were 64.89%, 28.24%, and 6.87%, respectively. A total of 69 patients had samples submitted for blood culture during the same period of time, among whom 33(47.82%) had positive results. Positive results of both bile culture and blood culture were observed in 25 patients, and consistency analysis showed that the patients with complete consistency, partial consistency, and complete inconsistency accounted for 36%(9/25), 20%(5/25), and 44%(11/25), respectively. Common Gram-negative bacteria were Escherichia coli , Klebsiella pneumoniae , and Enterobacter cloacae , with a relatively low level of drug resistance to antibiotics including cefoperazone/sulbactam, amikacin, and imipenem. Common Gram-positive bacteria were Enterococcus faecium and Enterococcus faecalis , with a relatively low level(< 15%) of drug resistance to antibiotics including vancomycin, linezolid, and teicoplanin. Conclusion Common pathogens of infection after percutaneous biliary drainage or stent implantation in MBO patients include Escherichia coli , Klebsiella pneumoniae , Enterococcus, and Enterobacter cloacae . There is a relatively low level of consistency between blood culture and bile culture, and thus samples should be submitted for both tests.

Association of clustered regularly interspaced short palindromic repeats with genotyping and drug-resistance genes of group B Streptococcus / 中华围产医学杂志

Objective:To investigate the distribution of clustered regularly interspaced short palindromic repeats (CRISPR) in group B Streptococcus (GBS) in the genital tract of women during the third trimester and in infants with invasive infection and its relationship with multilocus sequence typing (MLST) and drug-resistance genes. Methods:This study retrospectively collected 84 GBS strains isolated from pregnant women with GBS colonization and infants with invasive GBS infection who were admitted to Children's Hospital Affiliated to Shanxi Medical University from January 2017 to January 2022. CRISPR, MLST, and drug-resistance phenotype and genes were detected and analyzed using χ 2 test or Fisher exact probability method. MEGA11 was used to construct a dendrogram. Results:There were ten sequence typing in the 84 GBS strains and ST10 was the dominant one (46.4%). GBS was sensitive to penicillin, and its resistance rates to erythromycin (75.0%) and clindamycin (73.8%) were high. Among the 17 invasive GBS strains, ST10 had 100% resistance to erythromycin, clindamycin, and levofloxacin. CRISPR1 gene was amplified in 62 strains (73.8%). CRISPR1-positive strains had a significantly higher proportion of ST10 [56.5%(35/62) vs 18.2%(4/22), χ 2=9.56, P=0.002] and ermB, gyrA, parC [54.8%(34/62) vs 22.7%(5/22), 67.7%(42/62) vs 36.4%(8/22), 71.0%(44/62) vs 36.4%(8/22); χ 2=6.73, 6.64, and 8.25, all P<0.05], and a lower proportion of ermA [6.5%(4/62) vs 31.8%(7/22), χ 2=7.09, P=0.008] than CRISPR1-negative strains. Conclusions:ST10 is the main GBS genotype among the colonized microbiota the genital tract of pregnant women and in infants with invasive GBS infection, which is also a dominant type in CRISPR1-positive strains. GBS is sensitive to penicillin and CRISPR1 gene is linked to the spread of some drug-resistance genes.

Risk factors and prognosis analysis of carbapenem-resistant Klebsiella pneumoniae infection for inpatients in hepatobiliary surgery / 中华肝胆外科杂志

Objective:To explore the risk factors and prognosis of carbapenem-resistant Klebsiella pneumoniae (CRKP) infection for inpatients in hepatobiliary surgery. Methods:The clinical data of patients with Klebsiella pneumoniae infection admitted to the Department of Hepatobiliary Surgery, Hunan Provincial People's Hospital from January 2016 to December 2020 were retrospectively analyzed. For each patient with CRKP infection, two patients with non-carbapenem-resistant Klebsiella pneumoniae (non-CRKP) infection were selected for matching. A total of 720 patients with Klebsiella pneumoniae infection were involved, including 444 males and 276 females, aged (58.0±11.6) years old. According to the infection conditions, they were divided into two groups: CRKP group ( n=240) and non-CRKP group ( n=480). The 240 CRKP patients were divided into two subgroups according to their prognosis: death group ( n=34) and survival group ( n=206). The general information, laboratory test results, antibiotic use and infection outcomes of patients were recorded to analyze the risk factors of infection and death after infection. Results:Acute pancreatitis ( OR=3.473, 95% CI: 1.844-6.541), chronic cardiovascular disease before infection ( OR=2.028, 95% CI: 1.228-3.347), chronic renal failure ( OR=1.873, 95% CI: 1.142-3.073), hypoalbuminemia ( OR=3.060, 95% CI: 1.869-5.010), use of carbapenems ( OR=3.882, 95% CI: 2.518-5.985), admission to intensive care unit ( OR=1.783, 95% CI: 1.034-3.075) and surgery within 30 days before infection ( OR=13.463, 95% CI: 7.482-24.223) were independent risk factors for CRKP infection inpatients in hepatobiliary surgery(all P<0.05). Chronic respiratory disease before infection ( OR=3.784, 95% CI: 1.420-10.089), mechanical ventilation ( OR=5.085, 95% CI: 1.436-18.011), disturbance of consciousness ( OR=40.710, 95% CI: 3.564-464.943), hormone therapy ( OR=14.977, 95% CI: 3.819-58.743) and treatment of quinolone antibiotics ( OR=4.102, 95% CI: 1.226-13.726) were independent risk factors for death of inpatients with CRKP infection in hepatobiliary surgery (all P<0.05). The resistance of amikacin, tobramycin, ceftazidime, cefepime, aztreonam, ciprofloxacin, levofloxacin, co-sulfamethoxazole and piperacillin/tazobactamand in CRKP group were significantly different compared with non-CRKP group (all P<0.05). Conclusion:The occurrence of CRKP infection for inpatients in hepatobiliary surgery is related to various factors such as underlying diseases, antibiotic use and self-barrier destruction, and these factors affect the infection outcome of patients.

Ceftriaxone-resistant Neisseria gonorrhoeae strain FC428: prevalence, resistance mechanisms and control strategies / 中华皮肤科杂志

Antimicrobial resistance of Neisseria gonorrhoeae has become a big challenge in the control and prevention of sexually transmitted diseases. Recently, a ceftriaxone-resistant Neisseria gonorrhoeae strain FC428 has spread across the world including China, which has worsened the antimicrobial resistance problem. This strain is highly resistant to ceftriaxone due to a novel mosaic penA gene. In order to better understand the characteristics of FC428 and control its further spread, this review summarizes its origin, spread, main molecular characteristics, resistance mechanisms, detection methods, and strategies for clinical treatment and antimicrobial resistance surveillance.

Analysis of etiological characteristics and establishment of prediction model of postoperative infections in patients undergoing oral squamous cell carcinoma surgery with free flap reconstruction / 北京大学学报(医学版)

OBJECTIVE@#To investigate the characteristics of pathogen infection and to establish a prediction model of infections in oral squamous cell carcinoma patients undergoing surgery with free flap reconstruction.@*METHODS@#The retrospective cohort study consisted of 1 596 patients undergoing tumor resection and free flap reconstruction for oral squamous cell carcinoma from January 2018 to December 2020. According to the postoperative infection, the patients were divided into the infected group (n=154) and non-infected group (n=1 442). The characteristics of pathogens were analyzed in the infected patients. The primary outcome variable was postoperative infection, and Logistic regression was used to determine risk factors of the infection. The prediction model was established and the discriminatory accuracy of the model was evaluated using receiver operating characteristic (ROC) curve.@*RESULTS@#Totally 154 cases were infected in the 1 596 cases undergoing surgery with free flap reconstruction, and the infection rate was 9.65%. The most frequent sites of infection were the surgical wound and respiratory tract. A total of 268 pathogens were isolated and cultured, including 240 strains of Gram-negative bacteria, accounting for 89.55%, mainly Pseudomonas aeruginosa and Klebsiella pneumoniae; 23 strains of Gram-positive bacteria, accounting for 8.58%, mainly Enterococcus faecalis and Staphylococcus aureus; and 5 strains of fungi, accounting for 1.87%. The isolated Pseudomonas aeruginosa had high resistant rate to imipenem and meropenem, and was sensitive to antibiotics, such as ciprofloxacin. The isolated Staphylococcus aureus had high resistant rate to erythromycin and clindamycin, and was sensitive to vancomycin. According to the multivariate Logistic analysis, four independent variables were significantly associated with an increased risk of postoperative infection (P < 0.05): clinical N category≥1, the American Society of Anesthesiologists (ASA) grade ≥2, tracheotomy and length of hospital stay >13 d. The prediction model was established based on these factors and the expression of the risk prediction model was as follows: predicted probability value P=1/(1+e-a), a=-0.803+0.674×(clinical N category ≥1)+0.518×(the ASA grade ≥2)+0.918×(tracheotomy)+1.581×(length of hospital stay >13 d), Hosmer-Lemeshow χ2=10.647, P=0.223, the degree of fitting of the model was good. The area under the ROC curve was 0.818 and 95%CI of the model for predicting infection was 0.789-0.846.@*CONCLUSION@#Oral squamous cell carcinoma patients undergoing surgery with free flap reconstruction are prone to have a high incidence of postoperative infection and Gram-negative bacteria are the main pathogens causing an infection. The established prediction model is of good predictive effect. Rational antimicrobial use coupled with awareness of infection control measures is paramount to reduce the incidence of postoperative infection in the oral squamous cell carcinoma patients undergoing surgery with free flap reconstruction.

Estructura genética de cepas de Mycobacterium tuberculosis farmacorresistentes en Perú con base en haplotipos obtenidos de un ensayo de sonda lineal / Genetic structure of drug-resistant strains of Mycobacterium tuberculosis in Peru based on haplotypes obtained from a linear probe assay

RESUMEN Objetivo. Determinar la estructura genética de las cepas drogorresistentes de Mycobacterium tuberculosis que circularon en todo el Perú durante los años 2011-2015 a través de haplotipos obtenidos de un ensayo con sondas en línea. Materiales y métodos. Se analizaron 6589 muestras que ingresaron al Instituto Nacional de Salud para el diagnóstico rutinario mediante el ensayo GenoType® MTBDRplus v2, durante el periodo de estudio. Se crearon haplotipos resistentes mediante la concatenación de 21 sitios polimórficos de los genes evaluados por el ensayo con sondas en línea, y se realizó el análisis de asociación con fenotipos obtenidos por el método de proporciones agar 7H10. Resultados. Las mutaciones de mayores frecuencias fueron: rpoB S531L (55,4%) y rpoB D516V (18,5%) para la resistencia a rifampicina, y katG S315T (59,5%) e inhA c-15t (25,7%) para la resistencia a isoniacida. Se obtuvieron 13 haplotipos representativos (87,8% de muestras analizadas) de los cuales seis correspondieron al genotipo multidrogorresistente, cuatro al genotipo monorresistente a isoniacida y tres al genotipo monorresistente a rifampicina. Dieciocho departamentos, y la provincia del Callao, presentaron una alta diversidad haplotípica; cuatro presentaron moderada diversidad y dos presentaron baja diversidad. Conclusiones. Existe una alta diversidad haplotípica en la mayoría de los departamentos, además de una concentración de las cepas de Mycobacterium tuberculosis drogorresistentes en las ciudades de Lima y Callao. Asimismo, las cepas de Mycobacterium tuberculosis con perfil drogorresistente que circulan en el Perú contienen principalmente los marcadores genéticos de mayor prevalencia a nivel mundial asociados con la resistencia frente a rifampicina e isoniacida.

ABSTRACT Objective. To determine the genetic structure of drug-resistant strains of Mycobacterium tuberculosis that circulated throughout Peru during the years 2011-2015, by using haplotypes obtained from a line probe assay. Materials and methods. A total of 6589 samples that were admitted to the Instituto Nacional de Salud for routine diagnosis using the GenoType® MTBDRplus v2 assay were analyzed during the study period. Resistant haplotypes were created by concatenating 21 polymorphic sites of the evaluated genes using the line probe assay; and the association analysis was carried out with phenotypes obtained by the 7H10 agar ratio method. Results. The most frequent mutations were: rpoB S531L (55.4%) and rpoB D516V (18.5%) for rifampicin resistance, and katG S315T (59.5%) and inhA c-15t (25.7%) for isoniazid resistance. We obtained 13 representative haplotypes (87.8% of analyzed samples), 6 corresponded to the multidrug-resistant genotype, 4 to the isoniazid mono-resistant genotype and 3 to the rifampicin mono-resistant genotype. Eighteen regions and the province of Callao showed high haplotype diversity; four showed moderate diversity and two showed low diversity. Conclusions. Most regions showed high haplotype diversity; in addition, most drug-resistant strains of Mycobacterium tuberculosis were concentrated in the cities of Lima and Callao. Likewise, drug-resistant Mycobacterium tuberculosis strains circulating in Peru mainly contain the genetic markers with the highest prevalence worldwide, which are associated with resistance to rifampicin and isoniazid.

Caracterización de la tuberculosis multidrogorresistente y resistente a rifampicina en Colombia / Characterization of rifampin-resistant/multidrug-resistant tuberculosis in Colombia

RESUMEN Objetivo Caracterizar la población afectada por tuberculosis multidrogorresistente y resistente a rifampicina (TB-MDR/RR) en Colombia. Métodos Estudio transversal a partir de la información nominal de los pacientes con TB-MDR/RR tratados y reportados en Colombia desde 2009 hasta 2020, usando la totalidad de las fuentes de información oficiales. Se compararon, además, las tasas de TB-MDR/RR de diferentes grupos de riesgo con la de la población general y se evaluaron variables asociadas a la TB-MDR/RR extrapulmonar y a resistencias medicamentosas. Resultados La TB-MDR/RR ha aumentado progresivamente durante la última década y se ha concentrado en hombres (64% vs. 36%, p<0,001), edades medias (mediana: 39,5 años; RIC: 27) y zonas de mayor densidad poblacional (59% de los casos en Antioquia, Valle del Cauca y Santiago de Cali). Además, al compararlas con las poblaciones de referencia que aplicaran, se evidenciaron tasas 2, 10 y 200 veces mayores en población indígena (9,45/1 000 000 vs. 4,31/1 000 000; p=0,02), prisioneros (169/1 000 000 vs. 16,9/1 000 000; p<0,001) y habitantes de calle (21/100000 vs. 0,1/100 000; p<0,001), respectivamente. Conclusiones El aumento en los casos de TB-MDR/RR y sus grupos de riesgo deben tenerse en cuenta para la planeación de políticas, distribución de recursos y atención clínica.

ABSTRACT Objective To describe the population affected by rifampin-resistant/multidrug-resistant tuberculosis (RR/MDR-TB) in Colombia. Methods Cross-sectional study on all the patients treated for RR/MDR-TB in Colombia between 2009 and 2020, using all the official sources of information. In addition, a comparison was made between the rates of RR/MDR-TB in some higher-risk groups and average population. Finally, the variables associated to pulmonary versus extrapulmonary RR/MDR-TB and those associated to resistance to other drugs were evaluated. Results RR/MDR-TB cases have progressively increased during the last decade. These cases were concentrated in men (64% vs. 36%, p<0.001), middle aged adults (median: 39.5 years old; IQR: 27), and in geographic regions with higher population density (59% of cases in Antioquia, Valle del Cauca and Santiago de Cali). Also, the rate of RR/MDR-TB was 2, 10 and 200 times higher in indigenous (9.45/1 000 000 vs. 4.31/1 000 000; p=0.02), prisoners (169/1 000 000 vs. 16.9/1 000 000; p<0.001), and homeless population (21/100 000 vs. 0.1/100 000; p<0.001), respectively. Conclusions The increase in RR/MDR-TB cases and their concentration in higher-risk groups must be kept in mind to make better policies, a more efficient distribution of resources, and better patient care.