Frecuencia de E. coli y Klebsiella spp productoras de betalactamasas en cultivos procesados en un laboratorio clínico / Frequency of E. coli and betalactamase-producing Klebsiella spp in cultures processed in a clinical laboratory / Frequência de E. coli e Klebsiella spp produtoras de betalactamase em culturas processadas em laboratório clínico

Introducción: la resistencia antibiótica en bacterias patógenas como Escherichia coli y Klebsiella spp. productoras de betalactamasas, han surgido como un problema global de salud pública. Su presencia, se asocia con infecciones intrahospitalarias y comunitarias, aumentando la morbilidad y la mortalidad de los pacientes. Objetivo: determinar la frecuencia de E.coli y Klebsiella spp productoras de betalactamasas en cultivos procesados en un laboratorio clínico. Métodos: se realizó un estudio descriptivo de diseño documental. La muestra estuvo constituida por un total de 1465 resultados de cultivos positivos para Escherichia coli o Klebsiella spp. en el periodo 2022. Para la recolección de la información, se tuvo acceso a la base de datos anonimizada del laboratorio en una hoja de Excel para su posterior análisis. Los datos fueron tabulados en SPSS versión 25. Resultados: el análisis de bacterias productoras de BLEE mostró una positividad del 22,3% en E. coli y 46,1% en Klebsiella spp. E. coli presentó mayor frecuencia de negativos (77,7%) en comparación con Klebsiella spp. La presencia de E. coli fue más común en muestras de orina (90,6%) y en otras muestras como esputo y heridas cutáneas (21,3%). Se evaluaron 8 antibióticos, y se destacó la alta sensibilidad para amikacina (AK) (99,6% y 98,0%) y elevada resistencia ampicilina (AM) (91,5% y 100%) en ambas especies. Ciprofloxacino (CIP) y Trimetropin/Sulfametoxazol (STX) mostraron relativa frecuencia mayor de resistencia. Conclusión: los resultados muestran una alta frecuencia de bacterias productoras de BLEE en E. coli y Klebsiella spp., con una mayor prevalencia en Klebsiella spp. Además, la resistencia a AM, CIP y STX destaca la importancia de una gestión adecuada de la resistencia antimicrobiana.

Introduction: antibiotic resistance in pathogenic bacteria such as Escherichia coli and Klebsiella spp. producing beta-lactamases has emerged as a global public health problem. Their presence has been associated with both hospital-acquired and community-acquired infections, leading to increased morbidity and mortality in patients. Objective: to determine the frequency of betalactamase-producing E. coli and Klebsiella spp. in cultures processed in a clinical laboratory. Methods: a descriptive documentary design study was conducted. The sample consisted of a total of 1465 positive culture results for Escherichia coli or Klebsiella spp. in the year 2022. Data collection involved accessing the laboratory's anonymized database in an Excel sheet for subsequent analysis. The data were tabulated in SPSS version 25. Results: the analysis of ESBL-producing bacteria showed a positivity of 22.3% in E. coli and 46.1% in Klebsiella spp. E. coli showed a higher frequency of negatives (77.7%) compared to Klebsiella spp. The presence of E. coli was more common in urine samples (90.6%) and in other samples such as sputum and skin wounds (21.3%). Eight antibiotics were evaluated, with high sensitivity noted for amikacin (AK) (99.6% and 98.0%) and high resistance for ampicillin (AM) (91.5% and 100%) in both species. Ciprofloxacin (CIP) and Trimethoprim/Sulfamethoxazole (STX) showed a relatively higher frequency of resistance. Conclusion: the results show a high frequency of ESBL-producing bacteria in E. coli and Klebsiella spp., with a higher prevalence in Klebsiella spp. Furthermore, the resistance to AM, CIP, and STX highlights the importance of proper management of antimicrobial resistance.

Introdução: a resistência antibiótica em bactérias patogênicas como Escherichia coli e Klebsiella spp., produtoras de beta-lactamases, emergiu como um problema de saúde pública global. Sua presença tem sido associada a infecções hospitalares e comunitárias, aumentando a morbidade e a mortalidade dos pacientes. Objetivo: determinar a frequência de E. coli e Klebsiella spp. produtoras de betalactamase em culturas processadas em laboratório clínico. Métodos: foi realizado um estudo descritivo de design documental. A amostra consistiu em um total de 1465 resultados de cultura positiva para Escherichia coli ou Klebsiella spp. no ano de 2022. A coleta de dados envolveu o acesso ao banco de dados anonimizado do laboratório em uma planilha do Excel para análise subsequente. Os dados foram tabulados na versão 25 do SPSS. Resultados: a análise de bactérias produtoras de BLEE mostrou uma positividade de 22,3% em E. coli e 46,1% em Klebsiella spp. E. coli apresentou uma frequência maior de resultados negativos (77,7%) em comparação com Klebsiella spp. A presença de E. coli foi mais comum em amostras de urina (90,6%) e em outras amostras, como escarro e feridas na pele (21,3%). Foram avaliados oito antibióticos, com alta sensibilidade observada para amicacina (AK) (99,6% e 98,0%) e alta resistência para ampicilina (AM) (91,5% e 100%) em ambas as espécies. Ciprofloxacina (CIP) e Trimetoprima/Sulfametoxazol (STX) mostraram uma frequência relativamente maior de resistência. Conclusão: os resultados mostram uma alta frequência de bactérias produtoras de BLEE em E. coli e Klebsiella spp., com uma maior prevalência em Klebsiella spp. Além disso, a resistência a AM, CIP e STX destaca a importância da adequada gestão da resistência antimicrobiana.

Caracterización molecular de Escherichia coli diarreogénica proveniente de población pediátrica ambulatoria con diarrea, atendida en dos hospitales de Buenos Aires, Argentina / Molecular characterization of diarrheagenic Escherichia coli from an outpatient pediatric population with diarrhea attended in two hospitals from Buenos Aires, Argentina

Resumen Escherichia coli diarreogénica abarca un grupo heterogéneo de patotipos o variantes patogénicas que comparten características fenotípicas con marcadas diferencias en genes de virulencia, sitios de colonización, patogenia, presentación clínica y epidemiología de la infección. Los patotipos más estudiados son E.coli productora de toxina Shiga (STEC), E.coli enterotoxigénica (ETEC), E.coli enteropatogénica (EPEC), E.coli enteroagregativa (EAEC) y E.coli enteroinvasiva (EIEC). El objetivo del estudio fue caracterizar los aislamientos de E.coli diarreogénica provenientes de población pediátrica ambulatoria con diarrea, atendida en dos hospitales públicos de Buenos Aires, Argentina. Los patotipos de E.coli diarreogénica se investigaron mediante la amplificación de fragmentos de genes de virulencia característicos: intimina (eae), toxina termolábil (lt), toxinas termoestables (stp, sth), antígeno plasmídico de invasiónH (ipaH), activador transcripcional R (aggR) y toxinas Shiga (stx1, stx2). La subtipificación molecular de aislamientos se realizó mediante PFGE (XbaI). E.coli diarreogénica fue detectada en el 14% (84/601) de los casos. El patotipo EAEC fue prevalente, mientras que ETEC, STEC, EPEC y EIEC fueron hallados en menor proporción. Los aislamientos de EAEC presentaron un alto grado de diversidad genética. Todos los patotipos fueron hallados en niños menores de 5años, mientras que solamente EAEC, EIEC y ETEC fueron detectados en población de mayor edad. Futuros estudios que incluyan la caracterización de aislamientos a partir de un mayor número de genes y población de otras áreas geográficas serán necesarios para determinar la relevancia de E.coli diarreogénica en Argentina.

Abstract Diarrheagenic Escherichia coli comprises a heterogeneous group of pathotypes or pathogenic variants that share phenotypic characteristics with marked differences in virulence genes, colonization sites, pathogenesis, clinical presentation, and epidemiology of infection. The most studied pathotypes are Shiga toxin-producing E.coli (STEC), enterotoxigenic E.coli (ETEC), enteropathogenic E.coli (EPEC), enteroaggregative E.coli (EAEC), and enteroinvasive E.coli (EIEC). The objective of the study was to characterize the isolates of diarrheagenic E.coli from an outpatient pediatric population with diarrhea attended in two public hospitals from Buenos Aires, Argentina. Diarrheagenic E.coli pathotypes were investigated by amplifying characteristic virulence gene fragments: intimin (eae), heat-labile toxin (lt), heat-stable toxins (stp, sth), invasion plasmid antigen H (ipaH), transcriptional activator R (aggR) and Shiga toxins (stx1, stx2). Molecular subtyping of isolates was performed using PFGE (XbaI). Diarrheagenic E.coli was detected in 14% (84/601) of cases. The EAEC pathotype was prevalent, while ETEC, STEC, EPEC and EIEC were found in a lower proportion. EAEC isolates exhibited a high degree of genetic diversity. All pathotypes were found in children under 5years of age, while only EAEC, EIEC and ETEC were detected in the older population. Future studies that include the characterization of isolates from a greater number of genes and populations from other geographical areas will be necessary to determine the relevance of diarrheagenic E.coli in Argentina.

Detection of plasma anti-lipopolysaccharide (LPS)antibodies against enterohemorrhagic Escherichia coli(EHEC) in asymptomatic kindergarten teachers fromBuenos Aires province

Resumen En Argentina, el síndrome urémico hemolítico causado por Escherichia coli enterohemorrágica (EHEC) tiene la más alta incidencia del mundo. Las infecciones por EHEC tienen un comportamiento endemoepidémico y causan del 20 al 30% de los síndromes de diarrea sanguinolenta en niños menores de 5 años. En el período 2016-2020, se notificaron 272 nuevos casos por año al Sistema de Vigilancia de Salud Nacional. Múltiples factores son responsables de la alta incidencia de SUH en Argentina, incluyendo la transmisión persona-persona. Con el objetivo de detectar posibles portadores asintomáticos de EHEC, realizamos un estudio preliminar de la frecuencia de anticuerpos antilipopolisacáridos contra los serotipos de EHEC más prevalentes en Argentina. El estudio se realizó con muestras de plasma obtenidas de 61 maestras y maestros de jardines de infantes de 26 instituciones del distrito de José C. Paz, localizado en el área suburbana de la provincia de Buenos Aires, Argentina. El 51% de las muestras presentaron anticuerpos contra los serotipos de lipopolisacáridos O157, O145, O121 y O103; el 6,4% de las muestras positivas tuvieron el isotipo IgM (n=2), el 61,3% el isotipo IgG (n=19) y el 32,3% los isotipos IgM e IgG (n=10). Dado que los anticuerpos antilipopolisacáridos presentan usualmente una duración corta, la detección de IgM específica podría indicar una infección reciente. Además, el alto porcentaje de muestras positivas hallado podría indicar una exposición frecuente a las cepas de EHEC en la cohorte estudiada. Asimismo, la gran población de adultos portadores asintomáticos de estas cepas patógenas podría contribuir al comportamiento endémico, a través de la transmisión persona-persona. El perfeccionamiento de programas educacionales continuos en jardines de infantes podría constituir una medida importante para reducir los casos de síndrome urémico hemolítico, no solo en Argentina, sino también en el mundo.

Abstract In Argentina, hemolytic uremic syndrome (HUS) caused by EHEC has the highest incidence in the world. EHEC infection has an endemo-epidemic behavior, causing 20-30% of acute bloody diarrhea syndrome in children under 5 years old. In the period 2016-2020, 272 new cases per year were notified to the National Health Surveillance System. Multiple factors are responsible for HUS incidence in Argentina including person-to-person transmission. In order to detect possible EHEC carriers, we carried out a preliminary study of the frequency of kindergarten teachers with anti-LPS antibodies against the most prevalent EHEC serotypes in Argentina. We analyzed 61 kindergarten teachers from 26 institutions from José C. Paz district, located in the suburban area of Buenos Aires province, Argentina. Fifty-one percent of the plasma samples had antibodies against O157, O145, O121 and O103 LPS: 6.4% of the positive samples had IgM isotype (n=2), 61.3% IgG isotype (n=19) and 32.3% IgM and IgG (n=10). Given that antibodies against LPS antigens are usually short-lived specific IgM detection may indicate a recent infection. In addition, the high percentage of positive samples may indicate a frequent exposure to EHEC strains in the cohort studied, as well as the existence of a large non-symptomatic population of adults carrying pathogenic strains that could contribute to the endemic behavior through person-to-person transmission. The improvement of continuous educational programs in kindergarten institutions could be a mandatory measure to reduce HUS cases not only in Argentina but also globally.

Development and verification of an ELISA method for detection of process-specific residual host protein in biological preparation / 中国生物制品学杂志

@#Objective To develop and verify a double-antibody sandwich ELISA method for the detection of process-specific E.coli residual protein in recombinant biological preparations.Methods Taking the production and purification process of glucagon-like peptide(GLP)expressed by E.coli as the specific process model,the same process was used to intercept the residual protein of empty E.coli(normal E.coli that does not express recombinant protein). One female New Zealand white rabbit and six female Kunming mice were immunized with the residual protein as the immunogen. Using the IgG antibody purified from rabbit immune serum as the coating antibody,mouse immune serum as the second sandwich antibody,and antimouse IgG-HRP as the enzyme-labeled secondary antibody,a double antibody sandwich ELISA method for process-specific residual protein of E.coli was established. The specificity,accuracy and precision of the method were verified,and the limit of detection(LOD)was determined. Simultaneously,the developed method and the commercial E.coli host protein residue detection kit were used to quantitatively determine the residual protein of purified GLP preparation.Results After a series of gradient dilution of process-specific residual protein with known concentration,the sensitivity of this ELISA method reached 338 pg/mL. No cross reaction occurred in the detection of CHO and yeast cell lysis protein by this method,the recoveries of samples with low,medium and high concentrations were all in the range of 80% — 120%,and the intra-assay and inter-assay CVs of the empty E.coli interception standard with low,medium and high concentrations were all less than15%. For the residual protein in GLP preparation,about 62% of the residual proteins were not detected by the commercial non-process-specific ELISA kit compared with the total amount of residual proteins detected by the developed method,and these residual proteins should be the process-specific residual proteins.Conclusion The double antibody sandwich ELISA method developed in this study has high sensitivity,strong specificity,good accuracy and precision for the detection of process-specific E.coli residual protein,which can meet the detection requirements that the residual protein is less than0. 01% — 0. 1% in biological preparations.

Hospitalizaciones por diarrea con sangre en un centro pediátrico de referencia en Uruguay

Introducción: La diarrea con sangre es un motivo frecuente de admisión hospitalaria en niños, con gastroenteritis aguda; en la mayoría de los casos se tratan de infecciones leves y autolimitadas, pero pueden producirse complicaciones graves. Objetivos: Describir la etiología y características clínico- evolutivas de los niños menores de 15 años hospitalizados por diarrea con sangre en el Hospital Pediátrico, Centro Hospitalario Pereira Rossell entre los años 2012- 2023. Materiales y métodos: Estudio retrospectivo mediante revisión de historias y registros de laboratorio. Variables: demográficas, estado nutricional, hidratación, motivos de hospitalización, ingreso unidades de cuidados intensivos (UCI), enteropatógenos, tratamientos, evolución. Resultados: Se incluyeron 229 niños, mediana de edad de 8 meses; sexo masculino 61%; eutróficos 88%, bien hidratados 55%, con comorbilidades 11%, prematurez 6,5%. El motivo de hospitalización fue diarrea con sangre/disentería sin otro síntoma 45%. Se solicitó coprovirológico/coprocultivo en 98% y detección por técnicas de ácidos nucleicos en materia fecal 5,2%. Se identificó al menos un agente patógeno en 34,3%: Shigella sp. 38%; Salmonella sp. 19,5%; coinfecciones en 12%. Se indicaron antibióticos a 86%; ceftriaxona 62%, azitromicina 35%. Ingresaron a UCI 6,5% (15), presentaron complicaciones 10/14, fallo renal agudo 5 y alteraciones del medio interno 3. La mayoría presentó buena evolución. Conclusiones: La diarrea con sangre/disentería continúa siendo una causa importante de hospitalización afectando en su mayoría a niños sanos menores de 5 años. Los patógenos detectados con mayor frecuencia fueron bacterias principalmente Shigella sp., Salmonella sp. y E coli diarreogénicas. Se reportó alta prescripción de antibióticos, cumpliendo en la mayoría de los casos con las recomendaciones.

Introduction: Bloody diarrhea is a common reason for hospital admission in children with acute gastroenteritis; In most cases these are mild and self-limiting infections, but serious complications can occur. Goals: To describe the etiology and clinical-evolutionary characteristics of children under 15 years of age hospitalized for bloody diarrhea at the Pediatric Hospital, Centro Hospitalario Pereira Rossell between the years 2012-2023. Materials and methods: Retrospective study through review of histories and laboratory records. Variables: demographics, nutritional status, hydration, reason for hospitalization, intensive care unit (ICU) admission, enteropathogens, treatments, evolution. Results: 229 children were included, median age 8 months; male sex 61%; eutrophic 88%, well hydrated 55%, with comorbidities 11%, prematurity 6.5%. The reason for hospitalization was bloody diarrhea/dysentery without other symptoms 45%. Coprovirological/coproculture was requested in 98% and detection by nucleic acid techniques in fecal matter was requested in 5,2%. At least one pathogenic agent was identified in 34,3%: Shigella sp. 38%; Salmonella sp 19,5%; coinfections in 12%. Antibiotics were indicated for 86%; ceftriaxone 62%, azithromycin 35%. Were admitted to the ICU 6,5% (15), 10/14 had complications, 5 had acute kidney failure and 3 had alterations in the internal environment. The majority had a good evolution. Conclusions: Bloody diarrhea/dysentery continues to be an important cause of hospitalization, affecting mostly healthy children under 5 years of age. The most frequently detected pathogens were bacteria, mainly Shigella sp., Salmonella sp. and diarrheagenic E coli. High prescription of antibiotics was reported, complying in most cases with the recommendations.

Introdução: A diarreia com sangue é um motivo comum de internação hospitalar em crianças com gastroenterite aguda; Na maioria dos casos, estas são infecções leves e autolimitadas, mas podem ocorrer complicações graves. Metas: Descrever a etiologia e as características clínico-evolutivas de crianças menores de 15 anos internadas por diarreia sanguinolenta no Hospital Pediátrico Centro Hospitalario Pereira Rossell entre os anos de 2012-2023. Materiais e métodos: Estudo retrospectivo por meio de revisão de histórias e registros laboratoriais. Variáveis: dados demográficos, estado nutricional, hidratação, motivo da internação, internação em unidade de terapia intensiva (UTI), enteropatógenos, tratamentos, evolução. Resultados: foram incluídas 229 crianças, mediana de idade 8 meses; sexo masculino 61%; eutrófico 88%, bem hidratado 55%, com comorbidades 11%, prematuridade 6,5%. O motivo da internação foi diarreia sanguinolenta/disenteria sem outros sintomas 45%. O estudo coprovirologico/coprocultivo foi solicitado em 98% e a detecção por técnicas de ácidos nucleicos em matéria fecal foi solicitada em 5,2%. Pelo menos um agente patogênico foi identificado em 34,3%: Shigella sp. 38%; Salmonella sp. 19,5%; coinfecções em 12%. Os antibióticos foram indicados para 86%; ceftriaxona 62%, azitromicina 35%. Foram internados em UTI 6,5% (15), 10/14 apresentaram complicações, 5 tiveram insuficiência renal aguda e 3 apresentaram alterações no meio interno, a maioria teve boa evolução. Conclusões: A diarreia/disenteria com sangue continua a ser uma causa importante de hospitalização, afetando sobretudo crianças saudáveis ​​com menos de 5 anos de idade. Os patógenos mais frequentemente detectados foram bactérias, principalmente Shigella sp., Salmonella sp. e E. coli diarreiogênica. Foi relatada elevada prescrição de antibióticos, cumprindo na maioria dos casos as recomendações.

Endogenous endophthalmitis due to Escherichia coli: a case report

ABSTRACT Endophthalmitis is a severe form of purulent inflammation caused by the infection of the intraocular tissues or fluids. This infection infrequently occurs through endogenous routes, which are often correlated with major risk factors. Escherichia coli, a gram-negative rod, can cause endophthalmitis through hematogenous spread. We here report a 59-year-old man who presented to our service with acute visual impairment in his left eye, preceded by floaters. He was taking sirolimus and azathioprine for a transplanted kidney, had undergone catheterization for bladder atresia, and had a history of recurrent E. coli urinary tract infections. On evaluation, the left eye exhibited visual acuity of hand motion, anterior chamber reaction (3+/4+), and intense vitritis (4+/4+) with white flake clusters, which prevented appropriate retinal evaluation. Pars plana vitrectomy was performed, and the culture yielded E. coli. The present case highlights the importance of identifying the signs and symptoms of infection early so that diagnosis and treatment of endophthalmitis can be promptly initiated.

In vitro susceptibility to fosfomycin in clinical and environmental extended-spectrum beta-lactamase producing and/or ciprofloxacin-non-susceptible Escherichia coli isolates

ABSTRACT Extended-spectrum beta-lactamase producing and ciprofloxacin-non-susceptible Escherichia coli are clinical and environmental issues. We evaluated the susceptibility profile of fosfomycin in non-susceptible E. coli isolated from urine and the environment. We measured the activity of fosfomycin against 319 and 36 E. coli strains from urine and environmental isolates, respectively, collected from rivers. Fosfomycin resistance profiles were investigated using the minimal inhibitory concentration (MIC), according to the Clinical and Laboratory Standards Institute (CLSI) and the European Committee for Antimicrobial Susceptibility Testing (EUCAST) guidelines. Antibiotic susceptibility testing revealed that 5% and 6.6% of urine samples were non-susceptible to fosfomycin according to CLSI and EUCAST guidelines, respectively. The fosfomycin MIC50/90 was 0.5/4 mg/L. Of the 36 E. coli isolates from river water, 11.1% and 13,8% were non-susceptible to fosfomycin according to CLSI and EUCAST, respectively (range ≤0.25 ≥512 mg/L). All the isolates with MIC ≥512 mg/L for fosfomycin showed the fosA3 gene. Fosfomycin resistance was more frequent in the environment than in clinical samples.

Síntesis de glicoconjugados de albúmina sérica bovina y oligosacáridos de quitosano para el análisis de adhesión bacteriana / Synthesis of glycoconjugates of bovine albumin and chitosan oligosaccharides for the analysis of bacterial adhesion / Síntese de glicoconjugados de albumina serica bovina e oligossacarídeos de quitosana para análise de adesão bacteriana

Resumen El aumento de la resistencia a los antibióticos por parte de bacterias patógenas ha motivado la búsqueda de alternativas para disminuir su utilización. Dentro de las opciones propuestas se encuentra la terapia de antiadherencia, en la cual se utilizan moléculas análogas a los glicoepítopes que son reconocidos por las bacterias para impedir la unión de éstas al tejido celular. En este estudio se llevó a cabo la obtención de glicoconjugados por medio de la reacción de Maillard partiendo de albúmina sérica bovina (BSA) y oligosacáridos de quitosano (oligosacáridos sin ultrafiltrar, ultrafiltrados y ultrafiltrados acetilados), en proporción 1:1 (p/p) a tres temperaturas de incubación (50, 60 y 70 °C) por 30 min. La caracterización de los conjugados sintetizados se realizó utilizando electroforesis (SDS-PAGE), espectroscopía de infrarrojo y espectroscopía de fluorescencia. Se realizaron ensayos de reconocimiento usando aglutinina de germen de trigo (WGA) y bacterias [Escherichia coli (K88ac y K88+)]. La caracterización por medio de electroforesis y espectroscopía de infrarrojo evidenció la unión de los oligosacáridos de quitosano a la estructura de la BSA. Además, los ensayos evidenciaron el reconocimiento de las moléculas sintetizadas tanto por la lectina WGA como por las bacterias. Los glicoconjugados sintetizados sin ultrafiltrar ni acetilar mostraron resultados muy favorables en el reconocimiento por ambas bacterias, lo que constituye una ventaja práctica, ya que su implementación a mayor escala reduciría costos de producción

Abstract The increase in antibiotic resistance by pathogenic bacteria has motivated the search for alternatives to reduce the use of antibiotics. Among these alternatives is anti-adhesion therapy, in which molecules that mimic the glycoepitopes that recognise bacteria are used to prevent their binding to cellular tissue. In this study, glycoconjugates were obtained by means of the Maillard reaction starting from bovine serum albumin (BSA) and chitosan oligosaccharides (unfiltered oligosaccharides, ultrafiltered and acetylated ultrafiltered), in a ratio of 1:1 (w/w) at three incubation temperatures (50, 60 and 70 °C) per 30 min. The characterisation was performed using the techniques of electrophoresis (SDS-PAGE), infrared spectroscopy and fluorescence spectroscopy. Recognition assays were performed using wheat germ agglutinin (WGA) and Escherichia coli bacteria (K88ac and K88+). Characterisation by electrophoresis and infrared spectroscopy demonstrated the binding of chitosan oligosaccharides to the structure of BSA. In addition, the tests showed the recognition of the molecules synthesised by both the WGA lectin and the E. coli bacteria. The glycoconjugates synthesised without ultrafiltration or acetylation showed very favourable results in recognition with both bacteria, which is an advantage, since its implementation on a larger scale would reduce production costs.

Resumo O aumento da resistência aos antibióticos por bactérias patogênicas tem motivado a busca de alterna­tivas para reduzir seu uso. Entre essas alternativas está a terapia anti-adesão, na qual são utilizadas moléculas análogas aos glicoepítopos que são reconhecidas pelas bactérias para impedir sua união ao tecido celular. Neste estudo, os glicoconjugados foram obtidos por meio da reação de Maillard a partir de albumina sérica bovina (BSA) e oligossacarídeos de quitosana (oligossacarídeos não ultra­filtrados, ultrafiltrados e acetilados ultrafiltrados), na proporção de 1:1 (p/p) em três temperaturas de incubação (50, 60 e 70 °C) durante 30 min. A caracterização dos conjugados sintetizados foi realizada utilizando a eletroforese (SDS-PAGE), espectroscopia de infravermelho e espectroscopia de fluorescência. Os ensaios de reconhecimento foram realizados utilizando aglutinina de germe de trigo (WGA) e bactérias [Escherichia coli (K88ac e K88+)]. A caracterização por meio de eletroforese e espectroscopia de infravermelho demonstrou a união dos oligossacarídeos de quitosana à estrutura da BSA. Além disso, os testes evidenciaram o reconhecimento das moléculas sintetizadas tanto pela lectina WGA quanto pelas bactérias. Os glicoconjugados sintetizados sem ultrafiltração ou acetilação apresentaram resultados muito favoráveis no reconhecimento por ambas as bactérias, o que é uma vantagem, visto que sua implementação em maior escala reduziria custos de produção.

Aceite esencial de Arazá (Eugenia stipitata McVaugh) con actividad antibacteriana

Introducción: El Perú es uno de los países con mayor biodiversidad en especies botánicas, algunas con propiedades medicinales conocidas. Objetivo: Determinar el efecto antibacteriano del aceite esencial de las hojas de Eugenia stipitata McVaugh frente a Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 y Salmonella enterica sv Enteritidis ATCC 13076. Métodos: Estudio de tipo básico con enfoque cuantitativo y experimental. Las plantas provienen del distrito de Belén, ciudad de Iquitos, Departamento de Loreto. La técnica para la extracción del aceite esencial fue la de arrastre de vapor y la técnica microbiológica para determinar el efecto antimicrobiano la de Kirby Bauer. Se trabajaron las muestras en 4 concentraciones 100, 75, 50 y un 25 %; un control negativo solo con dimetilsulfóxido, se utilizaron 5 repeticiones por cada muestra. Resultados: La muestra a concentración al 100 % tuvo actividad antibacteriana contra Staphylococcus aureus. La actividad del ensayo frente a Escherichia coli demostró ser efectiva en todas las muestras, sin embargo, se observó que los halos de inhibición de mayor diámetro se manifestaron en las muestras al 100 % y 75 %. Además, se evidenció actividad antibacteriana a concentraciones del 100 %, 75 % y un 50 % frente a Salmonella enterica sv Enteritidis. Conclusiones: El aceite esencial de las hojas de Eugenia stipitata McVaugh presenta efecto antibacteriano frente a Staphylococcus aureus, Escherichia coli y Salmonella enterica sv Enteritidis.

Introduction: Peru is one of the countries with the greatest biodiversity in botanical species, some with known medicinal properties. Objective: To determine the antibacterial effect of the essential oil of Eugenia stipitata McVaugh leaves against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Salmonella enterica sv Enteritidis ATCC 13076. Methods: Basic study with a quantitative and experimental approach. Plants came from the district of Belén, city of Iquitos, Department of Loreto. The technique for the extraction of the essential oil was steam dragging and the microbiological technique to determine the antimicrobial effect was Kirby Bauer's technique. The samples were worked in 4 concentrations 100, 75, 50 and 25 % and a negative control only with dimethyl sulfoxide, using 5 replicates for each sample. Results: The sample at 100 % concentration had antibacterial activity against Staphylococcus aureus. The activity of the assay against Escherichia coli proved to be effective in all the samples, however, it was observed that the inhibition halos of greater diameter were manifested in the samples at 100 % and 75 %. In addition, antibacterial activity was evidenced at concentrations of 100 %, 75 % and 50 % against Salmonella enterica sv Enteritidis. Conclusions: The essential oil of Eugenia stipitata McVaugh leaves has an antibacterial effect against Staphylococcus aureus, Escherichia coli and Salmonella enterica sv Enteritidis.

First report of the prevalence of Shiga toxinproducing Escherichia coli in ground beef in Quindío, Colombia

Introduction. Shiga toxin-producing Escherichia coli (STEC) is a foodborne pathogen associated with clinical cases of diarrhea in humans. Its main virulence factors are the Shiga toxins (Stx1 and Stx2). Cattle are the main reservoir of STEC, and many outbreaks in humans have been related to the consumption of undercooked ground beef contaminated with this pathogen. Objective. To determine the prevalence of STEC in ground beef commercialized in all the butcher shops of a township in the department of Quindío and to characterize the virulence genes of the strains found. Materials and methods. Thirty ground beef samples were taken in three different times; stx genes and other STEC virulence factors (eae, ehxA, saa) were detected by multiplex PCR. Results. The overall prevalence of STEC was 33.33 % (10/30 positive samples). We isolated eight non-O157 (LEE-negative) strains with four different genetic profiles: stx 2 / stx 2-ehxA-saa / stx 1-stx 2-ehxA-saa / stx 1-saa. Conclusion. This is the first report on the prevalence of STEC in ground beef in a township in the department of Quindío.

Introducción. Escherichia coli productora de toxina Shiga (STEC) es un agente patógeno de origen alimentario asociado a casos clínicos de diarrea en humanos; sus principales factores de virulencia son las toxinas Shiga (Stx1 y Stx2). El principal reservorio de STEC es el ganado bovino y muchos brotes en humanos se han relacionado con el consumo de carne mal cocida contaminada con este agente patógeno. Objetivo. El objetivo de este trabajo fue determinar la prevalencia de STEC en carne molida comercializada en todas las carnicerías de un municipio del departamento del Quindío y caracterizar los genes de virulencia de las cepas encontradas. Materiales y métodos. Se tomaron 30 muestras de carne molida en tres momentos diferentes; se detectaron los genes stx y otros factores de virulencia de STEC (eae, ehxA, saa) mediante PCR Multiplex. Resultados. Los resultados mostraron una prevalencia global de STEC del 33,33 % (10/30 muestras positivas). En total se aislaron ocho cepas STEC no-O157 (LEE-negativas) con cuatro perfiles genéticos diferentes: stx 2 / stx 2-ehxA-saa / stx 1-stx 2-ehxA-saa / stx 1-saa. Conclusión. Este es el primer reporte que muestra la prevalencia de STEC en carne molida en un municipio del departamento del Quindío.

Variables epidemiológicas y clínicas en pacientes pediátricos hospitalizados por infección del tracto urinario

Fundamento la infección del tracto urinario es una de las enfermedades más frecuentes en edades pediátricas y se presenta con sintomatología no específica, en especial en los niños más pequeños, en los cuales el signo más importante es la fiebre. Objetivo caracterizar una serie de casos pediátricos hospitalizados a causa de infección del tracto urinario. Métodos se realizó un estudio descriptivo, de tipo serie de casos, en el Hospital Pediátrico de Camagüey, durante el periodo de enero a marzo de 2023. La muestra quedó conformada por 112 pacientes, una vez aplicados los criterios de selección. Fueron estudiadas las variables: grupo etario y sexo, área de salud, signos y síntomas clínicos, factores de riesgo y gérmenes aislados. El procesamiento de los datos se realizó mediante el paquete estadístico para las ciencias sociales y los resultados se expresaron en valores absolutos y porcentajes. Resultados predominó el grupo etario de menores de un año (31,2 %) y el sexo femenino (68,7 %). El Área de Salud Finlay fue la que más casos aportó (22,3 %), mientras que la fiebre resultó el síntoma preponderante (93,8 %), así como el abandono de la lactancia materna se comportó como el principal factor de riesgo (25,9 %). En el 32,1 % de los casos se aisló el germen Escherichia coli. Conclusiones la infección del tracto urinario es más frecuente en lactantes femeninas, y se constata la fiebre como síntoma principal, además de recogerse como factor de riesgo sustancial el abandono de la lactancia materna.

Foundation urinary tract infection is one of the most common diseases in children and presents with non-specific symptoms, especially in younger children, in which the most important sign is fever. Objective to characterize a series of pediatric cases hospitalized due to urinary tract infection. Methods a descriptive study, of a case series type, was carried out at the Pediatric Hospital of Camagüey, from January to March 2023. The sample was made up of 112 patients, once the selection criteria were applied. The studied variables were: age group and sex, health area, clinical signs and symptoms, risk factors and isolated germs. Data processing was carried out using the statistical package for the social sciences and the results were expressed in absolute values and percentages. Results the age group of children under one year (31.2%) and the female sex (68.7%) predominated. The Finlay Health Area was the one that contributed the most cases (22.3%), while fever was the predominant symptom (93.8%), as well as abandoning breastfeeding as the main risk factor (25.9%). In 32.1% of the cases the Escherichia coli germ was isolated. Conclusions urinary tract infection is more frequent in female infants, and fever is confirmed as the main symptom, in addition to the abandonment of breastfeeding being collected as a substantial risk factor.

Extended-Spectrum Beta-lactamase and Metallo-beta-lactamase Production among Escherichia coli and Klebsiella pneumoniae Strains from Urine of Pregnant Women in Afikpo, Ebonyi State, Nigeria

Aim: The aim of this study was to determine the occurrence of Extended-spectrum beta-lactamase (ESBL) and Metallo-beta-lactamase (MBL) among Escherichia coli and Klebsiella pneumoniae strains from pregnant women attending Mater Misericordia Hospital Afikpo, Ebonyi state, Nigeria. Study Design: This is a laboratory based prospective study carried out on pregnant women suspected of having urinary tract infection and was requested to undergo diagnosis at microbiology laboratory of the hospital. Place and Duration of Study: The study was conducted in the Department of Science Laboratory Technology, Akanu Ibiam Federal Polytechnic, Unwana, Afikpo, Ebonyi State, Nigeria from October, 2022 to January, 2023. Methodology: Clean-catch midstream urine samples were collected from 206 pregnant women suspected of having urinary tract infection and were requested to undergo medical diagnosis at microbiology laboratory of the hospital. The urine samples were processed following standard microbiological procedure. Antimicrobial susceptibility testing was determined using the disc diffusion method, while ESBL phenotypes were determine by the Double-Disc Synergy Test (DDST). Disc potentiation test was performed to check for MBL production. Results: Out of the 206 urine samples processed, 24 (11.7 %) E. coli and 12 (5.8 %) K. pneumoniae were isolated. The antimicrobial susceptibility of the isolates recorded a 100 % resistance with Amoxicillin/Clavulanic acid and Cotrimoxazole. The Gram-negative isolates showed a high sensitivity of 100 % to Netilmicin, Meropenem and Ofloxacin. Overall, 35 (97.2 %) multidrug resistance (MDR) was observed of the bacteria isolates. A total of 9 (37.5 %) E. coli and 4 (33.3 %) K. pneumoniae was found positive for ESBL production whereas, 5 (20.8 %) E. coli and 2 (16.7 %) K. pneumoniae were MBL positive. Conclusion: The level of drug resistance in this study underscores the need for regular surveillance for effective management of urinary tract infection in pregnancy.

Molecular Detection of Plasmid-Mediated Quinolone Resistance Genes (qnrA and aac(6?)-Ib-cr) in Drug Resistant Escherichia coli, Sudan

Background: The quinolone group, a synthetic antimicrobial, is widely used worldwide to treat many diseases, including those caused by Gram-negative bacteria. Escherichia coli and others are among the bacteria that produce quinolone resistance genes (qnr) such as qnrA and aac(6?)-Ib-cr. Objective: The present study aimed to the isolate Escherichia coli from patients attending some Hospitals in Wad Medani city, identification of drug resistance patterns and detection of the frequency of quinolones resistance genes; qnrA and aac(6?)-Ib-cr among isolated strains. Methods: A cross-sectional descriptive, hospital-based study included 119 Escherichia coli strains was conducted. A designed questionnaire used for demographic data collection and the attitude toward antimicrobials usage. Clinical specimens were processed for aerobic bacterial isolation and identification. Antimicrobial sensitivity performed by Kirby Bauer disc diffusion technique according to the CLSI guidelines. Presence of qnrA and aac(6?)-Ib-cr genes was assessed by multiplex PCR. Results: Most strains of Escherichia coli originated from urine 53.8% (64/119) and wounds 42.9% (51/119) specimens. Meropenem had the best effect against tested strains with susceptibility of 85% (101/119). Multiplex PCR assay, using specific primers, demonstrated that 41.2% (49/119) and 37.8% (45/119) of isolated Escherichia coli possessed qnrA and aac(6?)-Ib-cr genes respectively. Conclusion: The high rate of qnrA and aac (6)-Ib-cr genes among Escherichia coli necessitate the usage of molecular tools in detecting the genetic determinants of drug resistance microorganisms in countries such as Sudan.

First molecular characterization of Escherichia coli O157:H7 isolates from clinical samples in Paraguay using whole-genome sequencing Molecular characterization of Escherichia coli O157 isolates from Paraguay / Primera caracterización molecular de aislamientos de Escherichia coli O157:H7 provenientes de muestras clínicas en Paraguay utilizando secuenciación de genoma completo

Abstract Escherichia coli O157:H7 is a foodborne pathogen implicated in numerous outbreaks worldwide that has the ability to cause extra-intestinal complications in humans. The Enteropathogens Division of the Central Public Health Laboratory (CPHL) in Paraguay is working to improve the genomic characterization of Shiga toxin-producing E. coli (STEC) to enhance laboratory-based surveillance and investigation of foodborne disease outbreaks. Whole genome sequencing (WGS) is proposed worldwide to be used in the routine laboratory as a high-resolution tool that allows to have all the results in a single workflow. This study aimed to carry out for the first time, the genomic characterization by WGS of nine STEC O157:H7 strains isolated from human samples in Paraguay. We were able to identify virulence and resistance mechanisms, MLST subtype, and even establish the phylogenetic relationships between isolates. Furthermore, we detected the presence of strains belonging to hypervirulent clade 8 in most of the isolates studied.

Resumen Escherichia coli O157:H7 es un patógeno transmitido por alimentos implicado en numerosos brotes en todo el mundo y es capaz de causar complicaciones extraintestinales en humanos. La sección de «Enteropatógenos¼ del Laboratorio Central de Salud Pública trabaja en mejorar la caracterización genómica de STEC, de modo de potenciar la vigilancia laboratorial y la investigación de brotes de enfermedades transmitidas por alimentos. La secuenciación de genoma completo (WGS, por sus siglas en inglés) se propone a nivel mundial como una herramienta de alta resolución para ser utilizada en el laboratorio de rutina, ya que permite obtener todos los resultados en un único proceso. El objetivo de este trabajo fue llevar a cabo, por primera vez, la caracterización genómica por WGS de nueve cepas STEC O157:H7 aisladas en Paraguay a partir de muestras de origen humano. Pudimos identificar los factores de virulencia, los mecanismos de resistencia, el subtipo MLST, e incluso pudimos establecer la relación filogenética entre los aislamientos. Además, detectamos que la mayoría de las cepas pertenecían al clado hipervirulento 8.

Comprehensive evaluation of abattoirs with no Hazard Analysis Critical Control Point plan in Tucumán,Argentina / Evaluación integral de frigoríficos sin un plan de análisis de peligros y puntos críticos de control en Tucumán, Argentina

Abstract This work focused on the comprehensive study of two provincial transit abattoirs inTucumán, Argentina, with no Hazard Analysis Critical Control Point (HACCP) plan. Visits (n = 20)were conducted between 2016 and 2018 during the operational and post-operational processes.Risk was estimated and the bacteriological analysis of carcass and environmental samples wasperformed. Risk estimation showed the predominance of high risk in both abattoirs. The maindeviations from the HACCP plan were: deficient building conditions, deficient workflow, lack of sectorization of changing rooms and bathrooms, lack of implementation of Standardized Sanitary Operational Procedures, and no food safety training of workers. The counts of indi-cator microorganisms from both abattoirs were not significant. Salmonella spp. was isolated from 7.5% carcass and 7.3% environmental samples. The Salmonella serovars identified were Cerro, Corvallis, Havana and Agona. Shiga toxin (stx) genes were detected in 24.4% carcass and 30.9% environmental samples. The isolates were characterized as Escherichia coli O8:H7/stx1, O116:H49/stx2 and O136:H40/stx2. Based on these results, it would be possible to implement an improvement plan in Tucumán abattoirs together with the local health authorities. Still, the need to work jointly with the sanitary authority in search of a unique sanitary standard for Argentina remains unaddressed.

Resumen Este trabajo se centró en el estudio integral de dos frigoríficos de tránsito provincial en Tucumán, Argentina, carentes de un plan de análisis de peligros y puntos críticos de control (HACCP, por sus siglas en inglés). Las visitas (n = 20) se realizaron entre 2016 y 2018 durante los procesos operativos y posoperativos. Se realizó la estimación del riesgo y el análisis bacteriológico de medias reses y muestras ambientales. La estimación del riesgo demostró un predominio de riesgo alto en ambos frigoríficos. Las principales desviaciones del plan HACCP fueron las deficientes condiciones edilicias, un inadecuado flujo de trabajo, la falta de sectorización de vestuarios y banños, una implementación nula de procedimientos operativos estandarizados de saneamiento y una insuficiente capacitación en seguridad alimentaria de los operarios. Los recuentos de microorganismos indicadores de ambos frigoríficos no presentaron diferencias significativas. Salmonella spp. se aisló del 7,5% de muestras de medias reses y del 7,3% de muestras ambientales. Se identificaron las siguientes serovariedades de Salmonella: Cerro, Corvallis, Havana y Agona. Se detectaron genes de toxina Shiga (sfx) en el 24,4% de las muestras de medias reses y en el 30,9% de las muestras ambientales. Los aislamientos se caracterizaron como Escherichia coli O8:H7/sfx1, O116:H49/sfx2 y O136:H40/sfx2. Teniendo en cuenta estos resultados, sería posible implementar un plan de mejoramiento en frigoríficos de Tucumán conjuntamente con las autoridades locales de salud. Aun así, sigue sin abordarse la necesidad de trabajar en vinculación con las autoridades sanitarias en la búsqueda de una norma integrada única para Argentina.

Actividad bactericida de anticuerpos anti-ABO en colonias aisladas de Escherichia coli

Se ha estudiado la interacción entre antígenos ABO y microorganismos, incluidos los presentes en la microbiota, sobre la posible acción de antígenos y anticuerpos ABO en la susceptibilidad a enfermedades infecciosas. El objetivo de esta investigación fue determinar el título mínimo de la bacteria Escherichia coli capaz de sufrir la acción bactericida in vitro de los anticuerpos humanos anti-ABO. La selección de las muestras de sangre utilizadas se realizó mediante la aplicación de un cuestionario, fenotipado sanguíneo (un voluntario de cada fenotipo ABO) y la titulación de anticuerpos ABO. Se preparó una suspensión bacteriana (inoculo) y se agregó al suero de los voluntarios, seguido de la inoculación en Mueller Hinton Agar, luego de 24 horas, los resultados se leyeron e interpretaron con análisis por duplicado. No hubo diferencia significativa en la Prueba Bactericida entre las pruebas 1 y 2 en los grupos sanguíneos A, B, AB, O y Control Positivo. Hubo una diferencia significativa en el suero humano puro cuando se analizó el Grupo A x Control Positivo; Grupo B x Control Positivo; Grupo AB x Control Positivo y Grupo O x Control Positivo. No hubo diferencia significativa en las otras diluciones. Se concluye que los anticuerpos anti-ABO tienen efecto bactericida cuando existe una alta concentración de bacterias en el ambiente.

The interaction between ABO antigens and microorganisms, including those present in the microbiota, has been studied about the possible action of antigens and ABO antibodies in susceptibility to infectious diseases. This research aimed to determine the minimum titer of the Escherichia coli bacteria capable of undergoing in vitro bactericidal action of human anti-ABO antibodies. The selection of blood samples was performed through a questionnaire, blood phenotyping (one volunteer of each ABO phenotype), and the titration of ABO antibodies. A bacterial suspension (inoculum) was prepared and added to the serum of the volunteers, followed by inoculation in Mueller Hinton Agar. After 24 hours, the results were read and interpreted with duplicate analysis. There was no significant difference in the bactericidal test between tests 1 and 2 in blood groups A, B, AB, O, and Positive Control. There was a significant difference in pure human serum when Group A x Positive Control was analyzed, Group B x Positive Control, Group AB x Positive Control, and Group O x Positive Control. There was no significant difference in the other dilutions. It is concluded that anti-ABO antibodies have a bactericidal effect when there is a high concentration of bacteria in the environment.

Análisis retrospectivo de perfil microbiológico y resistencia antimicrobiana en infección urinaria pediátrica de hospitales públicos de Quito-Ecuador

Objetivo: Determinar el perfil microbiológico y resistencia antimicrobiana en infección urinaria en niños. Materiales y métodos: Estudio descriptivo, transversal, observacional y multicéntrico. Se estudiaron 445 urocultivos procesados y los resultados de antibiogramas en tres hospitales públicos de Quito (Ecuador). En relación con los agentes causales se establecieron frecuencias absolutas y proporciones. En el análisis bivariable entre el antecedente de malformación renal o de la vía urinaria y el riesgo de infección, se aplicó el test Chi2 (p < 0,05) y la RP [IC 95 %; p < 0,05]. Resultados: Se evidenció una resistencia ante aminopenicilinas del 73,5 %; ampicilina más sulbactam 31,8 %; trimetoprim-sulfametoxazol 55,5 %; cefalosporinas de primera y segunda generación hasta 33 %; cefalosporinas de tercera y cuarta generación del 21,3 al 47 %. Ante malformación urinaria y aislamiento de bacterias diferentes a Escherichia coli, se identificó a Klebsiella pneumoniae RP 2,66 [IC 95 %, 1,9-3,6; p < 0,05] y Pseudomonas aeruginosa RP 2,07 [IC 95 %, 1,2-3,5; p < 0,05]. Conclusiones: En nuestro medio, ante el diagnóstico de infección urinaria, no parece adecuado iniciar tratamiento antibiótico con aminopenicilinas, trimetoprim-sulfametoxazol ni cefalosporinas de primera a cuarta generaciones por su elevada resistencia. La presencia de malformación urinaria se asocia a infección por bacterias diferentes de Escherichia coli.

Objective: Determine the microbiological profile and antimicrobial susceptibility in urinary infection in children. Materials and methods: Descriptive, cross-sectional, observational, and multicenter study. 445 urine cultures and the results of antibiograms were studied in three public hospitals in Quito (Ecuador). In relation to the causal agents, absolute frequencies and proportions were established. In the bivariate analysis, Chi-squared test (p < 0.05) and PR [CI 95 %; p < 0.05] were applied between history of kidney or urinary tract malformation and risk of infection. Results: There was evidence of resistance to aminopenicillins of 73.5 %; ampicillin plus sulbactam 31.8 %; trimethoprim-sulfamethoxazole 55.5 %; first and second generation cephalosporins up to 33 %; resistance to third and fourth generation cephalosporins from 21.3 to 47%. In relation to urinary malformation and the isolate of a bacteria different from Escherichia coli, Klebsiella pneumoniae PR 2,66 [CI 95 %, 1.9-3.6; p < 0.05] and Pseudomonas aeruginosa PR 2.07 [CI 95 %, 1.2-3.5; p < 0.05] were identified. Conclusions: In our locality it wouldn't be appropriate to start antibiotic treatment with aminopenicillins, trimethoprim-sulfamethoxazole or first to fourth generation cephalosporins in urinary tract infection due to their resistance. The presence of urinary malformation is associated with infection by bacteria other than Escherichia coli.

Characterization of third generation cephalosporin-resistant Escherichia coli clinical isolates from Ushuaia, Argentina / Caracterización de aislamientos clínicos de Escherichia coli resistente a cefalosporinas de tercera generación de Ushuaia, Argentina

Abstract Escherichia coli is one of the main human pathogens causing different hospital- and community-acquired infections. During the period from January 2013 to March 2015, 1.96% (32/1632) of E. coli isolates recovered at the Hospital Regional de Ushuaia, Tierra del Fuego province, were resistant to third-generation cephalosporins (TGCs). These isolates were resistant to cefotaxime (91%) and/or ceftazidime (28%). No resistance to carbapenems was detected. Twenty-six isolates were positive for blaCTX-M gene, grouped as CTX-M-1/15 (54%); CTX-M-9/14 (25%); CTX-M-2 (17%); and CTX-M-1/15 plus CTX-M-9/14 (4%). Five TGC-resistant strains were positive for blaCMY gene, while one strain harbored TEM-19 ESBL. Twelve isolates were identified as ST131 E. coli hyperepidemic clone, and one as ST69. Genome sequence analysis of seven blaCTX-M-15 E. coli selected isolates confirm the circulation of ST131, ST617 and ST405 international high-risk clones in the city of Ushuaia.

Resumen Escherichia coli es uno de los principales patógenos humanos causantes de diferentes infecciones de inicio hospitalario y comunitario. Se determinó que el 1,96% (32/1.632) de los aislamientos de E. coli recuperados entre enero de 2013 y marzo de 2015 en el Hospital Regional de Ushuaia, provincia de Tierra del Fuego, fueron resistentes a cefalosporinas de tercera generación (CTG). Estos aislamientos fueron resistentes a cefotaxima (91%) y/o a ceftazidima (28%). No se detectó resistencia a los carbapenemes. Veintiséis aislamientos fueron positivos para el gen blaCTX-M, agrupados como CTX-M-1/15 (54%), CTX-M-9/14 (25%), CTX-M-2 (17%) y CTX-M-1/15 más CTX-M-9/14 (4%). Cinco cepas resistentes a CTG dieron positivo para el gen blaCMY, mientras que un aislamiento presentó la BLEE TEM-19. Doce aislamientos se identificaron como clon hiperepidémico E. coli ST131 y uno como ST69. El análisis de las secuencias del genoma de siete aislamientos seleccionados de E. coli blaCTX-M-15 confirmó la circulación de los clones internacionales de alto riesgo ST131, ST617 y ST405 en la ciudad de Ushuaia.

Características clínicas y microbiológicas de la infección de vías urinarias bajas en población ambulatoria / Clinical and Microbiological Characteristics of Lower Urinary Tract Infections in an Outpatient Population

Introducción: El tratamiento de las infecciones del tracto urinario es casi siempre empírico, lo que genera una serie de problemas en la consulta diaria. Objetivo: Caracterizar clínica y microbiológicamente las infecciones de vías urinarias bajas no complicadas en pacientes de una clínica de primer nivel. Métodos: Se realizó un estudio transversal descriptivo. La identificación de las bacterias del cultivo de orina se efectuó por métodos establecidos. La prueba de susceptibilidad a los antimicrobianos se realizó por la técnica Kirby-Bauer. Se utilizó el programa estadístico SPSS versión 26, con la prueba de ji al cuadrado y un análisis multivariado discriminante. Se calculó también razón de momios con el programa Epi-Info. Resultados: Se incluyeron 270 pacientes, con frecuencia de 39,3 por ciento de cultivos positivos, y Escherichia coli como la especie predominante. Se identificaron, además, 31,3 por ciento de bacterias Gram positivas. Se presentó significancia estadística entre la infección urinaria y factores como el sexo, y la infección del tracto urinario previa en las mujeres. Se obtuvo 100 por ciento de cepas resistentes a ampicilina. En general, se obtuvieron porcentajes de resistencia altos en los antimicrobianos probados. Conclusiones: Escherichia coli fue la especie más frecuentemente aislada, sin embargo, existe una serie de microorganismos implicados en enfermedades del tracto genital como Gardnerella vaginalis, que parecen estar involucrados en la etiología de las infecciones del tracto urinario. Se identificaron factores de riesgo como el sexo biológico y las infecciones previas en mujeres. Se obtuvieron porcentajes de resistencia altos en los antimicrobianos probados(AU)

Introduction: The management of urinary tract infections is almost always empirical, which generates a series of problems in the daily consultation. Objective: To characterize, clinically and microbiologically, uncomplicated lower urinary tract infections in patients of a primary level clinic. Methods: A descriptive and cross-sectional study was carried out. Bacterial identification in urine culture was performed by established methods. Antimicrobial susceptibility testing was performed using the Kirby-Bauer technique. The statistical software SPSS (version 26) was used, with the chi squared test and multivariate discriminant analysis. Odds ratios were also calculated with the Epi-Info program. Results: A total of 270 patients were included, with a 39.3percent frequency of positive cultures and Escherichia coli as the predominant species. In addition, 31.3percent of Gram-positive bacteria were identified. There was statistical significance between urinary tract infection and factors such as sex or previous urinary tract infection in women. One result was 100percent of ampicillin-resistant strains. In general, high percentages of resistance were obtained for the tested antimicrobials. Conclusions: Escherichia coli was the most frequently isolated species; however, there is a number of microorganisms implicated in genital tract diseases, such as Gardnerella vaginalis, which appear to be involved in the etiology of urinary tract infections. Risk factors such as biological sex and previous infections in women were identified. High percentages of resistance were obtained for the tested antimicrobials(AU)

Multiple Resistance in Clinical Isolates of Escherichia coli and Plasmid-mediated Quinolone Resistance Genes

Quinolone antibiotics have been commonly used to treat cases of multiple antibiotic resistance. Unfortunately, quinolone antibiotics have so much been resisted by infectious bacterial agents. This study aimed to evaluate the susceptibility of some clinical isolates of E. coli to some commonly used quinolone antibiotics and the determination of the plasmid-encoded quinolone resistance genes. Our results showed the plasmid quinolone-resistance genes in the following prevalence: qnr genes: qnr S (71.4 %); qnr B (15.4 %); qnr S and B (12.1 %); aac (6) lb-cr (4 %); Efflux genes: oqxA (7.7 %); oqxB (25.3 %); qepA (12.1 %); oqxA and oqxB (5.5 %). We conclude that there is a high frequency of Plasmid-mediated quinolone resistance genes in Escherichia coli isolates from clinical samples in South-Eastern Nigeria. These could be responsible for the high incidence of quinolone resistance reported in Enugu. There is a need for whole-genome sequencing to map out all resistance genes.