Draft genome of the Klebsiella pneumoniae 24Kpn33 and complete sequence of its pCOL-1, a plasmid related to the blaKPC-2 acquisition in Pseudomonas aeruginosa.

We report the draft genome of a clinical multi-resistant Klebsiella pneumoniae (24Kpn33) isolate, whose genome (5.7 Mbp) harbored 17 antibiotic resistance genes, including blaKPC-2. Notably, this gene was mobilized within the IncP-6 pCOL-1 plasmid, the first genetic platform related to the acquisition and dissemination of the blaKPC-2 in Pseudomonas aeruginosa.

Differential gut microbiome in spondyloarthritis patients associated to Blastocystis colonization.

The role of Blastocystis in intestinal health is an open controversy, and little is known about the potential effect of this microorganism in autoinflammatory diseases such as spondyloarthritis (SpA). Here, we analyzed the gut microbiome of 36 SpA patients and 13 control individuals and demonstrated that the richness, diversity, and taxonomic composition between these two groups are different. We also showed that colonization by Blastocystis in control individuals increases the richness and diversity of the intestinal microbiome, whereas in SpA patients, it does not seem to have any impact. This may reflect a potential role of Blastocystis in sculpting the gut microbiome architecture in control individuals, whereas in subjects with SpA, the modulation of the microbiome may be governed by disease-dependent factors that cannot be overcome by Blastocystis. Regarding taxonomic characterization, SpA patients colonized by Blastocystis showed significant increases in the phylum Pseudomonadota, class Gammaproteobacteria, family Succinivibrionaceae, and genus Succinivibrio. Simultaneously, there were significant increases in the class Bacilli, order Lactobacillales, families Lactobacillaceae and Clostridiaceae, and genera Lactobacillus and Clostridium in non-colonized SpA patients. On the other hand, PICRUSt analysis in Blastocystis-positive SpA patients showed elevations in pathways that may enhance antioxidant capacities and alleviate intestinal inflammation, while Blastocystis-negative SpA patients showed significant changes in pathways that promote cell division/proliferation and can lead to larger changes in the gut microbiome. Our analyses lead us to believe that these changes in the gut microbiome of SpA patients may trigger protective mechanisms as an initial response to inflammation in an attempt to restore balance in the intestinal environment.

Colonoscopy aspiration lavages for mucosal metataxonomic profiling of spondylarthritis-associated gastrointestinal tract alterations.

The study of the GI-tract microbiota of spondylarthritis (SpA) patients has focused on the analysis of feces samples, that picture mostly the luminal microbiota. The aim of this study was to determine the contribution of mucosal and luminal microbiome to the gut dysbiosis in SpA, using colonoscopy aspiration lavages (CAL), a recent alternative for regional studies of the GI-tract. We analyzed 59 CAL (from sigmoid colon and distal ileum), and 41 feces samples, from 32 SpA patients and 7 healthy individuals, using 16S rRNA gene-targeted metataxonomic profiling. It was found high prevalence of GI-tract manifestations among SpA patients (65.3%). Metataxonomic profiling, confirmed CAL samples from the lower GI tract (colon or ileum) presented a distinctive and undifferentiated bacteriome and separate from that found in feces' samples or in the beginning of the GI tract (oral cavity (OC)). Lower GI-tract samples and feces of SpA patients exhibited similar behavior to the microbiota of IBD group with reduced microbial richness and diversity, comparing to the healthy controls. Interestingly, it was found increase in proinflammatory taxa in SpA patients, such as Enterobacteriaceae family (mostly in the ileum), Succinivibrio spp. and Prevotella stercorea. Conversely, SpA patients presented significant decrease in the SCFA producers Coprococcus catus and Eubacterium biforme. Our data support the value of CAL samples for the regional study of GI-tract and contribute with information of potential "disruptor taxa" involved in the GI-tract associated disorders observed in SpA patients.

Worldwide Dissemination of blaKPC Gene by Novel Mobilization Platforms in Pseudomonas aeruginosa: A Systematic Review.

The dissemination of blaKPC-harboring Pseudomonas aeruginosa (KPC-Pa) is considered a serious public health problem. This study provides an overview of the epidemiology of these isolates to try to elucidate novel mobilization platforms that could contribute to their worldwide spread. A systematic review in PubMed and EMBASE was performed to find articles published up to June 2022. In addition, a search algorithm using NCBI databases was developed to identify sequences that contain possible mobilization platforms. After that, the sequences were filtered and pair-aligned to describe the blaKPC genetic environment. We found 691 KPC-Pa isolates belonging to 41 different sequence types and recovered from 14 countries. Although the blaKPC gene is still mobilized by the transposon Tn4401, the non-Tn4401 elements (NTEKPC) were the most frequent. Our analysis allowed us to identify 25 different NTEKPC, mainly belonging to the NTEKPC-I, and a new type (proposed as IVa) was also observed. This is the first systematic review that consolidates information about the behavior of the blaKPC acquisition in P. aeruginosa and the genetic platforms implied in its successful worldwide spread. Our results show high NTEKPC prevalence in P. aeruginosa and an accelerated dynamic of unrelated clones. All information collected in this review was used to build an interactive online map.

Peptides DLL37-1 and LL37-1, an alternative to inhibit biofilm formation in clinical isolates of Staphylococcus aureus and Staphylococcus epidermidis.

Staphylococcus aureus and Staphylococcus epidermidis have microbial surface components recognizing adhesive matrix molecules (MSCRAMM) adhesion proteins that enhance their biofilm formation ability, as well as virulence factors that influence morbidity and mortality in hospital settings. In this work, four peptides analogous of the peptide LL-37 that were evaluated to inhibit biofilm formation and its action potential on the expression of MSCRAMM proteins in clinical isolates through different tests, such as crystal violet, PCR and qPCR. In total, 96.8% of S. aureus were strong in biofilm formation in contrast to 48.4% of S. epidermidis. sdrG and sdrF genes were present in 100% of S. epidermidis strains and in all isolates. In S. aureus, specific genes that code for MSCRAMM proteins were detected: clfA (89%), clFB, sdrC and fnBA (94%). The peptides did not show hemolytic or cytotoxic activity. In this study, it was evidenced that of the peptides DLL37-1 at a 5 µM concentration was an efficacious antimicrobial agent and depicted greater biofilm inhibition in both bacterial species. Exhibiting a significant inhibition rate in S. aureus, this peptide caused a negative regulation in the expression of the genes clfA and sdrC, showed greater biological activity.

Bacterioma en nódulos mamarios y sus efectos morfológicos sobre la línea celular del cáncer de mama / Bacterioma in Mammary Nodules and Their Morphological Effects on Breast Cancer Cell Line

Introducción: En el cáncer de mama no se ha reportado una bacteria como causante, pero sí la presencia de diferentes especies que se relacionan de forma beneficiosa o perjudicial. Objetivo: Identificar la microbiota presente en nódulos mamarios y sus efectos morfológicos sobre la línea celular MCF-7. Métodos: Estudio exploratorio experimental de una población de 57 mujeres con nódulos mamarios, intervenidas para biopsia por punción en un centro de diagnóstico. De estas, se escogieron 17 muestras mediante muestreo no probabilístico para el análisis metagenómico. Se realizó una infección con células MCF-7 y Staphylococcus saprophyticus a MOI de 1:1, 5:1 y 10:1 (48 horas de exposición). Resultados: De las 57 muestras tomadas, solo en 7 pacientes se obtuvo resultado positivo (12,28 por ciento) y en el resto (50) no hubo crecimiento bacteriano. Por metagenómica se obtuvo la microbiota siguiente: Proteobacteria (47 por ciento), Escherichia (9,4 por ciento) y Yokenella (8,2 por ciento), entre otros. Los controles fueron negativos. Solo dos pacientes resultaron positivas para cáncer, entre ellas la especie común fue S. saprophyticus. En la infección, los cambios morfológicos se evidenciaron desde la MOI 5:1. Conclusión: El bacterioma extraído de los nódulos de una población femenina es en su mayoría flora endógena del órgano mamario(AU)

Introduction: No bacterium has been reported as causative of breast cancer, but the presence of different species that are related in a beneficial or detrimental way. Objective: To identify the microbiota present in breast nodules and its morphological effects on the MCF-7 cell line. Methods: Exploratory, experimental study of a population of 57 women with breast nodules, operated for needle biopsy in a diagnostic center. Of these, 17 samples were chosen by non-probabilistic sampling for metagenomic analysis. Infection was performed with MCF-7 cells and Staphylococcus saprophyticus at MOI of 1:1, 5:1 and 10:1 (48 hours of exposure). Results: Of the 57 samples taken, only 7 yielded positive results (12.28 percent) and the rest (50) had no bacterial growth. The following microbiota was obtained by metagenomics: Proteobacteria (47 percent), Escherichia (9.4 percent) and Yokenella (8.2 percent), among others. Controls were negative. Only two patients tested positive for cancer, and S. saprophyticus was the common species. In the infection, morphological changes were evidenced from MOI 5:1. Conclusion: The bacteriome extracted from the nodules of a female population is mostly endogenous flora of the mammary glands(AU)

Within patient genetic diversity of blaKPC harboring Klebsiella pneumoniae in a Colombian hospital and identification of a new NTEKPC platform.

Resistance to carbapenems in Klebsiella pneumoniae has been mostly related with the worldwide dissemination of KPC, largely due to the pandemic clones belonging to the complex clonal (CC) 258. To unravel blaKPC post-endemic clinical impact, here we describe clinical characteristics of 68 patients from a high complexity hospital, and the molecular and genetic characteristics of their 139 blaKPC-K. pneumoniae (KPC-Kp) isolates. Of the 26 patients that presented relapses or reinfections, 16 had changes in the resistance profiles of the isolates recovered from the recurrent episodes. In respect to the genetic diversity of KPC-Kp isolates, PFGE revealed 45 different clonal complexes (CC). MLST for 12 representative clones showed ST258 was present in the most frequent CC (23.0%), however, remaining 11 representative clones belonged to non-CC258 STs (77.0%). Interestingly, 16 patients presented within-patient genetic diversity of KPC-Kp clones. In one of these, three unrelated KPC-Kp clones (ST258, ST504, and ST846) and a blaKPC-K. variicola isolate (ST182) were identified. For this patient, complete genome sequence of one representative isolate of each clone was determined. In K. pneumoniae isolates blaKPC was mobilized by two Tn3-like unrelated platforms: Tn4401b (ST258) and Tn6454 (ST504 and ST846), a new NTEKPC-IIe transposon for first time characterized also determined in the K. variicola isolate of this study. Genome analysis showed these transposons were harbored in different unrelated but previously reported plasmids and in the chromosome of a K. pneumoniae (for Tn4401b). In conclusion, in the blaKPC post-endemic dissemination in Colombia, different KPC-Kp clones (mostly non-CC258) have emerged due to integration of the single blaKPC gene in new genetic platforms. This work also shows the intra-patient resistant and genetic diversity of KPC-Kp isolates. This circulation dynamic could impact the effectiveness of long-term treatments.

Estimation of the Difference in Colistin Plasma Levels in Critically Ill Patients with Favorable or Unfavorable Clinical Outcomes.

In recent decades, antimicrobial resistance (AMR) has led to an increased use of therapeutic alternatives. Among these options, colistin continues to be an option for the treatment of multi-resistant (MDR) Gram-negative bacterial infections. However, due to its high toxicity (nephrotoxicity and neurotoxicity) and narrow therapeutic window, colistin treatment must be utilized carefully. Colistin-treated patients have been observed to have higher mortality due to inadequate therapeutic levels. The objective of this study was to estimate the difference in colistin plasma levels in critically ill patients, and its relationship to favorable or unfavorable clinical outcomes. This prospective observational study was conducted between September 2017 and June 2020 at the Universidad de La Sabana Clinic, in patients who had been treated with colistimethate sodium (CMS) for at least 72 h until day 7 of drug treatment in the critical care unit of a university hospital. There were no statistically significant differences in colistin levels between groups with favorable or unfavorable clinical outcomes (0.16 SD vs. 0.54 SD p-value = 0.167). There was higher mortality in patients with subtherapeutic levels (18% vs. 0%), and additionally, there was a greater rate of renal failure in the group with higher therapeutic levels (50% vs. 20.7%). Due to the loss of power of the study, we were unable to demonstrate a possible difference between colistin levels related to favorable or unfavorable clinical outcomes at day 7. However, we recommend further studies to evaluate the impact of measuring levels in terms of mortality and security.

Plataformas de secuenciación de nueva generación y proteómica aplicadas a la virología vegetal: ¿Cómo ha avanzado Colombia? / Next generation sequencing and proteomics in plant virology: how is colombia doing?

ABSTRACT Crop production and trade are two of the most economically important activities in Colombia, and viral diseases cause a high negative impact to agricultural sector. Therefore, the detection, diagnosis, control, and management of viral diseases are crucial. Currently, Next-Generation Sequencing (NGS) and 'Omic' technologies constitute a right-hand tool for the discovery of novel viruses and for studying virus-plant interactions. This knowledge allows the development of new viral diagnostic methods and the discovery of key components of infectious processes, which could be used to generate plants resistant to viral infections. Globally, crop sciences are advancing in this direction. In this review, advancements in 'omic' technologies and their different applications in plant virology in Colombia are discussed. In addition, bioinformatics pipelines and resources for omics data analyses are presented. Due to their decreasing prices, NGS technologies are becoming an affordable and promising means to explore many phytopathologies affecting a wide variety of Colombian crops so as to improve their trade potential.

RESUMEN La producción y el comercio de cultivos es una de las actividades económicas más importantes para el país. Las enfermedades causadas por virus ocasionan graves pérdidas económicas en el sector, por lo tanto, la detección, diagnóstico y diseño de estrategias para su control y manejo es crucial. Las tecnologías de secuenciación masiva (NGS por sus siglas en ingles) y las ciencias Ómicas constituyen hoy, una herramienta para el descubrimiento de nuevos virus y para el estudio de la interacción entre los virus y su hospedero vegetal. Este conocimiento no solo permite el desarrollo de nuevos métodos de diagnóstico, sino también permite el descubrimiento de componentes claves en la infección, los cuales podrían usarse para obtener plantas resistentes a los virus. En el mundo, el manejo de cultivos se está trabajando con ese enfoque. Por lo tanto, en esta revisión se presentan las diferentes aplicaciones de las tecnologías ómicas en la virología de plantas y el avance que ha alcanzado Colombia. Adicionalmente, se muestran los diferentes recursos y programas usados para el análisis bioinformático de datos ómicos. Debido a su costo cada vez más reducido, las tecnologías NGS son una excelente oportunidad para explorar fitopatologías en una gran diversidad de productos agrícolas y para mejorar su potencial comercial.

First Report and Comparative Genomics Analysis of a blaOXA-244-Harboring Escherichia coli Isolate Recovered in the American Continent.

The carbapenemase OXA-244 is a derivate of OXA-48, and its detection is very difficult in laboratories. Here, we report the identification and genomic analysis of an Escherichia coli isolate (28Eco12) harboring the blaOXA-244 gene identified in Colombia, South America. The 28Eco12 isolate was identified during a retrospective study, and it was recovered from a patient treated in Colombia. The complete nucleotide sequence was established using the PacBio platform. A comparative genomics analysis with other blaOXA-244-harboring Escherichia coli strains was performed. The 28Eco12 isolate belonged to sequence type (ST) 38, and its genome was composed of two molecules, a chromosome of 5,343,367 bp and a plasmid of 92,027 bp, which belonged to the incompatibility group IncY and did not harbor resistance genes. The blaOXA-244 gene was chromosomally encoded and mobilized by an ISR1-related Tn6237 composite transposon. Notably, this transposon was inserted and located within a new genomic island. To our knowledge, this is the first report of a blaOXA-244-harboring Escherichia coli isolate in America. Our results suggest that the introduction of the OXA-244-producing E. coli isolate was through clonal expansion of the ST38 pandemic clone. Other isolates producing OXA-244 could be circulating silently in America.

Pseudomonas aeruginosa Coharboring BlaKPC-2 and BlaVIM-2 Carbapenemase Genes.

Pseudomonas aeruginosa, a bacterium commonly isolated from hospital settings, exhibits intrinsic resistance to a number of antibiotics and can acquire resistance during antibiotic therapy. Resistance towards carbapenems is increasing due to its overuse in the treatment of infections caused by extended-spectrum ß-lactamase (ESBL) producing organisms. Nonetheless, carbapenems are essential for the treatment of high-risk infections and are one of the remaining weapons in the fight against "extreme drug resistance" of Gram-negative/positive bacilli. Herein, we describe a case report of infections caused by P. aeruginosa strains that carry blaVIM-2 and blaKPC-2 carbapenemase genes simultaneously, identified in five patients who were admitted to a high complexity health institution in Colombia. Molecular characterization included PCR screening for blaKPC, blaGES, blaOXA-48, blaIMP, blaNDM, and blaVIM carbapenemase and other resistance genes as well as analysis of the genetic relationships by genome macro-restriction and Pulsed-Field Gel Electrophoresis (PFGE) separation. In conclusion, these infections represent a major challenge to public health due to the risk of the infection spreading compounded by the fact that limited treatment options are available, thereby increasing the risk of increased morbidity and mortality.

Bacteremia by colistin-resistant Acinetobacter baumannii isolate: a case report.

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii infections are a major public health problem worldwide, requiring the use of "old" antibiotics such as polymyxin B and E (colistin). However, there is concern regarding the emergence of isolates resistant to these antibiotics. CASE PRESENTATION: We report a case of a 64-year-old mestizo man hospitalized in an intensive care unit of a health institution in Colombia with identification and clinical and molecular typing of a colistin- and carbapenem-resistant A. baumannii isolate with mechanisms of resistance to colistin not previously reported, causing bacteremia. CONCLUSIONS: We have identified a strain of A. baumannii with mechanisms of resistance to colistin not previously reported in a patient with bacteremia who required treatment with multiple antibiotic schemes and had an adequate response.

Genome plasticity favours double chromosomal Tn4401b-blaKPC-2 transposon insertion in the Pseudomonas aeruginosa ST235 clone.

BACKGROUND: Pseudomonas aeruginosa Sequence Type 235 is a clone that possesses an extraordinary ability to acquire mobile genetic elements and has been associated with the spread of resistance genes, including genes that encode for carbapenemases. Here, we aim to characterize the genetic platforms involved in resistance dissemination in blaKPC-2-positive P. aeruginosa ST235 in Colombia. RESULTS: In a prospective surveillance study of infections in adult patients attended in five ICUs in five distant cities in Colombia, 58 isolates of P. aeruginosa were recovered, of which, 27 (46.6%) were resistant to carbapenems. The molecular analysis showed that 6 (22.2%) and 4 (14.8%) isolates harboured the blaVIM and blaKPC-2 genes, respectively. The four blaKPC-2-positive isolates showed a similar PFGE pulsotype and belonged to ST235. Complete genome sequencing of a representative ST235 isolate shows a unique chromosomal contig of 7097.241 bp with eight different resistance genes identified and five transposons: a Tn6162-like with ant(2″)-Ia, two Tn402-like with ant(3″)-Ia and blaOXA-2 and two Tn4401b with blaKPC-2. All transposons were inserted into the genomic islands. Interestingly, the two Tn4401b copies harbouring blaKPC-2 were adjacently inserted into a new genomic island (PAGI-17) with traces of a replicative transposition process. This double insertion was probably driven by several structural changes within the chromosomal region containing PAGI-17 in the ST235 background. CONCLUSION: This is the first report of a double Tn4401b chromosomal insertion in P. aeruginosa, just within a new genomic island (PAGI-17). This finding indicates once again the great genomic plasticity of this microorganism.

First Detection of the CTXM-15 Producing Escherichia coli O25-ST131 Pandemic Clone in Ecuador.

Our aim was identify of the pandemic B2-ST131 Escherichia coli clone by to the Institute Pasteur and Achtman scheme, and investigate the resistance profile phenotypic-genotypic, with identification of class 1 integron. Of thirty-five ESBL-producing isolates recovered of patients with diagnosis of urinary tract infections (UTI), six E. coli strains serotype O25 were identified with resistance antimicrobial to several groups of antibiotics such as broad-spectrum cephalosporins, fluoroquinolones and aminoglycosides, harboring blaSHV, blaCTX-M genes in all isolates and blaTEM in two isolates. Sequencing of blaCTX-M revealed CTX-M-15 in all strains. The PMQR aac(6´)-Ib-cr and qnrB19 genes were presented in five and four isolates respectively, AMEs genes aac(6´)-Ib and aac(3)-IIa were presented in strain amikacin-gentamicin-resistant. Sequencing of the variable regions of the class 1 integron revealed dfrA and aadA genes cassette. The analysis of multilocus sequence typing (MLST) confirms the presence of the pandemic B2-ST131 E. coli clone by Achtman scheme in all ST43 isolates obtained by of the Institute Pasteur scheme. The results presented herein, reveal the presence of B2-ST131 E. coli clone in Ecuador, disseminated in hospitals and community settings.

Anti-microbial sensitivity of enterobacteria identified in community-acquired urinary tract infection in pregnant women in 9 Colombian hospitals / Susceptibilidad antimicrobiana de enterobacterias identificadas en infección urinaria adquirida en la comunidad, en gestantes en nueve hospitales de Colombia

ABSTRACT Objective: To identify sensitivity profiles of the main anti-microbial agents used in the management of community-acquired urinary tract infection in pregnant women, and to make the molecular characterisation in order to confirm the existence of bacterial resistance in this population group. Materials and methods: Descriptive crosssectional study that included pregnant women with community-acquired urinary tract infection requiring admission to hospital. They were part of a study conducted in the general population. The microbiological results of the urine cultures were analysed. Isolates of Escherichia coli, Klebsiella spp. And Proteus mirabilis were identified over a period of 12 months in 9 Colombian hospitals, and their sensitivity profiles were determined using microdilution broth and gradient diffusion tests, and the presence of extended spectrum beta-lactamases was characterised using microbiological and molecular methods.The sociodemographic and clinical characteristics of these patients are presented. Results: Overall, 74 isolates were collected (64 E. coli, 7 Klebsiella spp. and 3 P. mirabilis isolates) in 73 patients. Prior use of antibiotics was documented in 58% of the patients. Resistance to ampicillin/sulbactam, cefazolin and ceftriaxone was 15.6%, 17.2% and 4.7%, respectively. There was extended spectrum beta-lactamase expression in three of the isolates, 2 of E. coli and 1 of Klebsiella spp. (3.1% E. coli and 14.3% Klebsiella spp.) One E. coli isolate expressed enzymes of the AmpC type. Conclusion: The presence of resistant strains to antibiotics used as first-line empirical treatment and to third-generation cephalosporins was confirmed in enterobacteria responsible for community-acquired urinary tract infection in pregnant women, produced by type CTX M-15 and AmpC extended spectrum betalactamase enzymes.

RESUMEN Objetivo: determinar los perfiles de susceptibilidad a los principales agentes antimicrobianos utilizados en el manejo de infección de vías urinarias adquirida por gestantes en la comunidad, y caracterizarlos molecularmente para confirmar la existencia de resistencia bacteriana en este grupo poblacional. Materiales y métodos: Estudio de corte transversal, descriptivo, en el que se incluyeron gestantes con infección urinaria adquirida en la comunidad que requirieron hospitalización. Estas hacían parte de un estudio realizado en población general. Se analizaron los resultados microbiológicos de los urocultivos. Se identificaron los aislamientos de Escherichia coli, Klebsiella spp. y Proteus mirabilis durante 12 meses en 9 hospitales de Colombia, y se determinó su perfil de susceptibilidad por microdilución en caldo y pruebas de difusión por gradiente; se caracterizó la presencia de betalactamasas de espectro extendido, con métodos microbiológicos y moleculares. Se presentan las características sociodemográficas y clínicas de estas pacientes. Resultados: se recogieron 74 aislamientos (64 de E. coli, 7 de Klebsiella spp. y 3 de P. mirabilis) en 73 pacientes. En 58 % de las pacientes se reportó uso previo de antibióticos. La resistencia a ampicilina/sulbactam, cefazolina y ceftriaxona fue de 15,6, 17,2 y 4,7 %, respectivamente. Tres aislamientos, dos de E. coli y uno de Klebsiella spp., expresaron betalactamasas de espectro extendido (3,1 % en E. coli y 14,3 % Klebsiella spp.). Un aislamiento de E. coli expresó enzimas tipo AmpC. Conclusión: se confirmó la presencia de cepas resistentes a antibióticos utilizados de primera línea de manera empírica, y a cefalosporinas de tercera generación en enterobacterias responsables de infección del tracto urinario adquirida en la comunidad en embarazadas, producida por enzimas de tipo betalactamasas de espectro extendido tipo CTX M-15 y AmpC.

[Antimicrobial susceptibility profile in urinary pathogens causing community-acquired infections in diabetic patients in Colombia].

INTRODUCTION: Urinary tract infection is the most common pathology in diabetic patients, and an important determinant of morbidity and mortality among them. The increasing resistance of uropathogens acquired in the community to commonly used antibiotics is alarming. OBJECTIVE: To identify the profile of antibiotic susceptibility of uropathogens responsible for communityacquired infections among diabetic patients in hospitals in Colombia. MATERIALS AND METHODS: We conducted a descriptive study in a subgroup of diabetic patients in the framework of a larger study in adults with urinary tract infection acquired in the community. Over one year, we collected Escherichia coli, Klebsiella spp. and Proteus mirabilis isolates from nine hospitals in Colombia. Their susceptibility profile was determined using microbiological and molecular methods to establish the presence of extended-spectrum AmpC betalactamases and KPC carbapenemases. RESULTS: We collected 68 isolates (58 E. coli, nine Klebsiella spp. and one Proteus mirabilis). Four (6.9%) of the E. coli isolates expressed extended spectrum betalactamases, two (3.4%) of them belonged to the phylogenetic group B2 and to ST131 clone and expressed the TEM-1 and CTM-X-15 betalactamases. The AmpC phenotype was found in four (6.9%) of the E. coli isolates, three of which produced TEM-1 and CMY-2 betalactamases. One K. pneumoniae isolate expressed the KPC-3 carbapenemase. CONCLUSION: The presence of extended spectrum betalactamases and carbapenemases in uropathogens responsible for community-acquired infection was confirmed in diabetic patients.

Genomic Epidemiology of NDM-1-Encoding Plasmids in Latin American Clinical Isolates Reveals Insights into the Evolution of Multidrug Resistance.

Bacteria that produce the broad-spectrum Carbapenem antibiotic New Delhi Metallo-ß-lactamase (NDM) place a burden on health care systems worldwide, due to the limited treatment options for infections caused by them and the rapid global spread of this antibiotic resistance mechanism. Although it is believed that the associated resistance gene blaNDM-1 originated in Acinetobacter spp., the role of Enterobacteriaceae in its dissemination remains unclear. In this study, we used whole genome sequencing to investigate the dissemination dynamics of blaNDM-1-positive plasmids in a set of 21 clinical NDM-1-positive isolates from Colombia and Mexico (Providencia rettgeri, Klebsiella pneumoniae, and Acinetobacter baumannii) as well as six representative NDM-1-positive Escherichia coli transconjugants. Additionally, the plasmids from three representative P. rettgeri isolates were sequenced by PacBio sequencing and finished. Our results demonstrate the presence of previously reported plasmids from K. pneumoniae and A. baumannii in different genetic backgrounds and geographically distant locations in Colombia. Three new previously unclassified plasmids were also identified in P. rettgeri from Colombia and Mexico, plus an interesting genetic link between NDM-1-positive P. rettgeri from distant geographic locations (Canada, Mexico, Colombia, and Israel) without any reported epidemiological links was discovered. Finally, we detected a relationship between plasmids present in P. rettgeri and plasmids from A. baumannii and K. pneumoniae. Overall, our findings suggest a Russian doll model for the dissemination of blaNDM-1 in Latin America, with P. rettgeri playing a central role in this process, and reveal new insights into the evolution and dissemination of plasmids carrying such antibiotic resistance genes.

Perfil de sensibilidad antimicrobiana de microorganismos causantes de infecciones urinarias adquiridas en la comunidad en pacientes con diabetes mellitus en Colombia / Antimicrobial susceptibility profile in urinary pathogens causing community-acquired infections in diabetic patients in Colombia

Resumen Introducción. La infección de las vías urinarias es la más frecuente en pacientes diabéticos, y es un factor determinante de la morbilidad y la mortalidad en este grupo de pacientes. El aumento de la resistencia de los microorganismos adquiridos en la comunidad a los antibióticos comúnmente utilizados para combatirla es alarmante. Objetivo. Determinar el perfil de sensibilidad a los antibióticos de los microorganismos responsables de infecciones urinarias adquiridas en la comunidad en pacientes diabéticos atendidos en algunos hospitales de Colombia. Materiales y métodos. Se hizo un estudio descriptivo de un subgrupo de pacientes diabéticos en el marco de una investigación en adultos con infección de origen comunitario de las vías urinarias. Durante un año, se recolectaron aislamientos de Escherichia coli, Klebsiella spp. y Proteus mirabilis en nueve hospitales de Colombia y se determinó su perfil de sensibilidad mediante métodos microbiológicos y moleculares, para establecer la presencia de betalactamasas de espectro extendido del tipo AmpC y de carbapenemasas del tipo KPC. Resultados. Se recolectaron 68 aislamientos (58 de E. coli, nueve de Klebsiella spp. y uno de P. mirabilis). Cuatro (6,9 %) de los aislamientos de E. coli expresaron dichas betalactamasas, en dos (3,4 %) de ellos, pertenecientes al grupo filogenético B2 y al clon ST131, se detectaron las betalactamasas TEM-1 y CTM-X-15. En otros cuatro (6,9 %) aislamientos de E. coli se encontró el fenotipo AmpC, y en tres de ellos se produjeron las betalactamasas TEM-1 y CMY-2. Un aislamiento de K. pneumoniae expresó la carbapenemasa KPC-3. Conclusión. Se confirmó la presencia de cepas productoras de betalactamasas de espectro extendido y carbapenemasas en microorganismos responsables de infección urinaria adquirida en la comunidad en pacientes diabéticos.

Abstract Introduction: Urinary tract infection is the most common pathology in diabetic patients, and an important determinant of morbidity and mortality among them. The increasing resistance of uropathogens acquired in the community to commonly used antibiotics is alarming. Objective: To identify the profile of antibiotic susceptibility of uropathogens responsible for community-acquired infections among diabetic patients in hospitals in Colombia. Materials and methods: We conducted a descriptive study in a subgroup of diabetic patients in the framework of a larger study in adults with urinary tract infection acquired in the community. Over one year, we collected Escherichia coli, Klebsiella spp. and Proteus mirabilis isolates from nine hospitals in Colombia. Their susceptibility profile was determined using microbiological and molecular methods to establish the presence of extended-spectrum AmpC betalactamases and KPC carbapenemases. Results: We collected 68 isolates (58 E. coli, nineKlebsiella spp. and oneProteus mirabilis). Four (6.9%) of the E. coli isolates expressed extended spectrum betalactamases,two (3.4%) of thembelonged to the phylogenetic group B2 andto ST131 clone and expressed the TEM-1 and CTM-X-15 betalactamases. The AmpC phenotype was found in four(6.9%) of the E. coli isolates, three of which producedTEM-1 and CMY-2 betalactamases. One K. pneumoniaeisolate expressed the KPC-3 carbapenemase. Conclusion: The presence of extended spectrum betalactamases and carbapenemases in uropathogens responsible for community-acquired infection was confirmed in diabetic patients.

Participation of the arcRACME protein in self-activation of the arc operon located in the arginine catabolism mobile element in pandemic clone USA300

ABSTRACT Staphylococcus aureus pandemic clone USA300 has, in addition to its constitutive arginine catabolism (arc) gene cluster, an arginine catabolism mobile element (ACME) carrying another such cluster, which gives this clone advantages in colonisation and infection. Gene arcR, which encodes an oxygen-sensitive transcriptional regulator, is inside ACME and downstream of the constitutive arc gene cluster, and this situation may have an impact on its activation. Different relative expression behaviours are proven here for arcRACME and the arcACME operon compared to the constitutive ones. We also show that the artificially expressed recombinant ArcRACME protein binds to the promoter region of the arcACME operon; this mechanism can be related to a positive feedback model, which may be responsible for increased anaerobic survival of the USA300 clone during infection-related processes.

Participation of the arcRACME protein in self-activation of the arc operon located in the arginine catabolism mobile element in pandemic clone USA300.

Staphylococcus aureus pandemic clone USA300 has, in addition to its constitutive arginine catabolism (arc) gene cluster, an arginine catabolism mobile element (ACME) carrying another such cluster, which gives this clone advantages in colonisation and infection. Gene arcR, which encodes an oxygen-sensitive transcriptional regulator, is inside ACME and downstream of the constitutive arc gene cluster, and this situation may have an impact on its activation. Different relative expression behaviours are proven here for arcRACME and the arcACME operon compared to the constitutive ones. We also show that the artificially expressed recombinant ArcRACME protein binds to the promoter region of the arcACME operon; this mechanism can be related to a positive feedback model, which may be responsible for increased anaerobic survival of the USA300 clone during infection-related processes.