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Early detection of disseminating vancomycin-resistant Enterococcus faecium (VREfm) in ICU wards is crucial for outbreak identification and the implementation of prompt infection control measures. Genotypic methods like pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS) are costly and time-consuming, hindering rapid response due to batch dependency. Fourier-transform infrared spectroscopy (FT-IR) offers the potential for real-time outbreak detection and reliable strain typing. We utilized FT-IR to identify clonal VREfm dissemination and compared its performance to PFGE and WGS. Between February through October 2023, an unusually high number of VREfm were recovered at a tertiary hospital in Barcelona. Isolates were examined for antimicrobial susceptibility, carriage of vanA/vanB genes and clonality was also studied using FT-IR, PFGE, and WGS. Routine FT-IR inspections revealed recurring VREfm clustering during the outbreak's initial weeks. In total, 104 isolates were recovered from 75 patients and from multiple wards. However, only one isolate was recovered from an environmental sample, suggesting the absence of environmental reservoirs. An ST80 vancomycin-resistant (vanA) E. faecium strain was the main strain responsible for the outbreak, although a few additional VREfm strains were also identified, all belonging to CC17. PFGE and cgMLST (WGS) yielded identical clustering results to FT-IR, and WGS confirmed vanA/vanB gene carriage in all VREfm isolates. Infection control measures led to a rapid decline in VREfm isolates, with no isolates detected in November. FT-IR spectroscopy offers rapid turnaround times, sensitivity, and reproducibility, comparable to standard typing methods. It proved as an effective tool for monitoring VREfm dissemination and early outbreak detection.
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Infecção Hospitalar , Eletroforese em Gel de Campo Pulsado , Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Enterococos Resistentes à Vancomicina , Sequenciamento Completo do Genoma , Humanos , Enterococcus faecium/genética , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/isolamento & purificação , Enterococcus faecium/classificação , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/isolamento & purificação , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/classificação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Infecção Hospitalar/microbiologia , Infecção Hospitalar/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Sequenciamento Completo do Genoma/métodos , Surtos de Doenças , Proteínas de Bactérias/genética , Testes de Sensibilidade Microbiana , Espanha/epidemiologia , Carbono-Oxigênio Ligases/genética , Antibacterianos/farmacologiaRESUMO
Polymers can serve as an effective matrix to stabilize gold nanoparticles. These materials offer a continuous light-activated supply of subnanoclusters, which are composed of a few atoms. We report an efficient approach to enhance the catalytic activity of gold subnanoclusters by in situ feeding of these species through the generation of hot carriers via 5d-6s6p interband transitions on PEG-stabilized Au nanoparticles.
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OBJECTIVE: To determine whether small, incidentally detected testicular lesions can be safely followed up, by assessing growth rate and volume threshold for benign vs. malignant lesions. METHODS: This retrospective observational study includes a consecutive series of 130 testicular incidentalomas < 1 cm and with negative tumour markers identified from October 2001 to November 2022, which were initially followed up with ultrasound. A total of 39 cases proceeded to surgery during the study period, either due to lesion growth (n = 28) or patient preference/recommendation by the referring urologist (n = 11). For the lesions that were growing, specific growth rate (SGR) and doubling time (DT) were calculated assuming an exponential growth pattern. In addition, the velocity of increase of the average diameter (∆Dav) and of the maximum diameter (∆Dmax) were calculated. RESULTS: Of the 130 nodules that were initially followed up, six disappeared, eight were reduced in size, eighty-eight were stable, and twenty-eight increased in size. For operated nodules all 18 malignant tumours, 8/9 benign tumours, and 2/12 surgically proved non-neoplastic lesions were growing. The best cut-off values of the growth indicators to differentiate between malignant and non-malignant histology were 3.47 × 10-3%volume/day, ≤ 179 days, > 10 × 10-3 mm/day, and > 5 × 10-3 mm/day for SGR, DT, ∆Dmax, ∆Dav, respectively. CONCLUSIONS: Malignant and non-malignant small incidentalomas can be effectively differentiated based on growing parameters, even though overlap exists. An increase of the maximum diameter of about 1 mm and 2 mm in three months and in six months, respectively, suggests malignancy. CLINICAL RELEVANCE STATEMENT: Growing parameters allow an educated assessment of benign and malignant small testicular incidentalomas. Non-aggressive management is justified and safe when follow-up includes self-examination and tumour marker assessment to reduce the risk of interval tumour growth. KEY POINTS: Small, non-palpable and asymptomatic testicular nodules < 1 cm are unexpectedly discovered during scrotal ultrasound. Growth indicators estimate the potential malignancy, even though overlap with non-malignant lesions exists. Non-growing incidentalomas can be safely followed up.
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Although contrast-enhanced ultrasound (CEUS) is a widespread and easily manageable technique, image interpretation errors can occur due to the operator's inexperience and/or lack of knowledge of the frequent pitfalls, which may cause uncertain diagnosis and misdiagnosis. Indeed, knowledge of the basic physical and technical principles of ultrasound is needed both to understand sonographic image findings and to evaluate the potential and limits of the method. Like the B-mode ultrasound, the quality of the CEUS examination is also subject not only to the adequate manual skill of the operator but also to his/her deep knowledge of the technique which improves the quality of the image helping avoid misleading artifacts. In this review, the main parameters influencing a CEUS examination will be described by taking into account the most common errors and pitfalls and their possible solutions.
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Artefatos , Meios de Contraste , Humanos , Masculino , Feminino , Ultrassonografia/métodos , Erros de DiagnósticoRESUMO
BACKGROUND: Immune checkpoint inhibitors have revolutionized the therapeutic approach to several solid tumors, becoming the standard of care for cancer treatment in different disease settings. Despite the fact that these agents are better tolerated than conventional chemotherapy, their use is associated with a specific toxicity profile, so-called immune-related adverse events (irAEs), that can involve several organs. Endocrine irAEs are among the most frequent toxicities (around 10 to 16%) and include hypophysitis, thyroid disorders, adrenalitis, and diabetes mellitus. Some of them may be life-threatening if not promptly recognized (such as diabetic ketoacidosis and acute adrenal crisis). CASE PRESENTATION: A 55-year-old woman with a personal history of euthyroid Hashimoto's thyroiditis was diagnosed with a metastatic melanoma, BRAF wild type. Under treatment with anti-PD-1 pembrolizumab, she developed thyrotoxicosis followed by hypothyroidism due to destructive thyroiditis and concurrent primary adrenal insufficiency due to adrenalitis. CONCLUSIONS: The simultaneous occurrence of adrenal and thyroid autoimmune diseases, resembling autoimmune polyendocrine syndrome type 2, may occur as a rare but serious side effect of ICI treatment. It often presents with abrupt onset and rapid evolution towards polyglandular insufficiency. Physicians should be aware of the potential association of two or more endocrine disorders and careful monitoring of endocrine function is needed during ICI therapy.
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The role of multiparametric MRI (mpMRI) in prostate cancer setting is increasingly consolidated and, as a result, its usage in clinical practice is in exponential growth. However, beyond the prostate gland, several key structures are included in the field of view of mpMRI scans. Consequently, various extra-prostatic incidental findings (IFs) belonging to different anatomical systems can be accidentally recognized. Therefore, it is mandatory for a radiologist to be familiar with the wide range of pathologies potentially encountered, to guide management and avoid patient anxiety and costs due to additional work-up prompted by clinically insignificant extra-prostatic findings. With this pictorial review, we aim to illustrate a wide range of IFs that can be detected when performing mpMRI of the prostate, focusing on their imaging characteristics, differential diagnosis, and clinical relevance. Additionally, we propose the CheckDEEP, the Checklist for DEtection of ExtraProstatic findings, to be used for a thorough evaluation of target areas within each anatomical system.
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Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Masculino , Humanos , Próstata/diagnóstico por imagem , Achados Incidentais , Neoplasias da Próstata/diagnóstico por imagem , Lista de ChecagemRESUMO
CONTEXT: Unlike palpable lumps, a large number of nonpalpable testicular lesions found incidentally at ultrasound in asymptomatic postpuberal males are either benign tumours or non-neoplastic lesions. The prevalence of malignancy, however, is appraised based on small case series. Dedicated studies report a large number of patients, and systematic review articles are lacking. OBJECTIVE: This systematic review is aimed to assess, from the analysis of the pooled data of the available literature, the incidence of benign tumours, malignant tumours, and non-neoplastic lesions, and to identify predictive characteristics for malignancy. EVIDENCE ACQUISITION: A systematic review of PubMed, Scopus, Google Scholar, Turning Research Into Practice (TRIP) database, and the Cochrane Library was conducted on January 6, 2022, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Studies were retrieved reporting on adult asymptomatic men, with single, incidentally identified small testicular lesions, either fertile or infertile, with negative tumour markers and without specific risk factors for malignancy. Lesions ≤20 mm were considered small. Seventy-four studies were selected for inclusion in this analysis. Twenty-six additional publications have been retrieved by the bibliography quoted in the selected articles. EVIDENCE SYNTHESIS: Pooled data of 1348 lesions in 1348 patients were collected. Of these lesions, 408 could be retrieved individually, 44.6% were benign, 27.2% were malignant, and 20.8% were non-neoplastic. Virtually all lesions <3 mm and 86.6% of lesions <5 mm were benign. Lesions >10 mm have a 38.14% probability of being benign. Hyperechoic lesions are likely benign. Fertility status does not affect the risk of malignancy. CONCLUSIONS: Very small (<3 mm) and small (<5 mm) incidentally detected testicular lesions in asymptomatic postpuberal men with normal tumour markers could be frequently benign. More prospective studies are needed to better support this finding. Management strategies should be developed for these patients to reduce overtreatment. PATIENT SUMMARY: Small testicular lesions are incidentally founded at ultrasound. It is not easy to distinguish a benign lesion from a malignant one. Results of this study are reporting a higher incidence of benign lesions with a diameter of <5 mm. More studies are needed to better understand the biology and the management strategy for small testicular lesions.
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Infertilidade , Neoplasias Testiculares , Masculino , Humanos , Adulto , Neoplasias Testiculares/diagnóstico por imagem , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/patologia , Ultrassonografia , Estudos ProspectivosRESUMO
Some transcription factors bind DNA motifs containing direct or inverted sequence repeats. Preference for each of these DNA topologies is dictated by structural constraints. Most prokaryotic regulators form symmetric oligomers, which require operators with a dyad structure. Binding to direct repeats requires breaking the internal symmetry, a property restricted to a few regulators, most of them from the AraC family. The KorA family of transcriptional repressors, involved in plasmid propagation and stability, includes members that form symmetric dimers and recognize inverted repeats. Our structural analyses show that ArdK, a member of this family, can form a symmetric dimer similar to that observed for KorA, yet it binds direct sequence repeats as a non-symmetric dimer. This is possible by the 180° rotation of one of the helix-turn-helix domains. We then probed and confirmed that ArdK shows affinity for an inverted repeat, which, surprisingly, is also recognized by a non-symmetrical dimer. Our results indicate that structural flexibility at different positions in the dimerization interface constrains transcription factors to bind DNA sequences with one of these two alternative DNA topologies.
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DNA , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Sequência de Bases , Sequência de Aminoácidos , Sequências Hélice-Volta-Hélice , DNA/química , Inversão de Sequência , Sítios de LigaçãoRESUMO
Low-copy-number plasmids require sophisticated genetic devices to achieve efficient segregation of plasmid copies during cell division. Plasmid R388 uses a unique segregation mechanism, based on StbA, a small multifunctional protein. StbA is the key protein in a segregation system not involving a plasmid-encoded NTPase partner, it regulates the expression of several plasmid operons, and it is the main regulator of plasmid conjugation. The mechanisms by which StbA, together with the centromere-like sequence stbS, achieves segregation, is largely uncharacterized. To better understand the molecular basis of R388 segregation, we determined the crystal structure of the conserved N-terminal domain of StbA to 1.9 Å resolution. It folds into an HTH DNA-binding domain, structurally related to that of the PadR subfamily II of transcriptional regulators. StbA is organized in two domains. Its N-terminal domain carries the specific stbS DNA binding activity. A truncated version of StbA, deleted of its C-terminal domain, displays only partial activities in vivo, indicating that the non-conserved C-terminal domain is required for efficient segregation and subcellular plasmid positioning. The structure of StbA DNA-binding domain also provides some insight into how StbA monomers cooperate to repress transcription by binding to the stbDR and to form the segregation complex with stbS.
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Proteínas de Bactérias , Segregação de Cromossomos , Nucleosídeo-Trifosfatase , Plasmídeos , Proteínas de Bactérias/química , DNA/química , DNA/metabolismo , Nucleosídeo-Trifosfatase/química , Nucleosídeo-Trifosfatase/metabolismo , Óperon , Plasmídeos/genética , Domínios ProteicosRESUMO
Background: Ureteropelvic junction obstruction (UPJO) is one of the most frequent causes of congenital hydronephrosis. It is essential to distinguish UPJO which needs surgical treatment. fMRU combines high quality morphological details of the kidney and excretory pathways with functional data. Objective: This study aims to introduce a new radiological score based on fMRU findings to be able to differentiate surgical from non-surgical kidneys. Materials and Methods: We retrospectively selected patients with hydronephrosis due to UPJO who underwent fMRU (January 2009-June 2018). A multidisciplinary team identified a list of fMRU morpho-functional predictive variables to be included in the analysis. To evaluate the role of different independent variables in predicting the outcome, a multivariable logistic regression model has been performed; the outcome variable was the surgical intervention. For each predictive variable, Odds Ratio and 95% Confidence Intervals were calculated. The likelihood ratio test was used to assess the significance of the variables. Using the regression model, we assigned a numerical value to each predictive variable, rounding up the beta-coefficients. The cut-off value of the total score was obtained from the ROC curve analysis. Results: A total of 192 patients were enrolled, corresponding to 200 pathological kidneys. All of them underwent fMRU; 135 were surgically treated, while 65 underwent ultrasound or MRU follow-up. Predictive variables significantly associated with surgery resulted to be the urographic phase, the presence of abnormal vessels, and a baseline anterior-posterior pelvic diameter >23 mm. Beta coefficients of the logistic regression model were then converted in scores. The ROC curve of the score showed high sensitivity (84.3%) and specificity (81.3%) with a cut-off > 2.5. Conclusions: We propose a new fMRU score able to identify surgical vs. non-surgical kidneys with UPJO.
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Congenital abnormalities of the kidney and urinary tract include a wide range of malformations ranging from asymptomatic to life-threatening conditions. Although pediatric urogenital system imaging is based on the use of US (pre- and postnatal), voiding cystourethrography and scintigraphic study, magnetic resonance (MR) urography plays a fundamental role in the classification and management of congenital abnormalities of the kidney and urinary tract, giving an overview of the different clinical pictures, thanks to its panoramicity and high anatomical detail. In fact the anomalies of the urinary tract are phenotypically variable because they can affect simultaneously several segments of different embryonic derivation, with complex clinical pictures; they can appear both as isolated phenotypes or as complex malformative conditions, involving renal parenchyma, collecting system and bladder. A deep knowledge of this complex embryogenesis and its possible phenotypic patterns allows a correct interpretation of MR urography images. We describe the embryology and pathophysiology of congenital abnormalities of the kidney and urinary tract as well as MR urography technique and findings. Congenital abnormalities of the kidney and urinary tract are classified into four groups: (1) obstruction (proximal, middle and distal), (2) budding with respect to the Wolffian duct (site and number of ureter), (3) ascent and rotation (ectopia, malrotation and fusion of kidney) and (4) anomaly of metanephric differentiation (dysplasia, megapolicalycosis).
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Sistema Urinário , Urografia , Criança , Humanos , Rim/anormalidades , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Radiologistas , Sistema Urinário/diagnóstico por imagem , Urografia/métodosRESUMO
Ultrasound is very effective in performing procedures and assessment of complications in peritoneal dialysis. The ultrasound examination can be applied for preoperative assessment, during the peritoneal catheter placement, for the detection and monitoring of infection, as well as for the evaluation of the catheter malfunction. Despite being not only a cost- and time-saving technique but also a bedside procedure, ultrasonography remains an underrated clinical tool in the field of peritoneal dialysis. This publication wants to explain and reinforce the clinical utility of US in PD and to expand the diagnostic equipment for the clinician.
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Falência Renal Crônica , Diálise Peritoneal , Cateteres de Demora , Humanos , Falência Renal Crônica/diagnóstico por imagem , Falência Renal Crônica/terapia , UltrassonografiaRESUMO
Objectives: The study aimed to characterize the clonal spread of resistant bacteria and dissemination of resistance plasmids among carbapenem-resistant Enterobacterales at a tertiary hospital in Catalonia, Spain. Methods: Isolates were recovered from surveillance rectal swabs and diagnostic samples. Species identification was by matrix-assisted laser desorption ionization-time time of flight mass spectrometry (MALDI-TOF MS). Molecular typing was performed by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). Antimicrobial susceptibility was assessed by gradient-diffusion and carriage of bla genes was detected by PCR. Plasmid typing, conjugation assays, S1-PFGE studies and long-read sequencing were used to characterize resistance plasmids. Results: From July 2018 to February 2019, 125 Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacterales were recovered from 101 inpatients from surveillance (74.4%) or clinical samples (25.6%), in a tertiary hospital in Barcelona. Clonality studies identified a major clone of Klebsiella pneumoniae belonging to sequence type ST15 and additional isolates of K. pneumoniae, Escherichia coli and Enterobacter sp. from different STs. All isolates but one carried the bla KPC-2 allelic variant. The bla KPC-2 gene was located in an IncFIIk plasmid of circa 106 Kb in a non-classical Tn4401 element designated NTEKPC-pMC-2-1. Whole-genome sequencing revealed different rearrangements of the 106 Kb plasmid while the NTEKPC-pMC-2-1 module was highly conserved. Conclusion: We report a hospital outbreak caused by the clonal dissemination of KPC-producing ST15 K. pneumoniae but also the intra- and inter-species transmission of the bla KPC-2 gene associated with plasmid conjugation and/or transposon dissemination. To our knowledge, this is the first report of an outbreak caused by KPC-producing Enterobacterales isolated from human patients in Catalonia and highlights the relevance of surveillance studies in the early detection and control of antibiotic resistant high-risk clones.
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Gray scale ultrasound has an important diagnostic role in native kidney disease. Low cost, absence of ionizing radiation and nephrotoxicity, short performance time, and repeatability even at the bedside, are the major advantages of this technique. The introduction of contrast enhancement ultrasound (CEUS) in daily clinical practice has significantly reduced the use of contrast enhancement computed tomography (CECT) and contrast enhancement magnetic resonance (CEMR), especially in patients with renal disease. Although there are many situations in which CECT and CEMRI are primarily indicated, their use may be limited by the administration of the contrast medium, which may involve a risk of renal function impairment, especially in the elderly, and in patients with acute kidney injury (AKI) and moderate to severe chronic kidney disease (CKD). In these cases, CEUS can be a valid diagnostic choice. To date, numerous publications have highlighted the role of CEUS in the study of parenchymal micro-vascularization and renal pathology by full integration with second level imaging methods (CECT and CEMRI) both in patients with normal renal function and with diseased kidneys. The aim of this review is to offer an updated overview of the limitations and potential applications of CEUS in native kidney disease.
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INTRODUCTION: To investigate how long successfully ablated tumours take to become completely avascular at CEUS after cryoablation. METHODS: Ninety-five patients had percutaneous cryoablation of 103 renal tumours investigated at CEUS on post-operative day one. If the lesion was avascular, a contrast-CT/MR was scheduled six months after the procedure, while CEUS was repeated if the lesion still displayed enhancement, until the disappearance of intralesional vascularity. Technical success was defined when the tumour was covered completely by the ablation zone. Technique efficacy was assessed at six months of follow-up. RESULTS: Technical efficacy was obtained for 101/103 cryoablations, 56% of which (57/101) were avascular on post-operative day one. After one week, two weeks, one month 83%, 91% and 100% of these 101 lesions, respectively, were avascular. Two tumours were unsuccessfully treated. They displayed persistent intralesional vascularity at CEUS one month after the procedure. CONCLUSIONS: After cryoablation, obtaining CEUS before one month may be misleading. When technical efficacy is obtained, disappearance of intralesional enhancement is observed within two weeks in the majority of cases (91%), but can persist until one month. Identification of tumour enhancement after one month may be concerning for residual viable tumour.
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Criocirurgia , Neoplasias Renais , Meios de Contraste , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , UltrassonografiaRESUMO
Imaging plays a crucial role in the evaluation of scrotal trauma. Among the imaging modalities, greyscale ultrasound and Colour Doppler ultrasound (CDUS) are the primary techniques with the selective utilisation of advanced techniques such as contrast-enhanced ultrasound (CEUS) and elastography. Despite ultrasound being the mainstay of imaging scrotal trauma, its diagnostic performance is not fully established. Considering these difficulties and their impact on clinical practice, the Scrotal and Penile Imaging Working Group of the European Society of Urogenital Radiology (ESUR-SPIWG) established an expert task force to review the current literature and consolidate their expertise on examination standards and imaging appearances of various entities in scrotal trauma. This paper provides the position statements agreed on by the task force with the aim of providing guidance for the use of imaging especially multiparametric US in scrotal trauma.Key Points⢠Greyscale and Colour Doppler ultrasound are the mainstay of imaging in patients with scrotal trauma.⢠Contrast-enhanced ultrasound and elastography are the advanced techniques useful as a problem-solving modality in equivocal cases.⢠This paper summarises the position statements of the ESUR-SPIWG on the appropriate utilisation of multiparametric ultrasound and other imaging modalities in the evaluation of scrotal trauma.
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Radiologia , Escroto , Humanos , Masculino , Pênis/diagnóstico por imagem , Radiografia , Escroto/diagnóstico por imagem , UltrassonografiaRESUMO
Acute scrotum is characterized by intense acute scrotal pain, which may be associated with other symptoms and signs such as abdominal pain, inflammation, and fever. Many pathologic conditions can present in this way, most which involve the scrotal contents. Nonscrotal conditions, however, can rarely present clinically only as acute scrotum: among them, renal colic, aneurysm rupture or other causes of retroperitoneal hemorrhage, primary abdominal or pelvic tumors and metastases, pancreatitis, pelvic inflammation, and muscle injuries. The pathophysiologic characteristics of the clinical presentation, clues for diagnosis, and imaging features of a series of nonscrotal lesions presenting clinically with acute scrotal pain are herein reported and illustrated. In patients presenting with acute scrotal symptoms and normal scrotal ultrasound findings, nonscrotal causes of acute scrotal pain should be considered in the differential diagnosis. Therefore, an ultrasound investigation of the abdomen, groin, and thighs is indicated.
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Doenças dos Genitais Masculinos , Escroto , Doença Aguda , Diagnóstico Diferencial , Doenças dos Genitais Masculinos/diagnóstico por imagem , Hemorragia , Humanos , Masculino , Escroto/diagnóstico por imagem , UltrassonografiaRESUMO
OBJECTIVES: To characterize the clonal spread of carbapenem-resistant Klebsiella pneumoniae and Escherichia coli isolates between different healthcare institutions in Catalonia, Spain. METHODS: Antimicrobial susceptibility was tested by disc diffusion. MICs were determined by gradient diffusion or broth microdilution. Carbapenemase production was confirmed by lateral flow. PCR and Sanger sequencing were used to identify the allelic variants of resistance genes. Clonality studies were performed by PFGE and MLST. Plasmid typing, conjugation assays, S1-PFGE plus Southern blotting and MinION Oxford Nanopore sequencing were used to characterize resistance plasmids. RESULTS: Twenty-nine carbapenem-resistant isolates recovered from three healthcare institutions between January and November 2016 were included: 14 K. pneumoniae isolates from a tertiary hospital in the south of Catalonia (hospital A); 2 K. pneumoniae isolates from a nearby healthcare centre; and 12 K. pneumoniae isolates and 1 E. coli isolate from a tertiary hospital in Barcelona (hospital B). The majority of isolates were resistant to all antimicrobial agents, except colistin, and all were NDM producers. PFGE identified a major K. pneumoniae clone (n = 27) belonging to ST147 and co-producing NDM-1 and CTX-M-15, with a few isolates also harbouring blaOXA-48. Two sporadic isolates of K. pneumoniae ST307 and E. coli ST167 producing NDM-7 were also identified. blaNDM-1 was carried in two related IncR plasmid populations and blaNDM-7 in a conjugative 50 kb IncX3 plasmid. CONCLUSIONS: We report the inter-hospital dissemination of XDR high-risk clones of K. pneumoniae and E. coli associated with the carriage of small, transferable plasmids harbouring blaNDM genes.
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Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Células Clonais , Infecção Hospitalar/microbiologia , Escherichia coli/genética , Humanos , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Plasmídeos/genética , Espanha/epidemiologia , beta-Lactamases/genéticaRESUMO
BACKGROUND: Ultrasonography (US) is highly dependent on operators' skills. It is not only a matter of correct scan techniques; there are anatomical structures and variants, as well as artifacts, which can produce images difficult to interpret and which, if not properly understood, can be causes of errors. OBJECTIVES: This paper will review relatively common US pitfalls and artifacts that can be encountered in trauma patients and will offer tips to recognize and avoid them. DISCUSSION: Normal anatomical structures and anatomical variants can mimic fluid collections or perisplenic lesions. Examination along multiple scan planes, real-time observation of movements or repetition of the study after the patient has drunk some fluid or after placing a finger on her/his body wall can help proper identification. The term artifact in US imaging refers to display phenomena not properly representing the imaged structures. This can result in images suggesting fracture lines within organs or at their borders, lung consolidations, or pleural effusions, and abdominal fluid collections. Their knowledge is the first step to recognize them; then, use of multiple scan planes or repetition of the study after voiding or changes of equipment setting can make them disappear or clarify their nature. CONCLUSION: We present possible anatomic pitfalls and artifacts that may affect correct interpretation of US images in patients with abdominal trauma and suggest how to avoid or to clarify them during the examination. Knowing their existence, their appearances, and the reasons why they are produced is important for proper use of this diagnostic technique.
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Traumatismos Abdominais , Artefatos , Feminino , Humanos , Movimento , UltrassonografiaRESUMO
Plasmids, when transferred by conjugation in natural environments, must overpass restriction-modification systems of the recipient cell. We demonstrate that protein ArdC, encoded by broad host range plasmid R388, was required for conjugation from Escherichia coli to Pseudomonas putida. Expression of ardC was required in the recipient cells, but not in the donor cells. Besides, ardC was not required for conjugation if the hsdRMS system was deleted in P. putida recipient cells. ardC was also required if the hsdRMS system was present in E. coli recipient cells. Thus, ArdC has antirestriction activity against the HsdRMS system and consequently broadens R388 plasmid host range. The crystal structure of ArdC was solved both in the absence and presence of Mn2+. ArdC is composed of a non-specific ssDNA binding N-terminal domain and a C-terminal metalloprotease domain, although the metalloprotease activity was not needed for the antirestriction function. We also observed by RNA-seq that ArdC-dependent conjugation triggered an SOS response in the P. putida recipient cells. Our findings give new insights, and open new questions, into the antirestriction strategies developed by plasmids to counteract bacterial restriction strategies and settle into new hosts.