RESUMEN
Antimicrobial resistance (AMR) has emerged as a significant global healthcare problem. Antibiotic use has accelerated the physiologic process of AMR, particularly in Gram-negative pathogens. Urinary tract infections (UTIs) are predominantly of a Gram-negative nature. Uropathogens are evolutionarily highly adapted and selected strains with specific virulence factors, suggesting common mechanisms in how bacterial cells acquire virulence and AMR factors. The simultaneous increase in resistance and virulence is a complex and context-dependent phenomenon. Among known AMR mechanisms, the plenitude of different ß-lactamases is especially prominent. The risk for AMR in UTIs varies in different patient populations. A history of antibiotic consumption and the physiology of urinary flow are major factors that shape AMR prevalence. The urinary tract is in close crosstalk with the microbiome of other compartments, including the gut and genital tracts. In addition, pharmacokinetic properties and the physiochemical composition of urinary compartments can contribute to the emergence of AMR. Alternatives to antibiotic treatment and a broader approach to address bacterial infections are needed. Among the various alternatives studied, antimicrobial peptides and bacteriophage treatment appear to be highly promising approaches. We herein summarize the present knowledge of clinical and microbiological AMR in UTIs and discuss innovative approaches, namely new risk prediction tools and the use of non-antibiotic approaches to defend against uropathogenic microbes.
Asunto(s)
Infecciones Urinarias , Sistema Urinario , Humanos , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana , Infecciones Urinarias/tratamiento farmacológicoRESUMEN
TcpC is a virulence factor of uropathogenic E. coli (UPEC). It was found that TIR domain of TcpC impedes TLR signaling by direct association with MyD88. It has been a long-standing question whether bacterial pathogens have evolved a mechanism to manipulate MyD88 degradation by ubiquitin-proteasome pathway. Here, we show that TcpC is a MyD88-targeted E3 ubiquitin ligase. Kidney macrophages from mice with pyelonephritis induced by TcpC-secreting UPEC showed significantly decreased MyD88 protein levels. Recombinant TcpC (rTcpC) dose-dependently inhibited protein but not mRNA levels of MyD88 in macrophages. Moreover, rTcpC significantly promoted MyD88 ubiquitination and accumulation in proteasomes in macrophages. Cys12 and Trp106 in TcpC are crucial amino acids in maintaining its E3 activity. Therefore, TcpC blocks TLR signaling pathway by degradation of MyD88 through ubiquitin-proteasome system. Our findings provide not only a novel biochemical mechanism underlying TcpC-medicated immune evasion, but also the first example that bacterial pathogens inhibit MyD88-mediated signaling pathway by virulence factors that function as E3 ubiquitin ligase.
Asunto(s)
Proteínas de Escherichia coli/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , Transducción de Señal/fisiología , Escherichia coli Uropatógena/patogenicidad , Factores de Virulencia/metabolismo , Animales , Línea Celular , Femenino , Humanos , Evasión Inmune/fisiología , Macrófagos , Ratones , Ratones Endogámicos C57BL , Pielonefritis/inmunología , Pielonefritis/microbiología , Receptores Toll-Like/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Escherichia coli Uropatógena/inmunología , Escherichia coli Uropatógena/metabolismo , Virulencia/fisiologíaRESUMEN
The TIR-containing protein C (TcpC) of the uropathogenic Escherichia coli strain CFT073 modulates innate immunity by interfering with the Toll-like receptor and NALP3 inflammasome signaling cascade. During a urinary tract infection the pathogen encounters epithelial and innate immune cells and replicates by several orders of magnitude. We therefore analyzed whether these cell types and also the density of the pathogen would induce the recently defined promoter of the CFT073 tcpC gene to, in time, dampen innate immune responses. Using reporter constructs we found that the uroepithelial cell line T24/83 and the monocytic cell line THP-1 induced the tcpC promoter. Differentiation of monocytic THP-1 cells to macrophages increased their potential to switch on the promoter. Cell-associated CFT073 displayed the highest promoter activity. Since potassium represents the most abundant intracellular ion and is secreted to induce the NLRP3 inflammasome, we tested its ability to activate the tcpC promoter. Potassium induced the promoter with high efficiency. Sodium, which is enriched in the renal cortex generating an antibacterial hypersalinity, also induced the tcpC promoter. Finally, the bacterial density modulated the tcpC promoter activity. In the search for promoter-regulating proteins, we found that the DNA-binding protein H-NS dampens the promoter activity. Taken together, different cell types and salts, present in the kidney, are able to induce the tcpC promoter and might explain the mechanism of TcpC induction during a kidney infection with uropathogenic E. coli strains.
Asunto(s)
Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas Fimbrias/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Infecciones Urinarias/microbiología , Escherichia coli Uropatógena/patogenicidad , Factores de Virulencia/genética , Diferenciación Celular/efectos de los fármacos , Línea Celular , Regulación Bacteriana de la Expresión Génica , Humanos , Inflamasomas/metabolismo , Modelos Biológicos , Potasio/farmacología , Regiones Promotoras Genéticas/efectos de los fármacos , Transducción de Señal , Sodio/farmacología , Células THP-1 , Infecciones Urinarias/metabolismo , Escherichia coli Uropatógena/genética , Factores de Virulencia/metabolismoRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide, with about 841,000 new cases and 782,000 deaths annually. Given the clearly defined population at risk, mostly patients with liver cirrhosis, prevention of HCC could be highly effective. SUMMARY: Besides regular ultrasound surveillance, numerous publications have suggested protective effects of diverse drugs and nutrients. However, none of those preventive options has made it into clinical routine or practice guidelines. We therefore summarize the current status of preventive effects of drugs such as statins, acetylsalicylic acid (ASA), and metformin, but also dietary aspects and nutrients such as coffee, tea, and vitamin D supplementation. A successful implementation of some of these strategies may potentially lead to improved prevention of HCC development in patients with liver cirrhosis. Key Messages: Accumulating data suggest that particularly ASA, antidiabetic therapies, and statins may substantially decrease HCC incidence in patients at risk.
Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/prevención & control , Humanos , Hipoglucemiantes , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/prevención & control , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/prevención & control , Factores de RiesgoRESUMEN
BACKGROUND: The unexpected outbreak of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused more than 49 million cases and an estimated 2,000,000 associated deaths worldwide. In Germany, there are currently more than 2,000,000 laboratory-confirmed coronavirus disease 2019 (COVID-19) cases including 51,800 deaths. However, regional differences also became apparent and with the second wave of infections, the detailed characterization of COVID-19 patients is crucial to early diagnosis and disruption of chains of infections. METHODS: Handing out detailed questionnaires to all individuals tested for COVID-19, we evaluated the clinical characteristics of negative and positive tested individuals. Expression of symptoms, symptom duration and association between predictor variables (i.e. age, gender) and a binary outcome (olfactory and gustatory dysfunction) were assessed. RESULTS: Overall, the most common symptoms among individuals who tested positive for SARS-CoV-2 were fatigue, headache, and cough. Olfactory and gustatory dysfunction were also reported by many SARS-CoV-2 negative individuals, more than 20% of SARS-CoV-2 negative tested individuals in our study reported olfactory and gustatory dysfunction. Independent of SARS-CoV-2 status, more females displayed symptoms of gustatory (29.8%, p = 0.0041) and olfactory dysfunction (22.9%, p = 0.0174) compared to men. CONCLUSIONS: Bringing early SARS-CoV-2 tests to the populations at risk must be a main focus for the upcoming months. The reliability of olfactory and gustatory dysfunction in COVID-19 negative tested individuals requires deeper investigation in the future.
Asunto(s)
COVID-19/epidemiología , COVID-19/virología , Trastornos del Olfato/epidemiología , Trastornos del Olfato/virología , Trastornos del Gusto/epidemiología , Trastornos del Gusto/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/fisiopatología , Tos/epidemiología , Diagnóstico Precoz , Fatiga/epidemiología , Femenino , Alemania/epidemiología , Cefalea/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Olfato/diagnóstico , Trastornos del Olfato/fisiopatología , Pandemias , Reproducibilidad de los Resultados , SARS-CoV-2/patogenicidad , Caracteres Sexuales , Olfato , Encuestas y Cuestionarios , Trastornos del Gusto/fisiopatología , Adulto JovenRESUMEN
The dissemination of carbapenem-producing Gram-negative bacteria is a major public health concern. We report the first detection of OXA-244-producing ST131 O16:H5 Escherichia coli in three patients from two tertiary hospitals in the south-west of Germany. OXA-244 is emerging in Europe. Because of detection challenges, OXA-244-producing E. coli may be under-reported. The emergence of carbapenem resistance in a globally circulating high-risk clone, such as ST131 E. coli is of clinical relevance and should be monitored closely.
Asunto(s)
Carbapenémicos , Farmacorresistencia Bacteriana , Infecciones por Escherichia coli , Escherichia coli , Adulto , Anciano , Carbapenémicos/farmacología , Niño , Farmacorresistencia Bacteriana/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/epidemiología , Alemania/epidemiología , Humanos , Persona de Mediana Edad , Adulto JovenRESUMEN
Background The increasing number of multi-drug resistant (MDR) bacteria provides enormous challenges for choosing an appropriate antibiotic therapy in the early phase of sepsis. While bacterial identification has been greatly accelerated by the introduction of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), the antibiotic susceptibility testing (AST) remains time-consuming. Here, we present a rapid susceptibility testing method for testing Gram-negative bacteria, exemplarily validated for Escherichia coli and Klebsiella spp. Methods Gram-negative isolates (E. coli and Klebsiella spp.) were either taken as single colonies from agar plates (n=136) or directly extracted and identified from positive blood cultures (n=42) using MALDI-TOF MS. Bacteria were incubated in glucose-supplemented Luria broths (LBs) each containing one antibiotic (ceftazidime, piperacillin, imipenem and ciprofloxacin), routinely used to classify Gram-negative bacteria in Germany. To determine susceptibility the dynamics of glucose utilization in bacterial suspensions were quantitatively measured in the presence or absence of antibiotics designated liquid-AST (L-AST). Results The L-AST can be run on clinical-chemistry analyzers and integrated into laboratory routines. It yields critical resistance information within 90-150 min downstream of a MS-based identification. The results showed a high concordance with routine susceptibility testing, with less than 1% very major errors (VME) and 3.51% major errors (ME) for 178 assessed isolates. Analysis of turnaround time (TAT) for 42 clinical samples indicated that L-AST results could be obtained 34 h earlier than the routine results. Conclusions As exemplified for E. coli and Klebsiella spp., L-AST provides substantial acceleration of susceptibility testing following MALDI-TOF MS identification. The assay is a simple and low-cost method that can be integrated into clinical laboratory to allow for 24/7 AST. This approach could improve antibiotic therapy.
Asunto(s)
Pruebas de Química Clínica , Escherichia coli/aislamiento & purificación , Glucosa/análisis , Glucosa/metabolismo , Klebsiella/aislamiento & purificación , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Humanos , Klebsiella/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Tissue damage is usually regarded as a necessary price to pay for successful elimination of pathogens by the innate immune defense. Yet, it is possible to distinguish protective from destructive effects of innate immune activation and selectively attenuate molecular nodes that create pathology. Here, we identify acute cystitis as an Interleukin-1 beta (IL-1ß)-driven, hyper-inflammatory condition of the infected urinary bladder and IL-1 receptor blockade as a novel therapeutic strategy. Disease severity was controlled by the mechanism of IL-1ß processing and mice with intact inflammasome function developed a moderate, self-limiting form of cystitis. The most severe form of acute cystitis was detected in mice lacking the inflammasome constituents ASC or NLRP-3. IL-1ß processing was hyperactive in these mice, due to a new, non-canonical mechanism involving the matrix metalloproteinase 7- (MMP-7). ASC and NLRP-3 served as transcriptional repressors of MMP7 and as a result, Mmp7 was markedly overexpressed in the bladder epithelium of Asc-/- and Nlrp3-/- mice. The resulting IL-1ß hyper-activation loop included a large number of IL-1ß-dependent pro-inflammatory genes and the IL-1 receptor antagonist Anakinra inhibited their expression and rescued susceptible Asc-/- mice from bladder pathology. An MMP inhibitor had a similar therapeutic effect. Finally, elevated levels of IL-1ß and MMP-7 were detected in patients with acute cystitis, suggesting a potential role as biomarkers and immunotherapeutic targets. The results reproduce important aspects of human acute cystitis in the murine model and provide a comprehensive molecular framework for the pathogenesis and immunotherapy of acute cystitis, one of the most common infections in man. TRIAL REGISTRATION: The clinical studies were approved by the Human Ethics Committee at Lund University (approval numbers LU106-02, LU236-99 and Clinical Trial Registration RTP-A2003, International Committee of Medical Journal Editors, www.clinicaltrials.gov).
Asunto(s)
Cistitis/genética , Cistitis/inmunología , Interleucina-1beta/inmunología , Metaloproteinasa 7 de la Matriz/inmunología , Enfermedad Aguda , Animales , Western Blotting , Modelos Animales de Enfermedad , Ensayo de Cambio de Movilidad Electroforética , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Inmunoprecipitación , Interleucina-1beta/genética , Masculino , Metaloproteinasa 7 de la Matriz/genética , Ratones , Ratones Endogámicos C57BL , Microscopía Confocal , Reacción en Cadena de la Polimerasa , Transcriptoma , TransfecciónRESUMEN
OBJECTIVE: Multidrug-resistant organisms (MDRO) are a challenge in allogeneic hematopoietic cell transplantation (HCT). However, in the literature there is no comprehensive analysis on MDRO in HCT. In this retrospective, single-center analysis, we appraised prevalence and clinical impact of MDRO in 98 consecutive allogeneic HCT patients. METHOD: Prior to the conditioning (baseline) and whenever clinically indicated patients underwent a full screening for MDRO (stool and urine cultures, swabs from several body regions). RESULTS: It turned out that 26 patients were colonized by 33 MDRO, either at baseline (n=16) or at any other time until day 100 post-transplantation. Of these 26 patients, eight developed an infection with MDRO, four of them by 4MRGN Pseudomonas aeruginosa, and three of them died MDRO-related. However, there was no significant difference between MDRO-colonized and non-colonized patients regarding overall survival (OS) and non-relapse-mortality (NRM). There was only a trend toward a higher NRM in patients already colonized by MDRO at baseline. This was due to the high NRM in multidrug-resistant P. aeruginosa-colonized patients. CONCLUSION: In summary, colonization with MDRO other than P. aeruginosa had no negative impact on NRM and OS. Patients colonized by multidrug-resistant P. aeruginosa had a dismal outcome. HCT of these patients should be considered with care. Screening for MDRO in the pretransplant work-up is suggested.
Asunto(s)
Farmacorresistencia Microbiana , Resistencia a Múltiples Medicamentos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Infecciones/epidemiología , Infecciones/etiología , Adulto , Anciano , Antiinfecciosos/farmacología , Manejo de la Enfermedad , Neutropenia Febril/diagnóstico , Neutropenia Febril/etiología , Neutropenia Febril/terapia , Femenino , Humanos , Infecciones/diagnóstico , Infecciones/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Mortalidad , Prevalencia , Estudios Retrospectivos , Acondicionamiento Pretrasplante/efectos adversos , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo , Adulto JovenRESUMEN
Invasive pulmonary aspergillosis (IPA) is a life-threatening infection mainly affecting immunocompromised patients. Early diagnosis is critical, but the diagnostic gold standard (histopathology and culture) is time consuming and cannot offer early confirmation of IPA. Fungal biomarkers like galactomannan (GM) are a promising extension to the diagnostic repertoire. However, it still remains under discussion if biomarker analysis from the site of the infection is superior to testing blood samples. We retrospectively evaluated the diagnostic performance of concurrent serum GM and bronchoalveolar lavage (BAL) GM (obtained within 24 h) of immunocompromised patients at high risk of IPA. Twenty-six proven/probable patients and eight patients with no IPA according to the EORTC/MSG 2008 criteria were included in this study. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic odds ratio were for BAL GM: 85%, 88%, 96%, 64% and 38.5, and for serum GM: 23%, 88%, 88%, 26% and 2.1 respectively. BAL GM proved to be significantly more sensitive for the detection of IPA compared to same-day serum GM in patients at high risk of IPA (P < 0.0001). Our data show that BAL GM testing is significantly superior to serum GM implying that diagnostic efforts should focus on specimens from the site of infection.
Asunto(s)
Aspergillus/inmunología , Lavado Broncoalveolar/métodos , Huésped Inmunocomprometido , Aspergilosis Pulmonar Invasiva/diagnóstico , Mananos/sangre , Adulto , Anciano , Antígenos Fúngicos/sangre , Biomarcadores/sangre , Líquido del Lavado Bronquioalveolar/inmunología , Diagnóstico Precoz , Ensayo de Inmunoadsorción Enzimática , Femenino , Galactosa/análogos & derivados , Humanos , Aspergilosis Pulmonar Invasiva/inmunología , Masculino , Mananos/inmunología , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
The Toll/IL-1 receptor (TIR) domains are crucial signaling modules during innate immune responses involving the Toll-like receptors (TLRs) and IL-1 receptor (IL-1R). Myeloid differential factor 88 (MyD88) is a central TIR domain-containing adapter molecule responsible for nearly all TLR-mediated signaling and is targeted by a TIR domain-containing protein C (TcpC) from virulent uropathogenic Escherichia coli, a common human pathogen. The mechanism of such molecular antagonism has remained elusive. We present the crystal structure of the MyD88 TIR domain with distinct loop conformations that underscore the functional specialization of the adapter, receptor, and microbial TIR domains. Our structural analyses shed light on the genetic mutations at these loops as well as the Poc site. We demonstrate that TcpC directly associates with MyD88 and TLR4 through its predicted DD and BB loops to impair the TLR-induced cytokine induction. Furthermore, NMR titration experiments identify the unique CD, DE, and EE loops from MyD88 at the TcpC-interacting surface, suggesting that TcpC specifically engages these MyD88 structural elements for immune suppression. These findings thus provide a molecular basis for the subversion of TLR signaling by the uropathogenic E. coli virulence factor TcpC and furnish a framework for the design of novel therapeutic agents that modulate immune activation.
Asunto(s)
Proteínas de Escherichia coli/inmunología , Escherichia coli/inmunología , Inmunidad Innata/inmunología , Modelos Moleculares , Factor 88 de Diferenciación Mieloide/inmunología , Conformación Proteica , Transducción de Señal/inmunología , Factores de Virulencia/inmunología , Cristalografía , Humanos , Luciferasas , Espectroscopía de Resonancia Magnética , Simulación de Dinámica Molecular , Mutación/genética , Factor 88 de Diferenciación Mieloide/química , Factor 88 de Diferenciación Mieloide/genética , Receptores de Interleucina-1/inmunología , Receptores Toll-Like/inmunologíaRESUMEN
The Toll/IL-1 receptor (TIR) domains are crucial innate immune signaling modules. Microbial TIR domain-containing proteins inhibit Toll-like receptor (TLR) signaling through molecular mimicry. The TIR domain-containing protein TcpB from Brucella inhibits TLR signaling through interaction with host adaptor proteins TIRAP/Mal and MyD88. To characterize the microbial mimicry of host proteins, we have determined the X-ray crystal structures of the TIR domains from the Brucella protein TcpB and the host adaptor protein TIRAP. We have further characterized homotypic interactions of TcpB using hydrogen/deuterium exchange mass spectrometry and heterotypic TcpB and TIRAP interaction by co-immunoprecipitation and NF-κB reporter assays. The crystal structure of the TcpB TIR domain reveals the microtubule-binding site encompassing the BB loop as well as a symmetrical dimer mediated by the DD and EE loops. This dimerization interface is validated by peptide mapping through hydrogen/deuterium exchange mass spectrometry. The human TIRAP TIR domain crystal structure reveals a unique N-terminal TIR domain fold containing a disulfide bond formed by Cys(89) and Cys(134). A comparison between the TcpB and TIRAP crystal structures reveals substantial conformational differences in the region that encompasses the BB loop. These findings underscore the similarities and differences in the molecular features found in the microbial and host TIR domains, which suggests mechanisms of bacterial mimicry of host signaling adaptor proteins, such as TIRAP.
Asunto(s)
Proteínas Bacterianas/química , Glicoproteínas de Membrana/química , Estructura Terciaria de Proteína , Receptores de Interleucina-1/química , Factores de Virulencia/química , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión/genética , Brucella melitensis/genética , Brucella melitensis/metabolismo , Cristalografía por Rayos X , Células HEK293 , Humanos , Immunoblotting , Inmunoprecipitación , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Modelos Moleculares , Imitación Molecular , Datos de Secuencia Molecular , Unión Proteica , Conformación Proteica , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo , Homología de Secuencia de Aminoácido , Transducción de Señal , Receptores Toll-Like/metabolismo , Factores de Virulencia/genética , Factores de Virulencia/metabolismoRESUMEN
Inhibitory TLR7 and/or TLR9 oligonucleotides (inhibitory oligonucleotide [INH-ODN]) are characterized by a phosphorothioate backbone and a CC(T)XXX3â5GGG motif, respectively. INH-ODN 2088 is a prototypic member of this class of INH-ODN and acts as a TLR7 and TLR9 antagonist. It contains a G quadruple that leads to higher order structures by the formation of G tetrads. These structures are unfavorable for the prediction of their pharmacological and immunological behavior. We show in this study that modification of Gs within the G quadruple by 7-deaza-guanine or 7-deaza-2'-O-methyl-guanine avoids higher order structures and improves their inhibitory potential. Whereas TLR9-induced TNF-α secretion of bone marrow-derived macrophages and conventional dendritic cells was equally inhibited by INH-ODN 2088 and G-modified INH-ODNs such as INH-ODN 24888, TLR7-induced TNF-α release and TLR7- and TLR9-induced IL-12p40 release were significantly more impaired by G-modified INH-ODNs. Similarly, the IL-6 release of B cells from wild-type and autoimmune MRL/Mp-lpr/lpr mice was more efficiently impaired by G-modified INH-ODNs. Surprisingly, INH-ODN 2088 stimulated B cells to proliferate when used in higher doses. Finally, in vivo, in wild-type and autoimmune MRL/Mp-lpr/lpr mice, G-modified INH-ODN 24888 was significantly more efficient than unmodified INH-ODN 2088. In summary, G modification allows the development of INH-ODNs with superior inhibitory potency for inflammatory diseases with high medical need such as systemic lupus erythematosus.
Asunto(s)
Guanina/química , Tolerancia Inmunológica/efectos de los fármacos , Oligonucleótidos/química , Oligonucleótidos/farmacología , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Proliferación Celular/efectos de los fármacos , Citocinas/biosíntesis , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Tolerancia Inmunológica/inmunología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Glicoproteínas de Membrana/antagonistas & inhibidores , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos MRL lpr , Receptor Toll-Like 7/antagonistas & inhibidores , Receptor Toll-Like 9/antagonistas & inhibidoresRESUMEN
Periprosthetic joint infections (PJI) pose a significant challenge in orthopaedic surgery, often requiring extensive surgical debridement and prolonged antibiotic treatment to eliminate the causative pathogens. Rifampin, known for its potent activity against biofilms, has been crucial in managing PJI by penetrating and disrupting these formations, thereby improving treatment efficacy. In this sense, antibiotic protocols lacking rifampin have shown increased failure rates. Consequently, the development of rifampin resistance could severely influence the prognosis of PJI. The aim of this clinical study was to assess how rifampin resistance affects the functional outcome in patients with PJI. In this single-centre comparative cohort study, we systematically documented all patients who presented with a PJI during the period spanning from 2018 to 2020. Two distinct groups were established for the study: Group 1 comprised 35 patients with a PJI caused by rifampin-susceptible pathogens and group 2 consisted of 28 patients with PJI caused by rifampin-resistant pathogens. A total of 63 patients (34 females) with a mean age of 68 years and a mean follow up of 37 months were included. The examination of patient-specific parameters did not reveal any identified risk factors as influential. Patients with a rifampin-resistant pathogen underwent a greater number of surgical revisions (6.9 ± 5.1 compared to 3.59 ± 3.39, p = 0.0011) and had extended durations of antibiotic treatment (p = 0.0052). The results of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score revealed significant differences in clinical outcome between both groups in every domain, even when stratified by acute and chronic entities. In total the WOMAC increased significantly from 21.57 ± 14.9 points in group 1 to 71.47 ± 62.7 points in group 2 (p < 0.001). The higher failure rates observed in group 2 were not statistically significant (p = 0.44). The current study demonstrates that PJI caused by rifampin-resistant bacteria are associated with a significantly worse functional outcome in both acute and chronic infection types without significantly affecting total failure rates.
RESUMEN
BACKGROUND: Chronic osteomyelitis due to direct bone trauma or vascular insufficiency is a frequent problem in orthopaedic surgery. In contrast, acute haematogenous osteomyelitis represents a rare entity that almost exclusively affects prepubescent children or immunodeficient adults. CASE PRESENTATION: In this article, we report the case of acute pneumococcal osteomyelitis of the humerus in an immunocompetent and otherwise healthy 44-year-old male patient presenting with minor inflammation signs and misleading clinical features. CONCLUSIONS: The diagnosis had to be confirmed by open biopsy which allowed the initiation of a targeted therapy. A case of pneumococcal osteomyelitis of a long bone, lacking predisposing factors or trauma, is unique in adults and has not been reported previously.
Asunto(s)
Húmero/patología , Osteomielitis/diagnóstico , Infecciones Neumocócicas/diagnóstico , Streptococcus pneumoniae/aislamiento & purificación , Enfermedad Aguda , Adulto , Diagnóstico Diferencial , Humanos , Húmero/diagnóstico por imagen , Húmero/microbiología , Inmunocompetencia , Imagen por Resonancia Magnética , Masculino , RadiografíaAsunto(s)
Bacterias/aislamiento & purificación , Técnicas Bacteriológicas/métodos , Cultivo de Sangre/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Bacteriemia/diagnóstico , Bacteriemia/microbiología , Bacterias/clasificación , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Choque Séptico/diagnóstico , Choque Séptico/microbiologíaRESUMEN
We aimed to automate Gram-stain analysis to speed up the detection of bacterial strains in patients suffering from infections. We performed comparative analyses of visual transformers (VT) using various configurations including model size (small vs. large), training epochs (1 vs. 100), and quantization schemes (tensor- or channel-wise) using float32 or int8 on publicly available (DIBaS, n = 660) and locally compiled (n = 8500) datasets. Six VT models (BEiT, DeiT, MobileViT, PoolFormer, Swin and ViT) were evaluated and compared to two convolutional neural networks (CNN), ResNet and ConvNeXT. The overall overview of performances including accuracy, inference time and model size was also visualized. Frames per second (FPS) of small models consistently surpassed their large counterparts by a factor of 1-2×. DeiT small was the fastest VT in int8 configuration (6.0 FPS). In conclusion, VTs consistently outperformed CNNs for Gram-stain classification in most settings even on smaller datasets.
RESUMEN
Viral pneumonia is frequently complicated by bacterial co- or superinfection (c/s) with adverse effects on patients' outcomes. However, the incidence of c/s and its impact on the outcomes of patients might be dependent on the type of viral pneumonia. We performed a retrospective observational study in patients with confirmed COVID-19 pneumonia (CP) or influenza pneumonia (IP) from 01/2009 to 04/2022, investigating the incidence of c/s using a competing risk model and its impact on mortality in these patients in a tertiary referral center using multivariate logistic regressions. Co-infection was defined as pulmonary pathogenic bacteria confirmed in tracheal aspirate or bronchoalveolar lavage within 48 h after hospitalization. Superinfection was defined as pulmonary pathogenic bacteria detected in tracheal aspirate or bronchoalveolar lavage 48 h after hospitalization. We examined 114 patients with CP and 76 patients with IP. Pulmonary bacterial co-infection was detected in 15 (13.2%), and superinfection was detected in 50 (43.9%) of CP patients. A total of 5 (6.6%) co-infections (p = 0.2269) and 28 (36.8%) superinfections (p = 0.3687) were detected in IP patients. The overall incidence of c/s did not differ between CP and IP patients, and c/s was not an independent predictor for mortality in a study cohort with a high disease severity. We found a significantly higher probability of superinfection for patients with CP compared to patients with IP (p = 0.0017).
RESUMEN
Toll-like receptor signaling requires functional Toll/interleukin-1 (IL-1) receptor (TIR) domains to activate innate immunity. By producing TIR homologous proteins, microbes inhibit host response induction and improve their own survival. The TIR homologous protein TcpC was recently identified as a virulence factor in uropathogenic Escherichia coli (E. coli), suppressing innate immunity by binding to MyD88. This study examined how the host MyD88 genotype modifies the in vivo effects of TcpC and whether additional, TIR-domain containing proteins might be targeted by TcpC. In wild type mice (wt), TcpC enhanced bacterial virulence, increased acute mortality, bacterial persistence and tissue damage after infection with E. coli CFT073 (TcpC+), compared to a ΔTcpC deletion mutant. These effects were attenuated in Myd88(-/-) and Tlr4(-/-) mice. Transcriptomic analysis confirmed that TcpC inhibits MYD88 dependent gene expression in CFT073 infected human uroepithelial cells but in addition the inhibitory effect included targets in the TRIF and IL-6/IL-1 signaling pathways, where MYD88 dependent and independent signaling may converge. The effects of TcpC on bacterial persistence were attenuated in Trif (-/-) or Il-1ß (-/-) mice and innate immune responses to ΔTcpC were increased, confirming that Trif and Il-1ß dependent targets might be involved in vivo, in addition to Myd88. Furthermore, soluble TcpC inhibited Myd88 and Trif dependent TLR signaling in murine macrophages. Our results suggest that TcpC may promote UTI-associated pathology broadly, through inhibition of TIR domain signaling and downstream pathways. Dysregulation of the host response by microbial TcpC thus appears to impair the protective effects of innate immunity, while promoting inflammation and tissue damage.
Asunto(s)
Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/metabolismo , Escherichia coli/patogenicidad , Factor 88 de Diferenciación Mieloide/fisiología , Receptores de Interleucina-1/metabolismo , Transducción de Señal , Receptores Toll-Like/metabolismo , Factores de Virulencia/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/fisiología , Animales , Biomarcadores/metabolismo , Western Blotting , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Células Epiteliales/microbiología , Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Femenino , Perfilación de la Expresión Génica , Humanos , Inmunidad Innata , Técnicas para Inmunoenzimas , Interleucina-1beta/fisiología , Neoplasias Renales/inmunología , Neoplasias Renales/metabolismo , Neoplasias Renales/microbiología , Macrófagos/citología , Macrófagos/metabolismo , Macrófagos/microbiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Análisis de Secuencia por Matrices de Oligonucleótidos , Estructura Terciaria de Proteína , ARN Mensajero/genética , Receptores de Interleucina-1/antagonistas & inhibidores , Receptores de Interleucina-1/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptor Toll-Like 4/fisiología , Receptores Toll-Like/antagonistas & inhibidores , Receptores Toll-Like/genética , Virulencia/genética , Factores de Virulencia/genéticaRESUMEN
During the ongoing COVID-19 pandemic, PCR testing and antigen tests have proven critical for helping to stem the spread of its causative agent, SARS-CoV-2. However, these methods suffer from either general applicability and/or sensitivity. Moreover, the emergence of variant strains creates the need for flexibility to correctly and efficiently diagnose the presence of substrains. To address these needs we developed the diagnostic test ADESSO (Accurate Detection of Evolving SARS-CoV-2 through SHERLOCK (Specific High Sensitivity Enzymatic Reporter UnLOCKing) Optimization) which employs Cas13 to diagnose patients in 1 h without sophisticated equipment. Using an extensive panel of clinical samples, we demonstrate that ADESSO correctly identifies infected individuals at a sensitivity and specificity comparable to RT-qPCR on extracted RNA and higher than antigen tests for unextracted samples. Altogether, ADESSO is a fast, sensitive and cheap method that can be applied in a point of care setting to diagnose COVID-19 and can be quickly adjusted to detect new variants.