905 resultados para Tract-infection
Resumo:
Escherichia coli is the primary cause of urinary tract infection (UTI) in the developed world. The major factors associated with virulence of uropathogenic E. coli (UPEC) are fimbrial adhesins, which mediate specific attachment to host receptors and trigger innate host responses. Another group of adhesins is represented by the autotransporter (AT) subgroup of proteins. In this study, we identified a new AT-encoding gene, termed upaH, present in a 6.5-kb unannotated intergenic region in the genome of the prototypic UPEC strain CFT073. Cloning and sequencing of the upaH gene from CFT073 revealed an intact 8.535-kb coding region, contrary to the published genome sequence. The upaH gene was widely distributed among a large collection of UPEC isolates as well as the E. coli Reference (ECOR) strain collection. Bioinformatic analyses suggest β-helix as the predominant structure in the large N-terminal passenger (α) domain and a 12-strand β-barrel for the C-terminal β-domain of UpaH. We demonstrated that UpaH is expressed at the cell surface of CFT073 and promotes biofilm formation. In the mouse UTI model, deletion of the upaH gene in CFT073 and in two other UPEC strains did not significantly affect colonization of the bladder in single-challenge experiments. However, in competitive colonization experiments, CFT073 significantly outcompeted its upaH isogenic mutant strain in urine and the bladder.
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Disulfide bond (DSB) formation is catalyzed by disulfide bond proteins and is critical for the proper folding and functioning of secreted and membrane-associated bacterial proteins. Uropathogenic Escherichia coli (UPEC) strains possess two paralogous disulfide bond systems: the well-characterized DsbAB system and the recently described DsbLI system. In the DsbAB system, the highly oxidizing DsbA protein introduces disulfide bonds into unfolded polypeptides by donating its redox-active disulfide and is in turn reoxidized by DsbB. DsbA has broad substrate specificity and reacts readily with reduced unfolded proteins entering the periplasm. The DsbLI system also comprises a functional redox pair; however, DsbL catalyzes the specific oxidative folding of the large periplasmic enzyme arylsulfate sulfotransferase (ASST). In this study, we characterized the DsbLI system of the prototypic UPEC strain CFT073 and examined the contributions of the DsbAB and DsbLI systems to the production of functional flagella as well as type 1 and P fimbriae. The DsbLI system was able to catalyze disulfide bond formation in several well-defined DsbA targets when provided in trans on a multicopy plasmid. In a mouse urinary tract infection model, the isogenic dsbAB deletion mutant of CFT073 was severely attenuated, while deletion of dsbLI or assT did not affect colonization.
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In asymptomatic bacteriuria (ABU), bacteria colonize the urinary tract without provoking symptoms. Here, we compared the virulence properties of a collection of ABU Escherichia coli strains to cystitis and pyelonephritis strains. Specific urinary tract infection (UTI)-associated virulence genes, hemagglutination characteristics, siderophore production, hemolysis, biofilm formation, and the ability of strains to adhere to and induce cytokine responses in epithelial cells were analyzed. ABU strains were phylogenetically related to strains that cause symptomatic UTI. However, the virulence properties of the ABU strains were variable and dependent on a combination of genotypic and phenotypic factors. Most ABU strains adhered poorly to epithelial cells; however, we also identified a subgroup of strongly adherent strains that were unable to stimulate an epithelial cell IL-6 cytokine response. Poor immune activation may represent one mechanism whereby ABU E. coli evade immune detection after the establishment of bacteriuria.
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Objective: The incidence and cost of complications occurring in older and younger inpatients were compared. Design: Secondary analysis of hospital-recorded diagnosis and costs for multiday-stay inpatients in 68 public hospitals in two Australian states. Main outcome measures: A complication is defined as a hospital-acquired diagnosis that required additional treatment. The Australian Classification of Hospital-Acquired Diagnoses system is used to identify these complications. Results: Inpatients aged >70 years have a 10.9% complication rate, which is not substantially different from the 10.89% complication rate found in patients aged <70 years. Examination of the probability by single years, however, showed that the peak incidence associated with the neonatal period and childbirth is balanced by rates of up to 20% in patients >80 years. Examining the adult patient population (40–70 years), we found that while some common complications are not age specific (electrolyte disorders and cardiac arrhythmias), others (urinary tract and lower respiratory tract infections) are more common in the older adult inpatient. Conclusion: For inpatients aged >70 years, the risks of complications increase. The incidence of hospital-acquired diagnoses in older adults differs significantly from incidence rates found in younger cohorts. Urinary tract infection and alteration to mental state are more common in older adult inpatients. Surprisingly, these complexities do not result in additional costs when compared with costs for the same complications in younger adults. Greater awareness of these differing patterns will allow patient safety efforts for older patients to focus on complications with the highest incidence and cost.
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IgA is an important mucosal antibody that can neutralize mucosal pathogens by either preventing attachment to epithelia (immune exclusion) or alternatively inhibit intraepithelial replication following transcytosis by the polymeric immunoglobulin receptor (pIgR). Chlamydia trachomatis is a major human pathogen that initially targets the endocervical or urethral epithelium in women and men, respectively. As both tissues contain abundant SIgA we assessed the protection afforded by IgA targeting different chlamydial antigens expressed during the extra and intraepithelial stages of infection. We developed an in vitro model utilizing polarizing cells expressing the murine pIgR together with antigen-specific mouse IgA, and an in vivo model utilizing pIgR-/- mice. SIgA targeting the extraepithelial chlamydial antigen, the major outer membrane protein (MOMP), significantly reduced infection in vitro by 24 % and in vivo by 44 %. Conversely, pIgR-mediated delivery of IgA targeting the intraepithelial inclusion membrane protein A (IncA) bound to the inclusion but did not reduce infection in vitro or in vivo. Similarly, intraepithelial IgA targeting the secreted protease Chlamydia protease-like activity factor (CPAF) also failed to reduce infection. Together, these data suggest the importance of pIgR-mediated delivery of IgA targeting extra but not intraepithelial chlamydial antigens for protection against a genital tract infection.
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Introduction. Rett Syndrome is a rare genetic neurodevelopmental disorder usually affecting females. Scoliosis is a common comorbidity and spinal fusion may be recommended if severe. Little is known about long term outcomes. We examined the impact of spinal fusion on survival and risk of severe lower respiratory tract infection (LRTI) in Rett Syndrome. Methods Data were ascertained from hospital medical records, the Australian Rett Syndrome Database, a longitudinal and population-based registry of Rett Syndrome cases established in 1993, and the Australian Institute of Health and Welfare National Death Index database. An extended Cox regression model was used to estimate the effect of spinal surgery on survival in females who developed severe scoliosis (Cobb angle > 45 degrees). Generalized estimating equation modelling was used to estimate the effect of spinal surgery on the odds of developing severe LRTI. Results Severe scoliosis was identified in 140 cases (60.3%) of whom slightly fewer than half (48.6%) developed scoliosis prior to eight years of age. Scoliosis surgery was performed in 98 (69.0%) of those at a median age of 13 years 3 months (IQR 11 years 5 months – 14 years 10 months). After adjusting for mutation type and age of scoliosis onset, the rate of death was lower in the surgery group (HR 0.30, 95% CI 0.12, 0.74, P = 0.009) compared to those without surgery. Rate of death was particularly reduced for those with early onset scoliosis (HR 0.17, 95% CI 0.06, 0.52, P = 0.002). Spinal fusion was not associated with reduction in the occurrence of a severe LRTI overall (OR 0.60, 95%CI 0.27, 1.33, P=0.206) but was associated with a large reduction in odds of severe LRTI among those with early onset scoliosis (OR 0.32, 95%CI 0.11, 0.93, P=0.036). Conclusion With appropriate cautions, spinal fusion confers an advantage to life expectancy in Rett syndrome.
Resumo:
Uropathogenic Escherichia coli (UPEC) are the primary cause of urinary tract infection (UTI) in humans. For the successful colonisation of the human urinary tract, UPEC employ a diverse collection of secreted or surface-exposed virulence factors including toxins, iron acquisition systems and adhesins. In this study, a comparative proteomic approach was utilised to define the UPEC pan and core surface proteome following growth in pooled human urine. Identified proteins were investigated for subcellular origin, prevalence and homology to characterised virulence factors. Fourteen core surface proteins were identified, as well as eleven iron uptake receptor proteins and four distinct fimbrial types, including type 1, P, F1C/S and a previously uncharacterised fimbrial type, designated UCA-like (UCL) fimbriae in this study. These pathogenicity island (PAI)-associated fimbriae are related to UCA fimbriae of Proteus mirabilis, associated with UPEC and exclusively found in members of the E. coli B2 and D phylogroup. We further demonstrated that UCL fimbriae promote significant biofilm formation on abiotic surfaces and mediate specific attachment to exfoliated human uroepithelial cells. Combined, this study has defined the surface proteomic profiles and core surface proteome of UPEC during growth in human urine and identified a new type of fimbriae that may contribute to UTI.
Resumo:
Uropathogenic Escherichia coli (UPEC) are the major cause of urinary tract infections. For successful colonisation of the urinary tract, UPEC employ multiple surface-exposed or secreted virulence factors, including adhesins and iron uptake systems. Whilst individual UPEC strains and their virulence factors have been the focus of extensive research, there have been no outer membrane (OM) proteomic studies based on large clinical UPEC collections, primarily due to limitations of traditional methods. In this study, a high-throughput method based on tandem mass-spectrometry of EDTA heat-induced outer membrane vesicles (OMVs) was developed for the characterisation of the UPEC surface-associated proteome. The method was applied to compare the OM proteome of fifty-four UPEC isolates, resulting in the identification of 8789 proteins, consisting of 619 unique proteins, which were subsequently interrogated for their subcellular origin, prevalence and homology to characterised virulence factors. Multiple distinct virulence-associated proteins were identified, including two novel putative iron uptake proteins, an uncharacterised type of chaperone-usher fimbriae and various highly prevalent hypothetical proteins. Our results give fundamental insight into the physiology of UPEC and provide a framework for understanding the composition of the UPEC OM proteome.
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Urinary tract infections are a major source of morbidity for women and the elderly, with Uropathogenic Escherichia coli (UPEC) being the most prevalent causative pathogen. Studies in recent years have defined a key anti-inflammatory role for Interleukin-10 (IL-10) in urinary tract infection mediated by UPEC and other uropathogens. We investigated the nature of the IL-10-producing interactions between UPEC and host cells by utilising a novel co-culture model that incorporated lymphocytes, mononuclear and uroepithelial cells in histotypic proportions. This co-culture model demonstrated synergistic IL-10 production effects between monocytes and uroepithelial cells following infection with UPEC. Membrane inserts were used to separate the monocyte and uroepithelial cell types during infection and revealed two synergistic IL-10 production effects based on contact-dependent and soluble interactions. Analysis of a comprehensive set of immunologically relevant biomarkers in monocyte-uroepithelial cell co-cultures highlighted that multiple cytokine, chemokine and signalling factors were also produced in a synergistic or antagonistic fashion. These results demonstrate that IL-10 responses to UPEC occur via multiple interactions between several cells types, implying a complex role for infection-related IL-10 during UTI. Development and application of the co-culture model described in this study is thus useful to define the degree of contact dependency of biomarker production to UPEC, and highlights the relevance of histotypic co-cultures in studying complex host-pathogen interactions.
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Aim Scoliosis is a common co-morbidity in Rett syndrome and spinal fusion may be recommended if severe. We investigated the impact of spinal fusion on survival and risk of severe lower respiratory tract infection in Rett syndrome. Method Data were ascertained from hospital medical records, the Australian Rett Syndrome Database, a longitudinal and population-based registry, and from the Australian Institute of Health and Welfare National Death Index database. Cox regression and generalized estimating equation models were used to estimate the effects of spinal surgery on survival and severe respiratory infection respectively in 140 females who developed severe scoliosis (Cobb angle ≥45°) before adulthood. Results After adjusting for mutation type and age of scoliosis onset, the rate of death was lower in the surgery group (hazard ratio [HR] 0.30, 95% confidence interval [CI] 0.12–0.74; p=0.009) compared to those without surgery. Rate of death was particularly reduced for those with early onset scoliosis (HR 0.17, 95% CI 0.06–0.52; p=0.002). There was some evidence to suggest that spinal fusion was associated with a reduction in risk of severe respiratory infection among those with early onset scoliosis (risk ratio 0.41, 95% CI 0.16–1.03; p=0.06). Interpretation With appropriate cautions, spinal fusion confers an advantage to life expectancy in Rett syndrome.
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As infecções do trato urinário (ITUs) são uma das causas mais comuns de consultas médicas. No ambiente hospitalar estão entre as mais frequentes infecções relacionadas à assistência à saúde (35 a 45%). Nos Estados Unidos da América, resultam em 3.600.000 consultas médicas anuais e mais de 100.000 hospitalizações. No Reino Unido, representam 23% das infecções relacionadas à assistência à saúde. Estudos mostram que a E. coli é a bactéria mais isolada em uroculturas (75% a 80%), tanto em pacientes hospitalizados quanto não hospitalizados. A antibioticoterapia para ITU é comumente iniciada empiricamente, antes da urocultura e do antibiograma, por isso, faz-se necessário conhecer a sensibilidade e resistência dos prováveis agentes etiológicos, deve-se considerar o histórico clínico epidemiológico do paciente. No presente estudo foi realizada a análise da resistência das cepas de E. coli isoladas em 261 uroculturas de pacientes assistidos no serviço ambulatorial e hospitalar do Hospital Universitário Pedro Ernesto (HUPE) e, também, de 81 cepas isoladas em uroculturas de pacientes assistidos no serviço ambulatorial de um Hospital Maternidade do Município do Rio de Janeiro (HMMRJ), no período de maio de 2010 a dezembro de 2010. A susceptibilidade aos antimicrobianos foi determinada pela metodologia de disco difusão por Kirby e Bauer. Foram realizadas triagens fenotípicas para cepas produtoras de ESBL e para cepas produtoras de carbapenemases. Através dos dados contidos nos prontuários dos pacientes com uroculturas positivas para E. coli (≥ 105 ufc/mL), foi realizada a pesquisa clínica epidemiológica para se verificar a ocorrência de fatores de risco diversos, para ITU por E. coli. Observou-se que pacientes do sexo feminino são mais susceptíveis a ITU e o uso de antibiótico até 03 meses antes do episódio infeccioso (p= 0,04746), diabetes (p= 0,01683), trauma recente (p= 0,000238), cirurgia abdominal ou pélvica prévia (p= 0,00221), patologia crônica de bexiga (p= 0,002150), uso de cateter urinário (p=0,0002), insuficiência renal crônica (p= 0,02178), e hospitalização por até 06meses prévios (p= 0,01802) podem ser considerados fatores de risco para ITU por E. coli. Verificou-se que o uso de cateter urinário (p=0,000399), cirurgia abdominal ou pélvica prévia (p=0,004458) e o uso de antimicrobianos prévios ao processo infeccioso (p=0,002625), podem ser considerados fatores de risco importantes, para ITU por E. coli multirresistentes. Os pacientes do sexo masculino, apesar de minoria no estudo, representam a maioria dos pacientes com ITU por E. coli multirresistente. Verificou-se que a classe de antimicrobiano utilizado previamente ao episódio infeccioso, aumenta a chance de ocorrer ITU por E. coli multirresistente, principalmente quando associadas ao uso de cateter urinário e cirurgia abdominal ou pélvica prévia. Os perfis de resistência da cepas isoladas dos pacientes assistidos no serviço ambulatorial e hospitalar do HUPE apresentam semelhanças. Apesar do baixo número de cepas multirresistentes entre as isoladas dos pacientes assistidos no serviço ambulatorial do HMMRJ, essas apresentam perfil de resistência semelhante aos perfis das cepas isoladas dos pacientes assistidos no serviço ambulatorial e hospitalar do HUPE. A partir das evidências, percebe-se que o uso racional de antimicrobianos é muito importante para diminuir a problemática da resistência bacteriana
Resumo:
Descrever a prevalência das espécies bacterianas isoladas nas infecções urinárias comunitárias. Descrever os perfis de susceptibilidade aos antibióticos de uso oral utilizado frente às bactérias isoladas nas infecções urinárias comunitárias. Avaliar a prevalência de fenótipos de resistência bacterianos através dos resultados dos testes de susceptibilidade e dos rastreamentos específicos utilizados. Amostras colhidas exclusivamente no atendimento ambulatorial com contagens de unidades formadoras de colônias entre 100.000 a ≥1.000.000 por mililitro (UCF/ml) Com ou sem piúria no exame de elementos anormais na urina e sedimentoscopia (EAS). Foram analisados retrospectivamente os resultados de urinoculturas e dos testes de susceptibilidade a antimicrobianos, realizados em um Laboratório da rede privada na cidade do Rio de janeiro, de pacientes atendidos em ambulatórios e com quadros de ITU. As amostras de urina coletadas englobavam basicamente os seguintes bairros: Botafogo, Barra da Tijuca, Ipanema, Copacabana, Tijuca e Centro. Foram analisados um total de 8.475 culturas de urina divididas em 7.286 urinas de pacientes femininos e 1.189 de pacientes masculinos entre Janeiro de 2006 a Dezembro de 2012. As amostras foram todas coletadas na Cidade do Rio de Janeiro e englobavam basicamente os seguintes bairros: Botafogo, Barra da Tijuca, Ipanema, Copacabana, Tijuca e Centro. Encontramos um percentual de resistência de 27% para ciprofloxacina frente à Escherichia coli que com 68.23% é a principal etiologia encontrada na ITU na comunidade os resultados das três fluoroquinolonas avaliadas no estudo, ciprofloxacina (2 geração), levofloxacina (3 geração) e norfloxacina (2 geração), acharemos respectivamente 27%, 25% e 20% de resistência em Escherichia coli. O uso de fluoroquinolonas em infecções urinárias comunitárias e consequentemente os achados de padrões de resistência neste estudo, reforçam o que já foi descrito em outros trabalhos. A cefalosporina de 2 geração (cefuroxima), demonstrou percentuais de resistência bastante satisfatórios frente as principais etiologias. Em Escherichia coli o percentual foi de 2%, em Klebsiella pneumoniae 3% e em Proteus mirabilis não houve nenhum achado de resistência. Uma das vantagens da cefuroxima é ser ativa quanto à produção de beta lactamase, conferindo um espectro maior frente a possíveis produtoras desta enzima. Seu esquema posológico é de 250mg duas vezes ao dia por 7 dias para infecções urinárias não complicadas. O meio mais eficaz de melhorar a administração antimicrobiana provavelmente envolverá um programa abrangente que incorpora múltiplas estratégias e colaboração entre as diversas especialidades dentro de uma determinada instituição de saúde. Neste contexto, a observação periódica da incidência bacteriana com seus respectivos índices de resistência aos antimicrobianos por sitio de infecção e correlação com os antibióticos mais comumente utilizados, é mandatória para o sucesso terapêutico.
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A invasão de bactérias no trato urinário caracteriza a infecção do sistema urinário. A Escherichia coli é o principal microrganismo associado a esta infecção devido a sua importância em causar ITU, recebeu a denominação de UPEC (Escherichia coli uropatogênica). No presente trabalho pesquisamos em 50 cepas de UPEC, inicialmente isolados de urina de pacientes ambulatoriais com infecções sintomática ou assintomática, a presença de 7 fatores de virulência, através das técnicas de PCR simples e multiplex para verificação dos genes que codificam adesinas P (pap) , fímbria S (sfa), adesina afimbrial (afa), sideroforo (aerobactina- aer), toxinas fator necrotizante citotóxico (cnf) e alfa-hemolisinas (hly), proteína de membrana (traT); ilhas de patogenicidade (virulência) através do marcador PAI. O marcador pCVD432 de EAEC também foi pesquisado nestas amostras. O método difusão em disco foi o utilizado para a determinação dos testes de susceptibilidade aos antimicrobianos. Podemos observar duas faixas etárias de maior incidência de ITU entre as mulheres: 19 a 35 anos, e acima de 50 anos. Sessenta e oito por cento das amostras apresentaram pelo menos um fator de virulência, onde os genes traT (54%) e aer (34%) foram os mais prevalentes. A sequência pCVD432 foi detectado em 6 amostras. No entanto, no ensaio de adesão em células Hep-2, doze amostras não apresentaram aderência (NA 24%). Nas 38 cepas restantes, 24 (48%) apresentaram aderência agregativa (AA). Observamos aderência sem padrão típico (SPT) em 48% das amostras, tendo sido dividido em discreto (SPT-D 22%), moderado (SPT-M 18%) e intenso (SPT-I 8%). Notamos os seguintes perfis de resistência para os antimicrobianos testados: ampicilina (44%), gentamicina (8%), nitrofurantoína (2%), norfloxacino (18%) e sulfametozaxol-trimetoprima (34%).
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BACKGROUND: Enhanced recovery after surgery (ERAS) is a multimodal approach to perioperative care that combines a range of interventions to enable early mobilization and feeding after surgery. We investigated the feasibility, clinical effectiveness, and cost savings of an ERAS program at a major U. S. teaching hospital. METHODS: Data were collected from consecutive patients undergoing open or laparoscopic colorectal surgery during 2 time periods, before and after implementation of an ERAS protocol. Data collected included patient demographics, operative, and perioperative surgical and anesthesia data, need for analgesics, complications, inpatient medical costs, and 30-day readmission rates. RESULTS: There were 99 patients in the traditional care group, and 142 in the ERAS group. The median length of stay (LOS) was 5 days in the ERAS group compared with 7 days in the traditional group (P < 0.001). The reduction in LOS was significant for both open procedures (median 6 vs 7 days, P = 0.01), and laparoscopic procedures (4 vs 6 days, P < 0.0001). ERAS patients had fewer urinary tract infections (13% vs 24%, P = 0.03). Readmission rates were lower in ERAS patients (9.8% vs 20.2%, P = 0.02). DISCUSSION: Implementation of an enhanced recovery protocol for colorectal surgery at a tertiary medical center was associated with a significantly reduced LOS and incidence of urinary tract infection. This is consistent with that of other studies in the literature and suggests that enhanced recovery programs could be implemented successfully and should be considered in U.S. hospitals.
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INTRODUCTION: Bronchiolitis is the most common lower respiratory tract infection in infants, occurring in a seasonal pattern, with highest incidence in the winter in temperate climates and in the rainy season in warmer countries. Bronchiolitis is a common reason for attendance at and admission to hospital.
METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of prophylactic interventions for bronchiolitis in high-risk children? What are the effects of measures to prevent transmission of bronchiolitis in hospital? What are the effects of treatments for children with bronchiolitis? We searched: Medline, Embase, The Cochrane Library, and other important databases up to July 2010 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS: We found 59 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS: In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotics, bronchodilators (oral, inhaled salbutamol, inhaled adrenaline [epinephrine], hypertonic saline), chest physiotherapy, continuous positive airway pressure, corticosteroids, fluid management, heliox, montelukast, nasal decongestants, nursing interventions (cohort segregation, hand washing, gowns, masks, gloves, and goggles), oxygen, respiratory syncytial virus immunoglobulins, pooled immunoglobulins, or palivizumab (monoclonal antibody), ribavirin, or surfactants.