89 research outputs found
Plasmidic qnrA3 Enhances Escherichia coli Fitness in Absence of Antibiotic Exposure
The widespread presence of plasmid-mediated quinolone resistance determinants, particularly qnr genes, has become a current issue. By protecting DNA-gyrase from quinolones, Qnr proteins confer a low level quinolone resistance that is not sufficient to explain their emergence. Since Qnr proteins were hypothesized to act as DNA-binding protein regulators, qnr genes could have emerged by providing a selective advantage other than antibiotic resistance. We investigated host fitness of Escherichia coli isogenic strains after acquisition of the qnrA3 gene, inserted either alone onto a small plasmid (pBR322), or harbored on a large conjugative native plasmid, pHe96(qnrA3) found in a clinical isolate. The isogenic strains were derived from the susceptible E. coli CFT073, a virulent B2 group strain known to infect bladder and kidneys in a mouse model of pyelonephritis. In vitro experiments included growth analysis by automatic spectrophotometry and flow cytometry, and competitions with CFU enumeration. In vivo experiments included infection with each strain and pairwise competitions in absence of antimicrobial exposure. As controls for our experiments we used mutations known to reduce fitness (rpsL K42N mutation) or to enhance fitness (tetA deletion in pBR322). E. coli CFT073 transformed with pBRAM(PBR322-qnrA3) had significantly higher maximal OD than E. coli CFT073 transformed with pBR322 or pBR322ÎtetA, and in vivo competitions were more often won by the qnrA3 carrying strain (24 victories vs. 9 loss among 42 competitions, pâ=â0.001). In contrast, when pHe96(qnrA3) was introduced by conjugation in E. coli CFT073, it exerted a fitness cost shown by an impaired growth observed in vitro and in vivo and a majority of lost competitions (33/35, p<0.0001). In conclusion, qnrA3 acquisition enhanced bacterial fitness, which may explain qnr emergence and suggests a regulation role of qnr. However, fitness was reduced when qnrA3 was inserted onto multidrug-resistant plasmids and this can slow down its dissemination without antibiotic exposure
Characteristics and outcomes of anti-infective de-escalation during health care-associated intra-abdominal infections
COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study
Background:
The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms.
Methods:
International, prospective observational study of 60â109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms.
Results:
âTypicalâ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (â€â18 years: 69, 48, 23; 85%), older adults (â„â70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each Pâ<â0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country.
Interpretation:
This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men
Pneumopathies postopératoires précoces à Pseudomonas aeruginosa aprÚs chirurgie cardiaque
Le but de notre Ă©tude Ă©tait d Ă©valuer les caractĂ©ristiques des patients dĂ©veloppant une pneumopathie postopĂ©ratoire (PPO) prĂ©coce aprĂšs chirurgie cardiaque (CC), en particulier les PPO Ă Pseudomonas aeruginosa (PA). Il s'agit d'une Ă©tude rĂ©trospective de 2005 Ă 2008, Ă partir d une base de donnĂ©es colligĂ©e de maniĂšre prospective. 82 patients (3,2%) des 2540 patients opĂ©rĂ©s consĂ©cutivement d une CC ont acquis une PPO prĂ©coce, et PA Ă©tait responsable de 26 PPO (31,7%). AprĂšs analyse multivariĂ©e, les facteurs de risque de dĂ©velopper une PPO prĂ©coce Ă PA Ă©taient les patients ayant une bronchopneumopathie chronique obstructive (BPCO) (OR = 7,8; IC Ă 95% : 1,6-37,5; P=0,01), les patients ayant reçu une antibiothĂ©rapie dans les 3 mois prĂ©cĂ©dent la chirurgie (OR = 6,2; IC Ă 95% : 1,4-27,2; P=0,02) et les patients ayant un score SOFA >= 10 au moment du diagnostic de PPO (OR = 19.1; IC Ă 95% : 3,8-96,0; P=0,0004). Les patients dĂ©veloppant une PPO Ă PA avaient plus frĂ©quemment une antibiothĂ©rapie probabiliste inadaptĂ©e que les patients dĂ©veloppant une PPO aux autres germes (38,5% contre 7,1%, P=0,0005), et une mortalitĂ© plus Ă©levĂ©e (57,7% vs 25,0%, P=0,004). Cette Ă©tude a montrĂ© que PA pouvait ĂȘtre frĂ©quemment responsable des PPO prĂ©coce (31,7%) aprĂšs CC. L antibiothĂ©rapie empirique Ă©tait frĂ©quemment inadaptĂ©e aprĂšs une PPO Ă PA (38,5%). Ces rĂ©sultats incitent Ă modifier notre antibiothĂ©rapie empirique dans ce contexte et Ă prendre en compte PA dans les PPO prĂ©coces sĂ©vĂšres, chez les patients BPCO et ayant reçu une antibiothĂ©rapie prĂ©alablePARIS6-Bibl.PitiĂ©-SalpĂȘtrie (751132101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
SARS-CoV-2 with Panton-Valentine leukocidin-producing Staphylococcus aureus healthcare-associated pneumonia in the Indian Ocean
At this time, the literature reports only one case of superinfection with Panton-Valentine leukocidin (PVL)-producing Staphylococcus aureus in a patient with severe acute respiratory distress syndrome secondary to coronavirus 2 (SARS-CoV-2) pneumonia. Here we report the first two cases of PVL-producing S. aureus healthcareassociated pneumonia in patients hospitalized for SARS-CoV-2 pneumonia in the Indian Ocean region. The two isolated strains of S. aureus were found to belong to the ST152/t355 clone, a known PVL-producing S. aureus clone that circulates in Africa and is responsible for infections imported into Europe. Our two cases reinforce the hypothesis that SARS-CoV-2 infection favors the occurrence of PVL-producing S. aureus pneumonia. Production of PVL should be searched in patients returning from the Indian Ocean region who present with severe SARS-CoV-2 pneumonia complicated by superinfection with S. aureus even in the case of late onset healthcare-associated pneumonia Dear Editor, Bacterial superinfections in patients with severe acute respiratory distress syndrome secondary to coronavirus 2 (SARS-CoV-2) pneumonia are relatively rare and are often caused by Staphylococcus aureus [1]. At this time, the literature reports only one case of superinfection with Panton-Valentine leukocidin (PVL)-producing S. aureus in a patient with SARS-CoV-2 pneumonia[2]. Here we report the first two cases of PVL-producing S. aureus healthcare-associated pneumonia in patients hospitalized for SARS-CoV-2 pneumonia in the Indian Ocean region
A sequential testing approach for change-point detection on bus door systems
Detecting change-points and anomalies on sequential data is common in various domains such as fraud detection for credit cards, intrusion detection for cyber-security or military surveillance [1]. This study is motivated by the predictive maintenance of pneumatic doors in transit buses. For this purpose, buses are instrumented and data are collected through embedded sensors. Inspired by the CUSUM and GLR approaches, this paper deals with on-line change-point detection on sequential data where each observation consists in a bivariate curve. The system is considered out of control when a change occurs in the curves probability distribution. A specific regression model is used to describe the curves. The unknown parameters of this model are estimated using the maximum likelihood principle. Experimental studies performed on realistic data demonstrate the promising behavior of the proposed method
Severe community-acquired pneumonia in Reunion Island: Epidemiological, clinical, and microbiological characteristics, 2016â2018
No data are available on severe community-acquired pneumonia (CAP) in the French overseas department of Reunion Island. This is unfortunate as the microorganisms responsible for the disease are likely to differ from those in temperate regions due to a tropical climate and proximity to other islands of the Indian Ocean region. The aim of this study was to assess the epidemiological, clinical, prognosis, and microbiological characteristics of patients with severe CAP in Reunion Island. Materials and methods This retrospective study evaluated all patients with CAP aged >18 years and hospitalized in one of the two intensive care units of Reunion Island between 2016 and 2018. Microorganisms were identified by culture from blood and respiratory samples, multiplex polymerase chain reaction from respiratory samples, urinary antigen tests, and serology. Results Over the study period, 573 cases of severe CAP were recorded, with a mean incidence of 22 per 100,000 person-years. The most frequently isolated microorganism was influenza (21.9%) followed by Streptococcus pneumoniae (12%). The influenza virus was detected in affected patients all year round. Twenty-four patients with severe CAP came from another island of the Indian Ocean region (4.2%), mainly Madagascar (>50%). Two of these patients presented with melioidosis and 4 were infected with Acinetobacter spp
Emergence of melioidosis in the Indian Ocean region: Two new cases and a literature review.
Melioidosis is a disease caused by bacteria called B. pseudomallei. Infections can develop after contact with standing water. This disease can reach all the organs and especially the lungs. It is associated with a high mortality rate (up to 50%). Melioidosis is endemic in northern Australia and in Southeast Asia. Nevertheless, B. pseudomallei may be endemic in the Indian Ocean region and in Madagascar in particular, so clinicians and microbiologists should consider acute melioidosis as a differential diagnosis in the Indian Ocean region, in particular from Madagascar
Case Report: Emergence of Candida auris in the Indian Ocean Region
International audienceCandida auris is an emerging multidrug-resistant yeast that can cause severe infections and spread easily between hospitalized patients, leading to outbreaks in hospital. Here, we report the first four cases of colonization and invasive infection with C. auris reported in the Indian Ocean region. All cases were observed in the French overseas Reunion Island, a very popular destination for European travelers. Three patients had urinary tract or skin colonization, and one had a fatal invasive infection. In three cases, including that of the infected patient, the yeast was not initially identified as C. auris , preventing specific hygiene measures to be implemented as suggested in the December 2016 clinical alert to European healthcare facilities. The infected patient likely acquired C. auris in the intensive care unit from the first colonized patient. This is the first case of C. auris infection and the first potential case of nosocomial transmission of the pathogen to be reported in the French overseas Reunion Island
Determinants and prognosis of high-sensitivity cardiac troponin T peak plasma concentration in patients hospitalized for non-cardiogenic shock
Purpose: The aim of this study was to assess the determinants and prognostic value of high-sensitivity cardiac troponin T peak plasma concentration in intensive care unit patients with non-cardiogenic shock. Material and methods: A prospective observational cohort study was conducted in a single intensive care unit between November 2014 and December 2015. Results: During the study period, 206 patients were hospitalized in the intensive care unit for non-cardiogenic shock and the median peak high-sensitivity cardiac troponin T was 55.1 [24.5â136]âpg/mL. A multivariate analysis combining all variables showed that higher body mass index ( t â=â2.52, Pâ =â0.01), lower left ventricular systolic function ( t â=ââ2.73, Pâ =â0.007), higher white blood cell count ( t â=â3.72, Pâ =â0.0001), lower creatinine clearance ( t â=ââ2.84, Pâ =â0.0005), higher lactate level ( t â=â2.62, Pâ =â0.01) and ST-segment depression ( t â=â3.98, Pâ =â0.0001) best correlated with log 10 -transformed high-sensitivity cardiac troponin T peak plasma concentration. After multivariate analysis, the high-sensitivity cardiac troponin T peak was not associated with a significant reduction of in-hospital mortality (adjusted odds ratioâ=â0.99 (95% confidence interval: 0.93â1.02)). Conclusion: High-sensitivity cardiac troponin T elevation was very common in patients hospitalized for non-cardiogenic shock. The factors significantly associated with high-sensitivity cardiac troponin T peak plasma concentration were higher body mass index, decreased left ventricular systolic ejection fraction, higher leucocyte count, decreased renal function, increased lactate level, and ST-segment depression. The high-sensitivity cardiac troponin T peak was not significantly associated with in-hospital mortality in this setting
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