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Prospectively collected, contemporary data are lacking on how the features of infective endocarditis (IE) vary according to region. We, therefore, compared IE in Rennes, France and Khon Kaen, Thailand. Fifty-eight patients with confirmed IE were enrolled at each site during 2011 and 2012 using a common protocol. Compared with French patients, Thais had a lower median age (47 versus 70 years old; P < 0.001) and reported more animal contact (86% versus 21%; P < 0.001). There were more zoonotic infections among Thai than France patients (6 and 1 cases; P = 0.017) and fewer staphylococcal infections (4 versus 15 cases; P = 0.011). Underlying rheumatic heart disease was more prevalent in Thai than in French patients (31% and 4%; P = 0.001), whereas prosthetic heart valves were less prevalent (9% and 35%; P = 0.001). Our data strengthen previous observations that IE in the tropics has distinctive demographic characteristics, risk factors, and etiologies and underscore the need for improved prevention and control strategies.  相似文献   
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Recent seroepidemiological studies and examinations of Ixodes ricinus ticks in Europe have demonstrated the presence of an emerging tick-borne infection with Rickettsia helvetica. We conducted a serosurvey in 168 Danish patients seropositive for borreliosis reflecting their exposure to I. ricinus ticks. A total of 21 patients (12.5%) had positive antibody titres to R. helvetica including 4 cases of seroconversion. None of the samples were positive for antibodies to Ehrlichia. We conclude that in humans exposed to I. ricinus ticks in Denmark the risk of acquiring rickettsial infection is for the first time demonstrated. In the same region of Denmark we collected 570 I. ricinus ticks from various sources, and examinations by PCR for Rickettsia were performed. Positive reactions were obtained in 23 ticks (4%), and R. helvetica was identified in all 13 of those for which sequencing was performed.  相似文献   
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Lymph node enlargement is a common medical problem, and in a large number of patients, the causes of lymphadenopathy remain undiagnosed. We report a thorough microbiological analysis of 1,688 lymph node biopsy specimens collected in our bartonellosis reference center. We studied lymph node biopsy samples from patients with suspected regional infectious lymph node enlargement from January 2008 to December 2012. To evaluate a useful strategy for the diagnosis of infectious lymphadenitis, specimens were cultured and subjected to molecular assays. Histologic analysis was done when possible. A total of 642 (38%) biopsy specimens were infected with a bacterial agent, and quantitative PCR (qPCR) was significantly better than 16S rRNA gene PCR (rrs) for the detection of Bartonella henselae (P = 0.05), Mycobacterium tuberculosis (P = 0.05), and Mycobacterium avium (P = 0.007). Molecular assays were significantly better than bacterial cultures for the diagnosis of Francisella tularensis (P = 0.017) but were less effective for detecting M. tuberculosis (P = 0.004) and M. avium (P = 0.001). Histologic analysis was done for 412 lymph nodes, and 20% of these were compatible with an infectious lymphadenitis, whereas a neoplasm was found in 29% of these lymph nodes. M. tuberculosis was detected significantly more in female than in male patients (P = 0.01), and patients with cat scratch disease (CSD) were younger than patients with M. tuberculosis, Tropheryma whipplei, and F. tularensis. Negative rrs PCR does not exclude the diagnosis of infectious lymphadenitis. Histologic analysis of lymph node biopsy specimens is critical, as a diagnosis of infectious lymphadenitis does not preclude other concurrent diseases.  相似文献   
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Objective To analyze the pattern of cell-surface expression of the triggering receptor expressed on myeloid cells (TREM) 1 during septic shock.Design and setting Prospective clinical study in an adult 16-bed medical ICU.Patients and methods 25 septic shock patients, 15 patients with shock of noninfectious origin and 7 healthy volunteers. Arterial blood was drawn within 12 h of admission and subjected to flow cytometry analysis after staining with anti-TREM-1 and anti-CD14 antibodies. Repeated sampling was performed on days 2, 3, 5, 7, and 14 in septic shock patients.Results Monocytic TREM-1 expression was significantly higher in septic shock patients (mean fluorescence intensity 2.3±0.2) than in nonseptic patients (1.0±0.1), and healthy volunteers (1.0±0.1). There was no difference in monocytic TREM-1 expression between nonseptic patients and healthy volunteers or between any of the three groups with respect to TREM-1 expression on neutrophils. The time course of TREM-1 expression on monocytes diverged significantly by day 3 between survivors and ns.Conclusions The specificity of TREM-1 regulation by infection is highlighted. Moreover, surface TREM-1 expression on monocytes may prove useful in allowing the follow-up of septic patients during the course of the diseaseElectronic Supplementary Material Electronic supplementary material to this paper can be obtained by using the Springer Link server located at .  相似文献   
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A chromosomally encoded oxacillinase, OXA-69, was characterized from Acinetobacter baumannii AYE. beta-Lactamase OXA-69 shared 97% amino acid identity with the recently described OXA-51 enzyme of A. baumannii and 62 and 56% amino acid identity with the carbapenem-hydrolyzing oxacillinases OXA-24 and OXA-23, respectively. Biochemical characterization of the purified OXA-69 revealed a narrow-spectrum hydrolysis profile but including, at a low level, imipenem and meropenem. By PCR and sequencing bla(OXA-69)-like genes were identified in all A. baumannii strains tested (n = 12), suggesting that this oxacillinase is naturally occurring in that species.  相似文献   
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OBJECTIVES: To compare mortality rates between dopamine-sensitive (Dopa-S) and dopamine-resistant (Dopa-R) septic shock patients, the latter group defined by a mean arterial pressure <70 mm Hg despite the use of 20 mug/kg/min dopamine. DESIGN: A human, prospective observational, multiple-center, clinical trial. SETTING: Ten intensive care units from ten hospitals. PATIENTS: 110 patients with septic shocks. INTERVENTIONS: Following volume resuscitation, patients were treated by a rapid increase in dopamine infusion from 10 to 20 mug/kg/min. If mean arterial pressure remained <70 mm Hg, dopamine treatment was promptly switched to norepinephrine or epinephrine. MEASUREMENTS AND MAIN RESULTS: Dopamine sensitivity, arterial gas, lactate, and organ system failure scores were measured at admission and after 6, 12, 24, 48, 72, 96, and 120 hrs. The overall 28-day mortality rate was 54% for the entire population under study. In multivariate analysis, independent predictors of death were dopamine resistance (odds ratio, 9.5; 95% confidence interval, 3-25), arterial lactate >3.5 mmol/L (odds ratio, 1.75; 95% confidence interval, 1.06-2.55), and Sepsis-related Organ Failure Assessment score >10 (odds ratio, 1.40; 95% confidence interval, 1.07-2.12). Of the 110 patients studied, 66 were observed to be resistant to dopamine (60%). In the Dopa-S group, the 28-day mortality rate was 16% (seven of 44 patients) compared with 78% (52 of 66 patients) in the Dopa-R group (p = .0006). The capacity of dopamine resistance to predict death was associated with a sensitivity of 84% and a specificity of 74%. At 24 hrs, the association of dopamine resistance to a lactate level >3.5 mmol/L improved the prognostic value (sensitivity, 90%, specificity, 92%). CONCLUSIONS: Dopamine sensitivity is associated with decreased mortality rate. Early recognition of dopamine resistant septic shock could allow for better screening of patients with an ominous prognosis.  相似文献   
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