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51.
Recently, three epidemics in Dutch hospitals were caused by vancomycin-resistant enterococci (VRE). Although the number of infections was small, spread of colonization was extensive and many infection control measures were necessary to prevent further spread. VRE are relatively avirulent bacteria. However, few, if any, antibiotics are available for treatment of infections caused by VRE and the genetic code for resistance may be transferable to other, more virulent, bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA). Although colonization and infection with MRSA have become endemic in many surrounding countries, such a situation has been prevented in the Netherlands by employing an aggressive 'search and destroy' policy. Although many questions regarding the optimal approach of VRE remain unanswered, a similar policy as employed for MRSA will not be possible. In contrast to MRSA, colonization with VRE occurs in the open population, no populations with increased risk for colonization appear to be definable and colonization cannot be eradicated. Based on common sense, a differentiated approach seems indicated in which extensive infection control measures should only be implemented when spread of a single genotype has been demonstrated. A reference laboratory should be created for uniform genotyping.  相似文献   
52.
Aspergillus endocarditis in chronic granulomatous disease   总被引:2,自引:0,他引:2  
We report the first case, to our knowledge, of Aspergillus endocarditis in chronic granulomatous disease in a patient who also had an atrial septal defect. A diagnosis was made on culture of the organism from the mass despite extensive prior investigation. The presence of distinctive skin lesions as a diagnostic clue of fungaemia is highlighted. Possible advances in diagnosis by detection of fungal cell wall components and in prophylaxis by use of itraconazole are referred to. We conclude that fungal endocarditis should be considered in this condition, especially in the presence of a structural heart defect.  相似文献   
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We studied the influences of antimicrobial agents on the colonization of the respiratory tract and infection with Enterococcus faecalis in intensive care unit (ICU) patients receiving mechanical respiration for at least 3 days. In a matched-cohort analysis, patients receiving topical antimicrobial prophylaxis (TAP) of the oropharynx and stomach with antimicrobial agents not treating E. faecalis were compared with patients not receiving TAP. Patients were matched with controls on the basis of their duration in the ICU, their use of systemic antibiotics treating and not treating E. faecalis, the administration of TAP, their APACHE II score, and surgical procedures they had undergone. In all, 276 patients were analyzed. The colonization of the oropharynx and/or trachea by E. faecalis at admission was demonstrated for 43 patients (16%). Twenty patients (9%) acquired tracheal colonization and 91 patients (40%) acquired oropharyngeal colonization with E. faecalis. In the matched-cohort analysis, 43 patients receiving TAP were matched in two controls each. TAP patients more frequently acquired tracheal colonization (15 of 43 versus 2 of 86 patients, P < 0.00001) and infections with E. faecalis (6 of 43 versus 1 of 86 patients, P < 0.01). The use of topical antibiotics and treating E. faecalis increased the risk for colonization and infection with E. faecalis.  相似文献   
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A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
57.
Vancomycin-resistant enterococci (VRE) have caused hospital outbreaks worldwide, and the vancomycin-resistance gene (vanA) has crossed genus boundaries to methicillin-resistant Staphylococcus aureus. Spread of VRE, therefore, represents an immediate threat for patient care and creates a reservoir of mobile resistance genes for other, more virulent pathogens. Evolutionary genetics, population structure, and geographic distribution of 411 VRE and vancomycin-susceptible Enterococcus faecium isolates, recovered from human and nonhuman sources and community and hospital reservoirs in 5 continents, identified a genetic lineage of E. faecium (complex-17) that has spread globally. This lineage is characterized by 1) ampicillin resistance, 2) a pathogenicity island, and 3) an association with hospital outbreaks. Complex-17 is an example of cumulative evolutionary processes that improved the relative fitness of bacteria in hospital environments. Preventing further spread of this epidemic E. faecium subpopulation is critical, and efforts should focus on the early disclosure of ampicillin-resistant complex-17 strains.  相似文献   
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Finn  EJ; Di Chiro  G; Brooks  RA; Sato  S 《Radiology》1985,156(1):139-141
A number of surgical clips and other metallic materials embedded within patients have ferromagnetic properties that present a potential hazard when in the strong fields associated with magnetic resonance imaging. Several types of magnetometers and metal detectors were investigated as possible pre-imaging screening devices. The sensitivities and costs of these devices are given.  相似文献   
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