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Since 2004, a total of 131 isolates of Streptococcus pneumoniae multidrug-resistant invasive serotype 8 have been detected in Spain. These isolates showed resistance to erythromycin, clindamycin, tetracycline, and ciprofloxacin. All isolates were obtained from adult patients and shared a common genotype (sequence type [ST]63; penicillin-binding protein 1a [pbp1a], pbp2b, and pbp2x gene profiles; ermB and tetM genes; and a ParC-S79F change). Sixty-eight isolates that required a ciprofloxacin MIC ≥16 μg/mL had additional gyrA gene changes. Serotype 8-ST63 pbp2x sequences were identical with those of antimicrobial drug–susceptible serotype 8-ST53 isolates. Serotype 8-ST63 pbp2b sequences were identical with those of the multidrug-resistant Sweden 15A-ST63 clone. Recombination between the capsular locus and flanking regions of an ST53 isolate (donor) and an ST63 pneumococcus (recipient) generated the novel 15A-ST63 clone. One recombination point was upstream of pbp2x and another was within pbp1a. A serotype 8-ST63 clone was identified as a cause of invasive disease in Spain.  相似文献   
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The group G streptococcus may be a more common human pathogen than previously recognized. A case of group G streptococcal endocarditis is reported and the 11 cases reported previously are reviewed. Group G endocarditis may have significant clinical and prognostic differences from endocarditis caused by the more commonly identified viridans or group D streptococci. Routine serologic grouping of beta-hemolytic streptococcal isolates from serious infections is warranted.  相似文献   
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Present guidelines recommend culturing only central venous catheter (CVC) tips from patients with suspected catheter-related bloodstream infection (CR-BSI). However, a high proportion of these suspicions are not confirmed. Moreover, CVC tip culture increases laboratory workload, and reports of colonization may be meaningless or misleading for the clinician. Our working hypothesis was that CVC tips should be refrigerated and cultured only in patients with positive blood cultures. We evaluated the effect of 6-day refrigeration of 215 CVC tips. We selected all the catheters with a significant count according to the Maki's roll-plate technique and randomly assigned them to 2 groups. In group A, the catheters were recultured after 24 h of refrigeration, and in group B, the catheters were recultured after 6 days more of refrigeration, so that the refrigeration time evaluated would be of 6 days. The yield of refrigerated CVC tips that grow significant colony counts of primary culture in group B was compared with the yield of refrigerated catheter tips in group A. The difference showed that 6-day refrigeration reduced the number of significant CVCs by 15.2%. Only 61 CVCs were obtained from patients with CR-BSI, and in most of them, blood cultures were already positive before CVC culture, so only 0.91% of the CR-BSI episodes would have been misdiagnosed as culture negative after refrigeration. Refrigeration of CVC tips sent for culture and culturing only those from patients with positive blood cultures reduce the workload in the microbiology laboratory without misdiagnosing CR-BSI.  相似文献   
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BACKGROUND: The high degree to which systemic antibiotics are consumed in our country makes a study of those factors determining the spread thereof necessary. Different parameters are involved in the unequal spread of their consumption, including: a) the epidemiology of the infectious processes b) the population-dependent factors and c) factors depending upon the prescribing physicians. This study is aimed at analyzing those determining factors depending upon the population (type of population and age). METHODS: A longitudinal retrospective study based on systemic antibiotic consumption data provided by the company International Marketing Services (IMS) for the January 1, 1996-December 31, 2000 period. The consumption indicator used was the number of daily doses defined per 1000 inhabitants/day (DID). Six geographical areas in the province of Valladolid were placed under study, three of which were urban and the other three mainly rural. RESULTS: The overall consumption by area was as follows: Medina del Campo (25.9DID), the capital city of Valladolid (23.4DID), Laguna de Duero (22.6DID), Northern Area (22.4DID), Southern Area (21.4DID) and, lastly, the Central Area (20.2DID). The specific consumption by areas revealed a greater consumption of amoxicillin in the three urban areas, amoxicillin-clavulanic acid and the major macrolides in Medina del Campo, quinolone antibiotics in the Northern Area and tetracyclines and sulfonamides in the capital city of Valladolid. CONCLUSIONS: Major overall consumption-related differences were found to exist among areas, the maximums being found in the urban areas. These differences were more marked on when studying the geographic spread of the consumption of the main active ingredients.  相似文献   
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The demolition of a maternity building at our institution provided us with the opportunity to study the load of filamentous fungi in the air. External (nearby streets) and internal (within the hospital buildings) air was sampled with an automatic volumetric machine (MAS-100 Air Samplair) at least daily during the week before the demolition, at 10, 30, 60, 90,120, 180, 240, 420, 540 and 660 min post-demolition, daily during the week after the demolition and weekly during weeks 2, 3 and 4 after demolition. Samples were duplicated to analyse reproducibility. Three hundred and forty samples were obtained: 115 external air, 69 'non-protected' internal air and 156 protected internal air [high efficiency particulate air (HEPA) filtered air under positive pressure]. A significant increase in the colony count of filamentous fungi occurred after the demolition. Median colony counts of external air on demolition day were significantly higher than from internal air (70.2 cfu/m(3) vs 35.8 cfu/m(3)) (P < 0.001). Mechanical demolition on day +4 also produced a significant difference between external and internal air (74.5 cfu/m(3) vs 41.7 cfu/m(3)). The counts returned to baseline levels on day +11. Most areas with a protected air supply yielded no colonies before demolition day and remained negative on demolition day. The reproducibility of the count method was good (intra-assay variance: 2.4 cfu/m(3)). No episodes of invasive filamentous mycosis were detected during the three months following the demolition. Demolition work was associated with a significant increase in the fungal colony counts of hospital external and non-protected internal air. Effective protective measures may be taken to avoid the emergence of clinical infections.  相似文献   
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