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61.
62.
Brucellar meningitis   总被引:5,自引:0,他引:5  
Neurobrucellosis develops in less than 5% of cases of systemic brucellosis; however, most patients with neurobrucellosis have meningeal involvement. Seven new cases of brucellar meningitis and 17 cases from the Spanish- and English-language medical literature are analyzed in terms of epidemiologic data, clinical manifestations, laboratory results for cerebrospinal fluid and serum, treatment, and course of the disease. Brucellar meningitis mimics other neurologic and non-neurologic conditions, and its diagnosis is only suggested in the presence of adequate epidemiologic information. Isolation of Brucella from the cerebrospinal fluid is uncommon. Treatment is accomplished with the combination of tetracycline or doxycycline and streptomycin, rifampin, or both. Mean length of therapy in the seven new cases was 8.5 months. Brucellar meningitis has a better prognosis than other forms of chronic meningitis, and mortality is low for reasons that are not clear; however, the incidence of minor sequelae is high.  相似文献   
63.
The purpose of this study was to determine the prevalence, risk factors, and prognostic value of ocular lesions in unselected patients with bacteremia. A total of 202 bacteremic patients, 101 nonbacteremic septic patients, and 90 nonseptic control patients were compared in a prospective, controlled, observational study. Ocular lesions related to bacteremia were found in 12% of the bacteremic group, 5% of the septic group, and 2% of the control group. Ocular lesions were significantly more frequent in the bacteremic patients than in the control patients (P=.007). The severity of the clinical condition and the presence of fungemia predict independently a higher risk of ocular lesions. Mortality rates among bacteremic patients with and without ocular lesions were, respectively, 32% and 8% (P<.01; OR, 3.99). The asymptomatic nature of most ocular lesions in patients with bloodstream infections and the impossibility of amelioration in most cases lead us to recommend ophthalmologic examination for bacteremic patients only when prognostic information is needed.  相似文献   
64.
OBJECTIVE: To define the incidence, risk factors, and characteristics of bloodstream infections (BSIs) after invasive nonsurgical cardiologic procedures (ICPs). METHODS: Retrospective case-control study; multivariate analysis. RESULTS: Between January 1991 and December 1998, 22 006 ICPs were performed in our hospital and 25 BSIs were documented within 72 hours after ICP. Overall incidence of bacteremia was 0.11% (25 cases) (0.24% after percutaneous transluminal coronary angioplasty [14 cases of 5625 patients], 0.06% [corrected] after diagnostic cardiac catheterization [9 cases of 14 034 patients], and 0.08% [corrected] after electrophysiologic studies [2 cases of 2347 patients]). These 25 patients with bacteremia were compared with 50 controls randomly selected among patients who underwent an ICP but did not have BSIs. Patient-related risk factors for BSI were age older than 60 years (20 cases [80%] vs 28 controls [56%]), valvular disease (4 [16%] vs 1 [2%]), congestive heart failure (7 [28%] vs 1 [2%]), indwelling bladder catheter before the ICP (5 [20%] vs 1 [2%]), more than 1 puncture for the ICP (5 [20%] vs 3 [6%]), a prolonged procedure (83.7 vs 65.1 minutes); and/or more than 1 ICP performed (2 [8%] vs 0). Multivariate analysis identified the presence of congestive heart failure (odds ratio, 21; 95% confidence interval, 6.8-66.0) and age older than 60 years (odds ratio, 1.9; 95% confidence interval, 1.9-6.3) as independent risk factors for BSI after ICP. Bloodstream infection was detected a median of 1.7 days after the procedure. Gram-negative bacteremia accounted for 17 cases (68%) of the BSIs. Among the patients with BSI, the duration of hospital stay was significantly increased (21 vs 6 days). The overall mortality rate was 0.009% for patients who underwent an ICP (8.0% for the 25 patients with bacteremia documented within 72 hours after ICP). CONCLUSIONS: Bloodstream infection should be included among the potential complications of ICP. Elderly patients with recent congestive heart failure episodes constitute a subgroup with a higher risk of postprocedure bacteremia. Therapy with antimicrobial agents against gram-positive and gram-negative bacteremia should be initiated after performing blood cultures in patients with signs suggestive of infection.  相似文献   
65.
This study evaluates matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) capability for the identification of difficult-to-identify microorganisms. A total of 150 bacterial isolates inconclusively identified with conventional phenotypic tests were further assessed by 16S rRNA sequencing and by MALDI-TOF MS following 2 methods: a) a simplified formic acid-based, on-plate extraction and b) performing a tube-based extraction step. Using the simplified method, 29 isolates could not be identified. For the remaining 121 isolates (80.7%), we obtained a reliable identification by MALDI-TOF: in 103 isolates, the identification by 16S rRNA sequencing and MALDI TOF coincided at the species level (68.7% from the total 150 analyzed isolates and 85.1% from the samples with MALDI-TOF result), and in 18 isolates, the identification by both methods coincided at the genus level (12% from the total and 14.9% from the samples with MALDI-TOF results). No discordant results were observed. The performance of the tube-based extraction step allowed the identification at the species level of 6 of the 29 unidentified isolates by the simplified method. In summary, MALDI-TOF can be used for the rapid identification of many bacterial isolates inconclusively identified by conventional methods.  相似文献   
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The study was designed to identify a subset of heart transplant (HT) recipients who could benefit from the administration of targeted antifungal prophylaxis and to evaluate the efficacy of oral itraconazole as the preventive drug. We have analyzed the risk factors for invasive aspergillosis (IA) in our entire population of HT recipients (1988-2002) and also the role of oral itraconazole prophylaxis that was provided to all patients since 1995 [400 mg q.d. of itraconazole oral (PO) for 3-6 months]. There were 24 cases of IA. Our main results indicate that the independent risk factors for IA after heart transplantation are: re-operation (RR 5.8; 95% CI 1.8-18, p=0.002), cytomegalovirus (CMV) disease (RR 5.2; 95% CI 2-13.9, p=0.001), post-transplant hemodialysis (RR 4.9; 95% CI 1.2-18, p=0.02), and the existence of an episode of IA in the HT program 2 months before or after the transplantation date (RR 4.6; 95% CI 1.5-14.4, p=0.007). Itraconazole prophylaxis showed an independent protective value against developing IA (RR 0.2; 95% CI 0.07-0.9, p=0.03) and also determined a significantly prolonged 1-year survival (RR 0.5; 95% CI 0.3-0.8, p=0.01). We believe that antifungal prophylaxis in heart transplant patients should be offered at least to patients with one or more of these predisposing conditions.  相似文献   
69.
Patients with pneumonia treated in the internal medicine department (IMD) are often at risk of healthcare-associated pneumonia (HCAP). The importance of HCAP is controversial. We invited physicians from 72 IMDs to report on all patients with pneumonia hospitalized in their department during 2 weeks (one each in January and June 2010) to compare HCAP with community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP). We analysed 1002 episodes of pneumonia: 58.9% were CAP, 30.6% were HCAP and 10.4% were HAP. A comparison between CAP, HCAP and HAP showed that HCAP patients were older (77, 83 and 80.5 years; p < 0.001), had poorer functional status (Barthel 100, 30 and 65; p < 0.001) and had more risk factors for aspiration pneumonia (18, 50 and 34%; p < 0.001). The frequency of testing to establish an aetiological diagnosis was lower among HCAP patients (87, 72 and 79; p < 0.001), as was adherence to the therapeutic recommendations of guidelines (70, 23 and 56%; p < 0.001). In-hospital mortality increased progressively between CAP, HCAP and HAP (8, 19 and 27%; p < 0.001). Streptococcus pneumoniae was the main pathogen in CAP and HCAP. Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA) caused 17 and 12.3% of HCAP. In patients with a confirmed aetiological diagnosis, the independent risk factors for pneumonia due do difficult-to-treat microorganisms (Enterobacteriaceae, P. aeruginosa or MRSA) were HCAP, chronic obstructive pulmonary diseases and higher Port Severity Index. Our data confirm the importance of maintaining high awareness of HCAP among patients treated in IMDs, because of the different aetiologies, therapy requirements and prognosis of this population.  相似文献   
70.
An exponent was missing in the denominator of the definition of the Henyey-Greenstein phase function. Besides, the normalization constant of the phase function was presented for the three dimensional case only. We give the correct expression in this erratum for the two- and three-dimensional cases. In addition, we correct for a forgotten scalar product operator in Eq. (15). Those corrections do not alter the results or the conclusions of the paper.OCIS codes: (170.3660) Light propagation in tissues, (170.6280) Spectroscopy, fluorescence and luminescence, (170.6920) Time-resolved imagingIn the definition of the Henyey-Greenstein phase function, Eq. (9) in [1], an exponent was missing in the denominator. In addition, the normalization constant was given for the three-dimensional case only. The correct expression for the two- and three-dimensional cases ispx(r,s^,s^'')=1(gx(r))2Pπ[1+(gx(r))22(gx(r))(s^s^'')]γ,(9)where gx(r) (the anisotropy parameter) describes the degree of anisotropy of the scattering, P is a normalization constant equal to 2 or 4 for the two- and three-dimensional cases, respectively. The exponent γ, appearing in the denominator, also depend on the dimensions of the physical domain and is equal to 1 or 3/2 for the two- and the three-dimension cases, respectively.In Eq. (15) of [1] a scalar product operator is missing after the first nabla operator: the correct expression is(Dx)i,i=[1(4i1)μ2i1], i=1lN.(15)The rest of the text remains the same as in the original paper. We checked; these were typographical errors, and do not alter the calculations nor the conclusions of the paper.  相似文献   
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