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BACKGROUND: Ventilator-associated pneumonia is the leading nosocomial infection in critically ill patients. The frequency of ventilator-associated pneumonia caused by multidrug-resistant bacteria has increased in recent years, and these pathogens cause most of the deaths attributable to pneumonia. The authors, therefore, evaluated factors associated with selected multidrug-resistant ventilator-associated pneumonia in critical care patients. METHODS: The authors prospectively recorded potential risk factors at the time of intensive care unit admission. An endotracheal aspirate was obtained in all patients who met clinical criteria for pneumonia. Patients were considered to have ventilator-associated pneumonia only when they met the clinical criteria and aspirate culture was positive for bacteria 48 h or more after initiation of mechanical ventilation. Pediatric patients were excluded. Adult patients with ventilator-associated pneumonia were first grouped as "early-onset" (< 5 days) and "late-onset," determined by episodes of ventilator-associated pneumonia, and then, assigned to four groups based on the bacteria cultured from their tracheal aspirates: Pseudomonas aeruginosa, Acinetobacter baumanii, methicillin-resistant staphylococci, and all others. The first three bacteria were considered to be multidrug resistant, whereas the others were considered to be antibiotic susceptible. Potential risk factors were evaluated with use of univariate statistics and multivariate regression. RESULTS: Among 486 consecutive patients admitted during the study, 260 adults underwent mechanical ventilation for more than 48 h. Eighty-one patients (31%) experienced 99 episodes of ventilator-associated pneumonia, including Pseudomonas(33 episodes), methicillin-resistant staphylococci (17 episodes), Acinetobacter(9 episodes), and nonresistant bacteria (40 episodes). Sixty-six of these episodes were early onset and 33 episodes were late onset. Logistic regression analysis identified three factors significantly associated with early-onset ventilator-associated pneumonia caused by any one of the multidrug-resistant bacterial strains: emergency intubation (odds ratio, 6.4; 95% confidence interval, 2.0-20.2), aspiration (odds ratio, 12.7; 95% confidence interval, 2.4-64.6), and Glasgow coma score of 9 or less (odds ratio, 3.9; 95% confidence interval, 1.3-11.3). A. baumanii-related pneumonia cases were found to be significantly associated with two of these factors: aspiration (odds ratio, 14.2; 95% confidence interval, 1.5-133.8) and Glasgow coma score (odds ratio, 6.0; 95% confidence interval, 1.1-32.6). CONCLUSIONS: The authors recommend that patients undergoing emergency intubation or aspiration or who have a Glasgow coma score of 9 or less be monitored especially closely for early-onset multidrug-resistant pneumonia. The occurrence of aspiration and a Glasgow coma score of 9 or less are especially associated with pneumonia caused by A. baumanii.  相似文献   
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BACKGROUND: This study examines the experience of the Spanish Multicenter Study of Neuroendocrine Tumors of the Lung through the clinical data and behavior of patients treated for this pathologic process. METHODS: From 1980 to 1997, 361 cases of neuroendocrine carcinomas (NEC) were treated surgically. Patients were enrolled in a protocol using the pathologic and follow-up reports. According to Dreslers' criteria, the cases were segregated into grade 1 (typical carcinoid), grade 2 (atypical carcinoid), grade 3 large cell type, and grade 3 small cell type. Several variables were reviewed in all patients. Statistical analysis was performed to determine whether clinical characteristics and differentiation were associated with significant differences in the prognosis. RESULTS: A total of 261 cases of NEC were identified with grade 1, 43 with grade 2, and with grade 3: 22 of large and 35 of small cells. Five-year survival for different grades was as follows: grade 1, 96%; 2, 72%; 3 large cell type, 21%; and 3 small cell type, 14%. When a comparative analysis between typical and atypical carcinoids was performed a significant difference for mean age, tumor size, nodal metastases, and recurrence was observed. However, female sex, nodal metastases, and recurrence rate differed between atypical carcinoids and grade 3 NEC of large cells. A difference in recurrence rate was found between patients with both types of grade 3 NEC. CONCLUSIONS: The progressive deterioration of tumor organization highlights that neuroendocrine tumors constitute a continuous spectrum. A careful observation of pathologic findings is necessary to individualize their prognostic factors.  相似文献   
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INTRODUCTION: Presence of circulating DNA in the serum of patients with cancer makes detection of tumour-specific genetic alterations feasible. OBJECTIVE: To study serum DNA concentration in patients diagnosed as having advanced Non-Small Cell Lung Cancer (NSCLC) and to evaluate its relationship with age, histology, stage, response, time-to-progression (TTP), and survival. METHODS: Serum DNA from 78 patients was purified and spectrophotometrically quantified. RESULTS: No significant correlations were found between serum DNA concentration and age, histology, response and survival. There was a significant correlation with respect to stage (IIIB = 408.75 ng/ml; IV = 478.74 ng/ml; p = 0.02). When patients were grouped according to DNA concentration, significant correlation with TTP was found; establishing a cut-off point at 500 ng/ml ([DNA] < 500 ng/ml TTP = 7.25 months, 95%CI: 3.5-5.25; [DNA ] > or = 500 ng/ml TTP = 4.25 months, 95%CI: 2-6.5; p = 0.05). CONCLUSIONS: Using the present method, DNA concentration quantification appears to be simple, but with certain deficiencies due to inter-sample variability and low specificity. This is because total DNA concentration is measured without distinguishing as to whether it is tumour-related. We suggest that there is a correlation between DNA concentration and prognosis which enables an analysis of the natural history of the disease.  相似文献   
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