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861.
BACKGROUND: Bloodstream infection (BSI) is recognized as an important infectious complication of major trauma. However, its occurrence, the risk factors contributing to its development, and its outcomes have not been well described. DESIGN: Cohort with linkage of regional trauma and microbiology databases. PATIENTS: Adult trauma patients with injury severity score (ISS) > or = 12 admitted to a regional trauma centre during a 33-month period. RESULTS: Of 1797 victims of acute trauma identified (median ISS 20; interquartile range [IQR] 16-25), 71 (4%) had 77 episodes of BSI, for an overall rate of 2.9 per 1000 hospital days. BSI in the majority of patients (37 of 72, or 52%) had onsets within the first week of hospitalization; 7 (10%) patients had community-acquired BSI (onset within 2 d). Independently associated with the development of nosocomial BSI were higher ISSs (odds ratio [OR] 1.04, 95% confidence interval [CI] 1.02-1.07); requirement for ICU admission (OR 7.06, CI 3.38-14.75); and burns (OR 5.75, CI 2.16-15.30). Although trauma-related BSI was a predictor of increased in-hospital case fatality (15/71 v. 208/1726; relative risk 1.75, CI 1.10-2.78), it was not an independent predictor of death. CONCLUSION: In our series, 1 in 25 major trauma cases was complicated by BSI. The infection occurred within the first week after injury in over half of our cases. Knowledge of the epidemiology of these infections will be important for planning preventive or early therapeutic efforts.  相似文献   
862.
The pharmacokinetic profiles of azithromycin given as a single-dose regimen (2.0-g extended-release microspheres) were characterized in serum and white blood cells (WBC) and compared with those of a 3-day regimen (a 500-mg immediate-release tablet once daily; total dose, 1.5 g) in an open-label, randomized, parallel-group study of 24 healthy adult subjects. Serial blood samples were collected up to 5 days after the start of dosing for both regimens. Safety assessments were conducted throughout the study. A single 2.0-g dose of azithromycin microspheres achieved significantly higher exposures in serum and WBC during the first 24 h after the start of dosing than a 3-day regimen: an approximately threefold higher area under the curve from time zero to 24 h postdose (AUC(0-24)) and an approximately twofold higher mean peak concentration on day 1. The single-dose regimen provided total azithromycin exposures in serum and WBC similar to those of the 3-day regimen, as evidenced by the similar AUC(0-120) and trough azithromycin concentrations in serum and WBC (mononuclear leukocytes [MNL] and polymorphonuclear leukocytes [PMNL]). For both regimens, the average total azithromycin exposures in MNL and PMNL were approximately 300- and 600-fold higher than those in serum. Azithromycin concentrations in MNL and PMNL remained above 10 microg/ml for at least 5 days after the start of dosing for both regimens. This "front-loading" of the dose on day 1 is safely achieved by the extended-release microsphere formulation, which maximizes the drug exposure at the time when the bacterial burden is likely to be highest.  相似文献   
863.
Cutaneous leishmaniasis is endemic in the Baluchistan province of Pakistan and poses a great risk to non-immune visitors to the area. The wide spectrum of clinical variants of this common disease is at times a diagnostic challenge. A total of 1709 patients with cutaneous leishmaniasis were recorded over a 1-year period. In 37 (2%) patients the lesions were very unusual, and therefore worth reporting. These included acute paronychial, chancriform, annular, palmoplantar, zosteriform and erysipeloid forms. The zosteriform and erysipeloid forms have rarely been reported previously, but to the best of our knowledge, acute paronychial, chancriform, annular and palmoplantar lesions are being reported for the first time. The morphologically unusual lesions may be attributed to an altered host response or involvement of an atypical strain of parasite in these lesions.  相似文献   
864.
865.
Egypt is one of the countries with very high rates of hepatitis C virus (HCV) related morbidity and mortality. However, little is known about geographical and clinical differences in genetic variability of HCV in Egypt. Using direct sequencing and phylogenetic analysis of partial core/E1 and NS5B regions of the HCV genome, HCV genotype/subtype was determined in 129 HCV‐infected patients residing in three governates in south Egypt: Assuit, Sohag, and Qena. According to clinical stage of infection, patients were categorized into four groups: asymptomatic carriers, n = 16; chronic hepatitis C patients, n = 36; liver cirrhosis, n = 54; and hepatocellular carcinoma (HCC), n = 23. Genotype 4a was detected in 80.6%, whereas 1g, 4l, 4n, 4o, 4f, and 4m were identified in 7.7%, 4.7%, 3.9%, 1.6%, 0.8%, and 0.8% of cases, respectively. The prevalence of 4a differed regionally; from 88.5% (in Sohag) to 64% (in Assuit, P = 0.002). Genotypes 4l and 4n had a higher prevalence in Assuit (12.8%, 10.3%) than Sohag (0%, 0%; P ≤ 0.011). Difference in clinical features of determined genotypes/subtypes was observed; more carriers of non‐4a variants (4l and 4n, 4f, or 4m) had chronic hepatitis compared to carriers of 4a (53.3% vs. 23.1%, P = 0.025), while more patients with 4a had liver cirrhosis (45.2% vs. 13.3%, P = 0.023). Two HCV‐4o strains were isolated in this study, both from patients with HCC. In conclusion, geographical diversity of HCV was revealed in this study in southern Egypt. A further case–control study is required to confirm the trends of differential pathogenicity of HCV subtypes, indicated by this study. J. Med. Virol. 81:1015–1023, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
866.
OBJECTIVES: The aim of this study was to evaluate the association between valvular heart disease (VHD) and maternal and fetal outcome in a relatively large group of patients by a comparison to a well-matched control group. BACKGROUND: Available information regarding outcome of pregnancy in women with VHD is limited to either anecdotal reports or small series of patients without an appropriate control. A better understanding of the effects of valvular abnormalities on pregnancy outcome is of value for risk assessment and the design of a therapeutic plan. METHODS: A retrospective evaluation was made of 66 pregnancies in 64 women with VHD cared for at a tertian-care center with a high-risk obstetrics/cardiology clinic and 66 individually selected normal pregnant women matched in age, ethnicity, obstetrical and medical history, time of initial prenatal care, and year of pregnancy. RESULTS: Women with VHD had a significantly higher incidence of congestive heart failure (38% vs. 0%; p < 0.00001), arrhvthmias (15% vs. 0%, p = 0.002), initiation or increase of cardiac medications (41% vs. 2%, p < 0.0001), and hospitalizations (35% vs. 2%, p < 0.0001). Mortality, however, occurred in only one patient (2% vs. 0%, p = NS) with aortic stenosis (AS) and coarctation. Moreover, VHD also had an effect on fetal outcome, resulting in an increased preterm delivery (23% vs. 6%, p = 0.03), intrauterine growth retardation (21% vs. 0%, p < 0.0001), and a reduced birth weight (2,897 +/- 838 g vs. 3,366 +/- 515 g, p = 0.0003). Increased maternal morbidity and unfavorable fetal outcome were seen mostly in patients with moderate and severe mitral stenosis (MS) and AS. CONCLUSIONS: Pregnancy in women with MS and AS is associated with marked increase in maternal morbidity and unfavorable effect on fetal outcome, which are related to severity of disease. Despite high maternal morbidity, mortality is rare.  相似文献   
867.

Objectives

To detect systolic dysfunction in heart failure with preserved ejection fraction (HFpEF) patients by using global longitudinal strain (GLS).

Methods

This study included 46 heart failure patients: 24 with heart failure with reduced ejection fraction (HFrEF) and 22 with heart failure with preserved ejection fraction (HFpEF), and 20 patients with similar risk factor but no symptoms or signs of heart failure, matched for age and sex, as controls. All patients were screened by echocardiography. The ejection fraction of left ventricle was measured using Simpson’s method and the GLS of the left ventricle was measured by using two-dimensional speckle tracking.

Results

Left ventricular ejection fraction (LVEF) was 61.90?±?2.94% in the controls, 60.45?±?7.4% in the HFpEF group (p?=?0.421), and 32.75?±?8.45% in the HFrEF group (p?=?0.001). The value of left ventricle (LV) GLS (controls?=???19.74?±?1.12%, HFpEF?=???15.03?±?2.03%, HFrEF?=???10.72?±?1.99%, p?=?0.0001) was significantly impaired in the HFpEF group despite normal LVEF.

Conclusion

There is significant left ventricular systolic impairment detected by GLS despite preserved LVEF.  相似文献   
868.
OBJECTIVE: It is a widely accepted practice that children with anaphylaxis from penicillins should avoid cephalosporins. The purpose of the present study was to determine whether there is evidence in the literature to support this practice. DATA SOURCES: MEDLINE, EMBASE, Toxline, International Pharmaceutical Abstracts and PubMed were used to search the literature published from 1966 to 2001. The Canadian Medical Protective Association, Health Canada and the Boston Collaborative Drug Surveillance Program were also contacted to determine whether there were any unpublished cases of cross-reactivity between penicillins and cephalosporins. DATA EXTRACTION: Cases describing the use of cephalosporins in adults and children with positive penicillin skin tests or anaphylaxis from penicillin were evaluated. Case reports of anaphylaxis from cephalosporins in paediatric patients were identified. DATA SYNTHESIS: There have been five reported cases of serious reactions from cephalosporins in patients with a history of anaphylaxis from penicillins. All cases occurred in adults; three developed anaphylaxis from the older, first-generation cephalosporins, cephalothin and cephaloridine; one developed anaphylaxis from cefamandole; and one developed anaphylaxis from cefaclor. There have been 12 other published reports of anaphylaxis from cephalosporins in adults with a history of penicillin allergy or a positive penicillin skin test, but with no history of anaphylaxis from penicillin. In seven studies, in which a total of 158 patients with positive penicillin skin tests were administered cephalosporins, seven had apparent immunoglobulin E-mediated reactions when they were given a cephalosporin. When the class of cephalosporin was able to be determined, none of the reports of reactions from cephalosporins in patients with allergies to penicillin involved third-generation cephalosporins. There have been 13 case reports of anaphylaxis from cephalosporins in paediatric patients. CONCLUSION: There are no published case reports of anaphylaxis from cephalosporins in children with anaphylaxis from penicillin, and there are only a small number of such reports in adults. Anaphylaxis from cephalosporins appears to be incredibly rare in children. There is minimal evidence in the literature to support the avoidance of cephalosporins in children with anaphylaxis from penicillins.  相似文献   
869.
In this study, 121 Escherichia coli samples isolated from clinical specimens obtained from Pakistan Institute of Medical Science, Islamabad, Pakistan, were analyzed for extended-spectrum β-lactamases (ESBLs) and AmpC β-lactamases using disk-diffusion assay and polymerase chain reaction. Of the isolates, 78 and 43 were identified as ESBL and AmpC producers, respectively. The highest resistance (89%) was observed against cefotaxime, followed by ciprofloxacin (87.6%) and cefepime (87%). Genetic analysis showed the presence of different class A and class C β-lactamase genes, either alone (44.7%) or in combination (53.6%). CTX-M (57.7%) was the most prevalent among class A, followed by TEM (20.3%) and SHV (15.4%). CIT (including LAT-1 to LAT-4, CMY-2 to CMY-7, and BIL-1) and MOX (including MOX-1, MOX-2, CMY-1, and CMY-8 to CMY-11) family-specific plasmid-mediated AmpC β-lactamases were the most prevalent among these isolates. Our study showed that both class A and class C β-lactamases contributed to cephalosporin resistance in the E. coli isolates, thereby limiting therapeutic options. Co-expression of these enzymes may further hinder the identification of ESBLs, which is a critical step for designing a successful treatment for multidrug-resistant E. coli.  相似文献   
870.
Acquired cardiovascular conditions are a leading cause of maternal morbidity and mortality. A growing number of pregnant women have acquired and heritable cardiovascular conditions and cardiovascular risk factors. As the average age of childbearing women increases, the prevalence of acute coronary syndromes, cardiomyopathy, and other cardiovascular complications in pregnancy are also expected to increase. This document, the third of a 5-part series, aims to provide practical guidance on the management of such conditions encompassing pre-conception through acute management and considerations for delivery.  相似文献   
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