Healthcare-associated outbreak of meticillin-resistant Staphylococcus aureus bacteraemia: role of a cryptic variant of an epidemic clone

BACKGROUND New strains of meticillin-resistant Staphylococcus aureus (MRSA) may be associated with changes in rates of disease or clinical presentation. Conventional typing techniques may not detect new clonal variants that underlie changes in epidemiology or clinical phenotype. AIM To investigate the role of clonal variants of MRSA in an outbreak of MRSA bacteraemia at a hospital in England. METHODS Bacteraemia isolates of the major UK lineages (EMRSA-15 and -16) from before and after the outbreak were analysed by whole-genome sequencing in the context of epidemiological and clinical data. For comparison, EMRSA-15 and -16 isolates from another hospital in England were sequenced. A clonal variant of EMRSA-16 was identified at the outbreak hospital and a molecular signature test designed to distinguish variant isolates among further EMRSA-16 strains. FINDINGS By whole-genome sequencing, EMRSA-16 isolates during the outbreak showed strikingly low genetic diversity (P < 1 × 10(-6), Monte Carlo test), compared with EMRSA-15 and EMRSA-16 isolates from before the outbreak or the comparator hospital, demonstrating the emergence of a clonal variant. The variant was indistinguishable from the ancestral strain by conventional typing. This clonal variant accounted for 64/72 (89%) of EMRSA-16 bacteraemia isolates at the outbreak hospital from 2006. CONCLUSIONS Evolutionary changes in epidemic MRSA strains not detected by conventional typing may be associated with changes in disease epidemiology. Rapid and affordable technologies for whole-genome sequencing are becoming available with the potential to identify and track the emergence of variants of highly clonal organisms

Prevalence of HIV and disease outcomes on the medical and surgical wards at Kamuzu Central Hospital, Lilongwe, Malawi

Introduction: The World Health Organization (WHO) recommends HIV Counseling and Testing (HCT) in a range of clinical settings. We describe the characteristics of patients diagnosed with HIV on the medical and surgical wards at a tertiary care hospital in Malawi. Methods: Under the universal opt-out HCT protocol we characterized the number of new HIV/AIDS infections and associated clinical features among hospitalized surgical and medical patients diagnosed during the course of admission. Results: All 2985 and 3959 medical and surgical patients, respectively, admitted between April 2012 and January 2013 were screened for HCT. 62% and 89% of medical and surgical patients, respectively, had an unknown status on admission and qualified for testing. Of the patients with an unknown status, a new HIV diagnosis was made in 20% and 7% of medical and surgical patients, respectively. Of the newly diagnosed patients with a CD4 count recorded, 91% and 67% of medical and surgical patients, respectively, had a count less than 350, qualifying for ART by Malawi ART guidelines. Newly HIV-diagnosed medical and surgical patients had an inpatient mortality of 20% and 2%, respectively. Discussion: While newly diagnosed HIV-positive medical patients had high inpatient mortality and higher rates of WHO stage 3 or 4 conditions, surgical patients presented with less advanced HIV, though still meeting ART initiation guidelines. The medical inpatient wards are an obvious choice for implementing voluntary counseling and testing (VCT), but surgical patients present with less advanced disease and starting treatment in this group could result in more years of life gained

Choline and its metabolites are differently associated with cardiometabolic risk factors, history of cardiovascular disease, and MRI-documented cerebrovascular disease in older adults

Background: There is a potential role of choline in cardiovascular and cerebrovascular disease through its involvement in lipid and one-carbon metabolism. Objective: We evaluated the associations of plasma choline and choline-related compounds with cardiometabolic risk factors, history of cardiovascular disease, and cerebrovascular pathology. Design: A cross-sectional subset of the Nutrition, Aging, and Memory in Elders cohort who had undergone MRI of the brain (n = 296; mean ± SD age: 73 ± 8.1 y) was assessed. Plasma concentrations of free choline, betaine, and phosphatidylcholine were measured with the use of liquid-chromatography-stable-isotope dilution-multiple-reaction monitoring-mass spectrometry. A volumetric analysis of MRI was used to determine the cerebrovascular pathology (white-matter hyperintensities and small-and large-vessel infarcts). Multiple linear and logistic regression models were used to examine relations of plasma measures with cardiometabolic risk factors, history of cardiovascular disease, and radiologic evidence of cerebrovascular pathology. Results: Higher concentrations of plasma choline were associated with an unfavorable cardiometabolic risk-factor profile [lower highdensity lipoprotein (HDL) cholesterol, higher total homocysteine, and higher body mass index (BMI)] and greater odds of large-vessel cerebral vascular disease or history of cardiovascular disease but lower odds of small-vessel cerebral vascular disease. Conversely, higher concentrations of plasma betaine were associated with a favorable cardiometabolic risk-factor profile [lower low-density lipoprotein (LDL) cholesterol and triglycerides] and lower odds of diabetes. Higher concentrations of plasma phosphatidylcholine were associated with characteristics of both a favorable cardiometabolic risk-factor profile (higher HDL cholesterol, lower BMI, lower C-reactive protein, lower waist circumference, and lower odds of hypertension and diabetes) and an unfavorable profile (higher LDL cholesterol and triglycerides). Conclusion: Choline and its metabolites have differential associations with cardiometabolic risk factors and subtypes of vascular disease, thereby suggesting differing roles in the pathogenesis of cardiovascular and cerebral large-vessel disease compared with that of small-vessel disease

Association of Light Physical Activity Measured by Accelerometry and Incidence of Coronary Heart Disease and Cardiovascular Disease in Older Women

Importance: To our knowledge, no studies have examined light physical activity (PA) measured by accelerometry and heart disease in older women. Objective: To investigate whether higher levels of light PA were associated with reduced risks of coronary heart disease (CHD) or cardiovascular disease (CVD) in older women. Design, Setting, and Participants: Prospective cohort study of older women from baseline (March 2012 to April 2014) through February 28, 2017, for up to 4.91 years. The setting was community-dwelling participants from the Women's Health Initiative. Participants were ambulatory women with no history of myocardial infarction or stroke. Exposures: Data from accelerometers worn for a requested 7 days were used to measure light PA. Main Outcomes and Measures: Cox proportional hazards regression models estimated hazard ratios (HRs) and 95% CIs for physician-adjudicated CHD and CVD events across light PA quartiles adjusting for possible confounders. Light PA was also analyzed as a continuous variable with and without adjustment for moderate to vigorous PA (MVPA). Results: Among 5861 women (mean [SD] age, 78.5 [6.7] years), 143 CHD events and 570 CVD events were observed. The HRs for CHD in the highest vs lowest quartiles of light PA were 0.42 (95% CI, 0.25-0.70; P for trend <.001) adjusted for age and race/ethnicity and 0.58 (95% CI, 0.34-0.99; P for trend = .004) after additional adjustment for education, current smoking, alcohol consumption, physical functioning, comorbidity, and self-rated health. Corresponding HRs for CVD in the highest vs lowest quartiles of light PA were 0.63 (95% CI, 0.49-0.81; P for trend <.001) and 0.78 (95% CI, 0.60-1.00; P for trend = .004). The HRs for a 1-hour/day increment in light PA after additional adjustment for MVPA were 0.86 (95% CI, 0.73-1.00; P for trend = .05) for CHD and 0.92 (95% CI, 0.85-0.99; P for trend = .03) for CVD. Conclusions and Relevance: The present findings support the conclusion that all movement counts for the prevention of CHD and CVD in older women. Large, pragmatic randomized trials are needed to test whether increasing light PA among older women reduces cardiovascular risk

Reinforcing medical authority: clinical ethics consultation and the resolution of conflicts in treatment decisions

Despite substantial efforts in the past 15 years to professionalise the field of clinical ethics consultation, sociologists have not re‐examined past hypotheses about the role of such services in medical decision‐making and their effect on physician authority. In relation to those hypotheses, we explore two questions: (i) What kinds of issues does ethics consultation resolve? and (ii) what is the nature of the resolution afforded by these consults? We examined ethics consultation records created between 2011 and mid‐2015 at a large tertiary care US hospital and found that in most cases, the problems addressed are not novel ethical dilemmas as classically conceived, but are instead disagreements between clinicians and patients or their surrogates about treatment. The resolution offered by a typical ethics consultation involves strategies to improve communication rather than the parsing of ethical obligations. In cases where disagreements persist, the proposed solution is most often based on technical clinical judgements, reinforcing the role of physician authority in patient care and the ethical decisions made about that care.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154312/1/shil13003.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154312/2/shil13003_am.pd

A High Statistics Search for Ultra-High Energy Gamma-Ray Emission from Cygnus X-3 and Hercules X-1

We have carried out a high statistics (2 Billion events) search for ultra-high energy gamma-ray emission from the X-ray binary sources Cygnus X-3 and Hercules X-1. Using data taken with the CASA-MIA detector over a five year period (1990-1995), we find no evidence for steady emission from either source at energies above 115 TeV. The derived upper limits on such emission are more than two orders of magnitude lower than earlier claimed detections. We also find no evidence for neutral particle or gamma-ray emission from either source on time scales of one day and 0.5 hr. For Cygnus X-3, there is no evidence for emission correlated with the 4.8 hr X-ray periodicity or with the occurrence of large radio flares. Unless one postulates that these sources were very active earlier and are now dormant, the limits presented here put into question the earlier results, and highlight the difficulties that possible future experiments will have in detecting gamma-ray signals at ultra-high energies.Comment: 26 LaTeX pages, 16 PostScript figures, uses psfig.sty to be published in Physical Review

Accelerometer-Measured Moderate to Vigorous Physical Activity and Incidence Rates of Falls in Older Women

Objectives: To examine whether moderate to vigorous physical activity (MVPA) measured using accelerometry is associated with incident falls and whether associations differ according to physical function or history of falls. Design: Prospective study with baseline data collection from 2012 to 2014 and 1 year of follow-up. Setting: Women's Health Initiative participants living in the United States. Participants: Ambulatory women aged 63 to 99 (N = 5,545). Measurements: Minutes of MVPA per day measured using an accelerometer, functional status measured using the Short Physical Performance Battery (SPPB), fall risk factors assessed using a questionnaire, fall injuries assessed in a telephone interview, incident falls ascertained from fall calendars. Results: Incident rate ratios (IRRs) revealed greater fall risk in women in the lowest quartile of MVPA compared to those in the highest (IRR = 1.18, 95% confidence interval = 1.01–1.38), adjusted for age, race and ethnicity, and fall risk factors. Fall rates were not significantly associated with MVPA in women with high SPPB scores (9–12) or one or fewer falls in the previous year, but in women with low SPPB scores (≤ 8) or a history of frequent falls, fall rates were higher in women with lower MVPA levels than in those with higher levels (interaction P <.03 and <.001, respectively). Falls in women with MVPA above the median were less likely to involve injuries requiring medical treatment (9.9%) than falls in women with lower MVPA levels (13.0%) (P <.001). Conclusion: These findings indicate that falls are not more common or injurious in older women who engage in higher levels of MVPA. These findings support encouraging women to engage in the amounts and types of MVPA that they prefer. Older women with low physical function or frequent falls with low levels of MVPA are a high-risk group for whom vigilance about falls prevention is warranted

Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events

The $B^0$-$\bar B^0$ oscillation frequency has been measured with a sample of 23 million \B\bar B pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we select events in which both B mesons decay semileptonically and use the charge of the leptons to identify the flavor of each B meson. A simultaneous fit to the decay time difference distributions for opposite- and same-sign dilepton events gives $\Delta m_d = 0.493 \pm 0.012{(stat)}\pm 0.009{(syst)}$ ps$^{-1}$.Comment: 7 pages, 1 figure, submitted to Physical Review Letter

Negotiating Value: Comparing Human and Animal Fracture Care in Industrial Societies

At the beginning of the twentieth-century, human and veterinary surgeons faced the challenge of a medical marketplace transformed by technology. The socio-economic value ascribed to their patients – people and domestic animals – was changing, reflecting the increasing mechanisation of industry and the decreasing dependence of society upon non-human animals for labour. In human medicine, concern for the economic consequences of fractures “pathologised” any significant level of post-therapeutic disability, a productivist perspective contrary to the traditional corpus of medical values. In contrast, veterinarians adapted to the mechanisation of horse-power by shifting their primary professional interest to companion animals; a type of veterinary patient generally valued for the unique emotional attachment of the owner, and not the productive capacity of the animal. The economic rationalisation of human fracture care and the “sentimental” transformation of veterinary orthopaedic expertise indicates how these specialists utilised increasingly convergent rhetorical arguments to justify the application of innovative fracture care technologies to their humans and animal patients. Keywords: Fracture care, Industrialisation, Veterinary History, Human/animal relation