Point-Counterpoint: What is the optimal approach for detection of Clostridium difficile infection?

In 2010, we published an initial point-counterpoint on laboratory diagnosis of C. difficile infection (CDI). At that time, nucleic acid amplification tests (NAATs) were just becoming commercially available, and the idea of algorithmic approaches to CDI was being explored. Now there are numerous NAATs in the marketplace and based on recent proficiency test surveys, they have become the predominant method used for CDI diagnosis in the United States. At the same time, there is a body of literature that suggests that NAATs lack clinical specificity and thus inflate CDI rates. Hospital administrators are taking note of institutional CDI rates because they are publicly reported. They have become an important metric impacting hospital safety ratings and value-based purchasing where hospitals may have millions of dollar of reimbursement at risk. In this point-counterpoint using a Frequently Asked Question approach, Ferric Fang of the University of Washington, who has been a consistent advocate for NAAT-only approach for CDI diagnosis, will discuss the value of a NAAT-only approach, while Christopher Polage of the University of California-Davis and Mark Wilcox of Leeds University, UK, who have each recently written important articles on the value of toxin detection in the diagnosis, will discuss the impact of toxin detection in CDI diagnosis

Examining the Influence of Community Institutions on Inner Ring Suburban Resilience: A Study in Southeastern Pennsylvania

Inner ring suburbs are vulnerable as they face continual downward pressure amidst increasingly complex post-industrial regional dynamics. Many suburban policymakers focus on housing and commercial development when considering ways to improve their localities through the built environment; they often overlook the potential benefits of community-oriented infrastructure -- namely public libraries, neighborhood recreation facilities, and community festivals/events -- as a catalyst for encouraging economic development and neighborhood social capital. This study asks whether inner ring suburbs that offer vibrant community institutions exhibit greater levels of resilience capacity than those with less vibrant community facilities. Across the country government officials target community institutions for service reduction and/or closure in high-profile proposals to balance budgets in a tight economy. In a number of high-profile urban library budget fights, community protestors cite their library's functions as a safe environment for children after school to socialize and study, a place for public internet access and engaging programming, and as the hub of the community. Such accounts offer a glimpse into the value of community institutions in the making of place. Suburbs are competing to gain and maintain their base of residents in a highly mobile and competitive environment. Tiebout (1956) theorizes that this ease of mobility allows people to act as consumers who choose the community package of services/amenities that best meets their budget and preferences. The group of community institutions at the center of this study - public libraries, parks and recreation facilities, and community festivals/events -- are part of a wider architecture of local community infrastructure that composes a community's package of services and amenities. Public schools are an important element of that community infrastructure and the one that is most often considered to add value to suburban localities. Although public schools are unquestionably a vital community institution, this dissertation challenges the narrative that school quality is the prime suburban value-generator by measuring the value to local resilience of school quality against the vibrancy of these other kinds of community institutions that may nurture community life in different ways. This work addresses three main gaps in the literature. Work measuring the value of, and understanding the effects of, community institutions in local places is scant. Studies linking resilience capacity to a place's institutional fabric often overlook public-oriented, taxpayer-funded, place-based facilities in favor of an emphasis on non-profit organizations. A regional approach with a focus on effects in inner ring suburbs is rare. Through a mixed methods approach utilizing exploratory data analysis and qualitative content analysis on the inner ring Pennsylvania suburbs surrounding Philadelphia, this research considers the effects of community institutions on each of three previously identified resilience components: economic strength, socio-demographic appeal, and community connectivity. Results suggest that townships with middling or low school quality may be supporting forms of community institutions other than public schools as a way to increase appeal when the schools alone are not a sufficient draw. Furthermore, townships possibly gain resilience value from promoting community institutions in an active way. Other findings shed new light on people-oriented approaches to inner ring suburban resilience and sustainable regional development that may be gaining relevance in the context of 21st century place dynamics.Geograph

Search for Early Gamma-ray Production in Supernovae Located in a Dense Circumstellar Medium with the Fermi LAT

Supernovae (SNe) exploding in a dense circumstellar medium (CSM) are hypothesized to accelerate cosmic rays in collisionless shocks and emit GeV gamma rays and TeV neutrinos on a time scale of several months. We perform the first systematic search for gamma-ray emission in Fermi LAT data in the energy range from 100 MeV to 300 GeV from the ensemble of 147 SNe Type IIn exploding in dense CSM. We search for a gamma-ray excess at each SNe location in a one year time window. In order to enhance a possible weak signal, we simultaneously study the closest and optically brightest sources of our sample in a joint-likelihood analysis in three different time windows (1 year, 6 months and 3 months). For the most promising source of the sample, SN 2010jl (PTF10aaxf), we repeat the analysis with an extended time window lasting 4.5 years. We do not find a significant excess in gamma rays for any individual source nor for the combined sources and provide model-independent flux upper limits for both cases. In addition, we derive limits on the gamma-ray luminosity and the ratio of gamma-ray-to-optical luminosity ratio as a function of the index of the proton injection spectrum assuming a generic gamma-ray production model. Furthermore, we present detailed flux predictions based on multi-wavelength observations and the corresponding flux upper limit at 95% confidence level (CL) for the source SN 2010jl (PTF10aaxf).Comment: Accepted for publication in ApJ. Corresponding author: A. Franckowiak ([email protected]), updated author list and acknowledgement

Biomarker-based prediction of inflammatory bowel disease-related colorectal cancer: a case–control study

Regular colonoscopic surveillance for detection of dysplasia is recommended in longstanding inflammatory bowel disease (IBD), however, its sensitivity is disputed. Screening accuracy may increase by using a biomarker-based surveillance strategy.A case-control study was performed to determine the prognostic value of DNA ploidy and p53 in IBD-related neoplasia. Cases with IBD-related colorectal cancer (CRC), detected in our surveillance program between 1985-2008, were selected and matched with two controls, for age, gender, disease characteristics, interval of follow-up, PSC, and previous surgery. Biopsies were assessed for DNA ploidy, p53, grade of inflammation and neoplasia. Progression to neoplasia was analyzed with Cox regression analysis, adjusting for potentially confounding variables.Adjusting for age, we found statistically significant Hazard ratios (HR) between development of CRC, and low grade dysplasia (HR5.5; 95%CI 2.6-11.5), abnormal DNA ploidy (DNA index (DI) 1.06-1.34, HR4.7; 95%CI 2.9-7.8 and DI>1.34, HR6.6; 95%CI 3.7-11.7) and p53 immunopositivity (HR3.0; 95%CI 1.9-4.7) over time. When adjusting for all confounders, abnormal DNA ploidy (DI 1.06-1.34, HR4.7; 95%CI 2.7-7.9 and DI>1.34, HR5.0; 95%CI 2.5-10.0) and p53 immunopositivity (HR1.7; 95%CI 1.0-3.1) remained statistically significant predictive of neoplasia. In longstanding IBD, abnormal DNA ploidy and p53 immunopositivity are important risk factors of developing CRC. The yield of surveillance may potentially increase by adding these biomarkers to the routine assessment of biopsies

Motion - Colonoscopic Surveillance is More Cost Effective than Colectomy in Patients with Ulcerative Colitis: Arguments for the Motion

Patients with ulcerative colitis (UC) are at increased risk for colorectal cancer (CRC), especially those with longstanding disease, pancolitis or primary sclerosing cholangitis. The incidence of colitis- associated cancer is increasing, and the mortality rates from CRC are higher in UC patients than in the general population. Case control studies have demonstrated that surveillance colonoscopy reduces the risk of dying from CRC. A well conducted decision analysis found that surveillance colonoscopy decreases cancer-related mortality and increases life expectancy. The results with surveillance programs were almost as good as with prophylactic colectomy. A subsequent cost effectiveness analysis using the same model found that, compared with a policy of no surveillance, colonoscopic surveillance was more effective at preventing death from CRC and was less costly. The best strategy appears to be to perform colonoscopies every three years. The analysis also showed that colectomy should be recommended in patients with low-grade dysplasia. Patients at very high risk for CRC should undergo yearly colonoscopy, and patients who are concerned about the limitations of this technique should be offered prophylactic colectomy

Low Body Mass Index Can Identify Majority of Osteoporotic Inflammatory Bowel Disease Patients Missed by Current Guidelines

Background. Patients with inflammatory bowel disease (IBD) are at high risk of developing osteoporosis. Our objective was to determine the usefulness of IBD guidelines in identifying patients at risk for developing osteoporosis. Methods. We utilized institutional repository to identify patients seen in IBD center and extracted data on demographics, disease history, conventional, and nonconventional risk factors for osteoporosis and Dual Energy X-ray Absorptiometry (DXA) findings. Results. 59% of patients (1004/1703) in our IBD cohort had at least one risk factor for osteoporosis screening. DXA was documented in 263 patients with indication of screening (provider adherence, 26.2%), and of these, 196 patients had DXA completed (“at-risk” group). Ninety-five patients not meeting guidelines-based risk factors also had DXA completed (“not at-risk” group). 139 (70.9%) patients in “at-risk” group had low BMD, while 51 (53.7%) of “not-at-risk” patients had low BMD. Majority of the patients with osteoporosis (83.3%) missed by the current guidelines had low BMI. Multivariate logistic regression analysis showed that low BMI was the strongest risk factor for osteoporosis (OR 3.07; 95% CI, 1.47–6.42; P = 0.003). Conclusions. Provider adherence to current guidelines is suboptimal. Low BMI can identify majority of the patients with osteoporosis that are missed by current guidelines

Duodenal carcinoma at the ligament of Treitz. A molecular and clinical perspective

Background There is very small occurrence of adenocarcinoma in the small bowel. We present a case of primary duodenal adenocarcinoma and discuss the findings of the case diagnostic modalities, current knowledge on the molecular biology behind small bowel neoplasms and treatment options. Case The patient had a history of iron deficiency anemia and occult bleeding with extensive workup consisting of upper endoscopy, colonoscopy, capsule endoscopy, upper gastrointestinal series with small bowel follow through and push enteroscopy. Due to persistent abdominal pain and iron deficiency anemia the patient underwent push enteroscopy which revealed adenocarcinoma of the duodenum. The patient underwent en-bloc duodenectomy which revealed T3N1M0 adenocarcinoma of the 4th portion of the duodenum. Conclusions Primary duodenal carcinoma, although rare should be considered in the differential diagnosis of occult gastrointestinal bleeding when evaluation of the lower and upper GI tract is unremarkable. We discuss the current evaluation and management of this small bowel neoplasm