Performance comparison of the cobas Liat and Cepheid GeneXpert systems for Clostridium difficile detection.

Clostridium difficile infection (CDI) is a high burden and significant cause of healthcare-acquired infectious diarrhea in the United States (US). Timely and accurate diagnosis of CDI enables the rapid initiation of antibiotic therapy and infection control policies to minimize disease transmission. Polymerase chain reaction (PCR) assays have become a preferred modality for diagnosing CDI in the US. The cobas Liat Cdiff PCR test is a novel assay that can be performed on-demand for hospital-based testing with a rapid 20-minute turnaround time from specimen collection to result reporting. We compared the clinical performance of the cobas Liat Cdiff test to the previously introduced Xpert C. difficile/Epi test; both tests are FDA-cleared PCR assays that detect the toxin B (tcdB) gene of C. difficile. Prospectively collected and remnant stool specimens from 310 patients with suspected CDI were obtained for analysis. The cobas Liat Cdiff and Xpert PCR tests showed an overall percent agreement of 97.4% (302/310; 95% CI: 95.0-98.9). Low bacterial burdens of toxigenic C. difficile, indicated by significantly delayed PCR cycle threshold (Ct) values, explained most of the discordance. Positive and negative percent agreement of the cobas Liat Cdiff test compared to the Xpert PCR test were 94.5% (52/55) and 98.0% (250/255), respectively. The clinical performance of the cobas Liat Cdiff test, combined with its simplicity of use and rapid result reporting, provides a reliable option for clinical laboratory use.

Whole brain radiation therapy (WBRT) alone versus WBRT and radiosurgery for the treatment of brain metastases.

BACKGROUND: Historically, whole brain radiation therapy (WBRT) has been the main treatment for brain metastases. Stereotactic radiosurgery (SRS) delivers high-dose focused radiation and is being increasingly utilized to treat brain metastases. The benefit of adding SRS to WBRT is unclear. This is an updated version of the original Cochrane Review published in Issue 9, 2012. OBJECTIVES: To assess the efficacy of WBRT plus SRS versus WBRT alone in the treatment of adults with brain metastases. SEARCH METHODS: For the original review, in 2009 we searched the following electronic databases: CENTRAL, MEDLINE, Embase, and CancerLit in order to identify trials for inclusion in this review. For the first update the searches were updated in May 2012.For this update, in May 2017 we searched CENTRAL, MEDLINE, and Embase in order to identify trials for inclusion in the review. SELECTION CRITERIA: We restricted the review to randomized controlled trials (RCTs) that compared use of WBRT plus SRS versus WBRT alone for upfront treatment of adults with newly diagnosed metastases (single or multiple) in the brain resulting from any primary, extracranial cancer. DATA COLLECTION AND ANALYSIS: We used the generic inverse variance method, random-effects model in Review Manager 5 for the meta-analysis. MAIN RESULTS: We identified three studies and one abstract for inclusion but we could only include two studies, with a total of 358 participants in a meta-analysis. This found no difference in overall survival (OS) between the WBRT plus SRS and WBRT alone groups (hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.65 to 1.02; 2 studies, 358 participants; moderate-quality evidence). For participants with one brain metastasis median survival was significantly longer in the WBRT plus SRS group (6.5 months) versus WBRT group (4.9 months; P = 0.04). Participants in the WBRT plus SRS group had decreased local failure compared to participants who received WBRT alone (HR 0.27, 95% CI 0.14 to 0.52; 2 studies, 129 participants; moderate-quality evidence). Furthermore, we observed an improvement in performance status scores and decrease in steroid use in the WBRT plus SRS group (risk ratio (RR) 0.64 CI 0.42 to 0.97; 1 study, 118 participants; low-quality evidence). Unchanged or improved Karnofsky Performance Scale (KPS) at six months was seen in 43% of participants in the combined therapy group versus only 28% in the WBRT-alone group (RR 0.78 CI 0.61 to 1.00; P value = 0.05; 1 study, 118 participants; low-quality evidence). Overall, risk of bias in the included studies was unclear. AUTHORS' CONCLUSIONS: Since the last version of this review we have identified one new study that met the inclusion criteria. However, due to a lack of data from this study we were not able to include it in a meta-analysis. Given the unclear risk of bias in the included studies, the results of this analysis have to be interpreted with caution. In our analysis of all included participants, SRS plus WBRT did not show a survival benefit over WBRT alone. However, performance status and local control were significantly better in the SRS plus WBRT group. Furthermore, significantly longer OS was reported in the combined treatment group for recursive partitioning analysis (RPA) Class I patients as well as patients with single metastasis. Most of our outcomes of interest were graded as moderate-quality evidence according to the GRADE criteria and the risk of bias in the majority of included studies was mostly unclear.

Equivalent Performance of the Cobas® Cdiff Test for Use on the Cobas® Liat® System and the Cobas® 4800 System.

Clostridium difficile infection is a significant health burden, and innovative solutions are needed to shorten time to diagnosis and improve infection control. We evaluated the performance of the cobas® Cdiff test for use on the cobas® Liat® System (cobas® Liat® Cdiff), a single-sample, on-demand, and automated molecular solution with a 20-min turnaround time. The limit of detection was 45-90 colony-forming units (CFUs)/swab for toxigenic strains that covered the most prevalent toxinotypes, including the hyper-virulent epidemic 027/BI/NAP1 strain. Using 442 prospectively collected clinical stool specimens, we compared the performance of the cobas® Liat® Cdiff to direct culture and to the cobas® Cdiff test on the cobas® 4800 System (cobas® 4800 Cdiff) - a medium-throughput molecular platform. The sensitivity and specificity of the cobas® Liat® Cdiff compared to direct culture were 93.1% and 95.1%, respectively, and this performance did not statistically differ from the cobas® 4800 Cdiff (P < 0.05). Direct correlation of the cobas® Liat® and cobas® 4800 Cdiff tests yielded overall percent agreement of 98.6%. The test performance, automation, and turnaround time of the cobas® Liat® Cdiff enable its use for on-demand and out-of-hours testing as a complement to existing batch testing solutions like the cobas® 4800 Cdiff.

Ectopic Fat Depots and Coronary Artery Calcium in South Asians Compared With Other Racial/Ethnic Groups.

BACKGROUND: South Asians have a low body mass index and high prevalence of cardiovascular disease (CVD) relative to other racial/ethnic groups. Radiographically detected ectopic fat distribution is better associated with CVD than body mass index. We assessed whether differences in ectopic fat depots explained differences in the prevalence/severity of coronary artery calcium (CAC), a predictor of incident CVD events, among South Asians compared with other racial/ethnic groups. METHODS AND RESULTS: We examined the associations of radiographically detected visceral, intermuscular, intrahepatic, and pericardial fat with CAC among adults without baseline CVD. We compared 803 South Asians in the Mediators of Atherosclerosis in South Asians Living in America to 4 racial/ethnic groups in the Multi-Ethnic Study of Atherosclerosis: 2622 whites, 1893 blacks, 1496 Latinos, and 803 Chinese Americans. We adjusted for body mass index and known CVD risk factors. South Asians had the highest intrahepatic fat and lowest pericardial fat volume (PFV). There was a positive graded association between ectopic fat and higher CAC scores in all the groups with the strongest associations observed with PFV. PFV was independently associated with CAC severity in South Asians (P=0.01) and blacks (P=0.05) and borderline in whites (P=0.06). PFV partially explained the higher CAC burden in South Asians compared with blacks, but not the other racial/ethnic groups. CONCLUSIONS: Differences in PFV explain a small fraction of the higher CAC burden in South Asians. Our findings suggest that ectopic fat depots may not explain the elevated CAC risk in South Asians.

Qualitative analysis of programmatic initiatives to text patients with mobile devices in resource-limited health systems.

BACKGROUND: Text messaging is an affordable, ubiquitous, and expanding mobile communication technology. However, safety net health systems in the United States that provide more care to uninsured and low-income patients may face additional financial and infrastructural challenges in utilizing this technology. Formative evaluations of texting implementation experiences are limited. We interviewed safety net health systems piloting texting initiatives to study facilitators and barriers to real-world implementation. METHODS: We conducted telephone interviews with various stakeholders who volunteered from each of the eight California-based safety net systems that received external funding to pilot a texting-based program of their choosing to serve a primary care need. We developed a semi-structured interview guide based partly on the Consolidated Framework for Implementation Research (CFIR), which encompasses several domains: the intervention, individuals involved, contextual factors, and implementation process. We inductively and deductively (using CFIR) coded transcripts, and categorized themes into facilitators and barriers. RESULTS: We performed eight interviews (one interview per pilot site). Five sites had no prior texting experience. Sites applied texting for programs related to medication adherence and monitoring, appointment reminders, care coordination, and health education and promotion. No site texted patient-identifying health information, and most sites manually obtained informed consent from each participating patient. Facilitators of implementation included perceived enthusiasm from patients, staff and management belief that texting is patient-centered, and the early identification of potential barriers through peer collaboration among grantees. Navigating government regulations that protect patient privacy and guide the handling of protected health information emerged as a crucial barrier. A related technical challenge in five sites was the labor-intensive tracking and documenting of texting communications due to an inability to integrate texting platforms with electronic health records. CONCLUSIONS: Despite enthusiasm for the texting programs from the involved individuals and organizations, inadequate data management capabilities and unclear privacy and security regulations for mobile health technology slowed the initial implementation and limited the clinical use of texting in the safety net and scope of pilots. Future implementation work and research should investigate how different texting platform and intervention designs affect efficacy, as well as explore issues that may affect sustainability and the scalability.

Whole brain radiation therapy (WBRT) alone versus WBRT and radiosurgery for the treatment of brain metastases.

BACKGROUND: Historically, whole brain radiation therapy (WBRT) has been the main treatment for brain metastases. Stereotactic radiosurgery (SRS) delivers high-dose focused radiation and is being increasingly utilized to treat brain metastases. The benefit of adding SRS to WBRT is unclear. This is an updated version of the original Cochrane review published in Issue 6, 2010. OBJECTIVES: To assess the efficacy of WBRT plus SRS versus WBRT alone in the treatment of brain metastases. SEARCH METHODS: In the original review we searched the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 2, 2009), MEDLINE (1966 to 2009), EMBASE (1980 to 2009), and CancerLit (1975 to 2009) in order to identify trials for inclusion in this review.In this update we searched the following electronic databases in May 2012: Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 5, 2012), MEDLINE (2009 to May week 4 2012), and EMBASE (2009 to 2012 week 21) in order to identify trials for inclusion in the review. SELECTION CRITERIA: The review was restricted to randomized controlled trials (RCTs) that compared use of WBRT plus SRS versus WBRT alone for upfront treatment of adult patients with newly diagnosed metastases (single or multiple) in the brain resulting from any primary, extracranial cancer. DATA COLLECTION AND ANALYSIS: The Generic Inverse Variance method, random-effects model in RevMan 5 was used for the meta-analysis. MAIN RESULTS: A meta-analysis of two trials with a total of 358 participants, found no statistically significant difference in overall survival (OS) between WBRT plus SRS and WBRT alone groups (hazard ratio (HR) 0.82; 95% confidence interval (CI) 0.65 to 1.02). For patients with one brain metastasis median survival was significantly longer in WBRT plus SRS group (6.5 months) versus WBRT group (4.9 months; P = 0.04). Patients in the WBRT plus SRS group had decreased local failure compared to patients who received WBRT alone (HR 0.27; 95% CI 0.14 to 0.52). Furthermore, a statistically significant improvement in performance status scores and decrease in steroid use was seen in the WBRT plus SRS group. Unchanged or improved Karnofsky Performance Scale (KPS) at 6 months was seen in 43% of patients in the combined therapy group versus only 28% in WBRT group (P = 0.03). Overall, risk of bias in the included studies was unclear. AUTHORS' CONCLUSIONS: Since the last version of this review no new studies were found that met the inclusion criteria. Given the unclear risk of bias in the included studies, the results of this analysis have to be interpreted with caution. Analysis of all included patients, SRS plus WBRT, did not show a survival benefit over WBRT alone. However, performance status and local control were significantly better in the SRS plus WBRT group. Furthermore, significantly longer OS was reported in the combined treatment group for recursive partitioning analysis (RPA) Class I patients as well as patients with single metastasis.

Whole brain radiation therapy (WBRT) alone versus WBRT and radiosurgery for the treatment of brain metastases.

BACKGROUND: Historically, whole brain radiation therapy (WBRT) has been the main treatment for brain metastases. Stereotactic radiosurgery (SRS) delivers high dose focused radiation and is being increasingly utilized to treat brain metastases. The benefit of adding radiosurgery to WBRT is unclear. OBJECTIVES: To assess the efficacy of WBRT plus radiosurgery versus WBRT alone in the treatment of of brain metastases. SEARCH STRATEGY: We searched the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 2, 2009), MEDLINE (1966 to 2009), EMBASE (1980 to 2009) and CancerLit (1975 to 2009) in order to identify trials for inclusion in this review. SELECTION CRITERIA: The review was restricted to randomised controlled trials (RCTs) that compared use of radiosurgery and WBRT versus WBRT alone for upfront treatment of adult patients with newly diagnosed metastases (single or multiple) in the brain resulting from any primary, extracranial cancer DATA COLLECTION AND ANALYSIS: The Generic Inverse Variance method, random effects model in RevMan 5 was used for the meta-analysis. MAIN RESULTS: A meta-analysis of two trials with a total of 358 participants, found no statistically significant difference in overall survival (OS) between WBRT plus radiosurgery and WBRT alone groups (HR = 0.82, 95% CI 0.65 to 1.02). For patients with one brain metastasis median survival was significantly longer in WBRT plus SRS group (6.5 months) versus WBRT group (4.9 months, P = 0.04). Patients in the WBRT plus radiosurgery group had decreased local failure compared to patients who received WBRT alone (HR = 0.27, 95% CI 0.14 to 0.52). Furthermore, a statistically significant improvement in performance status scores and decrease in steroid use was seen in the WBRT plus SRS group. Unchanged or improved KPS at 6 months was seen in 43% of patients in the combined therapy group versus only 28% in WBRT group (P = 0.03). Overall, risk of bias in the included studies was unclear. AUTHORS' CONCLUSIONS: Given the unclear risk of bias in the included studies, the results of this analysis have to be interpreted with caution. Analysis of all included patients, SRS plus WBRT, did not show a survival benefit over WBRT alone. However, performance status and local control were significantly better in the SRS plus WBRT group. Furthermore, significantly longer OS was reported in the combined treatment group for RPA Class I patients as well as patients with single metastasis.

Red blood cell docosahexaenoic acid and eicosapentaenoic acid concentrations are positively associated with socioeconomic status in patients with established coronary artery disease: data from the Heart and Soul Study.

Traditional cardiac risk factors only partially explain the biological mechanisms by which persons of lower socioeconomic status (SES) have higher cardiovascular risk. Dietary factors, resulting in lower circulating levels of (n-3) fatty acids, may also contribute to the increased risk of cardiovascular disease (CVD) in patients with low SES. We tested whether low SES is associated with RBC levels of (n-3) fatty acids in patients with coronary heart disease. We performed a cross-sectional analysis of 987 adults with stable coronary artery disease (CAD) recruited from San Francisco area outpatient clinics. Four SES measures (household income, education, occupation, and housing status) were assessed by self-report. RBC fatty acid levels of 2 (n-3) fatty acids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), were measured in venous blood samples from fasting subjects. Participants with lower household income, education, occupation, and housing status had lower RBC levels of (n-3) fatty acids (P < 0.001 for all 4 measures). In multivariable models, household income, education, and occupation remained strongly associated with DHA and EPA levels after adjustment for demographic factors, BMI, physical activity, statin use, and kidney function (P < 0.001 for all 3 measures). Housing status was not associated with DHA or EPA after multivariable adjustment. Among patients with CAD, 3 indicators of low SES, household income, education, and occupation, were strongly associated with lower RBC levels of (n-3) fatty acids. Our results raise the possibility that (n-3) fatty acids may be an important mediating factor in the association between low SES and CVD.