Systemic Antibiotics for the Treatment of Skin and Soft Tissue Abscesses: A Systematic Review and Meta-Analysis.

STUDY OBJECTIVE: The addition of antibiotics to standard incision and drainage is controversial, with earlier studies demonstrating no significant benefit. However, 2 large, multicenter trials have recently been published that have challenged the previous literature. The goal of this review was to determine whether systemic antibiotics for abscesses after incision and drainage improve cure rates. METHODS: PubMed, the Cumulative Index of Nursing and Allied Health Literature, Scopus, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and bibliographies of selected articles were assessed for all randomized controlled trials comparing adjuvant antibiotics with placebo in the treatment of drained abscesses, with an outcome of treatment failure assessed within 21 days. Data were dual extracted into a predefined worksheet and quality analysis was performed with the Cochrane Risk of Bias tool. RESULTS: Four studies (n=2,406 participants) were identified. There were 89 treatment failures (7.7%) in the antibiotic group and 150 (16.1%) in the placebo group. The calculated risk difference was 7.4% (95% confidence interval [CI] 2.8% to 12.1%), with an odds ratio for clinical cure of 2.32 (95% CI 1.75 to 3.08) in favor of the antibiotic group. There was also a decreased incidence of new lesions in the antibiotic group (risk difference -10.0%, 95% CI -12.8% to -7.2%; odds ratio 0.32, 95% CI 0.23 to 0.44), with a minimally increased risk of minor adverse events (risk difference 4.4%, 95% CI 1.0% to 7.8%; odds ratio 1.29, 95% CI 1.06 to 1.58). CONCLUSION: The use of systemic antibiotics for skin and soft tissue abscesses after incision and drainage resulted in an increased rate of clinical cure. Providers should consider the use of antibiotics while balancing the risk of adverse events.

Assessment of exhaust emissions from carbon nanotube production and particle collection by sampling filters.

UNLABELLED: This study performed a workplace evaluation of emission control using available air sampling filters and characterized the emitted particles captured in filters. Characterized particles were contained in the exhaust gas released from carbon nanotube (CNT) synthesis using chemical vapor deposition (CVD). Emitted nanoparticles were collected on grids to be analyzed using transmission electron microscopy (TEM). CNT clusters in the exhaust gas were collected on filters for investigation. Three types of filters, including Nalgene surfactant-free cellulose acetate (SFCA), Pall A/E glass fiber, and Whatman QMA quartz filters, were evaluated as emission control measures, and particles deposited in the filters were characterized using scanning transmission electron microscopy (STEM) to further understand the nature of particles emitted from this CNT production. STEM analysis for collected particles on filters found that particles deposited on filter fibers had a similar morphology on all three filters, that is, hydrophobic agglomerates forming circular beaded clusters on hydrophilic filter fibers on the collecting side of the filter. CNT agglomerates were found trapped underneath the filter surface. The particle agglomerates consisted mostly of elemental carbon regardless of the shapes. Most particles were trapped in filters and no particles were found in the exhaust downstream from A/E and quartz filters, while a few nanometer-sized and submicrometer-sized individual particles and filament agglomerates were found downstream from the SFCA filter. The number concentration of particles with diameters from 5 nm to 20 µm was measured while collecting particles on grids at the exhaust piping. Total number concentration was reduced from an average of 88,500 to 700 particle/cm(3) for the lowest found for all filters used. Overall, the quartz filter showed the most consistent and highest particle reduction control, and exhaust particles containing nanotubes were successfully collected and trapped inside this filter. IMPLICATIONS: As concern for the toxicity of engineered nanoparticles grows, there is a need to characterize emission from carbon nanotube synthesis processes and to investigate methods to prevent their environmental release. At this time, the particles emitted from synthesis were not well characterized when collected on filters, and limited information was available about filter performance to such emission. This field study used readily available sampling filters to collect nanoparticles from the exhaust gas of a carbon nanotube furnace. New agglomerates were found on filters from such emitted particles, and the performance of using the filters studied was encouraging in terms of capturing emissions from carbon nanotube synthesis.

Clinical predictors for laboratory-confirmed influenza infections: exploring case definitions for influenza-like illness.

OBJECTIVE: To identify clinical signs and symptoms (ie, "terms") that accurately predict laboratory-confirmed influenza cases and thereafter generate and evaluate various influenza-like illness (ILI) case definitions for detecting influenza. A secondary objective explored whether surveillance of data beyond the chief complaint improves the accuracy of predicting influenza. DESIGN: Retrospective, cross-sectional study. SETTING: Large urban academic medical center hospital. PARTICIPANTS: A total of 1,581 emergency department (ED) patients who received a nasopharyngeal swab followed by rRT-PCR testing between August 30, 2009, and January 2, 2010, and between November 28, 2010, and March 26, 2011. METHODS: An electronic surveillance system (GUARDIAN) scanned the entire electronic medical record (EMR) and identified cases containing 29 clinical terms relevant to influenza. Analyses were conducted using logistic regressions, diagnostic odds ratio (DOR), sensitivity, and specificity. RESULTS: The best predictive model for identifying influenza for all ages consisted of cough (DOR=5.87), fever (DOR=4.49), rhinorrhea (DOR=1.98), and myalgias (DOR=1.44). The 3 best case definitions that included combinations of some or all of these 4 symptoms had comparable performance (ie, sensitivity=89%-92% and specificity=38%-44%). For children <5 years of age, the addition of rhinorrhea to the fever and cough case definition achieved a better balance between sensitivity (85%) and specificity (47%). For the fever and cough ILI case definition, using the entire EMR, GUARDIAN identified 37.1% more influenza cases than it did using only the chief complaint data. CONCLUSIONS: A simplified case definition of fever and cough may be suitable for implementation for all ages, while inclusion of rhinorrhea may further improve influenza detection for the 0-4-year-old age group. Finally, ILI surveillance based on the entire EMR is recommended.

Comparing the accuracy of syndrome surveillance systems in detecting influenza-like illness: GUARDIAN vs. RODS vs. electronic medical record reports.

BACKGROUND: A highly sensitive real-time syndrome surveillance system is critical to detect, monitor, and control infectious disease outbreaks, such as influenza. Direct comparisons of diagnostic accuracy of various surveillance systems are scarce. OBJECTIVE: To statistically compare sensitivity and specificity of multiple proprietary and open source syndrome surveillance systems to detect influenza-like illness (ILI). METHODS: A retrospective, cross-sectional study was conducted utilizing data from 1122 patients seen during November 1­7, 2009 in the emergency department of a single urban academic medical center. The study compared the Geographic Utilization of Artificial Intelligence in Real-time for Disease Identification and Alert Notification (GUARDIAN) system to the Complaint Coder (CoCo) of the Real-time Outbreak Detection System (RODS), the Symptom Coder (SyCo) of RODS, and to a standardized report generated via a proprietary electronic medical record (EMR) system. Sensitivity, specificity, and accuracy of each classifier's ability to identify ILI cases were calculated and compared to a manual review by a board-certified emergency physician. Chi-square and McNemar's tests were used to evaluate the statistical difference between the various surveillance systems.ResultsThe performance of GUARDIAN in detecting ILI in terms of sensitivity, specificity, and accuracy, as compared to a physician chart review, was 95.5%, 97.6%, and 97.1%, respectively. The EMR-generated reports were the next best system at identifying disease activity with a sensitivity, specificity, and accuracy of 36.7%, 99.3%, and 83.2%, respectively. RODS (CoCo and SyCo) had similar sensitivity (35.3%) but slightly different specificity (CoCo = 98.9%; SyCo = 99.3%). The GUARDIAN surveillance system with its multiple data sources performed significantly better compared to CoCo (χ2 = 130.6, p < 0.05), SyCo (χ2 = 125.2, p < 0.05), and EMR-based reports (χ2 = 121.3, p < 0.05). In addition, similar significant improvements in the accuracy (>12%) and sensitivity (>47%) were observed for GUARDIAN with only chief complaint data as compared to RODS (CoCo and SyCo) and EMR-based reports. CONCLUSION: In our study population, the GUARDIAN surveillance system, with its ability to utilize multiple data sources from patient encounters and real-time automaticity, demonstrated a more robust performance when compared to standard EMR-based reports and the RODS systems in detecting ILI. More large-scale studies are needed to validate the study findings, and to compare the performance of GUARDIAN in detecting other infectious diseases.

The impact of alternative diagnoses on the utility of influenza-like illness case definition to detect the 2009 H1N1 pandemic.

OBJECTIVE: To investigate the impact of excluding cases with alternative diagnoses on the sensitivity and specificity of the Centers for Disease Control and Prevention's (CDC) influenza-like illness (ILI) case definition in detecting the 2009 H1N1 influenza, using Geographic Utilization of Artificial Intelligence in Real-Time for Disease Identification and Alert Notification, a disease surveillance system. DESIGN: Retrospective cross-sectional study design. SETTING: Emergency department of an urban tertiary care academic medical center. PATIENTS: 1,233 ED cases, which were tested for respiratory viruses from September 5, 2009 to May 5, 2010. MAIN OUTCOME MEASURE: The main outcome measures were positive predictive value, negative predictive value, sensitivity, specificity, and accuracy of the ILI case definition (both including and excluding alternative diagnoses) to detect H1N1. RESULTS: There was a significant decrease in sensitivity (chi2 = 9.09, p < 0.001) and significant improvement in specificity (chi2 = 179, p < 0.001), after excluding cases with alternative diagnoses. CONCLUSION: When early detection of an influenza epidemic is of prime importance, pursuing alternative diagnoses as part of CDC's ILI case definition may not be warranted for public health reporting due to the significant decrease in sensitivity, in addition to the resources required for detecting these alternative diagnoses.

Characterization of exposures to nanoscale particles and fibers during solid core drilling of hybrid carbon nanotube advanced composites.

This work investigated exposures to nanoparticles and nanofibers during solid core drilling of two types of advanced carbon nanotube (CNT)-hybrid composites: (1) reinforced plastic hybrid laminates (alumina fibers and CNT); and (2) graphite-epoxy composites (carbon fibers and CNT). Multiple real-time instruments were used to characterize the size distribution (5.6 nm to 20 microm), number and mass concentration, particle-bound polyaromatic hydrocarbons (b-PAHs), and surface area of airborne particles at the source and breathing zone. Time-integrated samples included grids for electron microscopy characterization of particle morphology and size resolved (2 nm to 20 microm) samples for the quantification of metals. Several new important findings herein include generation of airborne clusters of CNTs not seen during saw-cutting of similar composites, fewer nanofibers and respirable fibers released, similarly high exposures to nanoparticles with less dependence on the composite thickness, and ultrafine (< 5 nm) aerosol originating from thermal degradation of the composite material.

Characterization and evaluation of nanoparticle release during the synthesis of single-walled and multiwalled carbon nanotubes by chemical vapor deposition.

Airborne nanoparticles released during the synthesis of single-walled and multi-walled carbon nanotubes were measured and characterized. This study reported the field measurements during the development of carbon nanotube production. Monitoring data were taken and the sampling methods to characterize aerosol release were developed along with the modification of carbon nanotube production in a time period from 2006 to 2009. Particle number concentrations for diameters from 5 nm to 20 microm were measured using the fast mobility particle sizer and the aerodynamic particle sizer; the particles released from the furnace were found to be less than 500 nm in diameter. The morphology and elemental composition of the released nanoparticles were characterized by scanning and transmission electron microscopy and energy dispersive spectroscopy. Different operating conditions of multi-walled carbon nanotubes (MWCNT) production were studied to evaluate their effects on the number and morphology of aerosol particles, and the number of particles released. Carbon nanotube filaments and carbon particles in clusters were found among the released aerosol particles during production of multiwalled carbon nanotubes.

Summary of the findings from the exposure assessments for metalworking fluid mortality and morbidity studies.

Since 1985, a number of North American researchers have evaluated the association between worker exposure to metalworking fluids (MWFs) and cancer mortality or respiratory morbidity. The studies have used different methods to measure the MWF aerosol concentration and to evaluate the exposures to the specific components of the MWF aerosol (bacteria, endotoxin, elements, metals, ethanolamines, polyaromatic hydrocarbons). This diversity of approaches makes comparison of study results difficult and has impeded the development of an occupational exposure limit (OEL) for metalworking fluids. This article summarizes the exposures measured in these North American epidemiologic studies by estimating their thoracic and inhalable MWF particulate levels. In addition, issues that must be resolved before a universal sampling and analysis method for MWF can be recommended are reviewed, including: the use of gravimetric versus extractable analysis; whether the analytical limit of detection can support a lower occupational exposure limit; if the volatile components of mineral oils should also be collected; and whether there are components of specific concern in MWFs that should be regulated separately. Finally, recommendations for future directions in MWF exposure assessment and control are suggested.