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Production of ethylene (C2H4) from Carbon dioxide (CO2) is a promising and effective approach for mitigating the adverse greenhouse effect of anthropogenic CO2 emission from human activities including chemical industries along with energy deficiency caused by the burning of nonrenewable fossil fuels. The C2H4, one of the utmost extensively employed chemical compounds, is readily converted into various valuable products that can substitute those derived from fossil fuels. Electrochemical reduction is a process of converting CO2 into C2H4 in which the electrocatalysts, electrolyzer and electrolyte all play the critical role. Despite considerable improvements in electrochemical CO2 reduction but its efficacy is still hindered by a number of complications, including the deprived mass transfer efficiency of the electrolyzer, the high cost, low activity, poor stability and limited selectivity of electrocatalysts towards C2H4. Accomplishments to date in CO2 electroreduction to C2H4 have been inspiring, while extensive advances are still required for it to develop a profitable technology able to move society towards renewable energy sources. The current review demonstrates a unified discussion on recent progress in the area of CO2 reduction to C2H4. The role of a class of promising advanced electrocatalysts, electrolytes and the design of electrolyzer in the electrochemical reduction method is thoroughly reviewed. We also highlight the current developments in photocatalytic CO2 reduction to C2H4. Lastly, this review is concluded by deliberating the current challenges that are encountered during the production of C2H4 from CO2 electrochemical reduction with an objective of revolutionary futuristic developments. This article will provide comprehensive knowledge to the readers on CO2 electrochemical reduction to C2H4 production.

Owing to rich-redox chemistry, metal-N4-molecular catalysts have been found as promising electrocatalysts for oxygen reduction reaction (ORR), however, de-metalation of the metal atom from N4-cavity in the electrolyte limits their activity and endurance. Herein, a MnN4-macrocyclic complex was prepared and characterized via various techniques. The results of analytical and theoretical studies suggest that the MnN4-macrocyclic complex has saddle-shaped geometry. Further, this complex was incorporated with black carbon (MnN4@CB) and studied for electrocatalytic ORR in alkaline media. The MnN4@CB composite displayed comparable ORR formal potential (−0.14 V vs Ag/AgCl) to the traditional 20% Pt/C catalyst (−0.13 V vs Ag/AgCl) and remarkable methanol tolerance. Theoretical studies revealed that the highest occupied molecular orbital (HOMO) of MnN4 has almost the same energy as the π∗ orbital of an O2 molecule, resulting in optimal coupling between HOMO and π∗ orbital, leading to efficient ORR. The charge distribution and 2D Fourier optimization of the MnN4-complex suggested that the N-donor atoms increased the electron density on Mn-atom, and transferred into the π∗ orbital of O2, weakening the O–O bond during ORR. In addition to developing low-cost ORR electrocatalysts, this work will contribute to defining their activity descriptors.

In this work, we designed a novel Bi2MoO6/Bi2MoO6-x homojunction photocatalyst and successfully fabricated by a facile solvothermal-calcination approach. Experimental characterizations indicated that the formation of Bi2MoO6/Bi2MoO6-x homojunction was caused by controlling oxygen vacancies formation. Such Bi2MoO6/Bi2MoO6-x homojunction exhibits about 240 times higher photocatalytic activity towards phenol degradation as compared with pure Bi2MoO6 under visible light irradiation. Similarly, for a co-existed phenol and Cr(VI) model system, Bi2MoO6/Bi2MoO6-x-catalyzed the photodegradation of phenol and the reduction of Cr(VI) simultaneously occur, and Bi2MoO6/Bi2MoO6-x homojunction also displays a superior photocatalytic activity, that is 4 and 8 times higher than pure Bi2MoO6, respectively. The remarkably boosted photocatalytic activity could be attributed primarily to the highly efficient separation of photogenerated electrons/holes due to the homojunction and the synergistic effect between phenol oxidation and Cr(VI) reduction. Thus, the present insight provides an effective strategy for designing and preparing highly active photocatalysts with the incorporation of oxygen vacancies modulation and applying for environmental remediation.

Cryptococcal infection has been documented in 2.8% of solid-organ transplant recipients, with the median time to disease onset being 21 months. Renal transplant recipients account for the majority of cases. Most patients present with central nervous system or disseminated disease, with only a minority having cutaneous manifestations. We present the case of a 47-year-old female renal transplant recipient who presented with refractory acute cellulitis 7 months after transplant. She had received thymoglobulin induction and was on a maintenance immunosuppressive regimen of tacrolimus, mycophenolic acid, and prednisone (5 mg/d). She did not respond to broad-spectrum antibacterial therapy for presumed bacterial cellulitis. Skin and soft tissue biopsies subsequently showed the presence of yeast; Cryptococcus neoformans was recovered in culture. Blood cultures, chest radiography, and cerebrospinal fluid sampling were negative, which resulted in a diagnosis of multifocal soft tissue cryptococcosis, a form of disseminated disease. Serum cryptococcal antigen testing was strongly positive (≥ 1:2560). The patient's immunosuppression was reduced, and she received treatment with liposomal amphotericin B and flucytosine for 2 weeks, which resulted in symptomatic improvement. This was followed by 1 year of consolidation and subsequent maintenance therapy with fluconazole. This case should increase awareness of the broader differential diagnosis of soft tissue infection in immunocompromised patients. Her case mimicked bacterial cellulitis, which delayed administration of effective therapy. Although our patient was initially diagnosed via biopsy, early clinical suspicion and serum cryptococcal antigen testing can lead to the correct diagnosis more rapidly. As transplant patients return to their community providers, heightened vigilance for unusual infections and presentations is warranted. The possibility of a cryptococcal cause for acute soft tissue infection should be considered, even in the absence of pulmonary or central nervous system involvement.

Ammonia (NH3) plays a significant role in fertilizer production to support the ever-increasing population and serves as a renewable energy carrier as well as a zero-carbon emission fuel. Currently, NH3 is produced by a non-sustainable and highly energy-intensive process. Among the available alternatives, the electrochemical nitrogen reduction reactions (NRR) has attracted attention due to the compact and on-site electrolytic cells that can operate from solar or wind power under ambient conditions but still suffer from relatively low Faraday efficiency and NH3 yields. For the commercialization of electrocatalytic NRR, a catalytic material demonstrating a FE ∼50% and an NH3 yield rate of ∼10−6 mol s−1 cm−2 is suggested. Various strategies, including amorphization, structural engineering, catalyst-support interactions and hydrogen evolution suppression over catalytic materials, have been presented to enhance the electrocatalytic NRR. In this review, the current progress of various identified NRR electrocatalysts (including metal carbides, nitrides, oxides, phosphides, sulfides, selenides, borides, bimetallic materials, metal-organic frameworks, and metal-free materials) is summarized by collectively focusing on both theoretical analysis and experimental investigations. For further development of rational catalysts, a collaboration of theoretical and experimental studies, advanced characterization techniques, understanding of the electrocatalytic mechanism, efficient screening systems, and precise detection methods are needed. Specially designed electrocatalysts can improve NRR activity by regulating the cathodic reactions. The challenges and future perspectives have been described with special emphasis on various transition metal-based electrocatalysts for N2 fixation.

Among the possible products of CO2 electrochemical reduction, CO plays a unique and vital role, which can be an ideal feedstock for further reduction to C2+ products, and also the important component of syngas that can be used as feedstock for value-added chemicals and fuels. However, it is still a challenge to tune the CO selectivity on Cu electrode. Here we newly construct an ultrasound-assisted electrochemical method for CO2 reduction, which can tune the selectivity of CO2 to CO from less than 10% to greater than 80% at -1.18 V versus (vs.) reversible hydrogen electrode (RHE). The partial current density of CO production is significantly improved by 15 times. By in-situ Raman study, the dominating factor for the improved CO production is attributed to the accelerated desorption of *CO intermediate. This work provides a facile method to tune the product selectivity in CO2 electrochemical reduction.

Although still poorly understood, electrolytes can play a key role in obtaining the desired product from the electrochemical reduction of CO2. To address this issue, it is of great significance to better understand the relationship between the selectivity and the activity of the reaction and the electrode structure and the electrolyte. Herein, the influence of electrolytes, especially those that contain halide ions, on the CO2 reduction performance was studied using Cu-based electrodes with various surface components, including Cu0, Cu+ and a mixed state of Cu0, Cu+ and Cu2+. The results show that Cl− and Br− improved the CH4 selectivity for all tested Cu-based electrodes, while the effect of I− was very sensitive to the surface state of Cu. On the one hand, I− could corrode Cu2O and form CuI, which could stabilize Cu+, resulting in a higher faradaic efficiency for C2H4. On the other hand, I− had a negative effect on C2H4 selectivity in the presence of Cu0 and Cu2+. When Cu+ was present on the electrode surface, the ratio of C2H4/CH4 was significantly changed from 19.3 (in KHCO3 electrolyte) to 372.1 (in KHCO3 + KI electrolyte). Our findings improve the understanding of the cooperation between the catalyst and halide electrolytes to produce the desired product and, in particular, the C2 product.

It is still poorly understood how the first intermediates of CO2 reduction are formed and converted to multi-carbon products over Cu-based electrodes. Herein, Ag is used to decorate dendritic Cu and a high Faradaic efficiency (FE) for C2 H4 (25 %) is obtained on a CuAg electrode, which is about five times higher than dendritic Cu. The intermediates including *CO2 - , OH groups, Cu-CO, C-O rotation, and CHx species are investigated by in situ Raman spectroscopy. This work provides spectroscopic evidence that the first intermediate of CO2 reduction on Ag-decorated Cu is carboxylate anion *CO2 - bonded with the catalyst surface through the C and O atom. The formation and evolution process of the *CO2 - intermediate over the applied potential are investigated in depth as well. This research contributes to a better understanding of the mechanism of CO2 reduction and multi-carbon product formation pathways over Ag-decorated Cu.

Visible-light-driven photoelectrochemical (PEC) catalysis has been widely studied as a promising technique for the degradation of organic pollutants in wastewater. Herein, we report a sulfite-enhanced PEC degradation process for the degradation of organic pollutant. The degradation rate was significantly enhanced by ～30 times with the addition of 16 mM sulfite. The Electron Spin Resonance (ESR), Transient Absorption (TA) and hole scavenger studies showed that sulfite radicals ( S O 3 ⦁ - ) were the main reactive species in the reactions. The pollutant degradation pathway was studied by in-situ techniques and mass spectrometer, showing that the sulfite addition can promote the cleavage of aromatic ring C C bond and C N bond.

This chapter provides an overview of what antiretroviral therapy (ART) is and the current treatment guidelines according to the US Department of Health and Human Services and the International Antiviral Society-USA. Important criteria in selecting an initial treatment regimen are discussed as well as when to switch or simplify the regimen. Factors to consider when selecting an antiretroviral regimen and other information involving ART is presented to the reader via tables.

In this work, we designed a novel Bi

Graphical abstract Ultrasound significantly accelerate the desorption of *CO resulting in high CO selectivity., Among the possible products of CO2 electrochemical reduction, CO plays a unique and vital role, which can be an ideal feedstock for further reduction to C2+ products, and also the important component of syngas that can be used as feedstock for value-added chemicals and fuels. However, it is still a challenge to tune the CO selectivity on Cu electrode. Here we newly construct an ultrasound-assisted electrochemical method for CO2 reduction, which can tune the selectivity of CO2 to CO from less than 10% to >80% at −1.18 V versus (vs.) reversible hydrogen electrode (RHE). The partial current density of CO production is significantly improved by 15 times. By in-situ Raman study, the dominating factor for the improved CO production is attributed to the accelerated desorption of *CO intermediate. This work provides a facile method to tune the product selectivity in CO2 electrochemical reduction.

Summary Recently, the environmental impacts of microplastics have received extensive attention owing to their accumulation in the environment. However, developing efficient technology for the control and purification of microplastics is still a big challenge. Herein, we investigated the photocatalytic degradation of typical microplastics such as polystyrene (PS) microspheres and polyethylene (PE) over TiO2 nanoparticle films under UV light irradiation. TiO2 nanoparticle film made with Triton X-100 showed complete mineralization (98.40%) of 400-nm PS in 12 h, while degradation for varying sizes of PS was also studied. PE degradation experiment presented a high photodegradation rate after 36 h. CO2 was found as the main end product. The degradation mechanism and intermediates were studied by in situ DRIFTS and HPPI-TOFMS, showing the generation of hydroxyl, carbonyl, and carbon-hydrogen groups during the photodegradation of PS. This study provides a green and cost-efficient strategy for the control of microplastics contamination in the environment., Graphical Abstract, Highlights • Efficient degradation of microplastics under UV light by TiO2 film • Triton-based TiO2 film showed higher photocatalytic performance • The role of radical species during microplastics degradation was elucidated • Degradation mechanism and reaction intermediates were explored, Catalysis; Environmental Chemistry; Nanomaterials

SO2 and CO2 emitted from using of fossil fuels are causing serious environmental issues. Herein we put forward a promising strategy to realize CO2 reduction and SO2 removal simultaneously through a photoelectrochemical (PEC) process based on nanoelectrodes. In the present work, SO2 was oxidized to SO42− on BiVO4 photoanode after being absorbed by NaHCO3 solutions. At the same time, CO2 reduction occurred on nanoflower-like copper-indium alloy cathode. The absorption efficiency of SO2 was greater than 95%, and SO32− was oxidized to SO42− with oxidation efficiency about 50% in 3 h. Moreover, the energy of SO2 was recycled to assist the CO2 reduction on the cathode, consequently, the photocurrent densities were increased at least 3 times after introducing SO2. CO2 reduction with CO and HCOOH as main products was improved significantly when SO2 removal was conducted simultaneously. In-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) experiments were also performed to study the adsorption and conversion of SO2 on BiVO4 nanoparticles. The proposed approach could efficiently remove SO2 and recycle the energy of it to reduce CO2 into useful chemicals. This work provides a sustainable strategy for dealing with CO2 and SO2 in the flue gas by combining desulfurization and CO2 reduction in one PEC cell using nanoelectrodes.

The excessive utilization of fossil fuels accompanied by large amounts of anthropogenic CO2 emissions have led to adverse global environmental changes and a growing global energy crisis. Hence, converting CO2 into high-value chemical fuels, such as CO, CH4, HCOOH, and CH3OH, through catalysis is one of the most attractive topics in energy conversion. Among various approaches, electrochemical (EC) and photoelectrochemical (PEC) reduction are considered to be promising methods. Over the past decades, research in the area of CO2 EC and PEC reduction has been growing quickly. Herein, highly efficient nanostructured metals, metal alloys, metal oxides, metal-free electrodes, and photoelectrodes developed in recent years are discussed in detail in this review. Additionally, the strategies and mechanisms for improving the faradaic efficiency (FE), current density, and stability of catalysts are also discussed. The challenges and future perspectives for CO2 EC and PEC reduction are also discussed.

The current diagnosis of infective endocarditis (IE) is based on the modified Duke criteria, which has approximately 80% sensitivity for the diagnosis of native valve endocarditis (NVE), with lower sensitivity for the diagnosis of prosthetic valve endocarditis (PVE) and culture-negative endocarditis. There is preliminary evidence that 18F-FDG PET/CT is an adjunctive diagnostic test with high accuracy reported in small studies to date. We therefore performed a meta-analysis of studies evaluating the use of PET/CT in the diagnosis of IE to establish a more precise estimate of accuracy. PubMed, Embase, Cochrane library, CINAHL, Web of Knowledge, and www.clinicaltrials.gov were searched from January 1990 to April 2017 for studies evaluating the accuracy of PET/CT for the evaluation of possible IE. We identified 13 studies involving 537 patients that were included in the meta-analysis. The pooled sensitivity of PET/CT for diagnosis of IE was 76.8% (95% CI 71.8–81.4%; Q = 39.9, P

We performed a meta-analysis evaluating the use of fluorine-18-fluorodeoxyglucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) in the diagnosis of cardiovascular implantable electronic device (CIED) infections. PET/CT may be helpful in the diagnosis of CIED infection, particularly in patients with the absence of localizing signs or definitive echocardiographic findings. PubMed, Embase, Cochrane library, CINAHL, Web of Knowledge, and www.clinicaltrials.gov from January 1990 to April 2017 were searched for studies evaluating the accuracy of PET/CT in the diagnosis of CIED infections. Overall, 14 studies involving 492 patients were included in the meta-analysis. The pooled sensitivity of PET/CT for diagnosis of CIED infection was 83% (95% CI 78%-86%) and the pooled specificity was 89% (95% CI 84%-94%). PET/CT demonstrated a higher sensitivity of 96% (95% CI 86%-99%) and specificity of 97% (95% CI 86%-99%) for diagnosis of pocket infections. Diagnostic accuracy for lead infections or CIED-IE was lower with pooled sensitivity of 76% (95% CI 65%-85%) and specificity of 83% (95% CI 72%-90%). Use of PET/CT in the evaluation of CIED infection has both a high sensitivity (83%) and specificity (89%) and deserves consideration in the management of selected patients with suspected CIED infections.

It is still poorly understood how the first intermediates of CO

Upon completion of this chapter, the reader should be able to • Discuss categories of regimens for first-line antiretroviral therapy. • Recognize the basis for the US Department of Health and Human Services (USDHHS) guidelines for initial antiretroviral therapy. • Recognize and apply recommended regimens for initiation of antiretroviral therapy....

Despite the increased awareness of heterogeneous reaction on mineral dust, the knowledge of how the intensity of solar irradiation influences the photochemistry activity remains a crucially important part in atmospheric research. Relevant studies have not seriously discussed the photochemistry under weak sunlight during haze, and thus ignored some underlying pollution and toxicity. Here, we investigated the heterogeneous formation of nitrate and nitrite under various illumination conditions by laboratory experiments and field observations. Observed by in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), water-solvated nitrate was the main surface product, followed by other species varying with illumination condition. The growth of nitrate formation rate tends to be slow after the initial fast with increasing light intensity. For example, the geometric uptake coefficient (γgeo) under 30.5 mW/cm2 (5.72 × 10−6) has exceeded the 50 % of that under 160 mW/cm2 (1.13 × 10−5). This case can be explained by the excess NO2 adsorption under weak illumination while the excess photoinduced active species under strong irradiation. Being negatively associated with nitrate (R2 = 0.748, P

Conversion of CO 2 into fuels and chemicals via electroreduction has attracted significant interest. Via mesostructure design to tune the electric field distribution in the electrode, it is demonstrated that the Cu-In alloy with an inverse opal (CI-1-IO) structure provides efficient electrochemical CO 2 reduction and allows for sensitive detection of the CO 2 reduction intermediates via surface-enhanced Raman scattering. The significant enhancement of Raman signals of the intermediates on the CI-1-IO surface can be attributed to electric field enhancement on the "hot edges" of the inverse opal structure. Additionally, a highest CO 2 reduction faradaic efficiency (FE) of 92% (sum of formate and CO) is achieved at-0.6 V vs. RHE on the CI-1-IO electrode. The diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) results show that the Cu-In alloy with an inverse opal structure has faster adsorption kinetics and higher adsorption capacity for CO 2. The "hot edges" of the bowl-like structure concentrate electric fields, due to the high curvature, and also concentrate K + on the active sites, which can lower the energy barrier of the CO 2 reduction reaction. This research provides new insight into the design of materials for efficient CO 2 conversion and the detection of intermediates during the CO 2 reduction process.

Bisphenol A (BPA) is known as an endocrine-disrupting chemical, generally present in the environment. It has a harmful effect on aquatic lives and human health, therefore it is needful to exploit highly efficient innovative treatment methods for its removal. Herein, we report a Co-BiVO4 photoanode to activate peroxymonosulfate (PMS) for the complete removal of BPA via a photoelectrochemical (PEC) process. The Co-BiVO4 could degrade 99.16% of BPA in the presence of 2 mM PMS within 60 min, whereas the degradation rate constant is 0.08034 min−1, which was 20.86 times higher than the electrocatalytic (EC) and 5.35 times higher than the photocatalytic (PC) process. Notably, Co-BiVO4 showed significant activity toward PMS activation and BPA degradation as compared to other synthesized photocatalysts. Their photoelectrocatalytic performance followed the sequence Co-BiVO4 > Fe-BiVO4 > Ni-BiVO4 > pure-BiVO4 > without catalysts. Several influencing factors on the decomposition process, such as the effect of PMS concentration, applied potential, illumination time, initial pH, BPA concentration, Co loading, and co-existing anions were studied in detail. Radical scavenging experiment and transient absorption result showed that sulfate radicals (SO4•─) were the dominant reactive species. Moreover, a significant synergistic effect was noticed in Co-BiVO4/PEC/PMS system for BPA degradation. Degradation mechanism and reaction intermediates were studied by in-situ diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS) and liquid chromatography-mass spectroscopy (LC-MS) presenting the enhanced bond cleavage in PEC activated PMS system. The BPA showed 92.47% and 87.27% removal in tap and river water samples after 60 min of reaction using Co-BiVO4/PMS PEC system. Our finding proposed an efficient method for wastewater treatment in an eco-friendly way.

Increased risk of invasive pulmonary aspergillosis after influenza infection has been reported; however data are limited. To describe Invasive fungal infections (IFI) associated with preceding respiratory viral infection at a large referral center. We reviewed all IFI cases among patients with positive influenza and/or RSV nasopharyngeal/lower respiratory tract PCR from October 2015 to December 2016. Cases of pulmonary IFI were classified as possible, probable, and definite based on EORTC-MSG definitions. We identified 8 cases (4 influenza, 4 RSV); 3 with probable Aspergillosis, 1 possible Aspergillosis, 1 probable Histoplasmosis, 1 probable Mucormycosis, and 2 possible IFI (consistent clinical and imaging findings). Half of our patients were men with a mean age of 64 years (SD 8) and median Charlson Comorbidity Score of 3.5 (IQR 3-7). Most common risk factors were stem cell transplant (75%) and neutropenia (62.5%). Four patients were on antifungal prophylaxis at presentation. All patients received anti-viral therapy with oseltamivir/ribavirin and 50% received empiric antibiotics. Median duration from onset of viral infection to diagnosis of IFI was 8.5 days (IQR 2.5-14) and 75% were diagnosed during the same admission. All received antifungal therapy; 62.5% required ICU care, and 37.5% died during index hospitalization. Our study supports earlier observations describing IFI following respiratory viral infection in immunocompromised hosts. Secondary IFI occurred in 1.4% of our cohort and most occurred during the index admission. IFI following viral illness is associated with high mortality and early detection and therapy may improve outcomes.

Mycobacterium genavense is a non-tuberculous mycobacterium which can rarely cause disease in non-HIV immunocompromised hosts. We describe our experience with this unusual infection and perform a systematic review of the literature to describe the features of M. genavense infection in non-HIV immunocompromised hosts.All cases of Mycobacterium genavense infection in non-HIV patients at our institution were reviewed. In addition, we conducted a systematic review of the literature to identify previously published cases of M. genavense infections in non-HIV hosts.Two cases of M. genavense were identified at our center; a 51-year-old renal transplant recipient with a prosthetic knee joint infection and a 66-year-old woman with idiopathic CD4 lymphocytopenia with gastrointestinal tract disease. The systematic review identified 44 cases of M. genavense infection in non-HIV hosts. The most common underlying conditions were solid organ transplantation (40%), sarcoidosis (14%) and hematopoietic stem cell transplantation (7%). Disease most commonly involved the gastrointestinal tract, spleen, liver or bone marrow. Diagnosis was challenging with PCR required for identification in nearly all cases. Over one-third of patients died, which may reflect the combination of infection and underlying comorbidities. Overall cure was achieved in 61% with a mean duration of antimycobacterial therapy of 15.5 months (range 10-24).M. genavense infection is a rare mycobacterial infection in non-HIV immunocompromised hosts. It should be suspected in immunocompromised patients presenting with disseminated mycobacterial infection, acid fast bacilli on smear or histopathologic examination, with poor or no growth in mycobacterial cultures.

Empyema necessitans is a complication of a pleural space infection that dissects through the pleura into the soft tissues of the chest and skin. Due to the widespread availability of antibiotics, empyema necessitans is rare in modern medicine and is most commonly caused by Mycobacterium tuberculosis. A 38-year-old immunocompetent male presented with left shoulder pain and his chest radiograph revealed a mass in the upper left lung and/or pleural space. He underwent multiple debridements of the chest wall due to a left chest wall abscess and empyema necessitans. All operative samples were positive for Streptococcus agalactiae (Group B Streptococcus). The patient's clinical course was complicated by septic arthritis of the left sternoclavicular joint and first rib, vertebral osteomyelitis/discitis, and pelvic abscesses. This case report illustrates the pathogenic process of empyema necessitans and summarizes the clinical management for practicing clinicians. It also documents the second case of Streptococcus agalactiae-associated empyema necessitans, to our knowledge, with significantly greater disease extension than the first.

We performed a meta-analysis evaluating the use of fluorine-18-fluorodeoxyglucose (PET/CT may be helpful in the diagnosis of CIED infection, particularly in patients with the absence of localizing signs or definitive echocardiographic findings.PubMed, Embase, Cochrane library, CINAHL, Web of Knowledge, and www.clinicaltrials.gov from January 1990 to April 2017 were searched for studies evaluating the accuracy of PET/CT in the diagnosis of CIED infections.Overall, 14 studies involving 492 patients were included in the meta-analysis. The pooled sensitivity of PET/CT for diagnosis of CIED infection was 83% (95% CI 78%-86%) and the pooled specificity was 89% (95% CI 84%-94%). PET/CT demonstrated a higher sensitivity of 96% (95% CI 86%-99%) and specificity of 97% (95% CI 86%-99%) for diagnosis of pocket infections. Diagnostic accuracy for lead infections or CIED-IE was lower with pooled sensitivity of 76% (95% CI 65%-85%) and specificity of 83% (95% CI 72%-90%).Use of PET/CT in the evaluation of CIED infection has both a high sensitivity (83%) and specificity (89%) and deserves consideration in the management of selected patients with suspected CIED infections.