Dengue Fever Culminating in Cardiac Arrest: A Case Report.

Infection from the dengue virus can manifest with a variety of clinical presentations. Cardiac involvement from dengue fever is a rarely reported phenomenon with significant morbidity and mortality. We illustrate the case of a 47-year-old male admitted to the hospital with fevers. The hospital course was complicated with cardiac arrest. Clinicians need to be weary of this rare occurrence particularly in areas with a known prevalence of dengue for prompt recognition and improved patient outcomes.

Congenital Anomaly Diagnosis of Typical Cardiac Chest Pain Due to Thebesian Veins Draining Into the Left Ventricular Chamber: A Case Report and Review of Literature.

Thebesian veins are microfistulae that drain the coronary arteries directly into one or more chambers of the heart. Persistence of these anomalous connections into adulthood can lead to shunting of blood away from the myocardium causing typical chest pain symptoms with electrocardiogram changes consistent with ischemia. We describe a case of a 77-year-old female who underwent ischemic evaluation for her symptoms found to have significant Thebesian veins. We also engage in a comprehensive review of the literature finding consistencies in the way these cases are presented in the literature.

Pericardial effusion in an immunocompetent host- a unique presentation of histoplasmosis.

Histoplasma capsulatum infection is infrequently considered in the differential diagnoses for acute pericarditis in immunocompetent hosts when presenting with tamponade physiology, given its gradual infective nature. We describe a case of a young male presenting solely with acute pericarditis with pericardial effusion and early cardiac tamponade physiology secondary to a pulmonary histoplasmosis infection. Our patient had no pulmonary symptoms; the only pulmonary manifestation of histoplasmosis included incidental findings of subcarinal lymphadenopathy and a left lingular nodule abutting the pericardium. Given failure of symptom improvement with pericardiocentesis and first-line therapy for idiopathic/viral pericarditis, further workup of the pulmonary nodule was pursued. Histopathologic analysis of tissue showed caseating granulomas and fungal Grocott-Gömöri's methenamine silver stain revealed yeast consistent with Histoplasma species. The patient improved with itraconazole therapy. Learning objective: Pulmonary histoplasmosis has potential to present as a pericardial effusion in the immunocompetent individual. In addition to pericardiocentesis, antifungal therapy can be curative.

Life cycle assessment of high-rate anaerobic treatment, microbial fuel cells, and microbial electrolysis cells.

Existing wastewater treatment options are generally perceived as energy intensive and environmentally unfriendly. Much attention has been focused on two new approaches in the past years, (i) microbial fuel cells and (ii) microbial electrolysis cells, which directly generate electrical current or chemical products, respectively, during wastewater treatment. These systems are commonly denominated as bioelectrochemical systems, and a multitude of claims have been made in the past regarding the environmental impact of these treatment options. However, an in-depth study backing these claims has not been performed. Here, we have conducted a life cycle assessment (LCA) to compare the environmental impact of three industrial wastewater treatment options, (i) anaerobic treatment with biogas generation, (ii) a microbial fuel cell treatment, with direct electricity generation, and (iii) a microbial electrolysis cell, with hydrogen peroxide production. Our analysis showed that a microbial fuel cell does not provide a significant environmental benefit relative to the "conventional" anaerobic treatment option. However, a microbial electrolysis cell provides significant environmental benefits through the displacement of chemical production by conventional means. Provided that the target conversion level of 1000 A.m(-3) can be met, the decrease in greenhouse gas emissions and other environmentally harmful emissions (e.g., aromatic hydrocarbons) of the microbial electrolysis cell will be a key driver for the development of an industrial standard for this technology. Evidently, this assessment is highly dependent on the underlying assumptions, such as the used reactor materials and target performance. This provides a challenge and an opportunity for researchers in the field to select and develop appropriate and environmentally benign materials of construction, as well as demonstrate the required 1000 A.m(-3) performance at pilot and full scale.

Comprehensive life cycle inventories of alternative wastewater treatment systems.

Over recent decades, the environmental regulations on wastewater treatment plants (WWTP) have trended towards increasingly stringent nutrient removal requirements for the protection of local waterways. However, such regulations typically ignore other environmental impacts that might accompany apparent improvements to the WWTP. This paper quantitatively defines the life cycle inventory of resources consumed and emissions produced in ten different wastewater treatment scenarios (covering six process configurations and nine treatment standards). The inventory results indicate that infrastructure resources, operational energy, direct greenhouse gas (GHG) emissions and chemical consumption generally increase with increasing nitrogen removal, especially at discharge standards of total nitrogen <5 mgN L(-1). Similarly, infrastructure resources and chemical consumption increase sharply with increasing phosphorus removal, but operational energy and direct GHG emissions are largely unaffected. These trends represent a trade-off of negative environmental impacts against improved local receiving water quality. However, increased phosphorus removal in WWTPs also represents an opportunity for increased resource recovery and reuse via biosolids applied to agricultural land. This study highlights that where biosolids displace synthetic fertilisers, a negative environmental trade-off may also occur by increasing the heavy metals discharged to soil. Proper analysis of these positive and negative environmental trade-offs requires further life cycle impact assessment and an inherently subjective weighting of competing environmental costs and benefits.

Nitrous oxide generation in full-scale biological nutrient removal wastewater treatment plants.

International guidance for estimating emissions of the greenhouse gas, nitrous oxide (N(2)O), from biological nutrient removal (BNR) wastewater systems is presently inadequate. This study has adopted a rigorous mass balance approach to provide comprehensive N(2)O emission and formation results from seven full-scale BNR wastewater treatment plants (WWTP). N(2)O formation was shown to be always positive, yet highly variable across the seven plants. The calculated range of N(2)O generation was 0.006-0.253 kgN(2)O-Nper kgN denitrified (average: 0.035+/-0.027). This paper investigated the possible mechanisms of N(2)O formation, rather than the locality of emissions. Higher N(2)O generation was shown to generally correspond with higher nitrite concentrations, but with many competing and parallel nitrogen transformation reactions occurring, it was very difficult to clearly identify the predominant mechanism of N(2)O production. The WWTPs designed and operated for low effluent TN (i.e. <10 mgN L(-1)) had lower and less variable N(2)O generation factors than plants that only achieved partial denitrification.