Essential Fatty Acid Deficiency in 2015: The Impact of Novel Intravenous Lipid Emulsions.

The fatty acids, linoleic acid (18:2ω-6) and α-linolenic acid (18:3ω-3), are essential to the human diet. When these essential fatty acids are not provided in sufficient quantities, essential fatty acid deficiency (EFAD) develops. This can be suggested clinically by abnormal liver function tests or biochemically by an elevated Mead acid and reduced linoleic acid and arachidonic acid level, which is manifested as an elevated triene/tetraene ratio of Mead acid/arachidonic acid. Clinical features of EFAD may present later. With the introduction of novel intravenous (IV) lipid emulsions in North America, the proportion of fatty acids provided, particularly the essential fatty acids, varies substantially. We describe a case series of 3 complicated obese patients who were administered parenteral nutrition (PN), primarily using ClinOleic 20%, an olive oil-based lipid emulsion with reduced amounts of the essential fatty acids, linoleic and α-linolenic, compared with more conventional soybean oil emulsions throughout their hospital admission. Essential fatty acid profiles were obtained for each of these patients to investigate EFAD as a potential cause of abnormal liver enzymes. Although the profiles revealed reduced linoleic acid and elevated Mead acid levels, this was not indicative of the development of essential fatty acid deficiency, as reflected in the more definitive measure of triene/tetraene ratio. Instead, although the serum fatty acid panel reflected the markedly lower but still adequate dietary linoleic acid content and greatly increased oleic acid content in the parenteral lipid emulsion, the triene/tetraene ratio remained well below the level, indicating EFAD in each of these patients. The availability and use of new IV lipid emulsions in PN should encourage the clinician to review lipid metabolism based on the quantity of fatty acids provided in specific parenteral lipid emulsions and the expected impact of these lipid emulsions (with quite different fatty acid composition) on measured fatty acid profiles.

Energy requirements and the use of predictive equations versus indirect calorimetry in critically ill patients.

Nutrition support has been shown to have a positive impact on critically ill patients who meet their defined goals of nutrition therapy. However, inappropriate energy assessment can contribute to under- or overfeeding resulting in deleterious effects. Thus, assessment of energy expenditure in critically ill patients is crucial to prevent negative impacts from inappropriate feeding. Currently, the optimal energy requirement and appropriate energy assessment in these patients is controversial. Indirect calorimetry or predictive equations have been suggested to evaluate energy expenditure in critically ill patients. Indirect calorimetry is a gold standard for evaluating energy expenditure, but it is not always available and has some limitations. Many predictive equations, therefore, have been developed to predict energy expenditure in critically ill patients. However, these equations cannot be used generally in these patients since they were developed in a unique patient population. Many studies compared measured energy expenditure with predictive energy expenditure, but the data regarding accuracy is not robust. Therefore, clinicians should consider using these equations carefully based on the current supporting data. Indirect calorimetry is recommended for use in evaluating energy expenditure in critically ill patients if it is available.

Amoebic liver abscess in USA: a population-based study of incidence, temporal trends and mortality.

BACKGROUND: Amoebic liver abscess (ALA) may be associated with significant morbidity and mortality, but nationwide American data is unavailable. Our objective was to describe ALA epidemiology and outcomes in USA from a population-based perspective. METHODS: Patients hospitalized with ALA between 1993 and 2007 were identified using the Nationwide Inpatient Sample. Patient characteristics, interventions and outcomes including mortality were determined. The annual incidence of ALA and temporal trends were determined using the negative binomial regression models. RESULTS: Between 1993 and 2007, 848 hospitalizations for ALA, corresponding to ∼4100 hospitalizations nationwide, were identified. The annual incidence was 1.38 per million population with a 2.4% [95% confidence interval (CI) 0-4.8%; P=0.06] average annual decline during this study. Most patients were hospitalized in western (54%) and southern states (27%), and 48% were Hispanic. Males (incidence rate ratio vs. females: 4.53; 95% CI 4.19-4.90) had the highest incidence rates. Percutaneous and surgical drainage was required in 48 and 7% of patients respectively. Although length of stay [median, 6 days; interquartile range (IQR) 4-10] and hospital charges (US$25,345; IQR US$15,030-42, 275) were substantial, in-hospital mortality was rare (0.8%). Females [odds ratio (OR) 6.12; CI 1.39-26.8], patients ≥ 60 years (OR 13.3; 95% CI 2.5-71.5), and those with ≥ 3 comorbidities (OR 5.80; 95% CI 1.30-25.8), particularly malnutrition, had an increased risk of death. CONCLUSIONS: ALA is rare and the incidence has decreased in USA. Young, Hispanic males in southwestern states are most frequently affected. Mortality caused by ALA is lower than what was reported previously.

A population-based study of pyogenic liver abscesses in the United States: incidence, mortality, and temporal trends.

OBJECTIVES: Few population-based studies have evaluated pyogenic liver abscess (PLA) in North America. We assessed the incidence of PLA and evaluated predictors of mortality. METHODS: We used the Nationwide Inpatient Sample to identify all patients with discharges for PLA (ICD-9 572.0) between 1994 and 2005. Multivariable logistic regression analysis was performed to determine whether mortality was associated with patient and hospital characteristics including comorbidities, interventions, and bacterial cultures. We determined the annual incidence for PLA in the US population and assessed for temporal changes using generalized linear regression models. RESULTS: We identified 17,787 PLA discharges for an overall incidence of PLA of 3.6 (95% confidence interval (CI): 3.5-3.7) per 100,000 population. From 1994 to 2005, the annual average percent increase in incidence was 4.1% (95% CI: 3.4-4.8; P<0.0001). In-hospital mortality was 5.6% (95% CI: 5.3-6.0). Mortality was associated with older age (65-84 vs. 18-34: odds ratio (OR)=2.28 (1.48-3.51)); Medicaid (OR=1.74 (1.36-2.23)) and Medicare (OR=1.48 (1.18-1.85) vs. private insurance; and comorbidities such as cirrhosis (OR=2.48 (1.85-3.31)), chronic renal failure (OR=1.99 (1.28-3.09)), and cancer (OR=2.32 (1.97-2.73)). Patients who underwent percutaneous liver aspiration (OR=0.45 (0.39-0.52)) had lower mortality, whereas surgical drainage (OR=0.87 (0.68-1.10)) and endoscopic retrograde cholangiopancreatography (OR=0.73 (0.52-1.03)) were not associated with mortality. The most commonly recorded bacterial infections were Streptococcus species (29.5%) and Escherichia coli (18.1%). Patients with bacteremia or septicemia (OR=3.88 (3.36-4.48)) had an increased risk of death. CONCLUSIONS: The incidence of PLA is increasing and is associated with significant mortality that is attributable to several modifiable risk factors.

Secreted bioactive factors from Bifidobacterium infantis enhance epithelial cell barrier function.

Live probiotic bacteria are effective in reducing gut permeability and inflammation. We have previously shown that probiotics release peptide bioactive factors that modulate epithelial resistance in vitro. The objectives of this study were to determine the impact of factors released from Bifidobacteria infantis on intestinal epithelial cell permeability and tight junction proteins and to assess whether these factors retain their bioactivity when administered to IL-10-deficient mice. B. infantis conditioned medium (BiCM) was applied to T84 human epithelial cells in the presence and absence of TNF-alpha and IFN-gamma. Transepithelial resistance (TER), tight junction proteins [claudins 1, 2, 3, and 4, zonula occludens (ZO)-1, and occludin] and MAP kinase activity (p38 and ERK) were examined. Acute effects of BiCM on intestinal permeability were assessed in colons from IL-10-deficient mice in Ussing chambers. A separate group of IL-1-deficient mice was treated with BiCM for 4 wk and then assessed for intestinal histological injury, cytokine levels, epithelial permeability, and immune response to bacterial antigens. In T84 cells, BiCM increased TER, decreased claudin-2, and increased ZO-1 and occludin expression. This was associated with enhanced levels of phospho-ERK and decreased levels of phospho-p38. BiCM prevented TNF-alpha- and IFN-gamma-induced drops in TER and rearrangement of tight junction proteins. Inhibition of ERK prevented the BiCM-induced increase in TER and attenuated the protection from TNF-alpha and IFN-gamma. Oral BiCM administration acutely reduced colonic permeability in mice whereas long-term BiCM treatment in IL-10-deficient mice attenuated inflammation, normalized colonic permeability, and decreased colonic and splenic IFN-gamma secretion. In conclusion, peptide bioactive factors from B. infantis retain their biological activity in vivo and are effective in normalizing gut permeability and improving disease in an animal model of colitis. The effects of BiCM are mediated in part by changes in MAP kinases and tight junction proteins.