Effect of parenteral lipids on essential fatty acid deficiency in pediatric intestinal failure: A retrospective cohort study.

BACKGROUND: Pediatric patients with intestinal failure require long-term parenteral nutrition owing to impaired enteral nutrition absorption. A potential complication is essential fatty acid deficiency (EFAD), resulting from decreased linoleic and α-linolenic acid concentrations and defined by an increased triene:tetraene ratio (TTR; Mead acid:arachidonic acid). Historically, soybean oil lipid emulsion (SOLE) was the only commercially available parenteral lipid in the United States. Recently, a composite lipid emulsion (CLE) and fish oil lipid emulsion (FOLE) received US Food and Drug Administration approval. This study investigated whether lipid emulsion regimen impacts EFAD incidence in pediatric patients with intestinal failure. METHODS: This study was a 10-year retrospective cohort study of pediatric patients with intestinal failure who received parenteral SOLE, CLE, or FOLE. The primary outcome was EFAD incidence, defined as a TTR ≥ 0.2. Secondary outcomes included TTR ≥ 0.05, cholestasis incidence, lipid dose effect on EFAD incidence, and fatty acid parameter differences. RESULTS: A total of 144 fatty acid profiles from 47 patients were reviewed. EFAD did not occur in any lipid emulsion group. There were no differences in the incidence of TTR ≥ 0.05 or cholestasis. The effect of dose could not be evaluated because of no EFAD incidence. Lastly, although each group had varied fatty acid parameters, none saw decreased essential fatty acid levels. CONCLUSION: This study found that, with close monitoring, the lipid emulsion regimen did not impact EFAD incidence. This suggests that FOLE and CLE do not increase EFAD risk compared with SOLE in pediatric patients with intestinal failure.

The Dysregulation of Essential Fatty Acid (EFA) Metabolism May Be a Factor in the Pathogenesis of Sepsis.

I propose that a deficiency of essential fatty acids (EFAs) and an alteration in their (EFAs) metabolism could be a major factor in the pathogenesis of sepsis and sepsis-related mortality. The failure of corticosteroids, anti-TNF-α, and anti-interleukin-6 monoclonal antibodies can be attributed to this altered EFA metabolism in sepsis. Vitamin C; folic acid; and vitamin B1, B6, and B12 serve as co-factors necessary for the activity of desaturase enzymes that are the rate-limiting steps in the metabolism of EFAs. The altered metabolism of EFAs results in an imbalance in the production and activities of pro- and anti-inflammatory eicosanoids and cytokines resulting in both hyperimmune and hypoimmune responses seen in sepsis. This implies that restoring the metabolism of EFAs to normal may form a newer therapeutic approach both in the prevention and management of sepsis and other critical illnesses.

Perspective on Emerging Micronutrient Deficiencies in Latin America and the Caribbean.

The moral imperative of public health systems is to maximize the health and welfare of the population to the extent possible. Constraints often include a lack of resources, political will, popular acceptance, or an acceptable safety margin. Major agencies have established iron, iodine, and vitamin A as the principal elements for micronutrients, with folate and zinc on the second plane. As the armamentarium of interventions to favor micronutrient nutrition, for example, preventive health measures, dietary improvement, forms of fortification, and nutrient supplements, is offered in public health policy. The utility of their merger with other nutrients, emergent nutrients, has been considered. The Latin America and Caribbean Region has unique characteristics. The scientific and epidemiology considerations for action in the Region's health concern on 4 emergent nutrient deficiencies of public health-vitamins D and E, essential fatty acids, and choline-are reviewed.

Plain language titleMicronutrient Deficiencies of Interest in Latin America and the CaribbeanPlain language summaryThe diets consumed in the diverse corners and societies in the nations of Latin America and the Caribbean area do not fully supply the vitamins and minerals needed by people of all ages and conditions. Some public health actions are being taken, but only against a limited selection of such nutrients as iron, vitamin A, iodine, and folic acid. The composition of diets and environmental conditions across the region suggests that 4 additional nutrients might be candidates for public health efforts. These include vitamin D, vitamin E, certain large fatty acid molecules, and choline.

Essential Fatty Acid Deficiency Is Common After Total Pancreatectomy and Islet Autotransplantation.

OBJECTIVES: Total pancreatectomy and islet autotransplantation (TPIAT) for pancreatitis may induce risk for essential fatty acid deficiency (EFAD) due to exocrine pancreatic insufficiency and intestinal alterations. The prevalence of EFAD post-TPIAT is currently unknown. METHODS: We abstracted essential fatty acid (EFA) profiles (n = 332 samples) for 197 TPIAT recipients (72% adult, 33% male). Statistical analyses determined the prevalence of, and associations with, EFAD post-operatively. EFAD was defined as a Triene-to-Tetraene ratio ≥0.05 if <18 years old, or ≥0.038 if ≥18 years old. RESULTS: Prevalence of EFAD was 33%, 49%, and 53.5% at 1, 2, and ≥3 years. At 1-year post-TPIAT, older age at transplant ( P = 0.03), being an adult versus a child ( P = 0.0024), and obstructive etiology ( P = 0.0004) were significant predictors of EFAD. Only 6% of children had EFAD 1-year post-TPIAT versus 46% of adults. The alpha-linolenic acid levels were lower with lower body mass index at transplant ( P = 0.011). EFAD was associated with the presence of other intestinal diseases ( P < 0.0001). CONCLUSIONS: One-third of individuals had EFAD 1-year post-TPIAT, highlighting the need for systematic monitoring. Older age at transplant increased risk and adults were more affected than children. Other diagnoses affecting intestinal health may further increase risk for EFAD.

Role for animal models in understanding essential fatty acid deficiency in cystic fibrosis.

Essential fatty acid deficiency has been observed in most patients with Cystic Fibrosis (CF); however, pancreatic supplementation does not restore the deficiency, suggesting a different pathology independent of the pancreas. At this time, the underlying pathological mechanisms are largely unknown. Essential fatty acids are obtained from the diet and processed by organs including the liver and intestine, two organs significantly impacted by mutations in the cystic fibrosis transmembrane conductance regulator gene (Cftr). There are several CF animal models in a variety of species that have been developed to investigate molecular mechanisms associated with the CF phenotype. Specifically, global and systemic mutations in Cftr which mimic genotypic changes identified in CF patients have been generated in mice, rats, sheep, pigs and ferrets. These mutations produce CFTR proteins with a gating defect, trafficking defect, or an absent or inactive CFTR channel. Essential fatty acids are critical to CFTR function, with a bidirectional relationship between CFTR and essential fatty acids proposed. Currently, there are limited analyses on the essential fatty acid status in most of these animal models. Of interest, in the mouse model, essential fatty acid status is dependent on the genotype and resultant phenotype of the mouse. Future investigations should identify an optimal animal model that has most of the phenotypic changes associated with CF including the essential fatty acid deficiencies, which can be used in the development of therapeutics.

Complementary Foods and Milk-Based Formulas Provide Excess Protein but Suboptimal Key Micronutrients and Essential Fatty Acids in the Intakes of Infants and Toddlers from Urban Settings in Malaysia.

This study determined the intakes of complementary foods (CFs) and milk-based formulas (MFs) by a total of 119 subjects aged 6-23.9 months from urban day care centers. Dietary intakes were assessed using two-day weighed food records. Intake adequacy of energy and nutrients was compared to the Recommended Nutrient Intakes (RNI) for Malaysia. The most commonly consumed CFs were cereals (rice, noodles, bread). The subjects derived approximately half of their energy requirements (kcals) from CFs (57 ± 35%) and MFs (56 ± 31%). Protein intake was in excess of their RNI requirements, from both CFs (145 ± 72%) and MFs (133 ± 88%). Main sources of protein included meat, dairy products, and western fast food. Intake of CFs provided less than the RNI requirements for vitamin A, thiamine, riboflavin, folate, vitamin C, calcium, iron, and zinc. Neither CF nor MF intake met the Adequate Intake (AI) requirements for essential fatty acids. These findings indicate imbalances in the dietary intake of the subjects that may have adverse health implications, including increased risk of rapid weight gain from excess protein intake, and linear growth faltering and intellectual impairment from multiple micronutrient deficiencies. Interventions are needed to improve child feeding knowledge and practices among parents and child care providers.

The effect of polyunsaturated fatty acid deficiency on allergic response in ovalbumin-immunized mice.

Polyunsaturated fatty acids (PUFAs) are present in biological membranes and influence membrane fluidity and immune responses. PUFAs such as 18:2n-6 and 18:3n-3 cannot be synthesized de novo in mammals and are thus called essential fatty acids (EFAs). In addition, PUFAs can be converted to very long-chain PUFAs (VLC-PUFAs), such as arachidonic acid and docosahexaenoic acid, in the body. Although avoiding allergens is an effective strategy for food-allergy patients, the dietary exclusion of several allergens reportedly induces deficiencies in essential nutrients such as PUFAs. In this study, we investigated whether an EFA-deficient (EFAD) diet influenced allergic symptoms in ovalbumin (OVA)-immunized mice. Unexpectedly, no exacerbation of immune responses after OVA-sensitization was observed in mice fed an EFAD diet, and no differences in serum PUFA levels between OVA-immunized and non-immunized mice fed the EFAD diet were detected. However, levels of VLC-PUFAs in the small intestine increased after OVA-sensitization and did not decrease during EFAD diet administration, showing that small intestinal VLC-PUFAs levels were strongly preserved in the food-allergy model mice. Further studies are required to elucidate the mechanisms by which small intestinal VLC-PUFAs are retained in food-allergy model mice.

Infant Essential Fatty Acid Status Is Not Associated With Postoperative Wound Complication Severity.

BACKGROUND: Neonates are susceptible to postoperative wound complications (POWCs), as prematurity, hypoxia, steroid use, immunosuppression, and malnutrition are all common comorbidities. Critically ill infants, dependent on parenteral nutrition, are at even further risk of developing essential fatty acid deficiency (EFAD). We hypothesized that POWC severity and EFAD were associated because of increased susceptibility to infections and impaired wound healing seen with EFAD. METHODS: Institutional review board-approved (OUHSC10554), retrospective review from our academic Level IV Neonatal Intensive Care Unit. Infants aged <1 y who underwent a fascial-compromising gastrointestinal surgery from June 1, 2015, to March 15, 2019, and who had essential fatty acids (EFAs) measured ±2 wk from surgery were included. Three blinded investigators independently categorized POWC using the World Union of Wound Healing Society Surgical Wound Grading System. Infants were categorized into three groups: no POWC, POWC Grades 1 and 2 (superficial tissue nonintegrity), and POWC Grades 3 and 4 (deep tissue nonintegrity and complete dehiscence). EFA status and other possible POWC-associated factors were analyzed to determine any association with wound severity. RESULTS: Fifty infants met the inclusion criteria. Half (25/50) had no POWC, 30% (15/50) had Grade 1 or 2, and 20% (10/50) had Grade 3 or 4. We found no association between EFAD and POWC severity. CONCLUSIONS: In our cohort, EFA status did not predict POWC severity. At this time, we cannot suggest delaying elective surgical procedures to correct EFAD as an approach to preventing POWC.

Plasma and Red Blood Cell PUFAs in Home Parenteral Nutrition Paediatric Patients-Effects of Lipid Emulsions.

Background: Mixed lipid emulsions (LE) containing fish oil present several advantages compared to the sole soybean oil LE, but little is known about the safety of essential fatty acids (EFA) profile in paediatric patients on long-term Parenteral Nutrition (PN). Aim of the study: to assess glycerophosfolipid polyunsaturated fatty acids (PUFA) levels on plasma and red blood cell (RBC) membrane of children on long term PN with composite LE containing fish oil (SMOF), and to compare it with a group receiving olive oil LE (Clinoleic®) and to the reference range for age, previously determined on a group of healthy children. Results: A total of 38 patients were enrolled, median age 5.56 (0.9-21.86) years, 15 receiving Clinoleic®, 23 receiving SMOF. Patients on SMOF showed significantly higher levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), lower levels of arachidonic acid (ARA) and Mead acid (MEAD)/ARA ratio in plasma and RBC compared with patients on Clinoleic® and with healthy children. Triene:tetraene (T:T) ratio of both groups of patients did not differ from that of healthy children-median plasma (MEAD/ARA: 0.01, interquartile rage (IQR) 0.01, p = 0.61 and 0.02, IQR 0.02, p = 0.6 in SMOF and Clinoleic® patients, respectively), and was considerably lower than Holman index (>0.21). SMOF patients showed no statistically significant differences in growth parameters compared with Clinoleic® patients. Patients of both groups showed stiffness class F0-F1 of liver stiffness measure (LSM) 5.6 (IQR 0.85) in SMOF patients and 5.3 (IQR 0.90) in Clinoleic® patients, p = 0.58), indicating absence of liver fibrosis. Conclusions: Fatty acids, measured as concentrations (mg/L), revealed specific PUFA profile of PN patients and could be an accurate method to evaluate nutritional status and eventually to detect essential fatty acid deficiency (EFAD). SMOF patients showed significantly higher EPA, DHA and lower ARA concentrations compared to Clinoleic® patients. Both LEs showed similar hepatic evolution and growth.

The Impact of Glucose-Based or Lipid-Based Total Parenteral Nutrition on the Free Fatty Acids Profile in Critically Ill Patients.

INTRODUCTION: Our study aim was to assess how the macronutrient intake during total parenteral nutrition (TPN) modulates plasma total free fatty acids (FFAs) levels and individual fatty acids in critically ill patients. METHOD: Adult patients aged 18-80, admitted to the intensive care unit (ICU), who were indicated for TPN, with an expected duration of more than three days, were included in the study. Isoenergetic and isonitrogenous TPN solutions were given with a major non-protein energy source, which was glucose (group G) or glucose and lipid emulsions (Smof lipid; group L). Blood samples were collected on days 0, 1, 3, 6, 9, 14, and 28. RESULTS: A significant decrease (p < 0.001) in total FFAs occurred in both groups with a bigger decrease in group G (p < 0.001) from day 0 (0.41 ± 0.19 mmol∙L-1) to day 28 (0.10 ± 0.07 mmol∙L-1). Increased palmitooleic acid and decreased linoleic and docosahexaenoic acids, with a trend of increased mead acid to arachidonic acid ratio, on day 28 were observed in group G in comparison with group L. Group G had an insignificant increase in leptin with no differences in the concentrations of vitamin E, triacylglycerides, and plasminogen activator inhibitor-1. CONCLUSION: Decreased plasma FFA in critically ill patients who receive TPN may result from increased insulin sensitivity with a better effect in group G, owing to higher insulin and glucose dosing and no lipid emulsions. It is advisable to include a lipid emulsion at the latest from three weeks of TPN to prevent essential fatty acid deficiency.

Essential fatty acids deficient diet modulates N-Acylethanolamide profile in rat's tissues.

No data are available on whether a diet deficient of the essential fatty acids is able to modulate tissue levels of endocannabinoids and congeners. Male rats fed for 12 weeks a diet deficient of essential fatty acids, palmitic and oleic acids (EFAD), replaced with saturated fatty acids (SAFA), showed lowered n-3 and n-6 PUFAs levels in plasma, liver and adipose tissue, with concomitant steep increase of oleic and mead acids, while in hypothalamus no changes in PUFA concentration were detected and only palmitoleic acid was found increased. We found a reduction of anandamide and palmitoylethanolamide in liver and brain, while oleoylethanolamide increased significantly in liver and adipose tissue, associated to a 50 % body weight decrease. Changes in N-acylethanolamide profile may contribute to body weight reduction distinctive of EFA deficiency.

Enhanced Triacylglycerol Content and Gene Expression for Triacylglycerol Metabolism, Acyl-Ceramide Synthesis, and Corneocyte Lipid Formation in the Epidermis of Borage Oil Fed Guinea Pigs.

Triacylglycerol (TAG) metabolism is related to the acyl-ceramide (Cer) synthesis and corneocyte lipid envelope (CLE) formation involved in maintaining the epidermal barrier. Prompted by the recovery of a disrupted epidermal barrier with dietary borage oil (BO: 40.9% linoleic acid (LNA) and 24.0% γ-linolenic acid (GLA)) in essential fatty acid (EFA) deficiency, lipidomic and transcriptome analyses and subsequent quantitative RT-PCR were performed to determine the effects of borage oil (BO) on TAG content and species, and the gene expression related to overall lipid metabolism. Dietary BO for 2 weeks in EFA-deficient guinea pigs increased the total TAG content, including the TAG species esterified LNA, GLA, and their C20 metabolized fatty acids. Moreover, the expression levels of genes in the monoacylglycerol and glycerol-3-phosphate pathways, two major pathways of TAG synthesis, increased, along with those of TAG lipase, acyl-Cer synthesis, and CLE formation. Dietary BO enhanced TAG content, the gene expression of TAG metabolism, acyl-Cer synthesis, and CLE formation.

Essential Fatty Acid Requirements and Intravenous Lipid Emulsions.

Linoleic acid (LA) and α-linolenic acid (ALA) must be supplied to the human body and are therefore considered essential fatty acids. This narrative review discusses the signs, symptoms, diagnosis, prevention, and treatment of essential fatty acid deficiency (EFAD). EFAD may occur in patients with conditions that severely limit the intake, digestion, absorption, and/or metabolism of fat. EFAD may be prevented in patients requiring parenteral nutrition by inclusion of an intravenous lipid emulsion (ILE) as a source of LA and ALA. Early ILEs consisted solely of soybean oil (SO), a good source of LA and ALA, but being rich in LA may promote the production of proinflammatory fatty acids. Subsequent ILE formulations replaced part of the SO with other fat sources to decrease the amount of proinflammatory fatty acids. Although rare, EFAD is diagnosed by an elevated triene:tetraene (T:T) ratio, which reflects increased metabolism of oleic acid to Mead acid in the absence of adequate LA and ALA. Assays for measuring fatty acids have improved over the years, and therefore it is necessary to take into account the particular assay used and its reference range when determining if the T:T ratio indicates EFAD. In patients with a high degree of suspicion for EFAD, obtaining a fatty acid profile may provide additional useful information for making a diagnosis of EFAD. In patients receiving an ILE, the T:T ratio and fatty acid profile should be interpreted in light of the fatty acid composition of the ILE to ensure accurate diagnosis of EFAD.

Intravenous Fish Oil and Serum Fatty Acid Profiles in Pediatric Patients With Intestinal Failure-Associated Liver Disease.

BACKGROUND: Intravenous fish oil (FO) treats pediatric intestinal failure-associated liver disease (IFALD). There are concerns that a lipid emulsion composed of ω-3 fatty acids will cause an essential fatty acid deficiency (EFAD). This study's objective was to quantify the risk for abnormal fatty acid concentrations in children treated with FO. METHODS: Inclusion criteria for this prospective study were children with intestinal failure. Intravenous soybean oil (SO) was replaced with FO for no longer than 6 months. Serum fatty acids were analyzed using linear and logistic models, and compared with age-based norms to determine the percentage of subjects with low and high concentrations. RESULTS: Subjects (n = 17) started receiving FO at a median of 3.6 months (interquartile range 2.4-9.6 months). Over time, α-linolenic, linoleic, arachidonic, and Mead acid decreased, whereas docosahexaenoic and eicosapentaenoic acid increased (P < 0.001 for all). Triene-tetraene ratios remained unchanged (P = 1). Although subjects were 1.8 times more likely to develop a low linoleic acid while receiving FO vs SO (95% CI: 1.4-2.3, P < 0.01), there was not a significant risk for low arachidonic acid. Subjects were 1.6 times more likely to develop high docosahexaenoic acid while receiving FO vs SO; however, this was not significant (95% CI: 0.9-2.6, P = 0.08). CONCLUSION: In this cohort of parenteral nutrition-dependent children, switching from SO to FO led to a decrease in essential fatty acid concentrations, but an EFAD was not evident. Low and high levels of fatty acids developed. Further investigation is needed to clarify if this is clinically significant.

Essential Fatty Acid Status in Surgical Infants Receiving Parenteral Nutrition With a Composite Lipid Emulsion: A Case Series.

Infants requiring prolonged parenteral nutrition (PN) may receive intravenous (IV) lipid in the form of soybean oil, fish oil, or a composite lipid emulsion (CLE) (i.e., SMOFlipid®). Soybean oil lipid-dose restriction is a popular method of treating and reducing the risk of intestinal failure-associated liver disease (IFALD) that may influence dosing strategies of other IV fat emulsions. Here we present 4 infants receiving PN with SMOFlipid® as their IV lipid source and examine trends in essential fatty-acid status, triglycerides, and dosing strategy. The infants on restricted doses of CLE developed biochemical essential fatty-acid deficiency (EFAD) that resolved with a dosage increase or by transition to a pure fish-oil lipid emulsion. Three of the 4 infants originally prescribed CLE were diagnosed with IFALD and started a pure fish-oil lipid emulsion after treatable causes of cholestasis were excluded. One of the 4 infants presented with hypertriglyceridemia that resolved upon transition to pure fish-oil lipid emulsion. Misapplication of lipid restriction protocols to CLE regimens render infants at risk for EFAD. CLE should be dosed within recommended ranges to prevent EFAD. Restricted protocols warrant close monitoring of essential fatty-acid status in infants receiving prolonged PN, particularly in those with minimal or no enteral intake. Hypertriglyceridemia and cholestasis are known adverse effects of CLE and require monitoring.

Essential Fatty Acid Deficiency with SMOFlipid Reduction in an Infant with Intestinal Failure-Associated Liver Disease.

Multicomponent lipid emulsions, such as SMOFlipid, contain intermediate amounts of essential fatty acids (EFAs) compared with traditional soybean-oil based lipid emulsions and 100% fish-oil lipid emulsions. We describe the development of moderate EFA deficiency (EFAD) and slow weight gain in an infant with intestinal failure-associated liver disease managed with SMOFlipid reduction (1 g/kg/d). Once SMOFlipid dosage was increased (2-3 g/kg/d), EFA levels normalized, adequate growth resumed, and the infant's cholestasis resolved. We recommend avoiding lipid reduction of SMOFlipid, which not only increases the risk for EFAD, but also is unnecessary given that cholestasis can be reversed on conventional doses of SMOFlipid.

Borage oil restores acidic skin pH by up-regulating the activity or expression of filaggrin and enzymes involved in epidermal lactate, free fatty acid, and acidic free amino acid metabolism in essential fatty acid-deficient Guinea pigs.

Borage oil (BO) reverses a disrupted epidermal lipid barrier and hyperproliferation in essential fatty acid deficiency (EFAD). However, little is known about its effect on skin pH, which is maintained by epidermal lactate, free fatty acids (FFAs), and free amino acids (FAAs) which is generated by lactate dehydrogenase (LDH), secreted phospholipase A2 (sPLA2), or filaggrin degradation with peptidylarginine deiminase-3 (PADI3). We hypothesized that BO restores skin pH by regulating epidermal lactate, FFA metabolism, or FAA metabolism in EFAD. To test this hypothesis, EFAD was induced in guinea pigs by a hydrogenated coconut oil (HCO) diet for 8 weeks, followed by 2 weeks of a BO diet (group HCO + BO). As controls, groups HCO and BO were fed HCO or BO diets for 10 weeks. In group HCO + BO, skin pH, which was less acidic in group HCO, was restored; and epidermal lactate and total FFAs, including palmitate, stearate, linoleate, arachidate, behenate, and lignocerate, were higher than in group HCO. LDH and sPLA2 (mainly the PLA2G2F isoform) activities and protein expressions were similar between groups HCO + BO and BO. Epidermal acidic FAAs, as well as filaggrin and PADI3 protein and mRNA expressions were higher in group HCO + BO than in group HCO. Oleate, total FAAs including other FAAs, and LDH and sPLA2 mRNA expressions were not altered between groups HCO and HCO + BO. Basic FAAs were not altered among groups. Dietary BO restored acidic skin pH and increased epidermal levels of lactate, most FFAs, and acidic FAAs by up-regulating LDH, sPLA2, filaggrin, and PADI3 activities as well as protein or mRNA expressions in EFAD.

Controversies in the Use of Lipid Injectable Emulsion in Hospitalized Patients.

Soybean oil-based lipid injectable emulsion (SO-based ILE) is an 18-carbon, ω-6 macronutrient providing a concentrated source of calories, which can be administered in or with parenteral nutrition to patients unable to tolerate or consume adequate enteral nutrition. Beyond the provision of energy, SO-based ILE provides linoleic and linolenic acid, 2 essential fatty acids necessary for the prevention of essential fatty acid deficiency. However, SO-based ILE with its high levels of ω-6 fatty acids, long-chain triglycerides, phospholipid emulsifiers, and glycerin has been associated with worsening clinical outcomes, including increase of infections, lengthier intensive care and hospital stay, and prolonged mechanical ventilation. Recognizing this, studies have investigated omitting SO-based ILE in the critically ill patient for the first 7 days to observe if clinical outcomes are improved. Unfortunately, there is extremely limited research, and what is available is controversial. National guidelines have analyzed the studies, and they too are challenged to define a clear, high quality of evidence recommendation. It is important for the healthcare clinician to understand the research around this controversy to make best decisions for their patients.

Children With Intestinal Failure Undergoing Intestinal Rehabilitation Are at Risk for Essential Fatty Acid Deficiency.

BACKGROUND: Essential fatty acid (EFA) status may be compromised during the intestinal failure (IF) rehabilitation. Parenteral lipid restriction is used to treat intestinal failure associated liver disease (IFALD), while the enteral fatty acid (FA) absorption remains limited. We analyzed the FA status among pediatric IF and intestinal insufficiency patients. METHODS: We evaluated 49 patients aged 0-18 years attending our nationwide IF referral center. Their serum FA fractions were determined and examined against previous nutrition, parenteral lipid emulsion, and intestinal anatomy data. The patients were divided into 3 subgroups according to their dependence on parenteral nutrition (PN): full enteral (EN) (n = 33), supplemental PN (n = 14) or predominantly PN (n = 20). Trien:tetraen ratio (TTR) ≥0.2 was considered diagnostic for essential fatty acid deficiency (EFAD) and increased risk was suspected if TTR exceeded 0.1. RESULTS: We identified 8 (16%) patients with elevated TTR ≥0.1; in 3 of them the ratio exceeded 0.2. Five of these children belonged to supplemental PN group. This group carried the highest incidence of elevated TTR (P = 0.0016), with median TTR at 0.06 (interquartile range 0.03-0.09) and two-thirds of the analyzed TTR ≥0.5. Increased EFAD risk was associated with young age (P = 0.0291), current PN with low parenteral lipid content (P = 0.0003), and short remaining small bowel (P = 0.0013). CONCLUSIONS: IF children with supplemental PN carry the highest overall risk for EFAD. Young age, current PN, and short remaining small bowel also increase the risk for EFAD.

Redefining essential fatty acids in the era of novel intravenous lipid emulsions.

The essentiality of fatty acids was determined by the Burrs in the 1920s. It is commonly accepted that provision of linoleic (LA) and alpha-linolenic acids (ALA) prevents and reverses essential fatty acid deficiency (EFAD). Development of alternative injectable lipid emulsions (ILE) low in LA and ALA has raised concern about their ability to prevent EFAD. This review provides biochemical evidence coupled with observations from animal and human studies that aim to characterize which fatty acids are truly essential to prevent EFAD. Retroconversion pathways and mobilization from body stores suggest that arachidonic and docosahexaenoic acids (ARA and DHA - the main derivatives of LA and ALA, respectively) also prevent EFAD. Our group first proposed the essentiality of ARA and DHA by feeding mice exclusively these fatty acids and proving that they prevent EFAD. Survival for 5 generations on this diet provides additional evidence that growth and reproductive capabilities are maintained. Moreover, the use of fish oil-based ILE, with minimal LA and ALA and abundant DHA and ARA, for treatment of intestinal failure-associated liver disease, does not result in EFAD. These findings challenge the essentiality of LA and ALA in the presence of ARA and DHA. Evidence discussed in this review supports the idea that ARA and DHA can independently fulfill dietary essential fatty acid requirements. The imminent introduction of new ILE rich in ARA and DHA in the United States highlights the importance of understanding their essentiality, especially when provision of ALA and LA is below the established daily minimum requirement.