Translating plasma citrulline concentration in clinical practice: Role of cross-sectional assessment in adult patients with short bowel syndrome.

BACKGROUND: Cross-sectional plasma citrulline concentration (CIT) is considered a marker of enterocyte mass. The role of CIT in clinical practice in patients with short bowel syndrome (SBS) is not clearly defined. AIM: To assess the accuracy of CIT to discriminate SBS from healthy controls (HC) and SBS with intestinal failure (SBS-IF), requiring intravenous supplementation (IVS), from SBS with intestinal insufficiency (SBS-II). METHODS: Cross-sectional study on unselected outpatients (31 SBS-II, 113 SBS-IF) and 19 healthy controls (HC). Demographic data, SBS characteristics, nutritional status, oral intake, intestinal fat absorption, renal function and IF severity, categorized by the volume of the required IVS, were collected at time of CIT evaluation (µmol/L). Data as mean±SD. RESULTS: CIT was 36.6 ± 6.0 in HC, 30.2 ± 14.0 in SBS-II and 18.8 ± 12.3 in SBS-IF (p < 0.001). CIT cutoff was 31 for the diagnosis of SBS (sensitivity 79 %, specificity 89 %), and 14 for the discrimination between SBS-IF and SBS-II (sensitivity 100 %, specificity 51 %). Wide ranges of CIT were observed in all SBS-IF severity categories. CONCLUSIONS: In unselected SBS patients, CIT was accurate to diagnose SBS, had high sensitivity to diagnose SBS-IF but showed low specificity for SBS-II. In SBS-IF, CIT was not an accurate marker of IF severity.

The gut microbiota in adults with chronic intestinal failure.

OBJECTIVE: Fecal microbiota was investigated in adult patients with chronic intestinal failure (CIF) due to short bowel syndrome (SBS) with jejunocolonic anastomosis (SBS-2). Few or no data are available on SBS with jejunostomy (SBS-1) and CIF due to intestinal dysmotility (DYS) or mucosal disease (MD). We profiled the fecal microbiota of various pathophysiological mechanisms of CIF. METHODS: Cross-sectional study on 61 adults with CIF (SBS-1 30, SBS-2 17, DYS 8, MD 6). Fecal samples were collected and profiled by 16S rRNA amplicon sequencing. Healthy controls (HC) were selected from pre-existing cohorts, matched with patients by sex and age. RESULTS: Compared to HC, SBS-1, SBS-2 and MD patients showed lower alpha diversity; no difference was found for DYS. In beta diversity analysis, SBS-1, SBS-2 and DYS groups segregated from HC and from each other. Taxonomically, the CIF groups differed from HC even at the phylum level. In particular, CIF patients' microbiota was dominated by Lactobacillaceae and Enterobacteriaceae, while depleted in typical health-associated taxa belonging to Lachnospiraceae and Ruminococcaceae. Notably, compositional peculiarities of the CIF groups emerged. Furthermore, in the SBS groups, the microbiota profile differed according to the amount of parenteral nutrition required and the duration of CIF. CONCLUSIONS: CIF patients showed marked intestinal dysbiosis with microbial signatures specific to the pathophysiological mechanism of CIF as well as to the severity and duration of SBS.

Non-interventional, 5-year retrospective data of home parenteral nutrition in patients with benign chronic intestinal failure: Analysis of an Italian nurse registry (SERECARE II).

OBJECTIVE: This study is an assessment of home parenteral nutrition service performance and safety and efficacy outcomes in patients with benign chronic intestinal failure. METHODS: This is a retrospective, non-interventional, and multicenter study. Data were collected by trained nurses and recorded in a dedicated registry (SERECARE). RESULTS: From January 1, 2013 to June 30, 2018, data from a total of 683 patients with benign chronic intestinal failure were entered in the registry. Patients included 208 pediatric (53.8% male; median age = 4.0 y) and 475 adult (47.6% male; median age = 59.0 y) participants. On average, patients were visited 5.4 ± 4.5 times and received 1.4 ± 0.8 training sessions. Retraining was not common and mostly due to change of therapy or change of caregiver. Of 939 complications, 40.9% were related to the central venous catheter and were mostly infectious (n = 182) and mechanical (n = 187). The rate of infectious and mechanical complications per 1000 catheter days decreased over 5 y (0.30-0.15 and 0.33 -0.19, respectively). The rate of complications per 1000 catheter days and the mean complications per patient were higher in pediatric than in adult patients. The hospitalization rate was 1.01 per patient throughout the study period. These data were similar to those registered in a previous study period (2002-2011) (n = 1.53 per patient). Changes over time in the efficacy variables were mostly small and non-significant. CONCLUSIONS: This study confirms the importance of setting up and maintaining structured registries to monitor and improve home parenteral nutrition care. Safety outcomes have improved over the years, most likely due to the underlying efficient nursing service.

Candidacy of adult patients with short bowel syndrome for treatment with glucagon-like peptide-2 analogues: A systematic analysis of a single centre cohort.

BACKGROUND AND AIMS: The glucagon-like peptide-2 (GLP-2) analogue, teduglutide, allows to reduce the intravenous supplementation (IVS) dependency of patients with short bowel syndrome and intestinal failure (SBS-IF). The rate of candidacy of SBS-IF patients for the treatment is unknown. The candidacy for teduglutide treatment of our patient cohort was investigated by a systematic analysis. METHODS: The indications, contraindications, special warnings and precautions for use of teduglutide, listed in the drug monographs and in the phase-III trial protocol were adopted to categorize the patients as non-candidates (NC), potential candidates (PC) or straight candidates (SC) for the treatment. All the SBS-IF adult patients who were cured at our centre were assessed according to their clinical status on January 1st, 2020. RESULTS: Seventy-nine patients were evaluated: 34.2% were NC due to risk of digestive malignancy, recent history of any other cancer, or listing for intestinal transplantation; 30.4% were PC, because of other premalignant conditions, risk of intestinal obstruction, entero-cutaneous fistulas, or severe co-morbidities; 35.4% were SC. The SC group showed the lowest requirement of IVS: the lowest number of days of infusion per week (p = 0.0054), the lowest amount of energy (p = 0.0110) and volume (p = 0.0136). CONCLUSIONS: This systematic analysis allowed a pragmatic categorization of the candidacy of patients with SBS-IF for GLP-2 analogue treatment. The SC group appeared to have the highest probability of a successful response to the treatment. A systematic analysis of SBS-IF patient candidate for GLP-2 analogue therapy would allow a homogeneous patient selection and facilitate the worldwide comparison of the results of clinical practice and research.

Outcome of kidney function in adults on long-term home parenteral nutrition for chronic intestinal failure.

OBJECTIVE: The aim of this study was to evaluate kidney function outcome in adults on home parenteral nutrition (HPN) for chronic intestinal failure using the newly recommended equations for estimated glomerular filtration rate (eGFR) assessment in clinical practice. METHODS: This was an observational study with 72 patients. Clinical and biochemical parameters were collected at initiation of HPN (retrospective baseline [BL]), at inclusion in the study (cross-sectional [CS]), and at the end of a 30-mo prospective follow-up (Fup). The eGFR (mL/min/1.73 m2 body surface) was calculated by the Chronic Kidney Disease Epidemiology Collaboration creatinine and categorized as normal, mildly decreased (MDKF), and chronic kidney disease (CKD) when ≥90, 60 to 89, and <60, respectively. RESULTS: An eGFR<90 was observed in 41.7% of patients at BL, 53.4% at CS, and 56.6% at Fup. A CKD was present in all of the patients at BL, 20.1% at CS, and 35.9% at Fup. The probability of maintaining an eGFR ≥60 was 98%, 82%, and 79% at 1, 5, and 10 y after BL, respectively (Kaplan-Meier analysis). The probability was lower in patients with MDKF at BL (P = 0.039). The development of a CKD was significantly associated with aging and urologic diseases and numerically associated with the episodes of venous-catheter sepsis, short bowel syndrome, and a low volume of HPN. CONCLUSIONS: In patients on HPN for chronic intestinal failure, decreased kidney function is a frequent finding, even at HPN commencement, demanding accurate monitoring during the treatment. Prevention of CKD primarily relies on the maintenance of fluid balance and the prevention of catheter-sepsis and urologic diseases.

Assessment of Intestinal Failure Associated Liver Disease according to different diagnostic criteria.

BACKGROUND & AIMS: Intestinal failure associated liver disease (IFALD) has been defined using numerous criteria; however the clinical relevance of these criteria has never been compared. We therefore aimed to evaluate the prevalence, incidence, evolution of IFALD diagnosed by different criteria and to assess any clinical features that may be associated with its occurrence. METHODS: A cross sectional (CS) and retrospective study were carried out on adults on home parenteral nutrition (HPN) for chronic intestinal failure (CIF) managed at a single center. Inclusion criteria at CS: age ≥18 years, benign disease. Collected data included: patient demographics, CIF and HPN characteristics, episodes of central venous catheter related bloodstream infection (CRBSI). IFALD was diagnosed by 9 criteria based on liver function tests and liver ultrasound (US) imaging. IFALD diagnoses were categorized as steatosis (2 criteria), cholestasis (3 criteria) or fibrosis (2 criteria) and unclassified (2 criteria). Prevalence was assessed at CS and at starting HPN (baseline, BS). Evolution was assessed as change of IFALD between BS and CS. Incidence was calculated as patients who developed IFALD from BS to CS. RESULTS: A total of 113 patients were included. At CS, IFALD prevalence range in each diagnostic categories was: cholestasis 5-15%; steatosis 17-43%; fibrosis 10-20%; unclassified 7-38%. A 28.5% of patients did not have IFALD according to any criteria. Two cholestasis criteria and one fibrosis criterion were significantly (P < 0.05) associated with a short bowel syndrome as the pathophysiological mechanism of CIF, HPN requirement and the number of CRBSI episodes. At BS, IFALD prevalence range was: cholestasis 13-40%; steatosis 27-90%; fibrosis 2-5%; unclassified 8-75%. The incidence range of IFALD was: cholestasis 0-7%; steatosis 0-39%; fibrosis 7-18%; unclassified 4-9%. IFALD steatosis diagnosed by US was the most frequent diagnosis at both CS prevalence and incidence assessments. Notably, IFALD criteria normalized in various percentages (2-70%), depending on the diagnostic categories, between BS and CS. CONCLUSIONS: This is the first study to systematically demonstrate that the frequency of IFALD varies greatly depending on diagnostic criteria used, confirming the need for a consensus definition to be used between different national and international IF units. IFALD can be present at HPN initiation but may resolve thereafter; further work is required to evaluate the factors associated with improvement.

Functional lipidomics in patients on home parenteral nutrition: Effect of lipid emulsions.

AIM: To investigate the fatty acid-based functional lipidomics of patients on long-term home parenteral nutrition receiving different intravenous lipid emulsions. METHODS: A cross-sectional comparative study was carried out on 3 groups of adults on home parenteral nutrition (HPN), receiving an HPN admixture containing an olive-soybean oil-based intravenous lipid emulsion (IVLE) (OO-IVLE; n = 15), a soybean- medium-chain triacylglycerol-olive-fish oil-based IVLE (SMOF-IVLE; n = 8) or HPN without IVLE (No-IVLE; n = 8) and 42 healthy controls (HCs). The inclusion criteria were: duration of HPN ≥ 3 mo, current HPN admixtures ≥ 2 mo and HPN infusions ≥ 2/wk. Blood samples were drawn 4-6 h after the discontinuation of the overnight HPN infusion. The functional lipidomics panel included: the red blood cell (RBC) fatty acid (FA) profile, molecular biomarkers [membrane fluidity: saturated/monounsaturated FA ratio = saturated fatty acid (SFA)/monounsaturated fatty acid (MUFA) index; inflammatory risk: n-6/n-3 polyunsaturated fatty acid (PUFA) ratio = n-6/n-3 index; cardiovascular risk: sum of n-3 eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) = n-3 index; free radical stress: sum of FA trans isomers = %trans index] and FA pathway enzyme activity estimate (delta-9-desaturase = D9D; delta-6-desaturase = D6D; delta-5-desaturase = D5D; elongase = ELO). Statistics were carried out using nonparametric tests. The amount of each FA was calculated as a percentage of the total FA content (relative%). RESULTS: In the OO-IVLE group, the percentage of oleic acid in the RBCs was positively correlated with the weekly load of OO-IVLE (r = 0.540, P = 0.043). In the SMOF-IVLE cohort, the RBC membrane EPA and DHA were positively correlated with the daily amount of SMOF-IVLE (r = 0.751, P = 0.044) and the number of HPN infusions per week (r = 0.753; P = 0.046), respectively. The SMOF-IVLE group showed the highest EPA and DHA and the lowest arachidonic acid percentages (P < 0.001). The RBC membrane linoleic acid content was lower, and oleic and vaccenic acids were higher in all the HPN groups in comparison to the HCs. Vaccenic acid was positively correlated with the weekly HPN load of glucose in both the OO-IVLE (r = 0.716; P = 0.007) and the SMOF-IVLE (r = 0.732; P = 0.053) groups. The estimated activity of D9D was higher in all the HPN groups than in the HCs (P < 0.001). The estimated activity of D5D was lower in the SMOF-IVLE group than in the HCs (P = 0.013). The SFA/MUFA ratio was lower in all the HPN groups than in the HCs (P < 0.001). The n-6/n-3 index was lower and the n-3 index was higher in the SMOF-IVLE group in comparison to the HCs and to the other HPN groups (P < 0.001). The %trans index did not differ among the four groups. CONCLUSION: The FA profile of IVLEs significantly influenced the cell membrane functional lipidomics. The amount of glucose in the HPN may play a relevant role, mediated by the insulin regulation of the FA pathway enzyme activities.

Plasma citrulline after small bowel transplantation: effect of time from transplantation, acute cellular rejection, and renal failure.

BACKGROUND: Plasma citrulline concentration (CIT) depends on its synthesis by enterocytes and its catabolism by renal tubules. To evaluate CIT applicability as a marker of acute cellular rejection (ACR) after intestinal transplantation (ITx), CIT was investigated according to time from ITx, episodes of ACR, and creatinine clearance (CrCl). METHODS: Twenty-four adult ITx recipients were prospectively studied. The results were compared with those of 19 healthy controls (HCs) and of 29 patients with chronic renal failure (CRF). RESULTS: In ITx recipients, CIT was lower than in HCs during the first two postoperative weeks; it then progressively increased and reached the range observed in HCs, approximately between the 31st and the 45th postoperative day. A positive association with postoperative days (R = 0.63; p < 0.0001) and a negative association with CrCl (R = -0.57; p < 0.0001) were observed. CIT was higher in patients with CRF than in HCs (p < 0.0001). CIT sensitivity and specificity in detecting ACR after the 45th postoperative day were 38% and 83%, using CIT threshold observed in HCs, and 69% and 77%, respectively, using CIT threshold adjusted for CRF degree. CONCLUSIONS: Adjusting CIT threshold for CRF degree almost doubled the sensitivity of CIT as a non-invasive marker of ACR in ITx recipients.

Iodine status in intestinal failure in adults.

PURPOSE OF REVIEW: The aim of this work is to review the recent findings on iodine nutrition in adults with intestinal failure. RECENT FINDINGS: Patients with intestinal failure who require long-term parenteral nutrition are potentially at risk for trace element deficiencies. It was considered that iodine deficiency was unlikely to occur in adults on parenteral nutrition, even if iodine is not added to parenteral nutrition, because of iodine absorption from iodine-containing antiseptics, to presence of iodine as contaminant in parenteral nutrition products and to absorption of dietary iodine, in patients eating and having a functioning duodenum. It is believed that thyroidal iodine could support thyroid function for several months during total parenteral nutrition. Clinical Nutrition Societies do not have uniform opinion about the need to supplement iodine routinely in parenteral nutrition in adults. Although very few studies have addressed this topic, inadequate iodine supply in long-term parenteral nutrition in young adults, and the increased risk of iodine deficiency in adults on long-term parenteral nutrition have recently been reported. SUMMARY: There is some evidence that adults with intestinal failure on long-term parenteral nutrition may be at risk of iodine deficiency. Studies carried out in large cohorts of patients are required to better define iodine requirements in long-term parenteral nutrition.

Intravenous lipids in home parenteral nutrition.

Intravenous lipid emulsions (IVLEs) are an important component of the nutritional admixtures for patients on long-term home parenteral nutrition (HPN) for chronic intestinal failure (CIF). IVLEs are primarily used as a source of energy and essential fatty acids, and the content of polyunsaturated fatty acids (PUFAs) is the most important characteristic of IVLEs. IVLEs rich in n-6 PUFAs may have a pro-inflammatory effect, whereas those rich in n-3 PUFAs may exert an anti-inflammatory effect. Other components to be considered are the risk of lipid peroxidation and the contents of α-tocopherol and phytosterols. Published studies were reviewed to determine the effects of the commercially available IVLEs on essential fatty acid status, liver function tests, lipid peroxidation and inflammatory indices, and α-tocopherol status, as well as their clinical safety and efficacy in patients on HPN. Investigations on the efficacy of fish oil-based IVLEs, which are rich in n-3 PUFAs, in the treatment of parenteral nutrition-associated liver disease (PNALD) in adult patients on HPN for CIF were also analyzed. The current commercial IVLE formulations have similar clinical safety profiles and efficacies and can prevent the development of essential fatty acid deficiency in adults on HPN for CIF. IVLE with a low content of n-6 PUFAs and with or without increased n-3 PUFA content may reduce the risk of PNALD. Fish oil-based IVLE, which is rich in n-3 PUFAs, may be effective in reversing hepatic cholestasis due to PNALD.

Iodine nutrition in adults on long-term home parenteral nutrition.

OBJECTIVE: The aim of this study was to evaluate iodine nutrition in adults on long-term home parenteral nutrition (HPN) and to compare it with iodine supplemented with PN, categorized as below or according to the European Society for Clinical Nutrition and Metabolism guidelines (ESPEN-GL) recommendation. METHODS: Iodine nutrition was evaluated retrospectively in 31 stable adults on long-term HPN. We analyzed urinary iodine concentration (UIC) and serum thyroid-stimulating hormone (TSH). A median UIC value ≥100 µg/L was considered indicative of adequate iodine intake, a value between 50 and 100 was indicative of moderate iodine deficiency, and a value <50 µg/L was indicative of overt iodine deficiency. RESULTS: PN iodine amount was according to ESPEN-GL in 26% of patients and lower in 19%; 55% did not receive iodine with PN. The median UIC was 63 µg/L (95% confidence interval [CI], 26-99 µg/L) in the whole group of patients, 56 µg/L (95% CI, 24-100) in the group including patients who did not receive any PN iodine supplementation and those who received PN iodine supply lower than the ESPEN-GL recommendation, and slightly higher (77 µg/L) in eight patients with PN iodine supply according to the ESPEN-GL (P = 0.42). TSH was normal in 74% of patients, increased in 23%, and reduced in 3%. Results did not change when patients with reduced glomerular filtration rate were excluded from the analysis. CONCLUSIONS: The analyzed patients on long-term HPN had a low iodine intake as shown by low median UIC level, as did the group of patients who received PN iodine supplementation according to ESPEN-GL. A condition of subclinical hypothyroidism was observed in a small percentage of patients.

Renal function in patients on long-term home parenteral nutrition and in intestinal transplant recipients.

OBJECTIVE: A decrease of renal function was described in patients on long-term home parenteral nutrition (HPN) for benign intestinal failure. The risk for chronic renal failure (CRF) due to frequent episodes of dehydration despite optimal HPN, is an indication for intestinal transplantation (ITx). ITx is the solid organ transplant at highest risk for developing CRF. The aim of this study was to compare the prevalence and the probability of CRF occurring in adults on HPN and after ITx. METHODS: A cross-sectional and retrospective follow-up study was carried out in 2011. Renal function was evaluated at cross-sectional and at time of starting HPN or ITx, by serum creatinine concentration (mg/dL) and estimated glomerular filtration rate (eGFR), according to the Modification of Diet in Renal Disease equation (mL·min·1.73 m2). CRF was defined as eGFR <60. Duration of follow up was from time of starting treatment to time of cross-sectional. RESULTS: We enrolled 33 patients on HPN and 22 who had undergone ITx. The frequency of CRF was 6% in the HPN group and 9% in the ITx group (P = 0.67) at start of treatment, and 21% and 54%, respectively (P = 0.01) at the time of the cross-sectional evaluation. During the follow-up, the annual decline of eGFR was 2.8% and 14.5%, respectively (P = 0.02). The 5-y probability of maintaining an eGFR ≥60 was 84% in the HPN group and 44% in the ITx group (P < 0.001). CONCLUSIONS: The decrease of renal function and the risk for developing CRF are greater after ITx than during HPN. The risk for CRF on HPN, as a criterion for ITx, should be revised.

The complex relationship between magnesium and serum parathyroid hormone: a study in patients with chronic intestinal failure.

In this study we compared the content of muscle free [Mg2+] assessed by 31P MRS to that of serum total Mg assessed by routine colorimetric assays in 15 patients affected by Chronic Intestinal Failure (CIF) on long-term Home Parenteral Nutrition (HPN) or who had undergone isolated intestinal transplantation. We also investigated in the same cohort of patients the relationship of muscle free [Mg2+] and serum total Mg with parathyroid hormone (PTH) serum content. All patients showed a normal cytosolic free [Mg2+] in the calf muscle despite about half of them having a content of total serum [Mg] below or at the lower edge of the boundary limits. Muscle free Mg2+ and serum total Mg displayed an opposite correlation versus serum PTH, showing that the intracellular free form possesses a different functional metabolic meaning in the regulation of PTH secretion.

[Home parenteral nutrition and intestinal transplantation in the intestinal failure]. / Ruolo della nutrizione parenterale domiciliare e del trapianto di intestino nella insufficienza intestinale cronica benigna.

Home parenteral nutrition is the primary treatment for intestinal failure. Intestinal transplantation is indicated when home parenteral nutrition fails or when there is a risk of death because of underlying disease. Survival after transplantation is related to the appropriateness of the indication and the timing of listing for transplantation.

Vitamin A and vitamin E isoforms stability and peroxidation potential of all-in-one admixtures for parenteral nutrition.

BACKGROUND: In all-in-one admixtures (AIOs), vitamins can be degraded and lipid can be peroxidized by light exposure, oxygen action, and multiple chemical interactions. AIM: We investigated the impact of three commercial lipid emulsions and two multivitamin preparations on vitamin A and vitamin E chemical stability and lipid peroxidation potential of AIOs. METHODS: A soybean oil (Soy), soybean/medium-chain triacylglycerol oil (MCT), and olive/soybean oil (Olive)-based emulsion (all 20%), and a lyophilized (Lyo) and emulsified (Emu) multivitamin compounds, were tested. Two AIOs for each lipid emulsion were prepared, the former with Lyo and the latter with Emu. The concentrations of retinol palmitate, alpha-gamma-delta-tocopherol, and malondialdehyde were analyzed in AIOs, immediately (T0) and 24 hours (T24) after compounding. RESULTS: Retinol palmitate, and alpha- and gamma-tocopherol were more stable in MCT-AIOs than in both Soy-AIOs and Olive-AIOs (p < 0.013; p < 0.001 respectively). Furthermore alpha-tocopherol was more stable in Lyo-AIOs than in Emu-AIOs (p < 0.004). Malondialdehyde (MDA) increased differently among the admixtures; however the concentrations were similar in all AIOs at T24. CONCLUSIONS: The differences in retinol palmitate stability were due both to lipid emulsions per se and to interaction between lipid emulsions and multivitamin preparations. The alpha-gamma-tocopherol stability depended on both lipid emulsions and multivitamin preparations. In tested AIOs there was a different degradation rate of fat-soluble vitamins to keep the same lipid peroxidation level, since MDA concentrations at T24 were similar among AIOs.

Endogenous ethanol production in a patient with chronic intestinal pseudo-obstruction and small intestinal bacterial overgrowth.

The case of the gastrointestinal production of ethanol from Candida albicans and Saccharomyces cerevisiae in a Caucasian man with chronic intestinal pseudo-obstruction is reported. The patient, who declared to have always abstained from alcohol, was hospitalized for abdominal pain, belching and mental confusion. The laboratory findings showed the presence of ethanol in the blood. Gastric juice and faecal microbiological cultures were positive for C. albicans and S. cerevisiae. At home, he was on oral antibiotic therapy with amoxicillin plus clavulanic acid for a small bowel bacterial overgrowth, associated with a simple sugar-rich diet. Twenty-four hours after stopping both the antibiotic therapy and the simple sugar-rich diet, the blood ethanol disappeared. A provocative test, performed by giving amoxicillin plus clavulanic acid associated with the simple sugar-rich diet was followed by the reappearance of ethanol in the blood. A review of the literature is reported.

Peroxidation potential of lipid emulsions after compounding in all-in-one solutions.

OBJECTIVES: We investigated the peroxidation potential of fat emulsions in all-in-one solutions (AIOs). METHODS: Three 20% emulsions were compared: soybean oil (SO; 60% polyunsaturated fatty acids [PUFAs], alpha-tocopherol:PUFAs = 0.44), soybean plus medium-chain triacylglycerol (SO-MCT; 31% PUFAs, alpha-tocopherol:PUFAs = 0.35), and olive oil (OO; 21% PUFAs, alpha-tocopherol:PUFAs = 1.42). For each emulsion, six AIO solutions were prepared by adding 250 mL of emulsion to a lipid-free solution. Lipid peroxide (LPX) and malondialdehyde (MDA) concentrations were evaluated in fat emulsions, lipid-free solutions, and AIOs immediately (T0) and 24 h (T24) after lipid addition. Statistical analysis was done with analysis of variance. RESULTS: Fat emulsion LPX in SO-MCT was lower than that in SO (P = 0.015) and OO (P = 0.024); LPX in SO was greater than that in OO (P = 0.013); MDA in SO was greater than that in SO-MCT (P = 0.001) and OO (P = 0.013); and MDA in SO-MCT was greater than that in OO (P = 0.001). In comparison with MDA at AIO-T0, MDA at AIO-T24 increased in SO (P = 0.005) and SO-MCT (P < 0.001) and decreased in OO (P = 0.003); at AIO-T24, LPX was greater in SO, but not significantly. CONCLUSIONS: In AIO bags, LPX occurred within 24 h after the addition of the lipid emulsion and seemed to be directly related to the PUFA content and inversely related to the alpha-tocopherol:PUFA ratio of the emulsion.