Genome-wide association study and meta-analysis of phytosterols identifies a novel locus for serum levels of campesterol.

Sitosterolemia is a rare inherited disorder caused by mutations in the ABCG5/ABCG8 genes. These genes encode proteins involved in the transport of plant sterols. Mutations in these genes lead to decreased excretion of phytosterols, which can accumulate in the body and lead to a variety of health problems, including premature coronary artery disease. We conducted the first genome-wide association study (GWAS) in the Middle East/North Africa population to identify genetic determinants of plant sterol levels in Qatari people. GWAS was performed on serum levels of ß-sitosterol and campesterol using the Metabolon platform from Qatar Biobank (QBB) and genome sequence data provided by Qatar Genome Program. A trans-ancestry meta-analysis of data from our Qatari cohort with summary statistics from a previously published large cohort (9758 subjects) of European ancestry was conducted. Using conditional analysis, we identified two independent single nucleotide polymorphisms associated with ß-sitosterol (rs145164937 and rs4299376), and two others with campesterol (rs7598542 and rs75901165) in the Qatari population in addition to previously reported variants. All of them map to the ABCG5/8 locus except rs75901165 which is located within the Intraflagellar Transport 43 (IFT43) gene. The meta-analysis replicated most of the reported variants, and our study provided significant support for the association of variants in SCARB1 and ABO with sitosterolemia. Evaluation of a polygenic risk score devised from European GWAS data showed moderate performance when applied to QBB (adjusted-R2 = 0.082). These findings provide new insights into the genetic architecture of phytosterol metabolism while showing the importance including under-represented populations in future GWAS studies.

Characterization of faecal microbiota and serum inflammatory markers in dogs diagnosed with chronic enteropathy or small-cell lymphoma: a pilot study.

Dogs diagnosed with chronic enteropathy (CE) or small-cell lymphoma (SCL) exhibit marked differences in faecal microbiota and organic acid profiles compared with healthy dogs, as well as immune abnormalities in intestinal mucosal tissue. However, few studies have analysed trace organic acids, such as succinic acid, which have been suggested to be associated with IBD in humans. Therefore, in this study, we compared the faecal microbiota and organic acid profiles as well as serum inflammatory markers between dogs with disease (n = 11; 6 with CE and 5 with SCL) and healthy controls (n = 16). We also performed machine learning and correlation analysis to obtain more detailed insights into the characteristics of affected dogs. These results revealed that dogs with CE and SCL had lower levels of Erysipelotrichaceae (e.g. Turicibacter and Allobaculum), exhibited abnormalities in the succinic acid metabolism (i.e. succinic acid accumulation and decreased levels of Phascolarctobacterium as succinic acid-utilising bacteria) and increased levels of pathobiont bacteria such as Escherichia-Shigella. Additionally, the presence of Dubosiella was significantly negatively correlated with Canine Inflammatory Bowel Disease Activity Index scores. These findings are expected to aid the development of microbiome-based medications and/or supplements, although further verification is needed.

Dried blood spot-based free sterol signatures in sitosterolemia diagnostics.

BACKGROUND: Sitosterolemia is a rare inherited lipid metabolic disorder characterized by increased levels of plant sterols and accelerated atherosclerosis. Although early detection is beneficial for the prevention of disease progression, it is largely underdiagnosed by routine screening based on conventional lipid profiles. MATERIALS AND METHODS: A gas chromatography-mass spectrometry (GC-MS)-based profiling has been developed and validated to measure the levels of biologically active free sterols, including five endogenous sterols and three plant sterols (sitosterol, campesterol, and stigmasterol) in dried blood spot (DBS). RESULTS: Within- and between-run precisions were 1.4-11.1 % and 2.2-14.1 %, respectively, while the accuracies were all 86.3 âˆ¼ 121.9 % with the correlation coefficients (r2) > 0.988 for all the sterols. In the patients (four girls and two boys, 6.5 ± 2.8 years), sitosterol levels were significantly increased, with an optimal cut-off value of 2.5 µg/mL distinguishing them from ninety-three age-matched healthy children. A cut-off value of 31.9 µg/mL differentiated the patients from six ABCG5/ABCG8 heterozygous carriers. In addition, the molecular ratios of sitosterol to cholesterol, desmosterol, and 7-dehydrocholesterol provided excellent cut-off values of 26.3, 67.6, and 21.6, respectively, to distinguish patients from both healthy controls and heterozygous carriers. CONCLUSIONS: The novel DBS-based GC-MS profiling of free sterols accurately identified patients with sitosterolemia, with a performance comparable to that of a serum assay. The DBS profiling could be more feasible method in clinical practice as well as population screening programs, and it can provide diagnostic cut-off values for individual plant sterols.

Evaluation of the relationship between plasma glucagon-like peptide-2 and gastrointestinal dysbiosis in canine chronic enteropathies.

Chronic enteropathies are a common cause of morbidity in dogs and are associated with disruption of the normal gastrointestinal mucosal barrier. The objective of this prospective study was to determine the association between measures of gastrointestinal dysbiosis and plasma concentrations of glucagon-like peptide-2, a hormone responsible for normal mucosal structure, in dogs with chronic enteropathies. Fecal 16S V4 rRNA gene sequencing and quantitative PCR via the dysbiosis index was performed on 16 healthy controls and 18 dogs with chronic enteropathy prior to and 1 month after initiation of individualized therapy. Fasting and post-prandial plasma GLP-2 concentrations were measured via ELISA in healthy dogs and chronic enteropathy dogs at both time points. Alpha and beta diversity indices, as well as bacterial population abundances were compared between groups and time-points. Principal component analysis combined with least squares regression was used to identify taxa contributing to glucagon-like peptide-2 variance among groups. While the dysbiosis index did not differ between healthy dogs and dogs with chronic enteropathy, 16S V4 genomic sequencing identified 47 operational taxonomic units that differed between the groups, all but 2 of which resolved following chronic enteropathy treatment. Principal component analysis identified 6 families and 19 genera that contributed to differences in glucagon-like peptide-2 concentrations between groups. Dysbiosis associated with chronic enteropathies in dogs may contribute to the observed lower plasma glucagon-like peptide-2 concentrations. Further research into mechanisms of microbiota impact on the enteroendocrine system is needed. Association between glucagon-like peptide-2 secretion and microbiome indices may help to guide research into future treatment strategies for dogs with chronic enteropathy.

Platelet proteomic profiling in sitosterolemia suggests thrombocytopenia is driven by lipid disorder and not platelet aberrations.

ABSTRACT: Sitosterolemia is a rare autosomal recessive genetic disorder in which patients develop hypercholesterolemia and may exhibit abnormal hematologic and/or liver test results. In this disease, dysfunction of either ABCG5 or ABCG8 results in the intestinal hyperabsorption of all sterols, including cholesterol and, more specifically, plant sterols or xenosterols, as well as in the impaired ability to excrete xenosterols into the bile. It remains unknown how and why some patients develop hematologic abnormalities. Only a few unrelated patients with hematologic abnormalities at the time of diagnosis have been reported. Here, we report on 2 unrelated pedigrees who were believed to have chronic immune thrombocytopenia as their most prominent feature. Both consanguineous families showed recessive gene variants in ABCG5, which were associated with the disease by in silico protein structure analysis and clinical segregation. Hepatosplenomegaly was absent. Thrombopoietin levels and megakaryocyte numbers in the bone marrow were normal. Metabolic analysis confirmed the presence of strongly elevated plasma levels of xenosterols. Potential platelet proteomic aberrations were longitudinally assessed following dietary restrictions combined with administration of the sterol absorption inhibitor ezetimibe. No significant effects on platelet protein content before and after the onset of treatment were demonstrated. Although we cannot exclude that lipotoxicity has a direct and platelet-specific impact in patients with sitosterolemia, our data suggest that thrombocytopenia is neither caused by a lack of megakaryocytes nor driven by proteomic aberrations in the platelets themselves.

The effects of different parenteral nutrition lipid formulations on clinical and laboratory endpoints in patients receiving home parenteral nutrition: A systematic review.

BACKGROUND: Home parenteral nutrition (HPN) is a life-sustaining therapy for individuals with intestinal failure in a community setting. It refers to the intravenous infusion of macronutrients, micronutrients, fluids and electrolytes. Routinely used HPN solutions contain different quantities of these components. Consequently, each HPN solution may have different impacts on metabolism, inflammation and oxidative stress. Long-term use of HPN can lead to a number of adverse health outcomes including the development of metabolic bone disease, intestinal failure associated liver disease and poor quality of life but whether, and how, the composition of HPN solutions contributes to these health sequelae is poorly understood. The aim of this study is to systematically review and evaluate the evidence for the differential effects of HPN solutions and to understand what features are associated with differences in clinical endpoints. METHODS: A systematic literature search was conducted between September and December 2020, and updated in July 2021 using the MEDLINE (Ovid), EMBASE, Scopus, and Web of Science databases. Studies were selected according to the following criteria (a) adult participants (>18 years old) dependent on HPN; (b) randomised controlled trials, prospective cohort and cross-sectional study designs; (c) primary research comparing two or more HPN solutions and (d) published in English language. Data were extracted and study quality assessed using Cochrane Collaboration's tools: Risk of Bias for Randomised Controlled Trials (RCTs); Risk of Bias in Non-Randomised Studies of Interventions; and the Newcastle Ottawa Scale for cross-sectional studies. RESULTS: Of the 5148 articles identified, seven RCTs, two prospective cohort and one cross-sectional study were included with a total of 295 participants. Studies varied in terms of duration (one to 60 months) and sample size (n = 5 to 88). Ten studies compared lipid emulsions (LE) and one study also compared LE with lipid-free HPN. No studies were found that compared the amino acid, vitamin, trace element or electrolyte components of HPN. In general, LE were well tolerated with no significant adverse effects. LE containing olive +/or fish oil were associated with a lower ω-6:ω-3 fatty acid ratio, positive reductions in markers of liver function, and changes in blood and cell fatty acid profiles. CONCLUSIONS: Despite the increasing use of HPN, there is surprisingly little evidence available to guide the provision of macro and micronutrients in the adult population requiring this therapy. Although LE containing olive +/or fish oil show promise with regards to liver function and blood and cell fatty acid profiles, further studies are needed before drawing definitive conclusions on the clinical value of these emulsions. It is likely that one type of HPN solution alone cannot be uniformly applied to patient care, and each patient should be assessed on an individual basis.

Alteration of the gut microbiome in mycophenolate-induced enteropathy: impacts on the profile of short-chain fatty acids in a mouse model.

BACKGROUND: Mycophenolic acid (MPA) is the most widely used immunosuppressive drug in transplantation and for autoimmune diseases. Unfortunately, more than 30% of patients experience a typical gastrointestinal adverse effect also referred to as mycophenolate-induced enteropathy. Due to its antibacterial, antifungal, and antiviral properties, MPA exposure is associated with intestinal dysbiosis characterized by a decrease in density and diversity of the microbiome regarding the main bacterial phyla (Firmicutes and Bacteroidetes). These bacterial phyla are known for their metabolic role in maintaining the homeostasis of the digestive tract, particularly through the production of short-chain fatty acids (SCFA) that could contribute to the pathophysiology of mycophenolate-induced enteropathy. Our study aimed at deciphering short-chain fatty acids (SCFA) profile alterations associated with gastrointestinal toxicity of MPA at the digestive and systemic levels in a mouse model. METHODS: Ten-week old C57BL/6 (SOPF) mice were randomly assigned in 2 groups of 9 subjects: control, and mycophenolate mofetil (MMF, 900 mg/kg/day). All mice were daily treated by oral gavage for 7 days. Individual faecal pellets were collected at days 0, 4 and 8 as well as plasma at day 8 for SCFA profiling. Additionally, after the sacrifice on day 8, the caecum was weighted, and colon length was measured. The proximal colon was cut for histological analysis. RESULTS: MMF treatment induced around 10% weight loss at the end of the protocol associated with a significant decrease in caecum weight and a slight reduction in colon length. Histological analysis showed significant architectural changes in colon epithelium. Moreover, we observed an overall decrease in SCFA concentrations in faecal samples, especially regarding acetate (at day 8, control 1040.6 ± 278.161 µM versus MMF 384.7 ± 80.5 µM, p < 0.01) and propionate (at day 8, control 185.94 ± 51.96 µM versus MMF 44.07 ± 14.66 µM, p < 0.001), and in plasma samples for butyrate (at day 8, control 0.91 ± 0.1 µM versus MMF 0.46 ± 0.1 µM, p < 0.01). CONCLUSIONS: These results are consistent with functional impairment of the gut microbiome linked with digestive or systemic defects during MMF treatment.

Genetic basis and hematologic manifestations of sitosterolemia in a group of Turkish patients.

BACKGROUND: Sitosterolemia is a rare lipid disorder caused by mutations in adenosine triphosphate-binding cassette genes (ABCG) 5 and 8. OBJECTIVE: To evaluate the phenotypic/genotypic features of sitosterolemia in a group of Turkish patients. METHODS: Seven probands with unexplained hematologic abnormalities and their 13 relatives were enrolled. Sterol levels were measured by gas chromatography and genetic studies were performed using Sanger sequencing. Individuals were diagnosed with sitosterolemia if they were found to have frankly elevated sitosterol level >15 µg/mL and/or pathogenic variants of the ABCG5/ABCG8. RESULTS: The seven probands and their six relatives  were diagnosed with frank sitosterolemia, and all these patients had hematologic abnormalities. The remaining seven relatives were asymptomatic heterozygous carriers. Three novel variants in the ABCG5 gene (c.161G>A, c.1375C>T, IVS10-1G>T), one novel variant in the ABCG8 gene (c.1762G>C) and one known variant in the ABCG5 gene (c.1336 C>T) were identified. No variant was identified in one case. The mean sitosterol level was significantly higher and mean platelet count was significantly lower in patients with homozygous variants compared to heterozygous variants (p<0.05, for all). Diets low in plant sterols were recommended for 13 symptomatic cases. Four homozygotes received ezetimibe, and their splenomegaly, anemia, and thrombocytopenia completely resolved except one. CONCLUSION: The five pathogenic variants identified in this study indicate the genetic heterogeneity of sitosterolemia in Turkish population. Patients with unexplained hematologic abnormalities (specifically macrothrombocytopenia) should have their sterol level measured as initial testing. Ezetimibe can be a good choice for sitosterolemia.

Biomarkers of environmental enteric dysfunction are not consistently associated with linear growth velocity in rural Zimbabwean infants.

BACKGROUND: Child stunting remains a poorly understood, prevalent public health problem. Environmental enteric dysfunction (EED) is hypothesized to be an important underlying cause. OBJECTIVES: Within a subgroup of 1169 children enrolled in the SHINE (Sanitation Hygiene Infant Nutrition Efficacy) trial in rural Zimbabwe, followed longitudinally from birth to 18 mo of age, we evaluated associations between the concentration of 11 EED biomarkers and linear growth velocity. METHODS: At infant ages 1, 3, 6, 12, and 18 mo, nurses measured child length and collected stool and blood; the lactulose-mannitol urine test was also conducted at all visits except at 1 mo. Stool neopterin, α-1 antitrypsin, myeloperoxidase, and regenerating gene 1ß protein; urinary lactulose and mannitol; and plasma kynurenine, tryptophan, C-reactive protein, insulin-like growth factor-1 (IGF-1), soluble CD14, intestinal fatty acid binding protein, and citrulline were measured. We analyzed the change in relative [∆ length-for-age z score (LAZ)/mo] and absolute (∆ length/mo) growth velocity during 4 age intervals (1-3 mo; 3-6 mo; 6-12 mo; and 12-18 mo) per SD increase in biomarker concentration at the start of each age interval. RESULTS: In fully adjusted models, we observed only 3 small, statistically significant associations: kynurenine:tryptophan ratio at 12 mo was associated with decreased mean LAZ velocity during the 12-18 mo interval (-0.015 LAZ/mo; 95% CI: -0.029, -0.001 LAZ/mo); mannitol excretion at 6 mo was associated with increased LAZ velocity during the 6-12 mo interval (0.013 LAZ/mo; 95% CI: 0.001, 0.025 LAZ/mo), and plasma IGF-1 at 1 mo was associated with increased LAZ velocity during the 1-3 mo interval (0.118 LAZ/mo; 95% CI: 0.024, 0.211 LAZ/mo). Results for absolute growth velocity were similar, except IGF-1 was also associated with growth during the 12-18 mo interval. We found no other associations between any EED biomarker and linear growth velocity. CONCLUSIONS: None of 11 biomarkers of EED were consistently associated with linear growth among Zimbabwean children.This trial was registered at clinicaltrials.gov as NCT01824940.

Influence of different intravenous lipid emulsions on fatty acid status and laboratory and clinical outcomes in adult patients receiving home parenteral nutrition: A systematic review.

BACKGROUND & AIMS: Patients who have chronic intestinal failure require home parenteral nutrition (HPN) support. Intravenous lipid emulsions (IVLEs) are a vital part of HPN. The conventional IVLE is based on pure soybean oil, which contains a high concentration of omega-6 fatty acids. Alternative IVLEs are commercially available. These contain various oil blends and have different fatty acid compositions from soybean oil that could provide benefit to patients on HPN. The aim of this systematic review is to assess the effects of different IVLEs in adult patients requiring HPN. METHODS: A systematic literature search was conducted up to October 2019 using relevant search terms in the Medline, EMBASE and CINAHL databases. Only randomised controlled trials (RCTs) in adults on HPN that compared two or more IVLEs were included. Data were extracted and the Cochrane Collaboration's tool for assessing risk of bias was used. RESULTS: Six articles were identified for inclusion in this systematic review. Studies differed according to sample size, duration and the IVLEs compared. Four studies found no increased risk of adverse effects related to the different IVLEs, whilst one study found a higher frequency of serious adverse events with soybean oil. One study found higher serum α-tocopherol with the blend of soybean oil, medium chain triglycerides, olive oil and fish oil. Inflammatory markers were not affected by different IVLEs in three studies. Differences in liver function tests were minimal, but one study found slight abnormalities in patients receiving soybean oil. IVLEs containing olive oil or fish oil modified the blood fatty acid profile. No studies reported essential fatty acid deficiency. CONCLUSIONS: There may be benefits of using alternative IVLEs to soybean oil-based emulsions in adults requiring HPN, although there is currently insufficient evidence to determine superiority of one formulation over another. More and larger RCTs are required in this area.

The ω-3 Polyunsaturated Fatty Acids and Oxidative Stress in Long-Term Parenteral Nutrition Dependent Adult Patients: Functional Lipidomics Approach.

Omega-3 polyunsaturated fatty acids (ω-3PUFAs) are introduced into parenteral nutrition (PN) as hepatoprotective but may be susceptible to the lipid peroxidation while olive oil (OO) is declared more peroxidation resistant. We aimed to estimate how the lipid composition of PN mixture affects plasma and erythrocyte lipidome and the propensity of oxidative stress. A cross-sectional comparative study was performed in a cohort of adult patients who were long-term parenterally administered ω-3 PUFAs without (FO/-, n = 9) or with (FO/OO, n = 13) olive oil and healthy age- and sex-matched controls, (n = 30). Lipoperoxidation assessed as plasma and erythrocyte malondialdehyde content was increased in both FO/- and FO/OO groups but protein oxidative stress (protein carbonyls in plasma) and low redox status (GSH/GSSG in erythrocytes) was detected only in the FO/- subcohort. The lipidome of all subjects receiving ω-3 PUFAs was enriched with lipid species containing ω-3 PUFAs (FO/-˃FO/OO). Common characteristic of all PN-dependent patients was high content of fatty acyl-esters of hydroxy-fatty acids (FAHFAs) in plasma while acylcarnitines and ceramides were enriched in erythrocytes. Plasma and erythrocyte concentrations of plasmanyls and plasmalogens (endogenous antioxidants) were decreased in both patient groups with a significantly more pronounced effect in FO/-. We confirmed the protective effect of OO in PN mixtures containing ω-3 PUFAs.

Diagnostic Accuracy of Intestinal Fatty Acid Binding Protein for Acute Intestinal Ischemia: a Systematic Review and Meta-Analysis.

BACKGROUND: Some studies have investigated the diagnostic value of intestinal fatty acid binding protein (I-FABP) for acute intestinal ischemia (II), but the results were not always consistent. Therefore, we performed a systematic review and meta-analysis to determine the diagnostic accuracy of I-FABP for II. METHODS: Publications included in the PubMed and EMBASE before April 7, 2019 were retrieved to identify studies investigating the diagnostic accuracy of I-FABP for II. The Revised Tool for the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used to assess the quality of eligible studies. Diagnostic accuracy of I-FABP in all eligible studies was pooled by a bivariate model. Summary receiver operating characteristic (ROC) curves (AUC) were constructed to calculate the overall diagnostic accuracy of I-FABP. RESULTS: A total of 10 studies with 1,265 (219 IIs and 1,046 controls) subjects were included in this systematic review and meta-analysis. The major design weaknesses of included studies were patient selection bias. The overall diagnostic sensitivity, specificity, and AUC of I-FABP were 0.75 (95% CI: 0.68 - 0.82), 0.85 (95% CI: 0.74 - 0.92), and 0.82 (95% CI: 0.79 - 0.86), respectively. In patients with acute abdominal pain, the sensitivity, specificity, and AUC of I-FABP were 0.71 (95% CI: 0.59 - 0.81), 0.89 (95% CI: 0.69 - 0.97) and 0.80 (95% CI: 0.76 - 0.83), respectively. CONCLUSIONS: I-FABP has moderate diagnostic accuracy for II. Due the patient selection bias of available studies, further studies with rigorous design are needed to evaluate the diagnostic accuracy of I-FABP for II.

Plasma Levels of the Bioactive Sphingolipid Metabolite S1P in Adult Cystic Fibrosis Patients: Potential Target for Immunonutrition?

Recent research has linked sphingolipid (SL) metabolism with cystic fibrosis transmembrane conductance regulator (CFTR) activity, affecting bioactive lipid mediator sphingosine-1-phosphate (S1P). We hypothesize that loss of CFTR function in cystic fibrosis (CF) patients influenced plasma S1P levels. Total and unbound plasma S1P levels were measured in 20 lung-transplanted adult CF patients and 20 healthy controls by mass spectrometry and enzyme-linked immunosorbent assay (ELISA). S1P levels were correlated with CFTR genotype, routine laboratory parameters, lung function and pathogen colonization, and clinical symptoms. Compared to controls, CF patients showed lower unbound plasma S1P, whereas total S1P levels did not differ. A positive correlation of total and unbound S1P levels was found in healthy controls, but not in CF patients. Higher unbound S1P levels were measured in ΔF508-homozygous compared to ΔF508-heterozygous CF patients (p = 0.038), accompanied by higher levels of HDL in ΔF508-heterozygous patients. Gastrointestinal symptoms were more common in ΔF508 heterozygotes compared to ΔF508 homozygotes. This is the first clinical study linking plasma S1P levels with CFTR function and clinical presentation in adult CF patients. Given the emerging role of immunonutrition in CF, our study might pave the way for using S1P as a novel biomarker and nutritional target in CF.

Features of Sitosterolemia in Children.

Sitosterolemia is a rare lipid metabolism disease with heterogeneous manifestations. Atherosclerosis can occur in children, and therefore, early detection, diagnosis, and treatment of this disease are important. We studied 18 pediatric patients with sitosterolemia who showed a significant increase in plasma lipid levels and analyzed their clinical, biochemical, and genetic characteristics. We recorded the initial serum lipid results and clinical manifestations of the patients. Lipid and plant sterol levels were measured after homozygous or compound heterozygous mutations of ABCG5 or ABCG8 were identified by genetic testing. Plasma plant sterol levels were analyzed by gas chromatography. Fourteen cases of sitosterolemia were examined by ultrasound and echocardiography. The initial total cholesterol and low-density lipoprotein levels of the children were significantly increased, but then markedly decreased after diet control or drug treatment, and even reached normal levels. Carotid atherosclerosis and aortic valve regurgitation were present in three of 14 patients. Serum lipid levels of children with sitosterolemia and xanthomas were notably higher than those without xanthomas. There were no significant differences in clinical manifestations between patients with different genotypes. In conclusion, sitosterolemia should be considered in children with hyperlipidemia who do not present with xanthomas, especially with a significant increase in total cholesterol and low-density lipoprotein levels. There does not appear to be a correlation between clinical phenotype and genotype.

Intestinal barrier dysfunction in liver cirrhosis assessed by iohexol test.

OBJECTIVE: To study gut barrier function in patients with liver cirrhosis (LC) by evaluating the intestinal permeability (IP) and its relationship with the severity and etiology of the disease. PATIENTS AND METHODS: The study included 31 patients with LC and 25 healthy controls. Child-Pugh score was used for evaluation of the LC severity. IP was assessed by the rise in levels of iohexol, which was administered orally (25 mL, 350 mg/mL) 2 h after breakfast. Three and six hours later serum (SIC mg/L) and urine (UIC g/mol) iohexol concentrations were determined by a validated HPLC-UV technique. RESULTS: Patients with LC had significantly higher mean SIC value compared with control group at 3 h (2.05 ± 1.67 vs. 1.25 ± 1.41 mg/L, p=0.021, as well as at 6 h (2.20 ± 2.65 vs. 1.11 ± 1.06 mg/L, p=0.001) after ingestion. No significant difference was found in mean SIC value of patients at 3 and 6 h. 23% of the patients had an increased IP. The mean iohexol urine recovery of patients was similar to that of the controls both at 3 h and at 6 h. Mean SIC values were significantly higher in patients with advanced Child C class than in healthy controls or the subgroup with Child B class, both at 3 h (2.54 ± 1.95 mg/L vs. 1.11 ± 1.06 mg/L, p=0.007) or (2.57 ± 1.85 mg/L vs. 1.35±1.32 mg/L, p=0.005) and at 6 h (2.57 ± 1.85 mg/L vs. 1.25 ± 1.40 mg/L, p=0.002) or 2.54 ± 1.95 mg/L vs. 1.07 ± 0.35 mg/L, p=0.02). Cirrhotic patients with ascites had significantly higher SIC in comparison with the controls, both at 3 h (2.31 ± 1.74 vs. 1.25 ± 1.41 mg/, p=0.009) and at 6 h (2.20 ± 1.87 vs. 1.11 ± 1.06 mg/l, p=0.007). In the subgroup of patients with alcoholic LC, the mean SIC values at 3 and 6 h (2.29 ± 1.80, 2.33 ± 1.85 mg/L, respectively) were significantly higher (p= 0.016, p=0.003) compared to the control group (1.25 ± 1.41, 1.11 ± 1.06 mg/L, respectively). CONCLUSIONS: Increased IP is found in 23% of cirrhotic patients. Permeability alterations are significantly more pronounced in patients with advanced LC with the presence of ascites and in those with alcoholic etiology.

Sensitivity of differential time to positivity compared to pour plates for diagnosing catheter-related blood stream infection: An evaluation in patients with chronic intestinal failure.

BACKGROUND & AIMS: A retrospective evaluation was undertaken in intestinal failure (IF) patients with long term CVCs to evaluate differential time to positivity (DTP) against paired quantitative blood cultures (PP) for the diagnosis of CRBSI. METHODS: A list of patients with a diagnosis of CRBSI was obtained from the intestinal failure unit database for a five year period, 2013 to 2017. Microbiology records were reviewed to obtain further information about blood culture and pour plate examinations. Organisms and times of collection, loading and positivity were recorded. Patients with a contemporaneous set of central and peripheral PP and blood cultures were included in an analysis of the sensitivity of DTP compared to PP. RESULTS: There were 61 (45.5%) episodes in 56 patients where complete sets of central and peripheral blood cultures and PP were received. All 61 episodes had positive central blood cultures, 59 (96.7%) had positive central line PP and 17 (27.9%) had positive peripheral PP. Using PP as the gold standard, DTP sensitivity was 96.0% for 50 episodes where PP were consistent with CRBSI. Sensitivity increased to 100% for 17 episodes where there were no delays in either collection or loading of blood cultures. CONCLUSIONS: This is the first evaluation to support the use of DTP as a sensitive test in diagnosing CRBSI in patients with IF and provides confidence to IF centers where pour plate cultures are not available.

Phytosterolemia and γ-glutamyl transferase in adults with parenteral nutrition: Fish versus vegetal lipids: A randomized clinical trial.

OBJECTIVES: Fish oil (FO)-based lipid emulsions (LEs) have been reported to prevent hepatic dysfunction in patients treated with parenteral nutrition (PN). We studied patients with alterations of γ-glutamyl transferase (GGT) associated with the administration of PN containing olive/soybean (O/S)-based LE. The aim of this study was to determine whether the strategy of reducing the lipid dose by 50%, by changing to an FO-based LE, reduced plasma levels of phytosterols (PS) and GGT more effectively and safely, than the strategy of reducing lipid contribution by 50% while maintaining the same LE composition. METHODS: A randomized double-blind clinical trial was carried out in patients with normal initial GGT, who after a minimum of 1 wk of daily PN (0.8 g/kg of O/S-based LE) presented with GGT values twice the upper normal value. At the time of randomization 1:1, lipids were reduced to 0.4 g/kg daily. Group A maintained O/S LE and group B changed to FO LE. The primary endpoints were reduction of plasmatic PS and GGT on day 7 after randomization, performed in the study population per protocol by Student's t test and simple linear regression. Secondary outcomes included alkaline phosphatase (AP), alanine transaminase (ALT), and total bilirubin (BIL), and safety variables. RESULTS: Nineteen patients were included. On day 7 after randomization, GGT and AP values were higher in the O/S group (n = 10; GGT: median [Med], 4.99; interquartile range [IQR], 4.09; AP: Med, 2.59 µkat/L; IQR 1.74) than in the FO group (n = 9; GGT: Med, 2.26 µkat/L; IQR, 1.07; AP: Med, 1.2 µkat/L; IQR 1.44). Although there were no differences in ALT and BIL values, the ALT decrease was larger and more statistically significant in the FO group than in the O/S group (P = 0.009). Total PS (Med, 21.10 µg/mL; IQR, 5.50) in the O/S group was higher than in the FO group (Med, 13.4 µg/mL; IQR, 10.65; P = 0.002). Significant decreases in PS and their fractions were observed, with the exception of campesterol and stigmasterol. CONCLUSION: Plasma accumulation of PS and high values of GGT, AP, and ALT can be prevented with the exclusive administration of FO-based LE.

Efficacy of Sox10 Promoter Methylation in the Diagnosis of Intestinal Neuronal Dysplasia From the Peripheral Blood.

OBJECTIVES: Intestinal neuronal dysplasia (IND) is a common malformation of the enteric nervous system. Diagnosis requires a full-thickness colonic specimen and an experienced pathologist, emphasizing the need for noninvasive analytical methods. Recently, the methylation level of the Sox10 promoter has been found to be critical for enteric nervous system development. However, whether it can be used for diagnostic purposes in IND is unclear. METHODS: Blood and colon specimens were collected from 32 patients with IND, 60 patients with Hirschsprung disease (HD), and 60 controls. Sox10 promoter methylation in the blood and the Sox10 expression level in the colon were determined, and their correlation was analyzed. The diagnostic efficacy of blood Sox10 promoter methylation was analyzed by receiver operating characteristic curve. RESULTS: The blood level of Sox10 promoter methylation at the 32nd locus was 100% (90%-100%; 95% confidence interval [CI], 92.29%-96.37%) in control, 90% (80%-90%; 95% CI, 82.84%-87.83%) in HD, and 60% (50%-80%; 95% CI, 57.12%-69.76%) in IND specimens. Sox10 promoter methylation in the peripheral blood was negatively correlated with Sox10 expression in the colon, which was low in control, moderate in HD, and high in IND specimens (r = -0.89). The area under the curve of Sox10 promoter methylation in the diagnosis of IND was 0.94 (95% CI, 0.874-1.000, P = 0.000), with a cutoff value of 85% (sensitivity, 90.6%; specificity, 95.0%). By applying a cutoff value of 65%, promoter methylation was more indicative of IND than HD. DISCUSSION: The analysis of Sox10 promoter methylation in the peripheral blood can be used as a noninvasive method for IND diagnosis.

Identification of potential molecular pathogenesis mechanisms modulated by microRNAs in patients with Intestinal Neuronal Dysplasia type B.

This study proposed to determine global microRNA (miRNA) expression and miRNA-regulated pathways in Intestinal Neuronal Dysplasia type B (IND-B). Fifty patients (0-15 years old) with IND-B were included in the study. Peripheral blood samples were collected from all 50 patients and from 10 healthy asymptomatic children (controls). Rectal biopsies were collected from 29/50 patients; biopsy tissues were needle microdissected to isolate the different intestinal layers, for molecular analysis. Global miRNA expression was determined using TaqMan arrays. Correlation analysis between miRNA expression in plasma and biopsy samples as well as among tissues derived from the distinct intestinal layers was performed. Computational approaches were used for miRNA target prediction/identification of miRNA-regulated genes and enriched pathways biologically relevant to IND-B pathogenesis. miRNAs were statistically significantly deregulated (FC ≥ 2 and p ≤ 0.05) in submucosal and muscular layers: over-expressed (miR-146a and miR-146b) and under-expressed (miR-99a, miR-100, miR-130a, miR-133b, miR-145, miR-365, miR-374-5p, miR-451). Notably, let-7a-5p was highly over-expressed in patient plasma compared to healthy controls (FC = 17.4). In addition, miR-451 was significantly under-expressed in both plasma and all biopsy tissues from the same patients. Enriched pathways (p < 0.01) were axon guidance, nerve growth factor signalling, NCAM signalling for neurite out-growth, neuronal system and apoptosis. miRNA expression is deregulated in the submucosa and muscular layers of the rectum and detected in plasma from patients with IND-B. Biologically enriched pathways regulated by the identified miRNAs may play a role in IND-B disease pathogenesis, due to the activity related to the neurons of the enteric nervous system.