Intestinal failure-associated liver disease: Current challenges in screening, diagnosis, and parenteral nutrition considerations

Intestinal failure-associated liver disease (IFALD) is a serious life-limiting complication that can occur throughout the clinical course of intestinal failure and its management by parenteral nutrition (PN). Despite this, there is a lack of a standardized definition for IFALD, which makes this insidious condition increasingly difficult to screen and diagnose in clinical practice. Attenuating the progression of liver disease before the onset of liver failure is key to improving morbidity and mortality in these patients. This requires timely detection and promptly addressing reversible factors. Although there are various noninvasive tools available to the clinician to detect early fibrosis or cirrhosis in various chronic liver disease states, these have not been validated in the patient population with IFALD. Such tools include biochemical composite scoring systems for fibrosis, transient elastography, and dynamic liver function tests. This review article aims to highlight the existing real need for an accurate, reproducible method to detect IFALD in its early stages. In addition, we also explore the role PN plays in the pathogenesis of this complex multifactorial condition. Various aspects of PN administration have been implicated in the etiology of IFALD, including the composition of the lipid component, nutrient excess and deficiency, and infusion timing. We aim to highlight the clinical relevance of these PN-associated factors in the development of IFALD and how these can be managed to mitigate the progression of IFALD.

Parenteral Nutrition, Sepsis, Acute Heart Failure and Hepatotoxic Drugs Are Related to Liver Test Disturbances in Critically Ill Patients

BACKGROUND

Parenteral nutrition (PN) is often associated with liver dysfunction in the ICU, although other factors such as sepsis, acute heart failure (AHF), and hepatotoxic drugs can be equally present. The relative impact of PN on liver dysfunction in critically ill patients is largely unknown.

METHODS

We recorded the presence of pre-existing liver disturbances, AHF, sepsis, daily PN volume, and commonly used hepatotoxic drugs in adult ICU patients, together with daily aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), alkalic phosphatase (AP), total bilirubin (TB), and INR values in patients with three or more PN treatment days. A linear mixed-effects model was used to assess the relative contribution of each liver parameter. Nutritional adequacy was defined as intake/needs.

RESULTS

We included 224 ICU patients with PN treatment lasting more than 3 days between 1 January 2017 and 31 December 2019. For AST, pre-existing liver disturbances (+180% ± 11%) and the presence of AHF (+75% ± 14%) were the main predictors of deterioration, whereas PN volume caused only a limited increase of 14% ± 1%/L. Similar results were observed for ALT. GGT, INR, and TB are mainly influenced by the presence of sepsis/septic shock and pre-existing liver disturbances, with no impact of PN or hepatotoxic drugs. Carbohydrate intake exceeded recommendations, and protein and lipid intake were insufficient in this study cohort.

CONCLUSIONS

Liver test disturbances in ICU patients on PN are multifactorial, with sepsis and AHF having the highest influence, with only limited impact from PN and hepatotoxic drugs. Feeding adequacy can be improved.

Evaluation of Emulsifying Ability of Phospholipids by Langmuir Monolayers and Stability of High Oil Ratio O/W Emulsions

High oil ratio fat emulsion injections are prone to poor emulsification, rapid creaming, and other quality problems; therefore, the selection of emulsifiers with high emulsifying ability is crucial for the production of fat emulsions. The existing methods used to evaluate the emulsifying ability of emulsifier are to evaluate the emulsifying ability from the emulsifier itself. In the study, Langmuir monolayer selected the most miscible phospholipid with oil phase from the alternative three phospholipids by studying the molecular interaction between oil phase and phospholipid at the air/water interface. The miscibility and thermodynamic stability analyses of the different oil phase/phospholipid mixed monolayers were performed, and the data from [Formula: see text] and [Formula: see text] concluded that all three oil phases had the strongest molecular interaction with E80 and the best miscibility. The emulsions were then prepared and analyzed by the results of particle size, ζ-potential, and stability of the emulsions, where the surface free energy in the stability test echoed the results reflected by the [Formula: see text] values in the thermodynamic stability test. These results indicate that Langmuir monolayers can be used to study the interaction between oil phase and emulsifier, thus providing new ideas for evaluating the emulsifying ability of phospholipids.

Risk factors of parenteral nutrition-associated cholestasis in very-low-birthweight infants

AIM

We aimed to explore risk factors associated with parenteral nutrition-associated cholestasis (PNAC) in very-low-birthweight (VLBW) infants.

METHODS

VLBW infants receiving parenteral nutrition (PN) for at least 14 days were enrolled in a retrospective dual-centre study and divided into two groups chronologically: group A (2000-2007) and group B (2008-2015). The incidence of PNAC and related factors were investigated. We compared the differences between PNAC and non-PNAC groups. A multivariate binary logistic regression analysis was carried out to identify the potential risk factors of PNAC.

RESULTS

A total of 387 VLBW infants (53 in group A and 334 in group B) were enrolled in the study. The total incidence of PNAC was 6.7%, 9.4% in group A and 6.3% in group B. The dosage of amino acid (P = 0.009), glucose (P = 0.006), PN calories (P = 0.021) and the ratio of glucose/fat (P = 0.014) were significantly higher in group B than in group A. Non-protein energy to nitrogen ratio (P = 0.017) was lower in group B. Birthweight was significantly lower in the PNAC group than in the non-PNAC group (P = 0.021). Subgroup analysis showed that gestational age and duration of PN were significantly different between the PNAC and non-PNAC groups (P < 0.05). Logistic regression showed that prolonged duration of PN (≥43 days) (odds ratio 3.155, 95% confidence interval 1.009-9.861, P = 0.048) was an independent risk factor of PNAC.

CONCLUSIONS

For VLBW infants, prolonged duration of PN is a risk factor for the development of PNAC. PNAC may be prevented by weaning off PN as early as possible in VLBW infants.

Phytosterolaemia associated with parenteral nutrition administration in adult patients

Vegetable lipid emulsions (LE) contain non-declared phytosterols (PS). We aimed to determine PS content depending on the brand and LE batch, and in adult hospitalised patients treated with parenteral nutrition (PN), to establish the association between plasma and administered PS. Part I was the LE study: totals and fractions of PS in three to four non-consecutive batches from six LE were analysed. Part II was the patient study: patients with at least 7 previous days of PN with 0·8 g/kg per d of an olive/soyabean (O/S) LE were randomised (day 0) 1:1 to O/S or 100 % fish oil (FO) at a dose of 0·4 g/kg per d for 7 d (day 7). Plasma PS, its fractions, total cholesterol on days 0 and 7, their clearance and their association with PS administered by LE were studied. In part I, LE study: differences were found in the total PS, their fractions and cholesterol among different LE brands and batches. Exclusive soyabean LE had the highest content of PS (422·36 (sd 130·46) μg/ml). In part II, patient study: nineteen patients were included. In the O/S group, PS levels were maintained (1·11 (sd 6·98) μg/ml) from day 0 to 7, while in the FO group, significant decreases were seen in total PS (-6·21 (sd 4·73) μg/ml) and their fractions, except for campesterol and stigmasterol. Plasma PS on day 7 were significantly associated with PS administered (R2 0·443). PS content in different LE brands had great variability. PS administered during PN resulted in accumulation and could be prevented with the exclusive administration of FO LE.

Modifying Serum Plant Sterol Concentrations: Effects on Markers for Whole Body Cholesterol Metabolism in Children Receiving Parenteral Nutrition and Intravenous Lipids

Background: Non-cholesterol sterols are validated markers for fractional intestinal cholesterol absorption (cholestanol) and endogenous cholesterol synthesis (lathosterol). This study’s objective was to evaluate markers for cholesterol synthesis and absorption in children exposed to two different intravenous lipid emulsions that rapidly change serum plant sterol concentrations as part of their parenteral nutrition (PN). Methods: Serum samples from two different studies were used: (1) nine PN-dependent children with intestinal failure associated liver disease (IFALD) whose soy-based, plant sterol-rich lipid (SO) was replaced with a fish-based, plant sterol-poor (FO) lipid; and (2) five neonates prescribed SO after birth. In the first study, samples were collected at baseline (prior to FO initiation) and after 3 and 6 months of FO. In study 2, samples were collected at 1 and 3 weeks of age. Results: In study 1, a 7-fold reduction in campesterol, a 12-fold reduction in sitosterol, and a 15-fold reduction in stigmasterol was observed 6 months after switching to FO. Serum cholesterol concentrations did not change, but cholesterol-standardized lathosterol increased (3-fold) and cholesterol-standardized cholestanol decreased (2-fold). In study 2, after 3 weeks of SO, sitosterol and campesterol concentrations increased 4-5 fold. At the same time, cholesterol-standardized lathosterol increased 69% and cholesterol-standardized cholestanol decreased by 29%. Conclusion: Based on these finding we conclude that changes in serum plant sterol concentrations might have direct effects on endogenous cholesterol synthesis, although this needs to be confirmed in future studies. Moreover, we speculate that this changed synthesis subsequently affects intestinal cholesterol absorption.

ESPGHAN Committee on Nutrition Position Paper. Intravenous Lipid Emulsions and Risk of Hepatotoxicity in Infants and Children: a Systematic Review and Meta-analysis

The aim of the present article was to perform a systematic review with meta-analysis of available scientific evidence regarding the role of different intravenous lipid emulsions (ILE) in the pathogenesis of cholestasis and parenteral nutrition-associated liver disease. A systematic review of the literature (up to March 2015) identified 23 randomized controlled trials (RCTs). Of these, 17 were performed in preterm infants or critically ill neonates with a short duration of intervention, 2 in older children with short-term use (following surgery or bone marrow transplantation), 1 in neonates with long-term use, and 3 in infants and children receiving long-term parenteral nutrition (PN). Meta-analysis showed no differences in the rate of cholestasis or bilirubin levels associated with short-term use of different ILEs. Because of high heterogeneity of the long-term studies no meta-analysis could be performed. Available studies found that the use of multicomponent fish oil (FO)-containing ILE compared with pure soya bean oil (SO), ILE-reduced liver enzymes, and bilirubin levels in noncholestatic children on long-term PN and one other RCT found that FO-based ILE-reversed cholestasis in a proportion of patients. The ESPGHAN Committee on Nutrition concludes that there is no evidence of a difference in rates of cholestasis or bilirubin levels between different ILE for short-term use in neonates. The use of multicomponent FO-containing ILE may contribute to a decrease in total bilirubin levels in children with IF on prolonged PN. Well-designed RCTs are, however, lacking and long-term effects have not been determined.

Intestinal failure-associated liver disease: a position paper of the ESPGHAN Working Group of Intestinal Failure and Intestinal Transplantation

Intestinal failure-associated liver disease is the most prevalent complication affecting children with intestinal failure receiving long-term parenteral nutrition. This paper reviews the definition, diagnostic criteria, pathogenesis, and risk factors. The authors discuss the role of enteral nutrition, parenteral nutrition, and its components, especially lipid emulsions. The authors also discuss the surgical treatment, including intestinal transplantation, its indications, technique, and results, and emphasise the importance of specialised intestinal failure centres.

Serum plant sterols, cholestanol, and cholesterol precursors associate with histological liver injury in pediatric onset intestinal failure

BACKGROUND

Increased serum concentrations of plant sterols, including stigmasterol, during parenteral nutrition (PN) have been linked with serum biochemical signs of intestinal failure-associated liver disease (IFALD), whereas clinical data on their correlation to histologic liver injury have been limited.

OBJECTIVE

We studied interrelations between serum noncholesterol sterols and histologic liver injury in pediatric-onset intestinal failure (IF).

DESIGN

Serum plant sterols (stigmasterol, avenasterol, sitosterol, and campesterol), cholestanol, and cholesterol precursors (cholestenol, lathosterol, and desmosterol) were measured in 50 IF patients at a median age 7.3 y and in 86 matched controls. Forty patients underwent liver biopsies. Sixteen patients had been receiving PN for 45 mo, and 34 patients had received PN for 9.1 mo but had not received PN for 5.4 y.

RESULTS

Serum plant sterols were higher in patients who were currently receiving PN than in controls and were related to conjugated bilirubin (r = 0.799-0.541, P < 0.05). During PN, the ratio of serum stigmasterol to cholesterol was 3.3-fold higher in patients with portal inflammation, and the ratio of avenasterol to cholesterol was 3.9-fold higher in patients with cholestasis (P < 0.05 for both). Ratios of stigmasterol and avenasterol to cholesterol were correlated with portal inflammation (r = 0.549-0.510, P < 0.05), cholestasis (r = 0.501-0.491, P = 0.048-0.053), and serum bile acids (r = 0.591-0.608, P < 0.05). The median (IQR) ratio of serum cholestanol to cholesterol was higher during (269 100× μg/mg cholesterol; 203-402 100× μg/mg cholesterol) than after (175 100× μg/mg cholesterol; 156-206 100× μg/mg cholesterol; P < 0.001) weaning off PN and was correlated with cholestasis (r = 0.428), portal inflammation (r = 0.511), and fibrosis (r = 0.323, P < 0.05 for all). After weaning off PN, ratios of cholestenol and lathosterol to cholesterol were >2-fold higher in patients with persistent liver steatosis than in those without steatosis or controls (P < 0.01 for all), whereas lathosterol was correlated with the steatosis grade (r = 0.320, P < 0.050).

CONCLUSIONS

Increased serum stigmasterol and avenasterol concentrations parallel the portal inflammation and cholestasis during PN, thereby reinforcing their contribution to IFALD. A bile acid malabsorption-driven increase in cholesterol synthesis underpins persistent liver steatosis after weaning off PN. Serum cholestanol reflects liver injury in IF patients.

Phytosterols promote liver injury and Kupffer cell activation in parenteral nutrition-associated liver disease

Parenteral nutrition-associated liver disease (PNALD) is a serious complication of PN in infants who do not tolerate enteral feedings, especially those with acquired or congenital intestinal diseases. Yet, the mechanisms underlying PNALD are poorly understood. It has been suggested that a component of soy oil (SO) lipid emulsions in PN solutions, such as plant sterols (phytosterols), may be responsible for PNALD, and that use of fish oil (FO)-based lipid emulsions may be protective. We used a mouse model of PNALD combining PN infusion with intestinal injury to demonstrate that SO-based PN solution causes liver damage and hepatic macrophage activation and that PN solutions that are FO-based or devoid of all lipids prevent these processes. We have furthermore demonstrated that a factor in the SO lipid emulsions, stigmasterol, promotes cholestasis, liver injury, and liver macrophage activation in this model and that this effect may be mediated through suppression of canalicular bile transporter expression (Abcb11/BSEP, Abcc2/MRP2) via antagonism of the nuclear receptors Fxr and Lxr, and failure of up-regulation of the hepatic sterol exporters (Abcg5/g8/ABCG5/8). This study provides experimental evidence that plant sterols in lipid emulsions are a major factor responsible for PNALD and that the absence or reduction of plant sterols is one of the mechanisms for hepatic protection in infants receiving FO-based PN or lipid minimization PN treatment. Modification of lipid constituents in PN solutions is thus a promising strategy to reduce incidence and severity of PNALD.

Pathogenesis and treatment of parenteral nutrition-associated liver disease

BACKGROUND

Parenteral nutrition-associated liver disease (PNALD) has been common in patients who require long-term parenteral nutrition. PNALD develops in 40%-60% of infants on long-term parenteral nutrition compared with 15%-40% of adults on home parenteral nutrition for intestinal failure. The pathogenesis of PNALD is multifactorial and remains unclear. There is no specific treatment. Management strategies for its prevention and treatment depend on an understanding of many risk factors. This review aims to provide an update on the pathogenesis and treatment of this disease.

DATA SOURCES

A literature search was performed on the MEDLINE and Web of Science databases for articles published up to October 2011, using the keywords: parenteral nutrition associated liver disease, intestinal failure associated liver disease, lipid emulsions and fish oil. The available data reported in the relevant literatures were analyzed.

RESULTS

The literature search provided a huge amount of evidence about the pathogenesis and management strategies on PNALD. Currently, lack of enteral feeding, extended duration of parenteral nutrition, recurrent sepsis, and nutrient deficiency or excess may play important roles in the pathogenesis of PNALD. Recent studies found that phytosterols, present as contaminants in soy-based lipid emulsions, are also an important factor in the pathogenesis. Moreover, the treatment of PNALD is discussed.

CONCLUSIONS

The use of lipid emulsions, phytosterols in particular, is associated with PNALD. Management strategies for the prevention and treatment of PNALD include consideration of early enteral feeding, the use of specialized lipid emulsions such as fish oil emulsions, and isolated small bowel or combined liver and small bowel transplantation. A greater understanding of the pathogenesis of PNALD has led to promising interventions to prevent and treat this condition. Future work should aim to better understand the mechanisms of PNALD and the long-term outcomes of its treatment.

Steroidal compounds in commercial parenteral lipid emulsions

Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn(®) II, Liposyn(®) III, Lipofundin(®) MCT, Lipofundin(®) N, Structolipid(®), Intralipid(®), Ivelip(®) and ClinOleic(®). Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction.

Parenteral plant sterols and intestinal failure-associated liver disease in neonates

OBJECTIVES

We prospectively evaluated incidence of prolonged (>28 days) parenteral nutrition (PN), associated complications, and significance of parenteral plant sterols (PS) in neonatal intestinal failure-associated liver disease (IFALD) compared with children.

METHODS

We recruited 28 neonates (mean age 50 days, range 28-126) and 11 children (6.9 y, 2.1-16.6) in all of Finland. Patients underwent repeated measurements of serum cholesterol, noncholesterol sterols, including PS, cholestanol and cholesterol precursors, and liver biochemistry during and 1 month after discontinuation of PN. Healthy matched neonates (n=10) and children (n=22) served as controls.

RESULTS

IFALD occurred more frequently among neonates (63%) than children (27%; P<0.05). Ratios of serum PS, including stigmasterol, sitosterol, avenasterol, and campesterol, and total PS were increased among neonates compared with healthy controls and children on PN by 2- to 22- and 2- to 5-fold (P<0.005), respectively. Neonates with IFALD had significantly higher ratios of serum PS and cholestanol compared with neonates without IFALD (P<0.05). Total duration of PN associated with serum cholestanol, stigmasterol, avenasterol, alanine aminotransferase, and aspartate aminotransferase (r=0.472-0.636, P<0.05). Cholestanol and individual serum PS, excluding campesterol, reflected direct bilirubin (r=0.529-0.688, P<0.05). IFALD persisted after discontinuation of PN in 25% of neonates with 4.2- and 2.2-times higher ratios of serum stigmasterol and cholestanol compared with neonates without IFALD (P<0.05).

CONCLUSIONS

Frequent occurrence of IFALD among neonates on PN displays an association to duration of PN and markedly increased serum PS, especially stigmasterol, in comparison to healthy neonates and children on PN. Striking accumulation of parenteral PS may contribute to IFALD among neonates.

Effects of long-term parenteral nutrition on serum lipids, plant sterols, cholesterol metabolism, and liver histology in pediatric intestinal failure

BACKGROUND AND OBJECTIVE

Plant sterols (PS) in parenteral nutrition (PN) may contribute to intestinal failure-associated liver disease. We investigated interrelations between serum PS, liver function and histology, cholesterol metabolism, and characteristics of PN.

PATIENTS AND METHODS

Eleven patients with intestinal failure (mean age 6.3 years) receiving long-term PN were studied prospectively (mean 254 days) and underwent repeated measurements of serum lipids, noncholesterol sterols, including PS, and liver enzymes. PS contents of PN were analyzed. Liver biopsy was obtained in 8 patients. Twenty healthy children (mean age 5.7 years) served as controls.

RESULTS

Median percentage of parenteral energy of total daily energy (PN%) was 48%, including 0.9 g · kg(-1) · day(-1) of lipids. Respective amounts of PN sitosterol, campesterol, avenasterol, and stigmasterol were 683, 71, 57, and 45 μg · kg(-1) · day(-1). Median serum concentrations of sitosterol (48 vs 7.5 μmol/L, P < 0.001), avenasterol (2.9 vs 1.9, P < 0.01), stigmasterol (1.9 vs 1.2, P < 0.005), but not that of campesterol (9.8 vs 12, P = 0.22), were increased among patients in relation to controls, and correlated with PN% (r = 0.81-0.88, P < 0.005), but not with PN fat. Serum cholesterol precursors were higher in patients than in controls. Serum liver enzymes remained close to normal range. Glutamyl transferase correlated with serum PS (r = 0.61-0.62, P < 0.05). Liver fibrosis in 5 patients reflected increased serum PS (r = 0.55-0.60, P = 0.16-0.12).

CONCLUSIONS

Serum PS moderately increase during olive oil-based PN, and correlate positively with PN% and glutamyl transferase. Despite well-preserved liver function, histology often revealed significant liver damage.

The use of Omegaven in treating parenteral nutrition-associated liver disease

Parenteral nutrition (PN), containing fat emulsions derived from soybean, has been implicated in the progression of PN-associated liver disease and cholestasis, particularly in infants with short bowel syndrome. Clinical use of Omegaven, a parenteral fish-oil emulsion, has been shown in recent studies to be a promising therapy to reverse liver disease and cholestasis. This review summarizes the rationale, relevant clinical investigations and future direction of Omegaven therapy for PN-dependent infants.

Olive Oil‐Based Fat Emulsion Versus Soy Oil‐Based Fat Emulsion in Abdominal Oncologic Surgery

In parenteral nutrition (PN), essential fatty acids are provided by soy oil‐based fat emulsions, which may exert adverse effects on the immune system and lipid peroxidation. Olive oil ‐based fat emulsions have been said to prevent these undesired effects. This study compares effects of olive oil ‐ and soy oil ‐based fat emulsions in 22 patients who underwent abdominal surgery for cancer. The first group (n = 10) received soy oil ‐based fat emulsion; the second group (n = 10) received olive oil ‐based fat emulsion. Body temperature, body mass index, (BMI) and biochemical variables were measured on days 0 and 7. There were no differences between the groups with regard to BMI or temperature. On day 7, the first group (compared with day 0) had significant increases in plasma alkaline phosphatase (81.70 ± 16.03 vs 117.60 ± 11.1), γ‐glutamyl transferase (39.90 ± 15.40 vs 137.70 ± 24.09), and mean body temperature (36.72°C ± 0.14°C vs 37.20°C ± 0.17°C) (P < .01). Second group had increases in alkaline phosphatase (85.80 ± 13.46 vs 147.20 ± 34.17), γ‐glutamyl transferase (48.40 ± 12.86 vs 129.40 ± 42.03), total protein (5.14 ± 0.19 vs 6.06 ± 0.49), and albumin (2.62 ± 0.14 vs 3.00 ± 0.18) (P < .05). Changes in thiobutyric acid levels were not statistically significant in either group. In postoperative cancer patients, olive oil‐based fat emulsion had similar effects on BMI, body temperature, biochemical values, and thiobutyric acid levels as soy oil‐based fat emulsions.

Cholesterol metabolism in pediatric short bowel syndrome after weaning off parenteral nutrition

BACKGROUND

Small intestine essentially regulates cholesterol homeostasis.

AIMS

To evaluate cholesterol metabolism in short bowel syndrome (SBS).

METHODS

Cholesterol precursors (e.g., cholestenol, desmosterol and lathosterol) and plant sterols (campesterol and sitosterol), respective markers of cholesterol synthesis and absorption, were determined in SBS patients (n=12) an average of 31 months after weaning off parenteral nutrition and in age-matched controls (n=80).

RESULTS

Among patients, serum cholesterol precursor sterol to cholesterol ratios were 2-10 times higher (P<0.0001 for each). Those without any remaining ileum had 1.2-2.8 times higher precursor sterol to cholesterol ratios than those with an ileal remnant (P<0.05 for each). Serum cholesterol concentration, campesterol/cholesterol and campesterol/sitosterol were 34-39% lower (P<0.05 for each) in relation to controls. Bile acid absorption was markedly impaired (2.4 (0.2-3.2)%). Plant sterol ratios reflected the absolute length of remaining jejunum (r=0.625-0.663), and precursor sterol ratios inversely that of ileum (r=-0.589 to 0.750, P<0.05 for all).

CONCLUSION

After weaning off parenteral nutrition, patients with pediatric onset SBS continue to have marked intestinal malabsorption of bile acids and moderate cholesterol malabsorption resulting in decreased serum cholesterol despite a marked compensatory increase in cholesterol synthesis.

Cholesterol, non-cholesterol sterols and bile acids in paediatric gallstones

BACKGROUND

Depending on underlying aetiopathogenetic factors human gallstones contain various amounts of cholesterol, non-cholesterol sterols and bile acids, which have remained unexplored in paediatric gallstone patients.

AIMS

To evaluate sterol and bile acids compositions of paediatric gallstones.

PATIENTS AND METHODS

Study group included 21 consecutively cholecystectomised children. Gas-liquid chromatography was used to quantitate gallstone sterols and bile acids. Results were compared to adult gallstones (n=194).

RESULTS

Cholesterol stones (n=9) had higher proportions of cholesterol and lathosterol, but lower those of lanosterol and phytosterols than pigment stones (n=12) (p<0.05 for each). Patients with gallstone cholesterol content over 70% were female. Gallstone cholesterol positively reflected body mass index and, in cholesterol stones-group, age (r=approximately +0.700, p<0.05). Three patients on parenteral nutrition had brown pigment stones consisting of high amounts of campesterol and sitosterol ranging 483-9303 microg/100 mg of stone. Pigment stones had 13-fold higher amount of bile acids than cholesterol stones (p<0.05). Black pigment stones contained approximately 3-fold higher phytosterol proportions, and pigment stones and cholesterol stones had approximately 43% lower proportions of deoxycholic acid than adults (p<0.05).

CONCLUSION

Gallstones in patients on parenteral nutrition are rich in phytosterols. With respect to gallstone sterols, gallstone disease of adolescent girls resembles that of adults. Composition of bile acids in paediatric gallstones is different from adults.

Recent advances in the management of intestinal failure-associated liver disease

PURPOSE OF REVIEW

To summarize the current management of intestinal failure-associated liver disease (IFALD) by reviewing recent advances in our understanding of the condition and the effects of different therapeutic approaches.

RECENT FINDINGS

The importance of gastrointestinal length and continuity in the aetiology and treatment of IFALD has been demonstrated in both retrospective and interventional cohorts. A mechanism for the cholestatic effect of soy-based lipid has been described, and the clinical use of alternative lipid sources has demonstrated benefit. Prevention of IFALD has been shown with the use of erythromycin in neonates, and reversal of established IFALD has been demonstrated with isolated intestinal transplantation.

SUMMARY

A greater understanding of the mechanisms of IFALD has led to promising interventions to prevent and treat the condition. Other possible therapeutic targets require more formal evaluation, and further work is required to develop noninvasive tools for the assessment and prognosis of IFALD that will guide treatment and help in the selection of patients and timing of transplantation.