Parenteral nutrition-associated liver complications in children

Low serum carnitine level is associated with increased urinary carnitine excretion in late pregnancy

BACKGROUND

Carnitine is essential for fatty acid metabolism. Free carnitine (FCA) is excreted in the urine in the glomerulus, but is partly reabsorbed by a carnitine transporter. The mechanism underlying the decrease in serum carnitine level during pregnancy is unclear.

OBJECTIVE

To investigate whether low carnitine level is associated with increased renal excretion in pregnant women.

METHODS

We recruited 43 healthy pregnant and 25 non-pregnant women. Total carnitine (TCA) and FCA levels were measured using the enzymatic cycling method, and the acylcarnitine (ACA) level was calculated. Fractional excretion (FE) was calculated as carnitine clearance divided by creatinine clearance.

RESULTS

The mean TCA, FCA, and ACA levels were lower at 12 weeks of gestation in pregnant than non-pregnant women (P < .001); the levels decreased further at 36 weeks, reaching 39%, 36%, and 52% of those in non-pregnant women, respectively (P < .001). The FEs were 3-4-fold higher in pregnant women than non-pregnant women. Pregnant women had a lower serum FCA/TCA ratio than non-pregnant women (0.788 ± 0.098 vs 0.830 ± 0.074, respectively; P < .05), whereas the urine FCA/TCA ratio was similar between the groups.

CONCLUSION

Low carnitine level is associated with increased renal excretion during late pregnancy.

Antenatal Growth, Gestational Age, Birth, Enteral Feeding, and Blood Citrulline Levels in Very Low Birth Weight Infants

Early enteral nutrition using reliable biomarkers of intestinal function must be established to improve neurodevelopmental outcomes in very low birth weight infants (VLBWIs). Serum citrulline levels reflect the intestinal function in adults. To elucidate the relationship among antenatal growth, postnatal enteral nutrition, and blood citrulline levels, a retrospective single-center observational study was conducted on 248 VLBWIs born between April 2014 and March 2021. A mixed effect model and post hoc simple slope analysis were used to estimate the correlations between clinical variables and citrulline levels at Early (day 5.1) and Late (day 24.3) postnatal ages. Greater gestational age, birth weight, and amount of enteral nutrition at the time of blood sampling were associated with lower citrulline levels at the Early postnatal age and higher citrulline levels at the Late postnatal age. Provided that Early citrulline levels predominantly reflect the consequence of antenatal citrulline metabolism, it is suggested that fetal growth and maturation are likely to promote citrulline catabolism in utero and its synthesis after birth. With additional insights into the temporal transition point wherein the maturation-dependent balance of citrulline metabolism shifts from catabolism-dominant to synthesis-dominant, citrulline emerges as a potential biomarker for assessing intestinal function and gastrointestinal disorders.

An Overview of Short-Bowel Syndrome in Pediatric Patients: Focus on Clinical Management and Prevention of Complications

Short-bowel syndrome (SBS) in pediatric age is defined as a malabsorptive state, resulting from congenital malformations, significant small intestine surgical resection or disease-associated loss of absorption. SBS is the leading cause of intestinal failure in children and the underlying cause in 50% of patients on home parental nutrition. It is a life-altering and life-threatening disease due to the inability of the residual intestinal function to maintain nutritional homeostasis of protein, fluid, electrolyte or micronutrient without parenteral or enteral supplementation. The use of parenteral nutrition (PN) has improved medical care in SBS, decreasing mortality and improving the overall prognosis. However, the long-term use of PN is associated with the incidence of many complications, including liver disease and catheter-associated malfunction and bloodstream infections (CRBSIs). This manuscript is a narrative review of the current available evidence on the management of SBS in the pediatric population, focusing on prognostic factors and outcome. The literature review showed that in recent years, the standardization of management has demonstrated to improve the quality of life in these complex patients. Moreover, the development of knowledge in clinical practice has led to a reduction in mortality and morbidity. Diagnostic and therapeutic decisions should be made by a multidisciplinary team that includes neonatologists, pediatric surgeons, gastroenterologists, pediatricians, nutritionists and nurses. A significant improvement in prognosis can occur through the careful monitoring of nutritional status, avoiding dependence on PN and favoring an early introduction of enteral nutrition, and through the prevention, diagnosis and aggressive treatment of CRSBIs and SIBO. Multicenter initiatives, such as research consortium or data registries, are mandatory in order to personalize the management of these patients, improve their quality of life and reduce the cost of care.

NF-κB Regulation of LRH-1 and ABCG5/8 Potentiates Phytosterol Role in the Pathogenesis of Parenteral Nutrition-Associated Cholestasis

BACKGROUND AND AIMS

Chronically administered parenteral nutrition (PN) in patients with intestinal failure carries the risk for developing PN-associated cholestasis (PNAC). We have demonstrated that farnesoid X receptor (FXR) and liver X receptor (LXR), proinflammatory interleukin-1 beta (IL-1β), and infused phytosterols are important in murine PNAC pathogenesis. In this study we examined the role of nuclear receptor liver receptor homolog 1 (LRH-1) and phytosterols in PNAC.

APPROACH AND RESULTS

In a C57BL/6 PNAC mouse model (dextran sulfate sodium [DSS] pretreatment followed by 14 days of PN; DSS-PN), hepatic nuclear receptor subfamily 5, group A, member 2/LRH-1 mRNA, LRH-1 protein expression, and binding of LRH-1 at the Abcg5/8 and Cyp7a1 promoter was reduced. Interleukin-1 receptor-deficient mice (Il-1r^-/- /DSS-PN) were protected from PNAC and had significantly increased hepatic mRNA and protein expression of LRH-1. NF-κB activation and binding to the LRH-1 promoter were increased in DSS-PN PNAC mice and normalized in Il-1r^-/- /DSS-PN mice. Knockdown of NF-κB in IL-1β-exposed HepG2 cells increased expression of LRH-1 and ABCG5. Treatment of HepG2 cells and primary mouse hepatocytes with an LRH-1 inverse agonist, ML179, significantly reduced mRNA expression of FXR targets ATP binding cassette subfamily C member 2/multidrug resistance associated protein 2 (ABCC2/MRP2), nuclear receptor subfamily 0, groupB, member 2/small heterodimer partner (NR0B2/SHP), and ATP binding cassette subfamily B member 11/bile salt export pump (ABCB11/BSEP). Co-incubation with phytosterols further reduced expression of these genes. Similar results were obtained by suppressing the LRH-1 targets ABCG5/8 by treatment with small interfering RNA, IL-1β, or LXR antagonist GSK2033. Liquid chromatography-mass spectrometry and chromatin immunoprecipitation experiments in HepG2 cells showed that ATP binding cassette subfamily G member 5/8 (ABCG5/8) suppression by GSK2033 increased the accumulation of phytosterols and reduced binding of FXR to the SHP promoter. Finally, treatment with LRH-1 agonist, dilauroyl phosphatidylcholine (DLPC) protected DSS-PN mice from PNAC.

CONCLUSIONS

This study suggests that NF-κB regulation of LRH-1 and downstream genes may affect phytosterol-mediated antagonism of FXR signaling in the pathogenesis of PNAC. LRH-1 could be a potential therapeutic target for PNAC.

ASPEN lipid injectable emulsion safety recommendations part 2: Neonate and pediatric considerations

Lipid injectable emulsions (ILEs) are complex pharmaceutical formulations intended as a source of energy and fatty acids for parenteral nutrition (PN) therapy. Part 1 of this series addressed issues associated with and safety recommendations pertaining to adult ILE use. Part 2 addresses ILE safety in neonatal and pediatric patients. Considerations for ILE use in the neonatal and pediatric populations differ from those of adults. For example, these patients often require higher doses compared with adult counterparts to support growth, development, and daily metabolic needs. ILE is also frequently administered as a separate infusion as opposed to in a total nutrient admixture owing to compatibility and stability issues and limitations to intravenous access in the neonatal and pediatric populations. ILE is the most frequent PN ingredient associated with PN errors occurring in the administration, prescribing, and transcribing processes. Concerns exist with use of in-line filters and repackaging of commercial products for infusion. ILE use in neonatal and pediatric patients has been associated with both minor and major adverse effects, which most often occur with doses exceeding manufacturer recommendations. Gaps in ILE best practices for neonatal and pediatric patients predispose to errors in the PN use system. This paper describes safe-use considerations for ILE products available in the United States in neonatal and pediatric patients, including indications, prescribing, order review, preparation, administration, and monitoring. This paper has been approved by the American Society for Parenteral and Enteral Nutrition (ASPEN) Board of Directors.

Vitamin D status in children with intestinal failure who have achieved enteral autonomy

BACKGROUND

Vitamin D deficiency is highly prevalent in children with intestinal failure (IF) who receive parenteral nutrition (PN), but data on vitamin D status after achieving enteral autonomy (EA) are limited. We aimed to evaluate the prevalence of vitamin D deficiency in this population while exploring clinical variables that may be associated with its development.

METHODS

A retrospective review was performed on 29 children with IF who had achieved EA. Deficiency was defined as a mean serum 25-hydroxyvitamin D <30 ng/ml.

DATA RESULTS

Sixty-six percent of children had at least one deficient level during the study period, with 38% being deficient based on the mean vitamin D levels. Eighty-four percent had radiologic evidence of osteopenia. Compared with the sufficient group (n=18), the deficient group (n=11) received higher daily mean vitamin D doses (2246 vs 920 IU; P=.02), had shorter remnant small-bowel length (53.8 vs 82.1 cm; P=.03), and were PN dependent for a longer duration (1.3 vs 0.58 years; P=.01). Univariate analyses revealed longer remnant gut length (odds ratio [OR] = 1.03; P=.04) and shorter duration of PN (OR = 0.26; P=.04) to be significantly associated with sufficient vitamin D status.

CONCLUSION

Vitamin D deficiency and osteopenia are highly prevalent in pediatric patients with a history of IF who have achieved EA, despite enteral supplementation with higher than standard doses. Shorter remnant small-bowel length and longer duration of PN were associated with vitamin D deficiency. These findings emphasize the importance of prolonged surveillance and highlight the need for alternate dosing regimens.

Elimination of hospital-acquired central line-associated bloodstream infection on a mixed-service pediatric unit

INTRODUCTION

Hospital-acquired central line-associated bloodstream infections (CLABSI) are "never events" in U.S. healthcare. National efforts to improve CLABSI rates are ongoing. Efforts are important for all patients with a central venous catheter (CVC) and critical to children with intestinal failure (IF) who depend on long-term, daily use of a CVC and undergo extended hospitalizations. We describe outcomes of a multidisciplinary CLABSI elimination effort on a 24-bed medical-surgical unit caring for children with IF.

METHODS

Unit CLABSI events from 1/9/2012 to 4/16/2020 were evaluated with multiple improvement interventions. We leveraged prospectively maintained clinical registries and National Healthcare Safety Network (NHSN) reporting data to extract patient and unit demographics, ethanol lock utilization, and unit CVC days. Interventions were developed utilizing expert consensus and CDC guidelines with active frontline staff engagement. Descriptive statistics and tests of non-parametric data were employed for analysis.

RESULTS

Ninety-five patients with IF and 862 non-IF patients experienced a total of 1,629 admissions with 20,372 CVC days. Twelve hospital-acquired CLABSI events occurred during the study period, including 7 following NHSN definition change on 1/1/2015 (0.56 per 1,000 CVC days). After the last unit CLABSI on 12/5/2016, there were 7,117 CVC days through study conclusion.

CONCLUSIONS

Described interventions with an enhanced culture of collaborative care profoundly improved hospital-acquired CLABSI occurrence. Success in a specific population translated to all other unit patients with a CVC. Findings suggest elimination is not the result of a single new product or practice, but also includes support and empowerment of those caring for the patient and their CVC.

An overview of the current management of short-bowel syndrome in pediatric patients

Short-bowel syndrome (SBS) is defined as a state of malabsorption after resection or loss of a major portion of the bowel due to congenital or acquired factors. This article presents an overview on the recent management of pediatric SBS. The pediatric SBS population is very heterogeneous. The incidence of SBS is estimated to be 24.5 per 100,000 live births. The nutritional, medical, and surgical therapies available require a comprehensive evaluation. Thus, multidisciplinary intestinal rehabilitation programs (IRPs) are necessary for the management of these complex patients. The key points of focus in IRP management are hepato-protective strategies to minimize intestinal failure-associated liver disease; the aggressive prevention of catheter-related bloodstream infections; strategic nutritional supply to optimize the absorption of enteral calories; and the management and prevention of small bowel bacterial overgrowth, nephrocalcinosis, and metabolic bone disease. As the survival rate of children with SBS currently exceeds 90%, the application of small bowel transplantation has been evolving. The introduction of innovative treatments, such as combined therapy of intestinotrophic hormones, including glucagon-like peptide-2, may lead to further improvements in patients' quality of life.

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.

Long-Term Outcomes and Disease Burden of Neonatal Onset Short Bowel Syndrome

PURPOSE

The study aims to describe long-term outcomes and disease burden of neonatal onset short bowel syndrome (SBS).

METHODS

Utilizing the WHO criteria for adolescence, patients 10-19 years of age with neonatal onset SBS requiring parenteral nutrition (PN) for >90 days and followed by our multidisciplinary intestinal rehabilitation center between 2009 and 2018 were included for analysis.

RESULTS

Seventy adolescents with SBS were studied. Median (IQR) age at last follow up in our center was 15 (11, 17) years. There was 0% mortality in the cohort, and 94% remained transplant free. Fifty-three patients (76%) achieved enteral autonomy. Three patients were weaned from PN without transplantation after six years of follow-up and another four after ten years of care at our multidisciplinary center. Disease burden remained higher in adolescents receiving PN, including inpatient hospitalizations (p < 0.01), procedures (p = 0.01), clinic visits (p < 0.01), and number of prescribed medications (p < 0.01).

CONCLUSION

Survival for adolescents with neonatal onset SBS is excellent. Of the cohort studied, there was no mortality, and more than 75% achieved enteral autonomy. Disease burden remains high for adolescents who remain dependent on PN. However, achievement of enteral autonomy is feasible with long-term multidisciplinary rehabilitation.

TYPE OF STUDY

Prognosis study.

LEVEL OF EVIDENCE

Level II.

Parenteral Nutrition Complications in Children Undergoing Bone Marrow Transplantation

BACKGROUND

Parenteral nutrition (PN) seems to be a practical solution to face the negative nutritional effects of bone marrow transplantation.

OBJECTIVE

Report and describe all observed PN-related complications in children undergoing allogenic bone marrow transplantation in a tertiary center and determine the possible risk factors.

MATERIALS AND METHODS

This was a retrospective and observational study including 51 allografted children 2 to 17 years of age. We collected from medical patient records any noticed PN-related complications using an assessment causality method. The independent risk factors for complications were investigated by multivariate analysis.

RESULTS

A total of 92% of patients (n=47) developed a total of 136 complications attributable to PN. The incidence rate of complications was 5 for 100 patient days of PN. Infectious complications (32.3%) and electrolytic disorders (27.9%) were the most common conditions identified during our study. Multivariate analysis showed that the duration of PN exposure, age, and hyperglycemia were the risk factors for the onset of these complications.

CONCLUSIONS

Although we have noticed multiple complications attributable to PN, a certain causal link is difficult to establish in this particular context. Emphasizing enteral nutrition in bone marrow graft protocols would be the best way to avoid these complications.

[Levels of blood free carnitine in preterm infants with different gestational ages and birth weights]

OBJECTIVE

To examine blood concentrations of free carnitine (FC) in preterm infants with different gestational ages (GA) and birth weights (BW).

METHODS

A total of 3 368 preterm infants were enrolled as subjects. According to GA, they were divided into extremely preterm birth (EPTB) group (GA <28 weeks; n=39), very preterm birth (VPTB) group (28 ≤GA <32 weeks; n=405), moderately preterm birth (MPTB) group (32 ≤GA <34 weeks; n=507), and late preterm birth (LPTB) group (34 ≤GA <37 weeks; n=2 417); according to BW, they were divided into extremely low birth weight (ELBW) group (BW <1 000 g; n=36), very low birth weight (VLBW) group (1 000 g ≤BW <1 500 g; n=387), low birth weight (LBW) group (1 500 g ≤BW <2 500 g; n=1 873), and normal birth weight (NBW) group (2 500 g ≤ BW <4 000 g; n=1 072). Blood concentrations of FC were measured between 72 hours and 7 days after birth.

RESULTS

The EPTB and VPTB groups had significantly higher FC concentrations than the MPTB and LPTB groups (P<0.05), and the MPTB group had significantly higher FC concentrations than the LPTB group (P<0.05). The lower limit of the 95% medical reference range of FC increased with the reduction in GA. The ELBW and VLBW groups had significantly higher FC concentrations than the LBW and NBW groups (P<0.05). The LBW group had significantly higher FC concentrations than the NBW group (P<0.05). The lower limit of the 95% medical reference range of FC increased with the reduction in BW.

CONCLUSIONS

There is a significant increase in blood FC concentrations in very/extremely preterm infants and very/extremely low birth weight infants, and tend to decrease with the increases in GA and BW.

Predictive value of the aspartate aminotransferase to platelet ratio index for parenteral nutrition associated cholestasis in extremely low birth weight infants

Background

Parenteral nutrition (PN) improves the survival of premature infants. However, prolonged PN increases the risk of PN-associated cholestasis (PNAC).

Objective

We aimed to evaluate the predictive value of aspartate aminotransferase (AST)-to-platelet ratio index (APRI) for PNAC in infants with extremely low birth weight (ELBW, birth weight < 1000 g) infants.

Methods

We retrospectively reviewed the medical records of ELBW infants from March 2010 to February 2017. Clinical data and the serial APRI, AST, alanine aminotransferase (ALT), AST-to-ALT ratio, and direct bilirubin (DB) were analyzed. PNAC was diagnosed in infants with a history of PN for at least 2 weeks and direct bilirubin concentrations > 2 mg/dL after other causes of neonatal cholestasis were excluded.

Results

Among the 179 eligible ELBW infants, 56 (31.3%) were diagnosed with PNAC. APRI significantly differed between infants with PNAC and those without PNAC. The best APRI cut-off point was 0.410 at 2 weeks after the start of PN (area under the receiver operating characteristic curve = 0.752, p < 0.05; positive predictive value, 50.6%; negative predictive value, 84.1%).

Conclusion

APRI at 2 weeks after PN could be a reliable predictor of PNAC development in ELBW infants on PN.

Two parenteral amino acid solutions and plasma levels of amino acids in the neonate: A randomized trial

OBJECTIVE

In neonates on total parenteral nutrition (TPN), amino acids may be a risk factor for developing total parenteral nutrition-associated cholestasis (TPNAC). We aimed, first, to compare methionine, cysteine, and taurine plasma levels between neonates on TPN who were receiving an intravenous amino acid solution based on a breast milk aminogram and those on an intravenous solution of pediatric amino acids based on an umbilical cord aminogram, and second, to determine the frequency of TPNAC.

METHODS

A double-blind randomized controlled trial was conducted. Ninety-four neonates with a birthweight of 1000g or more and a gestational age of 30 wk or older were admitted and enrolled. Blood samples were obtained at 0, 7, and 14 d of TPN, and plasma amino acid concentrations were determined by ultra-high-resolution liquid chromatography. Continuous variables were compared using the Wilcoxon rank-sum test or Student's t test; categorical variables were compared using the Fisher exact test.

RESULTS

Thirty-five neonates completed the study (Primene, n = 14; TrophAmine, n = 21). On day 14, methionine plasma concentrations were significantly lower in the Primene group than in the TrophAmine group (27 µmol/L versus 32.9 µmol/L, P = 0.044); the taurine concentration was significantly higher in the same group (72.4 µmol/L versus 45.3 µmol/L, P < 0.0001). There were no differences in TPNAC incidence.

CONCLUSIONS

Administering an intravenous solution of pediatric amino acids based on the umbilical cord aminogram yielded a higher taurine and lower methionine plasma concentration than did administering a similar solution based on the breast milk aminogram.

Neonatal Cholestasis

Neonatal jaundice is common and usually not concerning when it is secondary to unconjugated hyperbilirubinemia, below the neurotoxic level, and resolves early. Primary care providers should be vigilant, however, about evaluating infants in whom jaundice presents early, is prolonged beyond 2 weeks of life, or presents at high levels. Even in well-appearing infants, fractionated (direct and indirect) bilirubin levels should be obtained in these clinical scenarios to evaluate for potential cholestasis. This review presents an approach to the evaluation of a jaundiced infant and discusses diagnosis and management of several causes of neonatal cholestasis.

Retrospective Dual-Center Study of Parenteral Nutrition-Associated Cholestasis in Premature Neonates: 15 Years' Experience

BACKGROUND

The pathogenesis of parenteral nutrition-associated cholestasis (PNAC) has not been clarified. The objective of this study was to explore the incidence of PNAC in premature infants without surgery and to identify associated risk factors.

MATERIALS AND METHODS

Premature neonates who received parenteral nutrition (PN) at least 14 days were included in a retrospective, dual-center study. Cholestasis was diagnosed as conjugated bilirubin ≥2 mg/dL. Infants with metabolic liver disease, cyanotic congenital heart disease, congenital syphilis, hepadnaviridae infection, and those who underwent surgery were excluded. Infants were divided into 3 groups chronologically: group A (2000-2004, n = 50), group B (2005-2009, n = 283), and group C (2010-2014, n = 741). A case-controlled study was conducted by comparing infants with PNAC to those without PNAC.

RESULTS

Of 1074 premature neonates, PNAC was confirmed in 53 infants (4.93%). There were 6.8% very low birth weight (BW) infants and 20.0% extremely low BW infants who developed PNAC. The incidence of PNAC decreased slightly during 2000-2014 (8.0%, 6.4%, and 4.2% in groups A, B, and C, respectively). Compared with those without PNAC, infants with PNAC (n = 53) had significantly younger gestational age, lower BW, longer PN duration, and higher rate of sepsis. Logistic regression showed male sex, PN duration ≥43 days, and sepsis were statistically correlated with PNAC.

CONCLUSIONS

Prolonged duration (≥43 days), male sex, and sepsis are probably independent risk factors for developing PNAC in premature neonates.

Vanishing Bowel: A Therapeutic Challenge

"Vanishing bowel" has been rarely reported in the literature. This case and discussion are intended to describe the surgical, medical, and nutrition management of this unusual congenital abnormality. Of 3 reported cases surviving vanishing bowel, one had substantial residual small bowel, another had residual small bowel and bowel-lengthening procedure, and one received an intestinal liver transplant. The patient presented in this case had residual small bowel and lengthening procedure. The patient described is well as of October 2005 (age 3.5 years), still receiving nocturnal parenteral nutrition (PN), but is eating solid foods without significant malabsorption or abdominal distention. He has experienced modest weight gain over the past 2 months.

Principles and Strategies for Monitoring Home Parenteral Nutrition

Patients who cannot ingest adequate calories to maintain body weight via their gastrointestinal tract may require parenteral nutrition (PN) at home. As with any therapy, the patient must be evaluated to determine if the home PN (HPN) is effective and the patient is free of complications. This review discusses specific items to monitor for HPN patients. Parameters to monitor can be divided into those used to determine effectiveness and those used to prevent complications of HPN. In addition, potential HPN-associated complications can be divided into those that occur with short- or long-term PN administration. Specific items to monitor are discussed within this framework.

Risk factor analysis of parenteral nutrition-associated cholestasis in extremely low birth weight infants

AIM

Parenteral nutrition (PN) provides an alternative nutrition source for preterm infants who are intolerant of enteral nutrition. However, prolonged PN increases the risk of PN-associated cholestasis (PNAC). We conducted this study to determine the incidence and risk factors of PNAC in extremely low birth weight (ELBW) infants.

METHODS

We retrospectively reviewed the medical records of ELBW infants from March 2010 to April 2015. PNAC was diagnosed in infants with a history of PN for at least two weeks and direct bilirubin concentrations >2 mg/dL after other causes of neonatal cholestasis were excluded.

RESULTS

Of the 114 eligible ELBW infants, 41 (36%) were diagnosed with PNAC. The multivariate analysis showed that birth weight, sepsis, necrotising enterocolitis, fluconazole prophylaxis and the duration of PN and hospitalisation were independent risk factors for the development of PNAC (p < 0.05). However, parenteral fish oil-based lipid preparation (FOLP) did not reduce the risk of PNAC. Although PNAC was not a direct cause of death, it was associated with an increased risk of mortality.

CONCLUSION

PNAC was common in ELBW infants, was associated with various clinical factors and increased the risk of mortality. However, we did not observe the protective effect of FOLP against PNAC.

Cholestasis in Preterm Infants

Cholestasis in preterm infants has a multifactorial etiology. Risk factors include degree of prematurity, lack of enteral feeding, intestinal injury, prolonged use of parenteral nutrition (PN), and sepsis. Soy-based parenteral lipid emulsions have been implicated in the pathophysiology of PN-associated liver injury. Inflammation plays an important role. Medical therapies are used; however, their effects have not consistently proven effective. Evaluation of cholestasis involves laboratory work; direct bilirubin levels are used for diagnosis and trending. Adverse outcomes include risk for hepatobiliary dysfunction, irreversible liver failure, and death. Early enteral feedings as tolerated is the best way to prevent and manage cholestasis.

Ethanol Lock Efficacy and Associated Complications in Children With Intestinal Failure

BACKGROUND

Prophylactic ethanol lock therapy (ELT) reduces central line-associated bloodstream infections (CLA-BSIs) in children with intestinal failure (IF). However, the risk of associated complications is unclear. We aim to describe our experience with prophylactic ethanol locks in a cohort of patients with IF.

MATERIALS AND METHODS

Thirty patients on ELT from 2010-2013 were identified by review of our intestinal rehabilitation registry. Patient demographics, CLA-BSI events, and line complications were extracted. Comparisons in infection and complication rates when on and off ELT were made using a Poisson mixed-effect regression model.

RESULTS

CLA-BSIs when on and off ELT were 3.1 and 5.5 per 1000 catheter days, respectively (P <015). Overall complication rates were similar in both groups. In those patients who experienced a complication, the complication rates on ELT compared with time off ELT were significantly lower (P <003). Line perforation or breakage rates declined significantly when on ELT, from 1.8 to 1.53 per 1000 catheter days (P <006). Line occlusion rates also decreased on ELT, from 0.6 to 0.3 per 1000 catheter days (P =056). Infecting organisms were not different on and off ELT, and patients experienced a similar number of polymicrobial infections on or off therapy. Klebsiella pneumoniae was the most common infecting organism in both groups.

CONCLUSIONS

Ethanol lock therapy use reduces both CLA-BSI and central line complication rates in children with IF. These results underscore the safety and efficacy of ELT use in this population.

Recent advances in the management of pediatric intestinal failure

Intestinal failure is a chronic condition in which the intestinal tract has lost most of its function. Prognosis depends on the severity and underlying etiologies. Although many patients survive under parenteral nutrition support, they often suffer from fatal complications such as progressive cholestasis and frequent sepsis. In addition, to decide the proper time to refer selected patients to bowel transplantation remains difficult. A noninvasive biomarker developed to evaluate functional enterocyte mass and the extent of intestinal adaptation is plasma citrulline level. It is shown that serum citrulline correlates with small bowel length, oral tolerance, and parenteral nutrition dependency. Recent evidence has revealed that the use of fish oil containing lipid emulsions to substitute traditional soybean-based formula may reverse a patient's cholestasis and improve lipid profiles. A new method used to prevent catheter-related bloodstream infection is ethanol lock therapy. With both antimicrobial and fibrinolytic activities, studies have shown that ethanol locks can effectively decrease catheter infection and replacement rate with no known resistance reported. As part of intestinal rehabilitation, auxiliary surgeries such as longitudinal intestinal lengthening and tailoring, serial transverse enteroplasty, and tapering enteroplasty can be beneficial for selected patients before bridging to bowel transplantation. With the introduction of these new medical and surgical modalities, patients with intestinal failure are having better outcomes than in the past.

Specific microbiome changes in a mouse model of parenteral nutrition associated liver injury and intestinal inflammation

BACKGROUND

Parenteral nutrition (PN) has been a life-saving treatment in infants intolerant of enteral feedings. However, PN is associated with liver injury (PN Associated Liver Injury: PNALI) in a significant number of PN-dependent infants. We have previously reported a novel PNALI mouse model in which PN infusion combined with intestinal injury results in liver injury. In this model, lipopolysaccharide activation of toll-like receptor 4 signaling, soy oil-derived plant sterols, and pro-inflammatory activation of Kupffer cells (KCs) played key roles. The objective of this study was to explore changes in the intestinal microbiome associated with PNALI.

METHODOLOGY AND PRINCIPAL FINDINGS

Microbiome analysis in the PNALI mouse identified specific alterations within colonic microbiota associated with PNALI and further association of these communities with the lipid composition of the PN solution. Intestinal inflammation or soy oil-based PN infusion alone (in the absence of enteral feeds) caused shifts within the gut microbiota. However, the combination resulted in accumulation of a specific taxon, Erysipelotrichaceae (23.8% vs. 1.7% in saline infused controls), in PNALI mice. Moreover, PNALI was markedly attenuated by enteral antibiotic treatment, which also was associated with significant reduction of Erysipelotrichaceae (0.6%) and a Gram-negative constituent, the S24-7 lineage of Bacteroidetes (53.5% in PNALI vs. 0.8%). Importantly, removal of soy oil based-lipid emulsion from the PN solution resulted in significant reduction of Erysipelotrichaceae as well as attenuation of PNALI. Finally, addition of soy-derived plant sterol (stigmasterol) to fish oil-based PN restored Erysipelotrichaceae abundance and PNALI.

CONCLUSIONS

Soy oil-derived plant sterols and the associated specific bacterial groups in the colonic microbiota are associated with PNALI. Products from these bacteria may directly trigger activation of KCs and promote PNALI. Furthermore, the results indicate that lipid modification of PN solutions may alter specific intestinal bacterial species associated with PNALI, and thus suggest strategies for management of PNALI.

Glucagon-Like Peptide 2 Improves Cholestasis in Parenteral Nutrition--Associated Liver Disease

BACKGROUND

Parenteral nutrition-associated liver disease (PNALD) remains a significant cause of morbidity and mortality in neonates with intestinal failure. Although glucagon-like peptide-2 (GLP-2) is being advanced as therapy, the effect of GLP-2 treatment on PNALD is unknown. We aim to investigate the effect of exogenous GLP-2 administration on hepatic function in a neonatal piglet model of PNALD.

METHODS

Neonatal piglets (aged 2-6 days) underwent jugular venous catheterization to receive isonitrogenous, isocaloric parenteral nutrition (PN). Piglets were allocated to 2 groups: group 1 (n = 8) received saline while group 2 (n = 7) received GLP-2 (at 11 nmol/kg/d). After 17 days, piglets underwent terminal laparotomy, and bile flow was measured. Liver specimens were analyzed histologically and with immunoperoxidase staining. Age-matched sow-reared control piglets (group 3, n = 8) were used for comparison.

RESULTS

Both groups 1 and 2 receiving PN developed cholestasis relative to sow-reared controls, as evidenced by a decrease in bile flow and increase in serum total bilirubin. However, group 2 had improved bile flow (1.35 vs 0.73 µL/g; P = .02) and diminished bilirubin (38.0 vs 78.5 µmol/L; P = .008) compared with group 1. Group 2 also had lower serum alanine aminotransferase levels, a marker of liver injury. Histologically, the liver specimens in group 1 had marked hepatocyte pigmentation, which was decreased in group 2 specimens.

CONCLUSIONS

The exogenous administration of GLP-2 is associated with the improvement of cholestasis and liver injury. This study introduces a novel role for GLP-2 in improving PNALD in the setting of prolonged PN duration.

Analysis of bile in various hepatobiliary disease states: A pilot study

AIM

Our study aims to find various enzymatic and biochemical components of bile and their clinical or prognostic correlation with regard to progression and severity of hepatobiliary diseases.

MATERIALS AND METHODS

It was a cross-sectional study where all the patients suffering from choledochal cyst (CDC), extrahepatic portal venous obstruction (EHPVO), and infantile obstructive cholangiopathy undergoing diagnostic preoperative cholangiogram; and patients with history of total parenteral nutrition (TPN) undergoing surgery for some other condition were included in the study. Intraoperatively, bile was collected from the gallbladder and sent for estimation of amylase, lipase, sodium, potassium, calcium, chloride, bicarbonate, total bilirubin, pH, cholesterol, triglycerides, and total bile acid.

RESULTS

A total of 80 patients were included in the study (20 in each of the four disease-based groups). Amylase, lipase, and pH were significantly different among the patients of CDC when compared with the presence or absence of dilated intrahepatic biliary radicals. Similarly, amylase, lipase, and pH were also significantly different among the patients of EHPVO when compared with presence or absence of biliopathy. Levels of cholesterol and bile acid were significantly higher in patients who were evaluated after 1 year following TPN than those who were evaluated before 1 year. The patients of infantile cholangiopathy, who had history of fever, had significantly higher level of calcium.

CONCLUSION

The components of bile show close correlation with various clinical and prognostic markers, there is a very close correlation between these parameters and the clinical severity, disease progression, and final outcome.

Complications associated with parenteral nutrition in the neonate

Although parenteral nutrition (PN) is life-sustaining, it is associated with many complications including parenteral nutrition-associated liver disease (PNALD) and central line-associated bloodstream infections (CLASBIs), which carry a high morbidity and mortality and impose a burden on the health care system. Evidence has emerged that the dose and composition of intravenous lipid products may alter the incidence of PNALD. However, other patient and PN-related factors, such as prematurity, birth weight, and gastrointestinal anatomy and function, are important. To improve neonatal care, future research on optimizing the content of PN and decreasing the incidence IFALD and CLASBIs is required.

Parenteral nutrition-associated liver disease: a retrospective study of ursodeoxycholic Acid use in neonates

OBJECTIVES

To verify the effect of ursodeoxycholic acid (UDCA) on the duration of neonatal parenteral nutrition-associated liver disease.

METHODS

Retrospective cohort study of neonates in intensive care between 2004 and 2007 presenting with parenteral nutrition-associated liver disease.

RESULTS

Of 118 eligible infants, 64 received UDCA. Cholestasis lasted longer in the UDCA group (79 vs. 50 days, p=0.001). However, treatment was delayed for a median of 24 days after cholestasis onset. Multivariate Cox regression analysis showed no association between UDCA and cholestasis duration. The rate of decline of conjugated bilirubin was greater in treated patients (median 0.084 mg/dL/day vs. 0.60 mg/dL/day; p=0.009) and weight gain was greater (22.8 vs. 17.7 g/kg/day, p=0.010).

CONCLUSIONS

UDCA therapy was not associated with the duration of parenteral nutrition-associated liver disease. A delay in treatment initiation might explain this result. UDCA therapy was associated with a faster decline of conjugated bilirubin and greater weight gain.

Total parenteral nutrition-associated cholestasis and risk factors in preterm infants

BACKGROUND/AIM

Development of hepatic dysfunction is a well-recognized complication of total parenteral nutrition in preterm infants. Previous studies reported the incidence of total parenteral nutrition-associated cholestasis and described possible contributing factors to its pathogenesis, but little is done trying to determine its possible predictive risk factors. The aims of this study was to determine the incidence of total parenteral nutrition-associated cholestasis and to develop a possible predictive model for its occurrence.

PATIENTS AND METHODS

A review of medical records of all very low birth weight infants admitted to neonatal intensive care unit at King Khalid University Hospital, Riyadh, Saudi Arabia, between January 2001 and December 2003 was carried out. The infants were divided into two groups: Cholestasis and noncholestasis, based on direct serum bilirubin level >34 μmol/L. A multivariate logistic regression analysis was performed to calculate the statistical significance of risk factors. Receiver-operating characteristic curve was used to determine the optimal cutoff points for the significant risk factors and to calculate their sensitivity and specificity. The level of significance was set at P ≤ 0.05.

RESULTS

A total of 307 patients were included in the analysis. The incidence of cholestasis in the whole population was 24.1% (74 patients). Infants with cholestasis had a lower birth weight, 735.4 ± 166.4 g vs. 1185.0 ± 205.6 g for noncholestasis group (P < 0.001), whereas the mean gestational age for the two groups was 25.4 ± 2.1 week and 28.9 ± 2.1 week, respectively (P < 0.001). The significant risk factors for the development of cholestasis were birth weight (P = 0.006) with an odds ratio of 0.99 [95% confidence interval (CI), 0.98, 0.99]; sensitivity of 92%, specificity of 87%; and total parenteral nutrition duration (P < 0.001) with an odds ratio of 1.18 (95% CI, 1.10, 1.27); sensitivity of 96%, specificity of 89%.

CONCLUSIONS

A lower birth weight and longer duration of total parenteral nutrition were strong predictive risk factors for the development of cholestasis in preterm infants.

Parenteral nutrition associated cholestasis is earlier, more prolonged and severe in small for gestational age compared with appropriate for gestational age very low birth weight infants

PURPOSE

We hypothesized that parenteral nutrition associated cholestasis (PNAC) would be more severe in small for gestational age (SGA) compared with appropriate for gestational age (AGA) very low birth weight (VLBW) infants.

MATERIALS AND METHODS

Sixty-one VLBW infants were diagnosed as PNAC with exposure to parenteral nutrition with elevation of direct bilirubin≥2 mg/dL for ≥14 days. Twenty-one SGA infants and 40 AGA infants matched for gestation were compared.

RESULTS

Compared with AGA infants, PNAC in SGA infants was diagnosed earlier (25±7 days vs. 35±14 days, p=0.002) and persisted longer (62±36 days vs. 46±27 days, p=0.048). Severe PNAC, defined as persistent elevation of direct bilirubin≥4 mg/dL for more than 1 month with elevation of liver enzymes, was more frequent in SGA than in AGA infants (61% vs. 35%, p=0.018). The serum total bilirubin and direct bilirubin levels during the 13 weeks of life were significantly different in SGA compared with AGA infants. SGA infants had more frequent (76% vs. 50%, p=0.046), and persistent elevation of alanine aminotransferase.

CONCLUSION

The clinical course of PNAC is more persistent and severe in SGA infants. Careful monitoring and treatment are required for SGA infants.

Intestinal transplantation: a review

Parenteral nutrition is a life-saving therapy for patients with intestinal failure. Intestinal transplantation is now recognized as a treatment for patients who develop complications of parenteral nutrition and in whom attempts at intestinal rehabilitation have failed. Patients with parenteral nutrition related liver disease will require a liver graft typically part of a multivisceral transplant. Isolated intestinal transplants are more commonly performed in adults while multivisceral transplants are most commonly performed in infants. Isolated intestinal transplants have the best short-term outcome, with over 80 % survival at 1 year. Patients requiring multivisceral transplants have a high rate of attrition with a 1 year survival less than 70 %. Prognostic factors for a poor outcome include patient hospitalization at the time of transplant and donor age greater than 40 years while systemic sepsis and acute rejection are the major determinant of early postoperative outcome. For patients surviving the first year the outcome of transplantation of the liver in addition to intestine affords some survival advantage though long-term outcome does not yet match other abdominal organs. Outcomes for intestinal retransplantation are poor as a result of immunology and patient debility. Overall intestinal transplantation continues to develop and is a clear indication with cost and quality of life advantages in patients with intestinal failure that do not remain stable on parenteral nutrition.

Safety and role of ketogenic parenteral nutrition for intractable childhood epilepsy

To retrospectively evaluate the safety and role of ketogenic parenteral nutrition in patients with intractable childhood epilepsy. The ketogenic parenteral nutrition was given to 10 patients who were unable to absorb nutrients through the intestinal tract because of various gastrointestinal disorders and required complete bowel rest. This nutrition consisted of conventional intravenous fat emulsion (20% Lipision) plus dextrose and amino acid (6% Trophamine) hyperalimentation in a 4:1 (or 3:1) lipid to non-lipid ratio, infused during the bowel rest. If the ketogenic parenteral nutrition allowed normal daily functioning or resolved the underlying problems, we soon changed it to the enteral ketogenic diet (KD). The mean (±SD) duration of the ketogenic parenteral nutrition was 4.1 (±1.5) days. Although a brief span of several days, all patients could maintain ketosis and the efficacy of the previous enteral KD during the ketogenic parenteral nutrition. Complications included elevated aspartate aminotransferase and/or alanine aminotransferase in one patient. Amylase and lipase increased in one patient. Serum triglyceride level increased to the level of 1885 mg/dl in one patient, but normalized in one week after discontinuation of the ketogenic parenteral nutrition and resuming of the enteral KD. Nine patients (90%) remained on the enteral KD after the ketogenic parenteral nutrition (the mean follow-up period was 9 months), including 2 patients who successfully completed the diet with seizure free state. Only one patient discontinued the ketogenic parenteral nutrition because of persistent increase of the amylase and lipase levels. The ketogenic parenteral nutrition proved to be a relatively safe short-term method of continuing KD to maintain ketosis for seizure control, while patients were unable to absorb nutrients through their intestinal tract.

Provision of a soy-based intravenous lipid emulsion at 1 g/kg/d does not prevent cholestasis in neonates

BACKGROUND

One of the most common and severe complications of long-term parenteral nutrition (PN) is PN-associated cholestasis. The soybean oil-based lipid emulsion administered with PN has been associated with cholestasis, leading to an interest in lipid reduction strategies. The purpose of this study was to determine whether the provision of a soybean oil-based lipid emulsion at 1 g/kg/d compared with 2-3 g/kg/d is associated with a reduced incidence of cholestasis.

METHODS

Retrospective review of neonates admitted between 2007 and 2011 with a gastrointestinal condition necessitating ≥ 21 days of PN support. Neonates were divided into 2 groups based on the intravenous lipid emulsion dose: 1-g group (1 g/kg/d) and 2- to 3-g group (2-3 g/kg/d). The primary outcome measure was the incidence of cholestasis.

RESULTS

Sixty-one patients met inclusion criteria (n = 29, 1-g group; n = 32, 2- to 3-g group). The 2 groups did not differ in any baseline characteristics other than associated comorbidities that were more common in the 2- to 3-g group. The duration of PN, the number of operative procedures and bloodstream infections, and enteral nutrition (EN) were similar between groups. The incidence of cholestasis was not different between groups (51.7%, 1-g group; 43.8%, 2- to 3-g group; P = .61), and there was no difference between groups in the time to cholestasis (32.6 ± 24.1 days, 1-g group; 27.7 ± 10.6 days, 2- to 3-g group; P = .48). Overall, 44.8% of patients with cholestasis were transitioned to full EN, and 55.2% were transitioned to a fish oil-based lipid emulsion after which the direct bilirubin normalized in all patients.

CONCLUSION

Lipid reduction to 1 g/kg/d does not prevent or delay the onset of cholestasis in neonates.

Short bowel syndrome in children: current and potential therapies

Short bowel syndrome (SBS) reflects a state of malabsorption that occurs due to loss of a significant portion of the small bowel. The pathophysiology of SBS is determined largely by the process of adaptation, which is the innate attempt by the remnant portions of the intestine to increase fluid and nutrient reabsorption. In recent years, emphasis has been placed on intestinal rehabilitation with multidisciplinary teams as a comprehensive approach to the management of patients with SBS. In our institution, the multidisciplinary team members include pediatric gastroenterologists, pediatric surgeons, pediatric dieticians, physical therapists, occupational therapists, neonatologists (especially for patients still under their care), transplant surgeons, transplant coordinators and social workers. Parenteral nutrition plays a significant role in the management of SBS, but its use is associated with many potential complications, including cholestatic liver disease. Fish oil-based lipid emulsions have shown promise in their ability to reverse and also prevent the development of cholestasis in these patients. Clinical trials have shown that growth factors and other trophic hormones facilitate the process of adaptation. The most significant impact has been shown with the use of glucagon-like peptide-2 and its analog (teduglutide). Surgical interventions remain an important part of the management of SBS to facilitate adaptation and treat complications. Intestinal transplantation is a last resort option when the process of adaptation is unsuccessful. This review article is intended to provide an overview of the conventional and emerging therapies for pediatric SBS.

Intestinal failure-associated liver disease in surgical infants requiring long-term parenteral nutrition

PURPOSE

Our aim was to determine incidence, severity, and outcome, as well as predisposing factors and underlying diagnoses, of intestinal failure-associated liver disease (IFALD) in surgical infants requiring long-term parenteral nutrition (PN).

METHODS

We retrospectively studied surgical infants receiving PN for at least 28 days for congenital or acquired intestinal anomalies over a 5-year period (January 2006 to December 2010). Intestinal failure-associated liver disease was defined as type 1 (early)--persistent elevation of alkaline phosphatase for 6 weeks or longer; type 2 (established)--additional elevated total bilirubin (≥ 50 μmol/L); and type 3 (late)--additional clinical signs of end-stage liver disease.

RESULTS

Eighty-seven infants required PN for at least 28 days. Intestinal failure-associated liver disease occurred in 29 infants (33%). Intestinal failure-associated liver disease was managed medically in all but 2 patients who underwent intestinal elongation. None were referred for intestinal or liver transplant. Intestinal failure-associated liver disease has been reversed in 17 (59%) of cases to date. Sixty-one children receiving long-term PN (70%) have achieved enteral autonomy, whereas 12 (14%) require home PN. Severity of IFALD was significantly associated with duration of PN and female sex.

CONCLUSION

Intestinal failure-associated liver disease remains a fairly common but rarely life-threatening complication of intestinal failure in surgical infants. Intestinal failure-associated liver disease can be reversed in more than half of these children, and enteral autonomy was achieved in more than two thirds, even with minimal use of intestinal elongation. This is the first study to demonstrate an association between the severity of IFALD in surgical infants and female sex.

Anti-tumor necrosis factor-α monoclonal antibody alleviates parenteral nutrition-associated liver disease in mice

BACKGROUND

The authors aimed to investigate the role of anti-tumor necrosis factor (TNF)-α monoclonal antibody treatment in a mouse model of parenteral nutrition-associated liver disease (PNALD).

METHODS

C57BL/6J male mice (aged 6-8 weeks) were randomly assigned to 3 groups: parenteral nutrition (PN), PN with anti-TNF-α monoclonal antibody treatment (PN + mAb), and controls. A central venous catheter was inserted for intravenous infusion of a PN solution (PN and PN + mAb groups) or saline (controls) for 7 days. Liver pathology, hepatic biochemical indicators, and serum TNF-α concentrations were analyzed. Levels of hepatic bsep, mdr1a/mdr1b, mdr2, and mrp2 mRNA were also evaluated in each group.

RESULTS

The PN group showed significant increases in serum transaminase, direct bilirubin, and bile acids relative to the control group (P < .05). Histopathological changes in this group were consistent with early stage cholestasis. The pathological score and serum alanine aminotransferase, total bilirubin, and direct bilirubin levels were improved in the PN + mAb group relative to the PN group (P < .05). The PN group showed significantly lower hepatic bsep, mdr1a/mdr1b, mdr2, and mrp2 mRNA expression than the controls (P < .05), but these were significantly increased compared to the PN group (P < .05).

CONCLUSIONS

Infliximab administered at a single dose of 5 mg/kg body weight ameliorated the progression of PNALD and improved the expression of hepatic ABC transporter genes. Therefore, anti-TNF-α monoclonal antibody may be a beneficial therapy for patients with PNALD.

Risk factors for parenteral nutrition–associated liver disease following surgical therapy for necrotizing enterocolitis: A Glaser Pediatric Research Network Study [corrected]

OBJECTIVE

The aim of the study was to prospectively determine risk factors for the development of parenteral nutrition-associated liver disease (PNALD) in infants who underwent surgery for necrotizing enterocolitis (NEC), the most common cause of intestinal failure in children.

PATIENTS AND METHODS

: From February 2004 to February 2007, we diagnosed 464 infants with NEC, of whom 180 had surgery. One hundred twenty-seven patients were available for full analysis. PNALD was defined as serum direct bilirubin ≥ 2 mg/dL or ALT ≥ 2 × the upper limit of normal in the absence of sepsis after ≥ 14 days of exposure to PN.

RESULTS

Median gestational age was 26 weeks and 68% were boys. Seventy percent of the cohort developed PNALD and the incidence of PNALD varied significantly across the 6 study sites, ranging from 56% to 85% (P = 0.05). Multivariable logistic regression analysis identified small-bowel resection or creation of jejunostomy (odds ratio [OR] 4.96, 95% confidence interval [CI] 1.97-12.51, P = 0.0007) and duration of PN in weeks (OR 2.37, 95% CI 1.56-3.60, P < 0.0001) as independent risk factors for PNALD. Preoperative exposure to PN was also associated with the development of PNALD; the risk of PNALD was 2.6 (95% CI 1.5-4.7; P = 0.001) times greater in patients with ≥ 4 weeks of preoperative PN compared with those with less preoperative PN use. Breast milk feedings, episodes of infection, and gestational age were not related to the development of PNALD.

CONCLUSIONS

The incidence of PNALD is high in infants with NEC undergoing surgical treatment. Risk factors for PNALD are related to signs of NEC severity, including the need for small-bowel resection or proximal jejunostomy, as well as longer exposure to PN. Identification of these and other risk factors can help in the design of clinical trials for the prevention and treatment of PNALD and for clinical assessment of patients with NEC and prolonged PN dependence.

Hepatobiliary manifestations of gastrointestinal and nutritional disorders

Hepatobiliary manifestations of gastrointestinal and nutritional disorders can occur as part of the clinical spectrum of the underlying disease or as a consequence of the treatment of the disease. This article reviews aspects of pathogenesis, diagnosis, and management of hepatobiliary manifestations associated with a selection of gastrointestinal and nutritional disorders including inflammatory bowel disease, celiac disease, Whipple's disease, and parenteral nutrition associated disorders.

Preventing parenteral nutrition liver disease

Parenteral nutrition liver disease (PNLD) develops in 40-60% of infants who require long-term PN for intestinal failure. The clinical spectrum includes hepatic steatosis, cholestasis, cholelithiasis, and hepatic fibrosis. Progression to biliary cirrhosis and the development of portal hypertension and liver failure occurs in a minority who require combined liver and intestinal transplantation. The pathogenesis is multifactorial and is related to prematurity, low birth weight, duration of PN, short bowel syndrome requiring multiple laparotomies and recurrent sepsis. Other important mechanisms include lack of enteral feeding which leads to reduced gut hormone secretion, reduction of bile flow and biliary stasis which leads to the development of cholestasis, biliary sludge and gallstones, which exacerbate hepatic dysfunction, especially in premature neonates with immature hepatic function. The use of lipid emulsions, particularly soy bean emulsions have been associated with hepatic cholestasis in children, although there are little data now to support toxicity from other PN components. Management strategies for the prevention of parenteral nutrition liver disease include consideration of early enteral feeding, a multidisciplinary approach to the management of parenteral nutrition with a specialized nutritional care team and aseptic catheter techniques to reduce sepsis. The use of specialized lipid emulsions such as fish oil emulsions and or SMOF (Soy bean/Medium Chain Triglyceride/Olive Oil/Fish oil) improves established cholestasis and may prevent the onset. Oral administration of ursodeoxycholic acid may improve bile flow and reduce gall bladder stasis, although there is little data to suggest that prophylactic use prevents the onset of PNLD. Survival following either isolated small bowel or combined liver and small bowel transplantation is approximately 50% at 5 years making this an acceptable therapeutic option in children with irreversible liver and intestinal failure.

Prevention of parenteral nutrition-associated liver disease: lipid minimization

PURPOSE OF REVIEW

The cause of parenteral nutrition-associated liver disease (PNALD) is unknown. Evidence over the past decade has suggested soybean oil-based intravenous emulsions are a contributing factor to the development of PNALD.

RECENT FINDINGS

This review details the historical and scientific rationale, which associates intravenous lipid emulsion administration and PNALD. The article then reviews our own group's experience with lipid restriction and the reversal of PNALD in neonates on long-term parenteral nutrition. Finally, a clinical approach to restricting soybean-based intravenous lipid emulsions in parenteral nutrition is given.

SUMMARY

An association between intravenous lipid emulsion administration and the development of PNALD seems probable. Strategies to reduce lipid emulsions or develop new, nonsoybean-based lipid emulsions should be considered.

Cholestasis in neonatal intensive care unit: incidence, aetiology and management

AIM

Prevalence, aetiology, management and outcome of cholestasis were evaluated in infants admitted to neonatal intensive care unit (NICU).

METHODS

Medical records of all infants admitted to two Italian level III NICUs from January 2005 to August 2007 were retrospectively reviewed. The role of ursodeoxycholic acid (UDCA) therapy was also investigated.

RESULTS

Twenty-seven of 1289 enrolled infants developed cholestasis. In 25 infants, cholestasis had a multifactorial basis, while in two, no aetiology was found. UDCA did not significantly affect clinical and biochemical course of cholestasis. During a period of 12 months, eight cholestatic infants died, one underwent liver transplantation and 18 fully recovered.

CONCLUSION

Infants admitted in NICU have a rate of cholestasis higher than that reported in the general population of live births; in most cases, cholestasis is associated to multiple risk factors and shows a favourable outcome. UDCA does not seem to affect clinical course of cholestasis in this setting.

Pediatric parenteral nutrition: putting the microscope on macronutrients and micronutrients

Parenteral nutrition can be a life-saving therapy, but its benefits need to be balanced with a unique set of risks and complications. Methods of practice vary because there is a dearth of research in the area of pediatric parenteral nutrition. This article reviews the available literature on parenteral nutrition in children and provides suggestions on prevention and management of parenteral nutrition-associated liver disease. Some of the issues discussed in this article include glucose infusion rates, cycling of parenteral nutrition, copper and manganese toxicity, and the provision of glutamine, selenium, and carnitine.

Parenteral nutrition-associated cholestasis in premature babies: risk factors and predictors

BACKGROUND

One of the most common complications in infants under parenteral nutrition treatment is parenteral nutrition-associated cholestasis (PNAC). The etiology of PNAC is thought to be multifactorial. The aims of this study were to evaluate the risk factors for PNAC in our neonatal intensive care unit and determine useful predictors.

METHODS

This study enrolled premature infants (gestational age <36 weeks) who were admitted to our neonatal intensive care unit and treated with parenteral nutrition infusion for at least 2 weeks between January 2004 and January 2007. Multiple possible risk factors were analyzed by a retrospective review study design. PNAC was defined as direct bilirubin greater than 1.5 mg/dL during parenteral nutrition.

RESULTS

A total of 62 premature infants with prolonged course of parenteral nutrition were eligible for this study; 11 (17.74%) of the infants developed PNAC. There were significant differences in terms of gestational age, birth body weight, duration of parenteral nutrition, septic episodes, and average energy intake during the 2nd and 3rd weeks of life between infants with cholestasis and those without cholestasis. Of these risk factors, the duration of parenteral nutrition was most significant after multivariate logistic regression analysis.

CONCLUSION

Young gestational age, low birth body weight, more sepsis episodes, and long duration of parenteral nutrition were significant risk factors for PNAC in our study. Low energy intake during the 2nd and 3rd weeks of life is a predictor for PNAC.

Alteration of canalicular transporters in a mouse model of total parenteral nutrition

OBJECTIVES

Parenteral nutrition-associated liver disease (PNALD) is a major problem with prolonged total parenteral nutrition (TPN) administration. Our laboratory previously demonstrated significant changes in the expression of multidrug resistance genes (MDRs) 1 and 2, hepatocyte transporters, in a TPN mouse model. The present study hypothesized that these changes would lead to functional changes in the liver, and would contribute to the development of liver dysfunction.

MATERIALS AND METHODS

Mice received either intravenous saline and standard chow or TPN with or without intravenous lipids. Functional assays were performed after 7 days of infusion.

RESULTS

TPN with lipids led to a significant increase in serum bile acid levels, consistent with an early state of PNALD. Use of TPN without lipids prevented an elevation in bile acid levels. In both TPN groups, MDR2 expression was significantly (68%) lower than controls and bile phosphatidylcholine content, a functional measure of MDR2, was 40% less than controls. MDR1 expression in the TPN with lipid group was 31% higher than controls, whereas in the TPN without lipids mice there was no significant change. Hepatocyte extrusion of rhodamine dye, a measure of MDR1 function, declined only in the TPN with lipid group. Peroxisome proliferator-activated receptor-alpha expression decreased in both TPN groups. Fenofibrate given with TPN resulted in an increased expression of MDR1 and MDR2, and functionally increased hepatocyte rhodamine extrusion and presence of bile phosphatidylcholine in the TPN with lipid group.

CONCLUSIONS

The study shows that TPN led to alterations in the function of MDR1- and MDR2-expressed proteins. The changes help in the understanding of the mechanisms leading to PNALD, and suggest that fibrate administration may palliate these changes.