Hepatic copper in patients receiving long-term total parenteral nutrition

Are Trace Elements Provided for Children on Long-Term Parenteral Nutrition Adequate to Meet Their Needs?

Background: We conducted a cross-sectional study to investigate whether children receiving long-term parenteral nutrition (LPN) are at risk of imbalances in selected trace elements. Methods: Serum levels of manganese, zinc, copper, selenium, and iodine were measured in 83 children on LPN and compared with 121 healthy controls. Children with signs of infection or elevated C-reactive protein levels were excluded. Elemental analysis was performed using inductively coupled plasma mass spectrometry (ICP-MS). Results: Manganese and copper levels were significantly lower in the study group compared with controls (p < 0.001) but remained within normal ranges. Iodine levels were also significantly lower in the study group (p < 0.05), though pediatric reference values are lacking. Zinc and selenium levels were significantly higher in the study group (p < 0.001), with median levels within normal ranges in both groups. Zinc, selenium, and iodine levels were higher in patients weighing ≤15 kg (p < 0.001, p < 0.001, p < 0.02). Conclusions: Serum concentrations of manganese, copper, and selenium in the study group remained within normal ranges, even though children weighing over 15 kg received doses below those recommended by scientific guidelines. An iodine intake below 1 μg/kg/day in patients weighing over 15 kg appears insufficient. Patients on LPN required a higher zinc intake than current recommendations.

ESPEN guideline on chronic intestinal failure in adults - Update 2023

BACKGROUND & AIMS

In 2016, ESPEN published the guideline for Chronic Intestinal Failure (CIF) in adults. An updated version of ESPEN guidelines on CIF due to benign disease in adults was devised in order to incorporate new evidence since the publication of the previous ESPEN guidelines.

METHODS

The grading system of the Scottish Intercollegiate Guidelines Network (SIGN) was used to grade the literature. Recommendations were graded according to the levels of evidence available as A (strong), B (conditional), 0 (weak) and Good practice points (GPP). The recommendations of the 2016 guideline (graded using the GRADE system) which were still valid, because no studies supporting an update were retrieved, were reworded and re-graded accordingly.

RESULTS

The recommendations of the 2016 guideline were reviewed, particularly focusing on definitions, and new chapters were included to devise recommendations on IF centers, chronic enterocutaneous fistulas, costs of IF, caring for CIF patients during pregnancy, transition of patients from pediatric to adult centers. The new guideline consist of 149 recommendations and 16 statements which were voted for consensus by ESPEN members, online in July 2022 and at conference during the annual Congress in September 2022. The Grade of recommendation is GPP for 96 (64.4%) of the recommendations, 0 for 29 (19.5%), B for 19 (12.7%), and A for only five (3.4%). The grade of consensus is "strong consensus" for 148 (99.3%) and "consensus" for one (0.7%) recommendation. The grade of consensus for the statements is "strong consensus" for 14 (87.5%) and "consensus" for two (12.5%).

CONCLUSIONS

It is confirmed that CIF management requires complex technologies, multidisciplinary and multiprofessional activity, and expertise to care for the underlying gastrointestinal disease and to provide HPN support. Most of the recommendations were graded as GPP, but almost all received a strong consensus.

Current Insights Regarding Intestinal Failure-Associated Liver Disease (IFALD): A Narrative Review

Intestinal failure-associated liver disease (IFALD) is a spectrum of liver disease including cholestasis, biliary cirrhosis, steatohepatitis, and gallbladder disease in patients with intestinal failure (IF). The prevalence of IFALD varies considerably, with ranges of 40-60% in the pediatric population, up to 85% in neonates, and between 15-40% in the adult population. IFALD has a complex and multifactorial etiology; the risk factors can be parenteral nutrition-related or patient-related. Because of this, the approach to managing IFALD is multidisciplinary and tailored to each patient based on the etiology. This review summarizes the current knowledge on the etiology and pathophysiology of IFALD and examines the latest evidence regarding preventative measures, diagnostic approaches, and treatment strategies for IFALD and its associated complications.

Intestinal Failure-Associated Liver Disease in Neonates

Intestinal failure-associated liver disease (IFALD) is common in neonates who suffer from intestinal failure and rely on parenteral nutrition. The etiology is multifactorial, relating to the infant's underlying cause of intestinal failure and other infant factors such as prematurity. Management of the disease includes transitioning to enteral feedings as soon as is safe for the infant. In infants who continue to rely on parenteral nutrition, alternative lipid emulsions and other medications may be used. This article reviews the epidemiology and factors that contribute to IFALD in neonates, in addition to management strategies.

Review of parenteral nutrition-associated liver disease

Parenteral nutrition has been widely used in patients whose gastrointestinal tract is anatomically or physiologically unavailable for sufficient food intake. It has been considered lifesaving but is not without adverse effects. It has been proven to cause liver injury through different mechanisms. We present a review of parenteral nutrition-associated liver disease.

Quantitative Assessment of Trace-Element Contamination in Parenteral Nutrition Components

BACKGROUND

Trace-element contamination of contemporary parenteral nutrition (PN) components exists in unknown quantities and, in combination with excessive amounts of certain trace elements provided in commercially available adult, pediatric, and neonatal multitrace-element (MTE) products, could result in eventual accumulation and toxicity. This study aims to quantify trace-element contamination in components used for PN compounding to further inform recommendations for MTE product reformulation and individualized trace-element prescribing in PN.

METHODS

A total of 32 unique components (65 products) available for PN compounding were tested for manganese, chromium, selenium, zinc, and copper contamination, utilizing inductively coupled plasma mass spectrometry. Theoretical adult, pediatric, and neonatal PNs were formulated to assess the impact of macronutrient and micronutrient component doses on PN trace-element contamination.

RESULTS

Trace-element contamination was detected in 24 (75%) components tested. Chromium and manganese were common, present in 65.6% and 51.5% of all components, respectively. Eight components did not contain detectable trace-element contamination, most notably sterile water, concentrated dextrose, and lipid emulsion. Manganese contamination in theoretical adult, pediatric, and neonatal PN was 25.18, 9.92, and 1.37 µg, respectively. Chromium contamination was 4.85, 1.5, and 0.28 µg, respectively.

CONCLUSION

Trace-element contamination was prevalent in components used to compound PN. Our findings support reformulation of adult, pediatric, and neonatal manufactured MTE products to eliminate chromium, decrease manganese, and supply full daily physiologic requirements of selenium, zinc, and copper. Future study is needed to assess the additional contamination that could occur through the compounding and storage processes.

Trace Element Provision in Parenteral Nutrition in Children: One Size Does Not Fit All

Routine administration of trace elements is recognised as a standard of care in children requiring parenteral nutrition. However, there is a lack of global consensus regarding trace elements provision and dosing in pediatric parenteral nutrition. This review provides an overview of available evidence regarding trace elements supply and posology in parenteral nutrition in neonates and children. Trace elements provision in children should be tailored to the weight and clinical condition of the child with emphasis on those at risk of toxicity or deficiency. Based on current evidence, there is a need to review the formulation of commercial solutions that contain multiple-trace elements and to enable individual trace elements additives to be available for specific indications. Literature supports the removal of chromium provision whereas manganese and molybdenum supplementation are debated. Preterm neonates may have higher parenteral requirements in iodine, selenium and copper than previously recommended. There is growing support for the routine provision of iron in long-term parenteral nutrition. Further studies on trace elements contamination of parenteral nutrition solutions are needed for a range of trace elements.

Parenteral Nutrition and Intestinal Failure

Severe short bowel syndrome (SBS) is a major cause of chronic (Type 3) intestinal failure (IF) where structural and functional changes contribute to malabsorption and risk of micronutrient deficiencies. Chronic IF may be reversible, depending on anatomy and intestinal adaptation, but most patients require long-term nutritional support, generally in the form of parenteral nutrition (PN). SBS management begins with dietary changes and pharmacologic therapies taking into account individual anatomy and physiology, but these are rarely sufficient to avoid PN. New hormonal therapies targeting intestinal adaptation hold promise. Surgical options for SBS including intestinal transplant are available, but have significant limitations. Home PN (HPN) is therefore the mainstay of treatment for severe SBS. HPN involves chronic administration of macronutrients, micronutrients, fluid, and electrolytes via central venous access in the patient's home. HPN requires careful clinical and biochemical monitoring. Main complications of HPN are related to venous access (infection, thrombosis) and metabolic complications including intestinal failure associated liver disease (IFALD). Although HPN significantly impacts quality of life, outcomes are generally good and survival is mostly determined by the underlying disease. As chronic intestinal failure is a rare disease, registries are a promising strategy for studying HPN patients to improve outcomes.

Trace Elements in Parenteral Nutrition: Considerations for the Prescribing Clinician

Trace elements (TEs) are an essential component of parenteral nutrition (PN). Over the last few decades, there has been increased experience with PN, and with this knowledge more information about the management of trace elements has become available. There is increasing awareness of the effects of deficiencies and toxicities of certain trace elements. Despite this heightened awareness, much is still unknown in terms of trace element monitoring, the accuracy of different assays, and current TE contamination of solutions. The supplementation of TEs is a complex and important part of the PN prescription. Understanding the role of different disease states and the need for reduced or increased doses is essential. Given the heterogeneity of the PN patients, supplementation should be individualized.

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.

Parenteral trace element provision: recent clinical research and practical conclusions

The aim of this systematic review (PubMed, www.ncbi.nlm.nih.gov/pubmed and Cochrane, www.cochrane.org; last entry 31 December 2014) was to present data from recent clinical studies investigating parenteral trace element provision in adult patients and to draw conclusions for clinical practice. Important physiological functions in human metabolism are known for nine trace elements: selenium, zinc, copper, manganese, chromium, iron, molybdenum, iodine and fluoride. Lack of, or an insufficient supply of, these trace elements in nutrition therapy over a prolonged period is associated with trace element deprivation, which may lead to a deterioration of existing clinical symptoms and/or the development of characteristic malnutrition syndromes. Therefore, all parenteral nutrition prescriptions should include a daily dose of trace elements. To avoid trace element deprivation or imbalances, physiological doses are recommended.

Management and Complications of Short Bowel Syndrome: an Updated Review

Short bowel syndrome (SBS) is defined as loss of bowel mass from surgical resection, congenital defects, or disease. Intestinal failure (IF) includes the subset of SBS unable to meet nutrition needs with enteral supplements and requires parenteral nutrition (PN). The parenteral treatment of SBS is now a half-century old. Recent pharmacologic treatment (GLP-2 analogues) has begun to make a significant impact in the care and ultimate management of these patients such that the possibility of reducing PN requirements in formerly PN-dependent patients is a now a real possibility. Finally, newer understanding and possible treatment for some of the complications related to IF have more recently evolved and will be an emphasis of this report. This review will focus on developments over the last 10 years with the goal of updating the reader to new advances in our understanding of the care and feeding of the SBS patient.

Antioxidant trace elements serum levels in long-term parenteral nutrition (PN): Prevalence and infectious risk associated with deficiencies, a retrospective study from a tertiary home-PN center

INTRODUCTION

Antioxidants essential trace elements (TEs), selenium (Se), zinc (Zn) and copper (Cu) are key dietary components and their supplementation in parenteral nutrition (PN) is recommended. However, the frequency of marginal deficiencies and related clinical outcomes remain poorly known in patients receiving long-term PN.

METHODS AND OBJECTIVES

We conducted a retrospective observational study whose aim was to determine in a cohort of patients (n = 73) with chronic intestinal failure (CIF) enrolled in a tertiary home PN center and receiving long-term PN with systematic multi-TE supplementation, the prevalence of low serum TEs levels. The goal was also to assess mid-term incidence of serious infection and its associated factors.

RESULTS

Among the 73 studied patients, 21.9%, 13.9% and 21.1% had low serum Se (<0.9 μmol/l), Cu (<12.7 μmol/l) and Zn (<12.5 μmol/l) levels, respectively. There was no difference between short bowel syndrome (SBS) and non-SBS patients. 30 patients had at least one of the three serum TEs levels under the cut-off values of deficiency. No specific disease and/or underlying intestinal anatomy were associated with low serum TEs concentration. Cumulative incidence rates of serious infection were 11.1% 95CI[5.7-21.0] and 19.5% 95CI[12.0-30.7] at 6 months and 1 year, respectively. Central venous catheter-related bloodstream infection was the most common infection. Low serum Se was independently associated with a higher risk to develop serious infection (HR 2.65 95CI[1.01-6.97]).

CONCLUSION

Low serum TEs concentration is a frequent condition in patients with CIF even with systematic multi-TE supplementations. Se deficiency exposes to a greater risk of serious infection. This suggests that frequent TEs dosage in this population as well as individually tailored supplementation may be beneficial.

ESPEN guidelines on chronic intestinal failure in adults

BACKGROUND & AIMS

Chronic Intestinal Failure (CIF) is the long-lasting reduction of gut function, below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, such that intravenous supplementation is required to maintain health and/or growth. CIF is the rarest organ failure. Home parenteral nutrition (HPN) is the primary treatment for CIF. No guidelines (GLs) have been developed that address the global management of CIF. These GLs have been devised to generate comprehensive recommendations for safe and effective management of adult patients with CIF.

METHODS

The GLs were developed by the Home Artificial Nutrition & Chronic Intestinal Failure Special Interest Group of ESPEN. The GRADE system was used for assigning strength of evidence. Recommendations were discussed, submitted to Delphi rounds, and accepted in an online survey of ESPEN members.

RESULTS

The following topics were addressed: management of HPN; parenteral nutrition formulation; intestinal rehabilitation, medical therapies, and non-transplant surgery, for short bowel syndrome, chronic intestinal pseudo-obstruction, and radiation enteritis; intestinal transplantation; prevention/treatment of CVC-related infection, CVC-related occlusion/thrombosis; intestinal failure-associated liver disease, gallbladder sludge and stones, renal failure and metabolic bone disease. Literature search provided 623 full papers. Only 12% were controlled studies or meta-analyses. A total of 112 recommendations are given: grade of evidence, very low for 51%, low for 39%, moderate for 8%, and high for 2%; strength of recommendation: strong for 63%, weak for 37%.

CONCLUSIONS

CIF management requires complex technologies, multidisciplinary and multiprofessional activity, and expertise to care for both the underlying gastrointestinal disease and to provide HPN support. The rarity of the condition impairs the development of RCTs. As a consequence, most of the recommendations have a low or very low grade of evidence. However, two-thirds of the recommendations are considered strong. Specialized management and organization underpin these recommendations.

Serial profile of vitamins and trace elements during the acute phase of allogeneic stem cell transplantation

Currently, we utilize vitamins and trace elements formulations that are not prepared specifically for patients receiving hematopoietic stem cell transplantation (HSCT), and adequacy of this strategy has not been evaluated. We prospectively measured blood level of vitamins and trace elements in 15 patients once per week at 6 time points around the acute phase of allogeneic HSCT. We provided standard nutrition support, including administration of parenteral nutrition with vitamin and trace elements formulation in case of impairment of oral intake. Most patients had vitamin B1 deficiency from the start of preparative regimens. Vitamin C deficiency was prominent throughout the acute phase of HSCT and this was significantly associated with high inflammatory markers, C-reactive protein and ferritin. Remarkable vitamin K overload associated with administration of parenteral supplementation and ferritin overload caused by repeated transfusions was observed. Moderate deficiency of zinc was at least partially linked to gastrointestinal loss by diarrhea. We revealed several features of vitamin and trace element status in the acute phase of HSCT and provided a basis for attempts to improve the nutritional condition in HSCT recipients.

Parenteral trace elements in children: clinical aspects and dosage recommendations

PURPOSE OF REVIEW

Since the 1970s, it has been known that the supplementation of trace elements with parenteral nutrition is required in order to avoid the clinical manifestations of their deficiencies. However, the correct level of requirements of these trace elements, particularly in paediatrics, has provided some debate. The recent developments might help revise some of the current recommendations, particularly in short-term parenteral nutrition provision.

RECENT FINDINGS

Parenterally fed preterm neonates require routine addition of zinc. Provision of chromium and manganese in parenteral nutrition should be limited, particularly for short-term patients. Newer parenteral iron preparations provide the opportunity for a safer and larger dose of administration.

SUMMARY

Clinicians should prescribe according to the individual requirements and revise the routine practice of providing 'all in one' parenteral trace elements preparations, as these products do not reflect or allow tailored provision in paediatrics and may increase the risk of toxicity.

A.S.P.E.N. position paper: recommendations for changes in commercially available parenteral multivitamin and multi-trace element products

The parenteral multivitamin preparations that are commercially available in the United States (U.S.) meet the requirements for most patients who receive parenteral nutrition (PN). However, a separate parenteral vitamin D preparation (cholecalciferol or ergocalciferol) should be made available for treatment of patients with vitamin D deficiency unresponsive to oral vitamin D supplementation. Carnitine is commercially available and should be routinely added to neonatal PN formulations. Choline should also be routinely added to adult and pediatric PN formulations; however, a commercially available parenteral product needs to be developed. The parenteral multi-trace element (TE) preparations that are commercially available in the U.S. require significant modifications. Single-entity trace element products can be used to meet individual patient needs when the multiple-element products are inappropriate (see Summary/A.S.P.E.N. Recommendations section for details of these proposed modifications).

Role of trace elements in parenteral nutrition support of the surgical neonate

BACKGROUND

Parenteral nutrition (PN) has transformed the outcome for neonates with surgical problems in the intensive care unit. Trace element supplementation in PN is a standard practice in many neonatal intensive care units. However, many of these elements are contaminants in PN solutions, and contamination levels may, in themselves, be sufficient for normal metabolic needs. Additional supplementation may actually lead to toxicity in neonates whose requirements are small.

METHODS

An electronic search of the MEDLINE, Cochrane Collaboration, and SCOPUS English language medical databases was performed for the key words "trace elements," "micro-nutrients," and "parenteral nutrition additives." Studies were categorized based on levels of evidence offered, with randomized controlled trials and meta-analyses accorded the greatest importance at the apex of the data pool and case reports and animal experiments the least importance. Articles were reviewed with the primary goal of developing uniform recommendations for trace element supplementation in the surgical neonate. The secondary goals were to review the physiologic role, metabolic demands, requirements, losses, deficiency syndromes, and toxicity symptoms associated with zinc, copper, chromium, selenium, manganese, and molybdenum supplementation in PN.

RESULTS

Zinc supplementation must begin at initiation of PN. All other trace elements can be added to PN 2 to 4 weeks after initiation. Copper and manganese need to be withheld if the neonate develops PN-associated liver disease. The status of chromium supplementation is currently being actively debated, with contaminant levels in PN being sufficient in most cases to meet neonatal requirements. Selenium is an important component of antioxidant enzymes with a role in the pathogenesis of neonatal surgical conditions such as necrotizing enterocolitis and bronchopulmonary dysplasia. Premature infants are often selenium deficient, and early supplementation has shown a reduction in sepsis events in this age group.

CONCLUSION

Appropriate supplementation of trace elements in surgical infants is important, and levels should be monitored. In certain settings, it may be more appropriate to individualize trace element supplementation based on the predetermined physiologic need rather than using bundled packages of trace elements as is the current norm. Balance studies of trace element requirements should be performed to better establish clinical recommendations for optimal trace element dosing in the neonatal surgical population.

Parenteral nutrition-associated cholestasis: an American Pediatric Surgical Association Outcomes and Clinical Trials Committee systematic review

OBJECTIVE

The aim of this study was to review evidence-based data addressing key clinical questions regarding parenteral nutrition-associated cholestasis (PNAC) and parenteral nutrition-associated liver disease (PNALD) in children.

DATA SOURCE

Data were obtained from PubMed, Medicine databases of the English literature (up to October 2010), and the Cochrane Database of Systematic Reviews.

STUDY SELECTION

The review of PNAC/PNALD has been divided into 4 areas to simplify one's understanding of the current knowledge regarding the pathogenesis and treatment of this disease: (1) nonnutrient risk factors associated with PNAC, (2) PNAC and lipid emulsions, (3) nutritional (nonlipid) considerations in the prevention of PNAC, and (4) supplemental medications in the prevention and treatment of PNAC.

RESULTS

The data for each topic area relevant to the clinical practice of pediatric surgery were reviewed, evaluated, graded, and summarized.

CONCLUSIONS

Although the conditions of PNAC and PNALD have been well recognized for more than 30 years, only a few concrete associations and treatment protocols have been established.

Copper metabolism and pediatric cholestasis

PURPOSE OF REVIEW

Copper is an essential trace mineral but both deficiency and toxicity need to be avoided. Copper is regulated via excretion by the biliary system and caution was recommended when administered in patients with cholestasis. Recent clinical reports indicate that despite the cholestasis, copper should not be withheld from parenteral nutrition.

RECENT FINDINGS

Transporters involved in regulating copper levels have been identified. This explains the processes that regulate copper levels and the diseases that result from transporter defects. Monitoring copper ideally requires a liver biopsy but there are reports that in infants serum copper levels correlate with the liver copper. The published cautions about copper in cholestatic patients on parenteral nutrition led to the removal of copper from the solutions. Subsequently, multiple reports of clinical copper deficiency developing in these patients including infants were published. Newer literature indicates no elevation in infant copper levels despite normal copper parenteral nutrition supplementation in the presence of cholestasis.

SUMMARY

Copper is essential and levels are regulated in response to an individual's needs. The liver excretion of copper is the primary regulating method but clinically cholestasis does not result in elevated levels in infants. The best clinical approach to parenteral nutrition copper is careful monitoring even in the presence of cholestasis.

Clinical parameters and biomarkers of oxidative stress in agricultural workers who applied copper-based pesticides

Copper based-pesticides are widely used in agricultural practice throughout the world. We studied the (i) concentration of Cu and proteins involved in Cu homeostasis, (ii) plasma redox status, and (iii) biomarkers of exposure in Cu-based pesticide applicators in order to compare them with clinical biochemical tests. Thirty-one professional applicators and 32 control subjects were recruited. Oxidative stress biomarkers, ceruloplasmin (CRP), metallothioneins (MTs), copper, hematological parameters, and biochemical markers for pancreatic, hepatic and renal function were measured in plasma. Copper was increased in the exposed group compared to the control group concomitantly with TBARS, protein carbonyls, and nitrate+nitrite levels. In the exposed group, α-tocopherol and the FRAP assay were lower and LDH, transaminases, GGT, ALP, urea, creatinine, CRP and MTs were higher than in the control group. The relative leukocyte subclasses were also different between the two groups. Clinical chemistry tests did not surpass the upper reference limit. Our results suggest that the incorporation of oxidative stress biomarkers to biochemical/clinical tests should be considered for validation and included in the human health surveillance protocols.

Dosing and monitoring of trace elements in long-term home parenteral nutrition patients

BACKGROUND

Trace elements (TEs) dosing and monitoring in home parenteral nutrition (PN) patients vary with their underlying conditions.

METHODS

This retrospective observational study evaluated parenteral TE dosing, serum TE concentrations and monitoring, and dose-concentration relationships between TE doses and serum TE concentrations in 26 adult and adolescent home PN patients.

RESULTS

There was a total of 40,493 PN days. Average parenteral zinc doses of 9.1 mg/d and 7.6 mg/d resulted in the majority of serum zinc concentrations (90%) within normal range in patients with and without short bowel syndrome (SBS), respectively. Selenium at about 70 mcg/d resulted in about 60% of serum selenium concentrations within normal range, with 38% of values below normal in patients with and without SBS alike. Copper at 1 mg/d resulted in 22.5% of serum copper concentrations above the normal range. The majority of serum manganese (94.6%) and chromium (96%) concentrations were elevated. Serum TE concentrations were infrequently monitored. Significant relationships existed between doses and serum concentrations for zinc (P < .0001), manganese (P = .012), and chromium (P < .0001) but not for selenium or copper.

CONCLUSIONS

TE doses in home PN should be individualized and adjusted based on regular monitoring of TE status. In long-term home PN patients, higher zinc and selenium doses may be necessary to maintain their normal serum concentrations. Lower copper doses and restrictions of manganese and chromium supplementation may be needed to avoid their accumulation. Relationships between TE doses and serum TE concentrations vary for each TE and underlying clinical conditions.

Abnormal liver function tests in the parenteral nutrition fed patient

Liver dysfunction is common in individuals receiving parenteral nutrition (PN) and particularly in neonates and infants. Abnormalities of liver function tests in patients receiving short term PN are usually transient but in individuals receiving long term PN, substantial liver damage and ultimately end stage liver disease may occur. The aetiology is complex, involving a large number of patient related and nutrition related factors. The terminology intestinal failure associated liver disease (IFALD) is therefore more appropriate than PN associated liver disease. Effort should be made to prevent liver dysfunction by managing sepsis, avoiding parenteral overfeeding, employing cyclical parenteral feeding and encouraging enteral nutrition where possible. Intake of soybean based parenteral lipid emulsions should be reduced in individuals with established IFALD, possibly to be replaced by lipid emulsions containing medium chain triacylglycerol, monounsaturated fatty acids or fish oil although larger clinical studies are needed. Similarly, evidence supporting the widespread use of parenteral choline and taurine supplementation in the prevention or treatment of IFALD remains limited. There are more data to support the use of oral antibiotics to treat bacterial overgrowth and oral ursodeoxycholic acid in neonates. Ultimately, severe IFALD may necessitate referral for small intestine and/or liver transplantation.

Copper supplementation in parenteral nutrition of cholestatic infants

BACKGROUND AND OBJECTIVES

Conventional practice is to reduce or eliminate copper (Cu) supplementation in the parenteral nutrition of infants with cholestasis because of the increased risk of hepatotoxicity. However, there are reports of Cu deficiency in cholestatic infants because of Cu reduction in their parenteral nutrition. The objectives of the present study are to determine the proportion of cholestatic infants who develop elevated serum Cu while receiving a nonreduced dose of parenteral Cu, to evaluate potential clinical factors that affect serum Cu in cholestatic infants, and to evaluate the impact of serum Cu on liver disease.

PATIENTS AND METHODS

This is a retrospective review of 28 cholestatic infants receiving 20 microg x kg(-1) x day(-1) of Cu via parenteral nutrition. Age-adjusted references were used to determine normality of serum Cu levels. Multiple linear regression analyses were performed to determine predictors of serum Cu and alanine aminotransferase (ALT).

RESULTS

Serum Cu levels were elevated in 2 infants (7%). On average, infants received 80% of their energy intake from parenteral nutrition for 3 months. Intestinal failure was present in 50% of the patients. Birth weight, gestational age, and ALT were identified as predictors of serum Cu (R2 = 0.53; P = 0.0001). Serum Cu, gestational age, and total bilirubin were associated with serum ALT (R2 = 0.43; P = 0.001).

CONCLUSIONS

Supplementation of parenteral Cu at 20 microg x kg(-1) x day(-1) does not lead to a significant increase in Cu toxicity or worsening of liver disease in cholestatic infants.

Short Bowel Syndrome

This review deals with the complications and treatment of short bowel syndrome (SBS), addressing the psychosocial, medical, and surgical complications in children receiving long-term parenteral nutrition (PN) support, as well as factors that affect the intestinal adaptation process. Whenever possible, as much of the colon as possible is retained in continuity because the colon is an avid absorber of sodium. It is also important for clinicians to be aware of the important absorption mechanisms in the different regions of the bowel. For example, resection of the terminal ileum removes vitamin B12 transporters and active sodium-coupled bile salt transporters. Treatment of patients missing the terminal ileum may require monthly vitamin B12 injections and oral bile salt binders, such as cholestyramine, when the colon is present to reduce the volume of diarrhea. Patients who do not have ileocecal valves (ICVs) are prone to small bowel bacterial overgrowth that requires treatment to facilitate the intestinal adaptation process. We discuss how the PN is decreased as enteral feedings are advanced as well as clinical monitoring and routine laboratory tests. Although much has been learned over the past 20 years about PN, major questions remain, including determining the optimal form of intravenous lipid (omega-3 preparations versus omega-6 lipids versus a combination of both) to prevent liver disease.

Managing liver dysfunction in parenteral nutrition

Parenteral nutrition is life saving in patients with intestinal failure but liver dysfunction is commonly encountered, especially in neonates. Although abnormal liver function tests associated with short-term parenteral nutrition are usually benign and transient, liver dysfunction in both children and adults receiving long-term parenteral nutrition can progress to end-stage liver disease and liver failure. The aetiology of parenteral nutrition-associated liver disease is complex and multifactorial, with a range of patient, disease and nutrition-related factors implicated. Sepsis is of particular importance, as is the lack of enteral nutrition and overfeeding with intravenous glucose and/or lipid. Deficiencies of a number of amino acids including choline and taurine have also been implicated. Management of hepatic dysfunction in parenteral nutrition should initially focus on preventing its occurrence. Sepsis should be managed appropriately, enteral nutrition should be encouraged and maximised where possible and parenteral overfeeding should be avoided. Provision of parenteral lipid should be optimised to prevent the adverse effects of both deficiency and excess, and cyclical rather than continuous parenteral feeding should be administered. There is some evidence of benefit in neonates from oral antibiotics to prevent intestinal bacterial overgrowth and from oral ursodeoxycholic acid, but less to support their use in adults. Similarly, data to support widespread use of parenteral choline or taurine supplementation are lacking at present. Ultimately, severe parenteral nutrition-associated liver disease may necessitate referral for small intestine and/or liver transplantation.

Identifying patients, on the first day of life, at high-risk of developing parenteral nutrition-associated liver disease

BACKGROUND

Prolonged use of parenteral nutrition (PN) in neonates can lead to parenteral nutrition-associated liver disease (PNALD), manifested by elevated direct bilirubin concentrations, and in some cases progressing to hepatic failure. When new potential means of preventing PNALD in the neonatal intensive care unit (NICU), such as Omegaven usage, are tested in clinical trials, the studies should enroll neonates at a very high risk of developing PNALD. However, it is not always clear, in the first days of life, which neonates are most likely to develop PNALD. Therefore, preparatory to devising studies of prophylaxis against PNALD, we conducted an evaluation of all NICU patients who received PN for >or=14 day, assessing their likelihood of developing PNALD.

METHODS

We performed an historic cohort analysis of all neonates in the Intermountain Healthcare system, receiving PN for 14 days or more during their stay, with dates of birth between 1 January, 2002 and 30 June, 2006.

RESULTS

During the 4(1/2)-year period, 9861 neonates were cared for in the Intermountain Healthcare NICUs. Of these, 9547 (96.8%) survived for at least 28 days, and of these 6543 (68.5%) received PN. Twenty-one percent (1366 patients) of those receiving PN, received it for >or=14 days. PNALD was ascertained in this group by a direct bilirubin >or=2.0 mg/dl. Neonates receiving PN for 14-28 days had a 14% incidence of PNALD, those receiving PN for 29-56 days had a 43% incidence, those receiving PN for 57-100 days had a 72% incidence and those receiving PN for >100 days had a 85% incidence. Groups of patients identifiable on the first day of life as having the highest risk of developing PNALD were birth weight <500 g (odds ratio (OR), 30.7), birth weight 500-749 g (OR, 13.1), gastrochisis (OR, 20.3) and jejunal atresia (OR, 24.0). Among 357 patients who developed PNALD, the highest direct bilirubin concentrations correlated with the highest serum alkaline phosphatase and transaminase concentrations. Deaths after 28 days were much more common in those with the highest direct bilirubin and transaminase concentrations (P<0.0001).

CONCLUSIONS

In the first days of life, certain NICU patients can be identified as being at very high risk for developing PNALD. These are patients <750 g birth weight, those with gastrochisis and those with jejunal atresia. We speculate that these groups would be reasonable subjects for including in a PNALD prophylaxis trial, testing new preventative strategies such as Omegaven usage.

Nutritional management of infants with short bowel syndrome

The prevalence of short bowel syndrome appears to be increasing because of more aggressive surgical and medical approaches to the management of neonatal intraabdominal catastrophies. Hence, a large cohort of neonates with intestinal failure occupies neonatal intensive care units, requiring chronic total parenteral nutrition (TPN) in hopes that the residual bowel will adapt, thereby permitting weaning of TPN. Alternatively, when there is no hope for adaptation, these infants are maintained on TPN in hopes that they will grow to a size and state of general health satisfactory for either isolated intestinal transplant when liver function is preserved or combined liver-intestinal transplantation when the liver is irreparably damaged. Thus, it is imperative to provide enough parenteral nutrition to facilitate growth while minimizing TPN constituents predisposing to liver damage. Liver disease associated with intestinal failure (IFALD) seems to occur due to a variety of host factors combined with deleterious components of TPN. Host factors include an immature bile secretory mechanism, bile stasis due to fasting, and repeated septic episodes resulting in endotoxemia. Many constituents of TPN are associated with liver damage. Excessive glucose may result in fatty liver and/or hepatic fibrosis, excessive protein may lead to reduced bile flow, and phytosterols present in intravenous lipid may produce direct oxidant damage to the liver or may impede cholesterol synthesis and subsequent bile acid synthesis. Parenteral strategies employed to minimize TPN damage include reducing glucose infusion rates, reducing parenteral protein load, and reducing parenteral lipid load. Furthermore, preliminary studies suggest that fish oil-based lipid solutions may have a salutary effect on IFALD. Ultimately, provision of enteral nutrition is imperative for preventing or reversing IFALD as well as facilitating bowel adaptation. While studies of trophic hormones are ongoing, the most reliable current method to facilitate adaptation is to provide enteral nutrition. Continuous enteral feeding remains the mainstay of enteral nutrition support.

Parenteral nutrition

PURPOSE OF REVIEW

During the past 12 months there have been clinically important advances in intravenous nutrition and adjunctive therapies.

RECENT FINDINGS

Useful steps have been taken in the understanding of the altered physiology of the intravenously fed patient, the potential for specific gains from manipulation with gut hormones, and avoidance of complications from amended lipid emulsions. The role of the nutrition team and the place of IVN in malignancy have also been addressed.

SUMMARY

Glucagon-like peptide-2, and lipid emulsions based less on soy-bean oil appear safe and effective. Euglycaemia is recommended at all times, but not too much vitamin C. Long-term intravenous nutrition in cancer patients can be justified, and hospital nutrition teams are probably cost-effective.

Parenteral nutrition-associated liver disease and the role for isolated intestine and intestine/liver transplantation

Parenteral nutrition-associated liver disease (PNALD) is the most devastating complication of long-term parenteral nutrition therapy. Because its progression is typically insidious and its long-term consequences are generally underappreciated, PNALD is often recognized too late, when liver injury is irreversible. When end-stage liver disease (ESLD) develops in these patients, most potential interventions are futile and transplantation of both an intestine and a liver becomes the only viable option, despite the relatively poor outcomes associated with this combined procedure. Although likely multifactorial in origin, the etiology of PNALD is poorly understood. Early clinical intervention with a combination of nutritional, medical, hormonal, and surgical therapies can be effective in preventing liver disease progression. If these interventions fail, intestinal transplantation should be performed expeditiously before development of ESLD mandates simultaneous inclusion of a liver graft as well.