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

Total Parenteral Nutrition-Induced Cholestasis: Prevention and Management

When cholestasis occurs in patients receiving total parenteral nutrition, it is the result of many pathogenic pathways converging on the hepatic acinus. The result may be a temporary rise in liver function tests. The resulting fibrosis, portal hypertension, and jaundice are hallmarks of type 3 intestinal-associated liver disease to which children are more susceptible than adults. The key to prevention is in identifying high-risk scenarios, meticulous monitoring, and personalized prescription of parenteral nutrition solutions combined with an active approach in reducing the impact of inflammatory events when they occur by prompt use of antibiotics and line locks.

Parenteral nutrition-associated liver disease in extremely low-birthweight infants with intestinal disease

BACKGROUND

The aim of this study was to investigate factors associated with the development of parenteral nutrition-associated liver disease (PNALD) and to examine the clinicopathological relationship of PNALD in extremely low-birthweight infants (ELBWI).

METHODS

The subjects were 13 ELBWI who had received PN because of intestinal perforation or functional ileus between 2000 and 2013. We measured the serum levels of biochemical parameters, including aspartate aminotransferase, alanine aminotransferase, and direct bilirubin. Liver histopathology was examined in relation to outcome. The subjects were categorized into two groups on liver histopathology: F(+), development of hepatic fibrosis and necrosis with/without cholestasis; and F(-), no hepatic fibrosis.

RESULTS

Of 13 ELBWI, five died of hepatic failure, five died of sepsis, and the other three were alive at the time of the study. Of the five infants who died of hepatic failure, two developed fulminant hepatitis without cholestasis, and the other three developed chronic cholestasis and finally hepatic failure. Postmortem histopathology in F(+) indicated not only massive hepatic necrosis, but also massive hepatic fibrosis. These histopathological findings explained the clinical presentation of portal hypertension. There were significant differences in the fasting period after intestinal disease onset between the two groups.

CONCLUSION

The prolonged fasting with PN is responsible for severe hepatocellular necrosis with fibrosis and consequent lethal portal hypertension.

Gastrointestinal Manifestations, Malnutrition, and Role of Enteral and Parenteral Nutrition in Patients With Scleroderma

Scleroderma (systemic sclerosis) is an autoimmune disease that can affect multiple organ systems. Gastrointestinal (GI) involvement is the most common organ system involved in scleroderma. Complications of GI involvement including gastroesophageal reflux disease, small intestinal bacterial overgrowth, and chronic intestinal pseudoobstruction secondary to extensive fibrosis may lead to nutritional deficiencies in these patients. Here, we discuss pathophysiology, progression of GI manifestations, and malnutrition secondary to scleroderma, and the use of enteral and parenteral nutrition to reverse severe nutritional deficiencies. Increased mortality in patients with concurrent malnutrition in systemic sclerosis, as well as the refractory nature of this malnutrition to pharmacologic therapies compels clinicians to provide novel and more invasive interventions in reversing these nutritional deficiencies. Enteral and parenteral nutrition have important implications for patients who are severely malnourished or have compromised GI function as they are relatively safe and have substantial retrospective evidence of success. Increased awareness of these therapeutic options is important when treating scleroderma-associated malnutrition.

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

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

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.

Glutamine-supplemented parenteral nutrition and probiotics in four adult autoimmune enteropathy patients

To evaluate the effects of glutamine-supplemented parenteral nutrition (PN) and probiotics in adult autoimmune enteropathy (AIE) patients. Four adult AIE patients were identified from April 2006 to January 2012. Clinical and nutritional data were obtained from the patients' medical records. Glutamine-supplemented PN started immediately when the AIE diagnosis was confirmed. The total PN duration was 351 days. According to the PN prescription, the average caloric intake ranged from 20 to 25 kcal/kg/day, and the protein intake ranged from 1.2 to 1.5 g/kg/day. Alanyl-glutamine (20 g/day) was administered to AIE patients for 4 weeks followed by a 2-week break, and this treatment schedule was repeated when PN lasted for more than 6 weeks. Body weight gain and an increased serum albumin level were achieved after PN, and defecation frequency and quality also improved. Each patient received oral supplements, 250 mL of Ensure and two probiotics capsules (each capsule containing 0.5×108 colonies) three times a day when enteral nutrition started. Three AIE patients were successfully weaned off PN, and one patient died of pneumonia. Glutamine-supplemented PN and probiotics show promise in managing patients with AIE and related malnutrition.

Phase IV prospective clinical study to evaluate the effect of taurine on liver function in postsurgical adult patients requiring parenteral nutrition

BACKGROUND

Taurine's role in bile acid metabolism and anti-inflammatory activity could exert a protective effect on hepatobiliary complications associated with parenteral nutrition (PN). In this study, the effects of 2 amino acid solutions, with and without taurine, on liver function administered to nonacutely ill postsurgical patients as part of a short-term PN regimen were prospectively compared.

METHODS

Adult patients randomly received (double-blind) Tauramin 10% or a standard PN solution without taurine as the control (1.5 g amino acid/kg body weight [bw]/d; infusion rate of ≤4 mg glucose/kg bw/d) for a period of 5-30 days. γ-Glutamyl transpeptidase (GGT) and other indicators of liver function, glucose metabolism, lipid profile, inflammation markers, and treatment safety data were collected.

RESULTS

Thirty-five patients receiving taurine PN and 39 receiving control PN were enrolled (intention-to-treat [ITT] population). Most patients (n = 62) discontinued after day 7 of follow-up (per-protocol [PP] population: n = 24 and n = 27, respectively). ITT patients with high GGT values after 5 days of PN comprised 68.6% and 64.1%, respectively. The mean change in GGT values with respect to the baseline values was 167 ± 192 and 157 ± 185 IU/L, respectively. Low-density lipoprotein (LDL) cholesterol levels after 7 days of PN were significantly decreased in the taurine PN group of PP patients (-2.83 ± 30.9 vs 23.9 ± 27.0 mg/dL for control PN; P < .05). None of the adverse events reported (taurine PN: n = 6; control PN: n = 7) were treatment related.

CONCLUSION

PN solutions with and without taurine had similar effects on liver function parameters, except for an LDL reduction in PN with taurine, when administered to nonacutely ill postsurgical patients in the short term (5-7 days).

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-induced cholestasis in neonates: where does the problem lie?

Background. Parenteral nutrition (PN) is an effective method of nourishing the neonate who is unable to receive full enteral feeds. Cholestasis can be a complication of PN and can lead to severe liver damage. Aim. We describe our patient population and determine risk factors for developing PN cholestasis. Methods. Retrospective chart review of newborns admitted from January 2006 to May 2011 to the Neonatal Intensive Care Unit at our institution and received PN >14 days. Cholestasis was defined as serum conjugated bilirubin >50  μ mol/L. Results. Eighty-seven newborns were included; 18 (20.7%) developed PN cholestasis. The most frequent surgical condition for both groups was gastroschisis (8/87; 9.2%). No significant differences were found between the cholestasis and control groups for the following parameters: birth weight, gestational age, intrauterine growth restriction, Apgar scores, and day of life at initiation of enteral feeds. Duration of PN in days and dosage of carbohydrates in g/kg/day were significantly higher in the cholestasis group than the control group. Conclusion. PN-related cholestasis presented in one-fifth of neonates receiving PN for more than two weeks. Longer duration of PN and higher dosage of carbohydrates were independent risk factors for the development of PN cholestasis in this population.

Four-week parenteral nutrition using a third generation lipid emulsion (SMOFlipid)--a double-blind, randomised, multicentre study in adults

PRECIS

The aim of this study was to evaluate the safety and tolerance of a soybean/MCT/olive/fish oil emulsion in intestinal failure patients on long-term parenteral nutrition. 73 patients took part in a randomized, double-blind, multi-centre study. The study demonstrates that the lipid emulsion containing four different types of oils is safe and well tolerated in long-term PN.

BACKGROUND & AIM

Long-term safety and efficacy of a lipid emulsion containing soybean oil, medium-chain triglycerides (MCT), olive oil and fish oil and enriched in vitamin E have not yet been evaluated in adult patients requiring long-term parenteral nutrition (PN).

METHODS

Randomised, controlled, double-blind, multicentre study in 73 patients with stable intestinal failure, requiring PN with either soybean/MCT/olive/fish emulsion (SMOFlipid, n = 34) or soybean emulsion (Intralipid, control n = 39) for 4 weeks. Safety and tolerance were monitored with standard clinical laboratory parameters, adverse events (AEs, according to the Common Terminology Criteria for Adverse Events (CTCAE) classification v 3.0) and vital signs. Fatty acid pattern in red blood cell phospholipids and plasma lipoproteins, serum Vitamin E, Interleukin (IL)-6, and soluble tumour necrosis (s-TNF)-receptor(R)II were also evaluated.

RESULTS

Mean concentrations of alanine transaminase (ALT), aspartate transaminase (AST) and total bilirubin, whilst remaining within the reference range, were significantly lower with soybean/MCT/olive/fish (SMOF) oil emulsion after the treatment period compared to control. Eicosapentaenoic acid, docosahexaenoic acid and n-3/n-6 fatty acid ratio increased in the SMOF group, while they remained unchanged in the control in plasma and RBC. Serum α-tocopherol concentrations significantly increased in the study group compared to control (p = 0.0004). IL-6 and sTNF-RII levels did not change during the study period. Grade 4 (serious) adverse events occurred in 2 SMOF patients and in 8 control patients (p = 0.03).

CONCLUSIONS

Soybean/MCT/olive/fish emulsion was safe and well tolerated over 4 weeks and leads to positive change in fatty acids profile.

How aluminum, an intracellular ROS generator promotes hepatic and neurological diseases: the metabolic tale

Metal pollutants are a global health risk due to their ability to contribute to a variety of diseases. Aluminum (Al), a ubiquitous environmental contaminant is implicated in anemia, osteomalacia, hepatic disorder, and neurological disorder. In this review, we outline how this intracellular generator of reactive oxygen species (ROS) triggers a metabolic shift towards lipogenesis in astrocytes and hepatocytes. This Al-evoked phenomenon is coupled to diminished mitochondrial activity, anerobiosis, and the channeling of α-ketoacids towards anti-oxidant defense. The resulting metabolic reconfiguration leads to fat accumulation and a reduction in ATP synthesis, characteristics that are common to numerous medical disorders. Hence, the ability of Al toxicity to create an oxidative environment promotes dysfunctional metabolic processes in astrocytes and hepatocytes. These molecular events triggered by Al-induced ROS production are the potential mediators of brain and liver disorders.

Pathogenesis and treatment of parenteral nutrition-associated liver disease

BACKGROUND

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

DATA SOURCES

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

RESULTS

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

CONCLUSIONS

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

Outcome on home parenteral nutrition for benign intestinal failure: a review of the literature and benchmarking with the European prospective survey of ESPEN

BACKGROUND & AIMS

Indications and timing for referral for intestinal transplantation (ITx) were investigated through a review of the literature on home parenteral nutrition (HPN) for benign intestinal failure and a benchmarking to the results of a prospective European survey which evaluated the appropriateness of the current indications for ITx.

METHODS

Manuscripts reporting outcomes of adults and children on HPN were retrieved through a PubMed search. Data from the European survey were compared with those on HPN reported in the literature, and with those on ITx reported by the USA registry and by the Pittsburgh center.

RESULTS

HPN is a safe treatment with a high probability of survival. The risk of death during HPN is increased by the absence of a specialist team, and appears greater during the early period of treatment. Survival probability is decreased in patients with: age >40 or <2 years, very short bowel remnant, presence of a stoma, chronic intestinal pseudo-obstruction of myopathic origin, systemic sclerosis, radiation enteritis, intra-abdominal desmoids, necrotizing enterocolitis, congenital mucosal diseases. Liver failure is the HPN-related complication with the greatest risk of death. Death related to venous catheter complications is rare. The benchmarking supported the results of the European survey.

Toll-like receptor 4-dependent Kupffer cell activation and liver injury in a novel mouse model of parenteral nutrition and intestinal injury

Infants with intestinal failure who are parenteral nutrition (PN)-dependent may develop cholestatic liver injury and cirrhosis (PN-associated liver injury: PNALI). The pathogenesis of PNALI remains incompletely understood. We hypothesized that intestinal injury with increased intestinal permeability combined with administration of PN promotes lipopolysaccharide (LPS)-Toll-like receptor 4 (TLR4) signaling dependent Kupffer cell (KC) activation as an early event in the pathogenesis of PNALI. We developed a mouse model in which intestinal injury and increased permeability were induced by oral treatment for 4 days with dextran sulphate sodium (DSS) followed by continuous infusion of soy lipid-based PN solution through a central venous catheter for 7 (PN7d/DSS) and 28 (PN28d/DSS) days. Purified KCs were probed for transcription of proinflammatory cytokines. PN7d/DSS mice showed increased intestinal permeability and elevated portal vein LPS levels, evidence of hepatocyte injury and cholestasis (serum aspartate aminotransferase, alanine aminotransferase, bile acids, total bilirubin), and increased KC expression of interleukin-6 (Il6), tumor necrosis factor α (Tnfα), and transforming growth factor β (Tgfβ). Markers of liver injury remained elevated in PN28d/DSS mice associated with lobular inflammation, hepatocyte apoptosis, peliosis, and KC hypertrophy and hyperplasia. PN infusion without DSS pretreatment or DSS pretreatment alone did not result in liver injury or KC activation, even though portal vein LPS levels were elevated. Suppression of the intestinal microbiota with broad spectrum antibiotics or ablation of TLR4 signaling in Tlr4 mutant mice resulted in significantly reduced KC activation and markedly attenuated liver injury in PN7d/DSS mice.

CONCLUSION

These data suggest that intestinal-derived LPS activates KC through TLR4 signaling in early stages of PNALI.

Radiation therapy increases the risk of hepatobiliary complications in short bowel syndrome

Patients developing short bowel syndrome (SBS) are at risk for hepatobiliary complications. Radiation enteritis and radiation-induced liver disease are potential complications of radiation therapy (XRT). The authors hypothesized that SBS patients with a history of abdominal XRT would be at increased risk for hepatobiliary complications.

METHODS

The authors reviewed 92 adult patients developing SBS as a complication of operation for malignancy (n = 37) and/or XRT (n = 55). Hepatobiliary disease was evaluated by liver function tests, radiologic imaging, endoscopy, and histologic studies.

RESULTS

Rectal cancer was the most frequent tumor in both groups (36% vs 35%). There were significantly more ovarian cancers (18% vs 3%, P < .05) in the radiation group and fewer desmoid tumors (0% vs 24%, P < .05). Intestinal remnant length was similar, but radiation patients more frequently had colon present (87% vs 62%, P < .05) and were less likely to have type I anatomy (33% vs 65%, P < .05). Radiation patients were less likely to be weaned off parenteral nutrition (PN; 16% vs 41%, P < .05). Cirrhosis/portal hypertension was more frequent in the radiation group (35% vs 11%, P < .05). Radiographic evidence of fatty liver, end-stage liver disease and the risk of cholelithiasis post-SBS were similar in both groups.

CONCLUSIONS

SBS patients with a history of XRT were more likely to develop cirrhosis and portal hypertension than SBS patients with malignancy alone. Radiation SBS patients were less likely to wean from PN despite more favorable intestinal anatomy.

Short-term use of parenteral nutrition with a lipid emulsion containing a mixture of soybean oil, olive oil, medium-chain triglycerides, and fish oil: a randomized double-blind study in preterm infants

BACKGROUND

For premature neonates needing parenteral nutrition (PN), a balanced lipid supply is crucial. The authors hypothesized that a lipid emulsion containing medium-chain triglycerides (MCTs) and soybean, olive, and fish oils would be as safe and well tolerated as a soybean emulsion while beneficially influencing the fatty acid profile.

METHODS

Double-blind, controlled study in 53 neonates (<34 weeks' gestation) randomized to receive at least 7 days of PN containing either an emulsion of MCTs and soybean, olive, and fish oils or a soybean oil emulsion. Target lipid dosage was 1.0 g fat/kg body weight [BW]/d on days 1-3, 2 g/kg BW/d on day 4, 3 g/kg BW/d on day 5, and 3.5 g/kg BW/d on days 6-14.

RESULTS

Test emulsion vs control, mean ± SD: baseline triglyceride concentrations were 0.52 ± 0.16 vs 0.54 ± 0.19 mmol/L and increased similarly in both groups to 0.69 ± 0.38 vs 0.67 ± 0.36 on day 8 of treatment (P = .781 for change). A significantly higher decrease in total and direct bilirubin vs baseline was seen in the test group compared with the control group P < .05 between groups). In plasma and red blood cell phospholipids, eicosapentaenoic acid and docosahexaenoic acid were higher, and the n-6/n-3 fatty acid ratio was lower in the test group (P < .05 vs control).

CONCLUSIONS

The lipid emulsion, based on a mixture of MCTs and soybean, olive, and fish oils, was safe and well tolerated by preterm infants while beneficially modulating the fatty acid profile.

The impact of MELD/PELD revisions on the mortality of liver-intestine transplantation candidates

Patients listed for liver-intestine transplantation suffer higher waiting list mortality than those listed for liver-only, thus leading to policy revisions seeking to close the gap. We sought to determine the impact of key model for end-stage liver disease (MELD)/pediatric end-stage liver disease (PELD) policy modifications on the waiting list mortality of adult and pediatric liver-intestine candidates as compared to liver-only candidates. Analysis of UNOS data separated into adult and pediatric categories and based on time periods of policy implementation revealed higher mortality in liver-intestine candidates over all time periods studied (p < 0.001 pediatric and adult). After implementation of a revision to augment their MELD scores based on a sliding scale, adult liver-intestine candidates with calculated MELD > 15 no longer suffered higher mortality although this change did not completely eliminate the mortality disparity for candidates with MELD < 15 (p < 0.01). The waiting list mortality of pediatric liver-intestine candidates dropped significantly after a revision that gave them 23 additional MELD/PELD points (p < 0.01) although the mortality disparity with pediatric liver-only candidates was not eliminated. Following this revision, mortality in pediatric liver-only and liver-intestine Status 1 candidates was similar, however more liver-intestine candidates were listed as Status 1B. This data demonstrates that a mortality disparity remains for liver-intestine candidates compared with candidates listed for liver-only.

Intestinal transplantation: current status and future directions

Three decades after the first intestinal transplant was performed in humans, this life-saving procedure has come of age and now offers hope of long-term survival in a small group of patients with life-threatening complications of intestinal failure and parenteral nutrition. Success rates have greatly improved, largely through advances in immunosuppression protocols, improved surgical technique and postoperative care, and accumulated experience. Management of the intestinal transplant recipient entails careful surveillance, prevention, and treatment of rejection and infection, as well as optimization of feeding and nutrition. With this approach, survival and quality of life are demonstrably improved, such that intestinal transplantation is now an established and accepted procedure for this very select group of highly-complex patients.

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.

Safety and efficacy of a lipid emulsion containing a mixture of soybean oil, medium-chain triglycerides, olive oil, and fish oil: a randomised, double-blind clinical trial in premature infants requiring parenteral nutrition

OBJECTIVES

Safety, tolerability, and efficacy of a novel lipid emulsion containing a mixture of soybean oil, medium-chain triglycerides, olive oil, and fish oil (SMOFlipid 20%) with reduced n-6 fatty acids (FA), increased monounsaturated and n-3 FA, and enriched in vitamin E were evaluated in premature infants compared with a soybean oil-based emulsion.

PATIENTS AND METHODS

Sixty (30/30) premature neonates (age 3-7 days, gestational age ≤ 34 weeks, birth weights 1000-2500 g) received parenteral nutrition (PN) with either SMOFlipid 20% (study group) or a conventional lipid emulsion (Intralipid 20%, control group) for a minimum of 7 up to 14 days. Lipid supply started at 0.5 g · kg body weight(-1) · day(-1) on day 1 and increased stepwise (by 0.5 g) up to 2 g · kg body weight(-1) · day(-1) on days 4 to 14. Safety and efficacy parameters were assessed on days 0, 8, and 15 if PN was continued.

RESULTS

Adverse events, serum triglycerides, vital signs, local tolerance, and clinical laboratory did not show noticeable group differences, confirming the safety of study treatment. At study end, γ-glutamyl transferase was lower in the study versus the control group (107.8 ± 81.7 vs 188.8 ± 176.7 IU/L, P < 0.05). The relative increase in body weight (day 8 vs baseline) was 5.0% ± 6.5% versus 5.1% ± 6.6% (study vs control, not significant). In the study group, an increase in n-3 FA in red blood cell phospholipids and n-3:n-6 FA ratio was observed. Plasma α-tocopherol (study vs control) was increased versus baseline on day 8 (26.35 ± 10.03 vs 3.67 ± 8.06 μmol/L, P < 0.05) and at study termination (26.97 ± 18.32 vs 8.73 ± 11.41 μmol/L, P < 0.05).

CONCLUSIONS

Parenteral infusion of SMOFlipid was safe and well tolerated and showed a potential beneficial influence on cholestasis, n-3 FA, and vitamin E status in premature infants requiring PN.

Serum B12 concentration is elevated in patients receiving chronic parenteral nutrition, but is not a marker of intestinal failure-associated liver disease

BACKGROUND

Cobalamin is released during hepatic cytolysis associated with liver injury. Serum B12 concentration is frequently elevated in patients that receive long-term parenteral nutrition (PN). We hypothesized that serum B12 concentration would become elevated in intestinal failure-associated liver disease and would reflect in disease severity.

METHODS

We retrospectively evaluated 13 patients with short bowel syndrome (<200 cm residual small intestine) that included complete terminal ileum resection (3 male and 10 female, aged 42 to 78 y) that had received parenteral nutrition (PN) 6.1+/-3 years. All 13 patients had received at least 1 liver biopsy for presumed intestinal failure-associated liver disease. At the time of biopsy, patients had received PN between 2 and 7 days a week (4.7+/-1.9 d). The liver biopsies were evaluated and prospectively scored for pathology using 3 independent scoring systems validated for nonalcoholic steatohepatitis and nonalcoholic fatty liver disease [Brunt, NAFLD activity score (NAS) and Dixon methods], whereby numeric values were assigned to degrees of steatosis, inflammation, and fibrosis. Serum B12 concentration and hepatic chemistries (aspartate transaminase, alanine transaminase, alkaline phosphatase, and bilirubin) were recorded within 1 week of the biopsies.

RESULTS

Thirteen biopsies were available for analysis. Serum B12 concentration and hepatic chemistries were available for all biopsy times. The mean serum B12 concentration was 619+/-222 pg/mL. The mean daily parenteral B12 dose was 3.3+/-1.3 mcg. Mean NAS, Brunt, and Dixon scores were 2, 1, and 1, respectively. The Spearman correlation coefficients between serum B12 concentration and liver biopsy scores were 0.15, 0.1, and 0.1 for the NAS, Brunt, and Dixon scores, respectively, indicating that there was no correlation between serum B12 concentration and liver pathology. The Spearman correlation coefficient between the NAS inflammation subscore and serum B12 concentration was 0.02. B12 concentration also failed to correlate with hepatic chemistries. There was surprisingly little correlation between serum B12 concentration and exogenous B12 daily dose through PN (r=0.19, P=0.45).

CONCLUSIONS

Elevated serum B12 concentration is commonly encountered in patients who receive long-term parenteral nutrition. This does not seem to be an indicator of hepatic pathology; rather it may reflect the provision of excessive intravenous vitamin B12 and other as yet unknown factors.

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.

Rapid reversal of parenteral-nutrition-associated cirrhosis following isolated intestinal transplantation

INTRODUCTION

Liver disease and the development of hepatic fibrosis are complications associated with total parenteral nutrition (TPN). Patients developing cirrhosis and portal hypertension in the setting of intestinal failure have a high mortality and may require combined liver and intestinal transplantation which carries much higher morbidity and mortality than isolated intestinal transplantation.

DISCUSSION

Recently, regression of hepatic fibrosis in patients with TPN liver disease has been described following intestinal transplantation. To date, there has been no demonstration of the reversal of established cirrhosis due to long-term TPN injury. Herein, we describe a patient with intestinal failure who developed cirrhosis from long-standing TPN injury and underwent isolated intestinal transplantation. He had no overt clinical stigmata of portal hypertension and had preserved liver function. Serial liver biopsies were reviewed and assessed with standard histology and quantitation of fibrosis using image analysis. Dramatic regression of fibrosis and reversal of cirrhosis were observed 17 months posttransplantation. Image analysis demonstrated a 14% total decrease in the percentage area of fibrosis.

CONCLUSIONS

Cirrhosis related to TPN may be rapidly reversible after isolated intestinal transplantation. Such patients may be able to undergo isolated intestinal transplantation if they do not have hepatic synthetic compromise or clinical stigmata of portal hypertension.

Frequency of mitochondrial defects in patients with chronic intestinal pseudo-obstruction

BACKGROUND & AIMS

Chronic intestinal pseudo-obstruction (CIPO) is a rare disorder caused by intestinal dysmotility and characterized by chronic symptoms suggesting bowel obstruction in the absence of fixed, occluding lesions. CIPO has been associated with primary defects of the mitochondrial oxidative phosphorylation pathway, although the frequency of mitochondrial disorders in patients with CIPO is unknown. This study evaluates mitochondrial function in patients with CIPO.

METHODS

A retrospective study was performed of data collected from 80 CIPO patients at a tertiary centre over a 25-year period. Mitochondrial disorders were detected by analysis of serum lactate and thymidine phosphorylase activities, brain magnetic resonance images, and muscle biopsies. Genes encoding thymidine phosphorylase, mitochondrial DNA tRNA(leu(UUR)) or tRNA(lys), and DNA polymerase-gamma were analyzed for mutations.

RESULTS

Mitochondrial defects were identified in 15 patients (10 women; median age at diagnosis 32 years), representing 19% of the study cohort. All 15 patients had extra-digestive symptoms, 5 had mutations in the thymidine phosphorylase gene, 2 had mutations in tRNA(leu(UUR)), and 5 had mutations in the DNA polymerase-gamma gene. No genetic defect was detected in 3 of the patients with mitochondrial disorders. Patients with mitochondrial CIPO differed from patients without mitochondrial defects in their very severe nutritional status (frequent and long-term requirement for parenteral nutrition) and poor prognosis (frequent digestive and neurologic complications that led to a high incidence of premature death).

CONCLUSION

Mitochondrial disorders seem to be an important cause of CIPO. Patients with CIPO, especially severe cases with associated neurologic symptoms, should be tested for mitochondrial defects.

Allograft steatohepatitis in progressive familial intrahepatic cholestasis type 1 after living donor liver transplantation

We studied histological features and long-term outcomes in patients with progressive familial intrahepatic cholestasis type 1 (PFIC1) after liver transplantation (LT). Histological findings were correlated with the post-LT course and treatment in 11 recipients with PFIC1. Ages at LT varied from 1 to 18 years (median, 4 years). Macrovesicular steatosis was observed in 8 patients at a median of 60 days post-LT (range, 21-191 days). Severe steatosis progressed to steatohepatitis in 7 patients at a median of 161 days (range, 116-932 days). The patients were followed up for a median of 7.3 years (range, 2.3-16.1 years). Six showed bridging fibrosis, with 2 progressing to cirrhosis. One patient with cirrhosis died because of the rupture of a splenic artery aneurysm 13.6 years post-LT. Post-LT refractory diarrhea was present in all 8 having steatosis. Three without post-LT diarrhea showed no allograft steatosis. Bile adsorptive resin therapy reduced the diarrhea and steatosis. Patients with posttransplant steatosis typically had more severe mutations of the ATPase class I type 8B member 1 (ATP8B1) gene and were more likely to have systemic complications such as pancreatitis. In conclusion, allograft steatosis was present in patients with PFIC1, progressing to steatohepatitis and cirrhosis. Because expression of the familial intrahepatic cholestasis 1 gene occurs in several organs, including the small intestine, pancreas, and liver, and it is involved in enterohepatic bile acid circulation, post-LT steatosis may be due to a malfunction of the ATP8B1 product.

Melatonin protects liver from intestine ischemia reperfusion injury in rats

AIM: To investigate the protective effect of melatonin on liver after intestinal ischemia-reperfusion injury in rats.

METHODS: One hundred and fifty male Wistar rats, weighing 190-210 g, aged 7 wk, were randomly divided into melatonin exposure group, alcohol solvent control group and normal saline control group. Rats in the melatonin exposure group received intraperitoneal (IP) melatonin (20 mg/kg) 30 min before intestinal ischemia-reperfusion (IR), rats in the alcohol solvent control group received the same concentration and volume of alcohol, and rats in the normal saline control group received the same volume of normal saline. Serum samples were collected from each group 0.5, 1, 6, 12, and 24 h after intestinal IR. Levels of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured with an auto-biochemical analyzer. Serum TNF-α was tested by enzyme-linked immunosorbent assay (ELISA). Malondialdehyde (MDA) in liver was detected by colorimetric assay. Pathological changes in liver and immunohistochemical straining of ICAM-1 were observed under an optical microscope.

RESULTS: The levels of ALT measured at various time points after intestinal IR in the melatonin exposure group were significantly lower than those in the other two control groups (P < 0.05). The serum AST levels 12 and 24 h after intestinal IR and the ICAM-1 levels (%) 6, 12 and 24 h after intestinal IR in the melatonin exposure group were also significantly lower than those in the other two control groups (P < 0.05).

CONCLUSION: Exotic melatonin can inhibit the activity of ALT, AST and TNF-α, decrease the accumulation of MDA, and depress the expression of ICAM-1 in liver after intestinal IR injury, thus improving the liver function.

Survival of patients identified as candidates for intestinal transplantation: a 3-year prospective follow-up

BACKGROUND & AIMS

The US Medicare indications for intestinal transplantation are based on failure of home parenteral nutrition. The American Society of Transplantation also includes patients at high risk of death from their primary disease or with high morbidity intestinal failure. A 3-year prospective study evaluated the appropriateness of these indications.

METHODS

Survival on home parenteral nutrition or after transplantation was analyzed in 153 (97 adult, 56 pediatric) candidates for transplantation and 320 (262 adult, 58 pediatric) noncandidates, enrolled through a European multicenter cross-sectional survey performed in 2004. Kaplan-Meier and chi-square test statistics were used.

RESULTS

The 3-year survival was 94% (95% CI, 92%-97%) in noncandidates and 87% (95% CI, 81%-93%) in candidates not receiving transplants (P = .007). Survival was 80% (95% CI, 70%-89%), 93% (95% CI, 86%-100%), and 100% in parenteral nutrition failure, high-risk primary disease, and high-morbidity intestinal failure, respectively (P = .034). Fifteen candidates underwent transplantation. Six died, including all 3 of those who were in hospital, and 25% of those who were at home at time of transplantation (P = .086). Survival in the 10 patients receiving a first isolated small bowel transplant was 89% (95% CI, 70%-100%), compared with 85% (95% CI, 74%-96%) in the candidates with parenteral nutrition failure not receiving transplants because of central venous catheter complications, or 70% (95% CI, 53%-88%) in those with parenteral nutrition-related liver failure (P = .364).

CONCLUSIONS

The results confirm home parenteral nutrition as the primary therapeutic option for intestinal failure and support the appropriateness and potential life-saving role of timely intestinal transplantation for patients with parenteral nutrition failure.

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.

Intestinal transplantation: current status

Intestine transplant is indicated for patients with intestinal failure who are unable to be weaned from parenteral nutrition (PN). Long-term PN, although life sustaining in many patients, can be associated with life-threatening complications including PN-associated liver disease (PNALD). Most patients are not considered for intestine transplant until they have developed severe PNALD and also need a liver transplant. Overall outcomes with intestinal transplantation are steadily improving, and current 1-year patient survivals for intestine-only transplants are now similar to those for liver transplant. Intestinal transplantation should be considered earlier in intestinal failure patients who are at high risk for developing PNALD and other life-threatening complications.

The establishment of a new en bloc combined liver-small bowel transplantation model in rats

In order to facilitate preclinical research, we established a new combined liver-small bowel transplantation rat model. Male inbred Wistar rats were chosen as donors and recipients. An en bloc liver-small bowel graft was harvested. During the donor operation, the inferior vena cava in the chest was removed to be used as an interpositional venous graft to anastomose to the portal vein. In the recipient operation the portal veins of donor and recipient were quickly anastomosed using a cuff technique instead of the traditional suture method. Rearterialization was achieved by anastomosing the superior mesenteric artery of graft to the right renal artery of the recipient. The recipient small bowel was resected and intestinal continuity restored simultaneously by two end-to-end anastomoses. The postoperative 5-day survival rate was 77.5% (31/40) and 60-day survival rate, 72.5% (29/40). Recipient rats that tolerated the operation remained healthy. Liver and renal function was normal. The liver and intestinal grafts showed normal histological architecture in all rats surviving for 2 months postoperatively. Our results demonstrated that the present model is feasible, allowing preclinical experimental research on combined liver-small bowel transplantation.

Immuno-protective effect of liver on small bowel in combined transplantation of liver and small bowel

AIM: To develop a new combined transplan-tation model of liver and small bowel in rats, and to investigate the protective effect of trans-planted liver on transplanted small bowel.

METHODS: Closed colony Sprague Dawley rats and inbred Wistar rats were included in this study. Five groups were designed: isogene small bowel transplant group (A), isogene liver transplant group (B), xenogene small bowel transplant group (C), xenogene liver transplant group (D), combined transplant of liver and small bowel group (E). Only Wistar rats were used in group A and B, while SD and Wistar rats were used as donors and recipients respectively in group C, D and E. During the combined transplantation of liver and small bowel (CTLS) for the donors, inferior vena cava in chest was cut to construct a muff in the lateral wall of portal vein and cuff was placed. During the operation for the recipients, portal veins of the donors and recipients were connected using cuff technique, and re-arterialization was completed by anastomosing the superior mesenteric artery of graft with the right kidney artery of the recipients. Randomly selected 4 rats from each group were sacrificed on postoperative days (POD) 5, 7 and 14, and grafts were sampled. The rejection of graft was investigated through histopathological analysis, and the apoptosis of the cells of graft were evaluated by TUNEL.

RESULTS: The survival rate of CTLS was 73.3% (22/30). The pathological changes of ischemia and reperfusion injury were observed in group A and B, and the numbers of apoptotic cells in the grafts were decreased with the prolonging of time. However, acute rejection after transplantation appeared in group C and D, and there were more apoptotic cells in the grafts. Mild, moderate and severe acute rejection occurred on POD 5, 7 and 14, respectively in group C, while only mild or severe acute rejection appeared in group E. Furthermore, the number of apoptotic cells in the grafts of group E was markedly decreased on POD 14 in comparison with that of group C (16.9 ± 4.3 vs 20.5 ± 6.3, P < 0.05). The degrees of acute rejection after transplantation and cell apoptosis of the grafts were not significantly different between group D and E.

CONCLUSION: The technique used in this study is feasible for establishment of CTLS model, and the transplanted liver can protect the transplanted intestinal graft from rejection in CTLS.