Parenteral nutrition-associated cholestasis in preterm neonates: evaluation of ursodeoxycholic acid treatment

Natural bioactive compounds-The promising candidates for the treatment of intestinal failure-associated liver disease

Parenteral nutrition (PN) is a life-saving procedure conducted to maintain a proper nutritional state in patients with severe intestinal failure who cannot be fed orally. A serious complication of PN therapy is liver failure, known as intestinal failure-associated liver disease (IFALD). The pathogenesis of IFALD is multifactorial and includes inhibition of the farnesoid X receptor (FXR) by PN components, bacteria translocation from impaired intestines, and intravenous line-associated bloodstream infection. Currently, the most frequently researched therapeutic option for IFALD is using lipid emulsions based on soy or fish oil and, therefore, free from phytosterols known as FXR antagonists. Nevertheless, the potential side effects of the lack of soybean oil delivery seem to outweigh the benefits, especially in the pediatric population. PN admixture provides all the necessary nutrients; however, it is deprived of exogenous natural bioactive compounds (NBCs) of plant origin, such as polyphenols, characterized by health-promoting properties. Among them, many substances have already been known to demonstrate the hepatoprotective effect in various liver diseases. Therefore, searching for new therapeutic options for IFALD among NBCs seems reasonable and potentially successful. This review summarizes the recent research on polyphenols and their use in treating various liver diseases, especially metabolic dysfunction-associated steatotic liver diseases (MASLD). Furthermore, based on scientific reports, we have described the molecular mechanism of action of selected NBCs that exert hepatoprotective properties. We also summarized the current knowledge on IFALD pathogenesis, described therapeutic options undergoing clinical trials, and presented the future perspective of the potential use of NBCs in PN therapy.

Ursodeoxycholic acid use in lactating female patients is associated with clinically negligible concentrations of this bile acid in breast milk

In the literature on the safety of ursodeoxycholic acid (UDCA) during breastfeeding, insufficient data has been reported to date. Thus, the aim of our study was to analyze bile acid (BA) concentrations in breast milk in a cohort of patients, treated with UDCA, and with various cholestatic liver diseases. The study was carried out on a cohort of 20 patients with various cholestatic diseases. All the patients were treated with UDCA (500-1500 mg daily). Concentrations of BA, sampled on day 3 after delivery were analyzed using the GS-MS technique, and then compared to untreated women. Total BA concentrations in the breast milk of the UDCA-treated patients were equal to those of the untreated women controls (3.2 ± 1 vs. 3.2 ± 0.2 µmol/L, respectively). The UDCA concentrations in breast milk remained negligible in UDCA-treated patients (0.69 µmol/L), and in any event did not contribute to the newborn BA pool. No apparent side-effects of the maternal UDCA treatment were observed in any newborn infant, and no deterioration in postnatal development was observed during the routine 1-year follow-ups. Therapeutic administration of UDCA during lactation is safe for breastfed babies since UDCA only gets into breast milk in negligible amounts. UDCA treatment should be allowed and included into the guidelines for the therapy of cholestatic diseases in breastfeeding mothers.

IFALD in children: What's new? A narrative review

Intestinal failure-associated liver disease (IFALD) is a progressive liver disease complicating intestinal failure (IF). It is a preventable and reversible condition, but at the same time, a potential cause of liver cirrhosis and an indication to combined or non-combined liver and small bowel transplantation. The diagnostic criteria are not yet standardized, so that its prevalence varies widely in the literature. Pathophysiology seems to be multifactorial, related to different aspects of intestinal failure and not only to the long-term parenteral nutrition treatment. The survival rates of children with IF have increased, so that the main problems today are preventing complications and ensuring a good quality of life. IFALD is one of the most important factors that limit long-term survival of patients with IF. For this reason, more and more interest is developing around it and the number of published articles is increasing rapidly. The purpose of this narrative review was to focus on the main aspects of the etiology, pathophysiology, management, prevention, and treatment of IFALD, based on what has been published mainly in the last 10 years. Controversies and current research gaps will be highlighted with the aim to pave the way for new project and high-quality clinical trials.

Effect of Phenobarbital on Elevated Direct Bilirubin Concentrations in Neonates and Infants in the Neonatal Intensive Care Unit

OBJECTIVE

Few studies have evaluated the effect of phenobarbital (PB) on elevated direct bilirubin (DB) plasma concentrations in neonates and infants, and none have compared its effect with a control group with matched study baseline DB values. The purpose of this study was to quantify changes in elevated DB plasma concentrations (≥2 mg/dL) in neonates and infants between a PB-treated and control group.

METHODS

A retrospective, observational, matched, cohort study was performed comparing patients between a PB-treated group and a control group with similar study baseline plasma DB values ≥2 mg/dL over an 8-week period. The percent change in DB plasma concentrations from study baseline was compared for each week of the study period.

RESULTS

During the 8-year study period, 310 patients had DB plasma concentrations ≥2 mg/dL, of which 26 remained in each group after exclusions. The PB group had increased DB concentrations and the control group had decreased DB concentrations when compared with their study baseline DB concentrations each week of the study period. By study end, the mean DB concentration increased by 11.2% in the PB group and decreased by 48.5% in the control group (p = 0.02). In multiple regression analysis, only birth weight (standardized coefficient = 0.44, p = 0.02), and gastrointestinal obstruction (standardized coefficient = −0.4, p = 0.03) were associated with significant percent change in DB concentrations.

CONCLUSIONS

This study demonstrated PB does not improve cholestasis in neonates and infants.

Ursodeoxycholic acid prevention on cholestasis associated with total parenteral nutrition in preterm infants: a randomized trial

BACKGROUND

Preterm infants with long-term parenteral nutrition (PN) therapy are at risk for cholestasis associated with total parenteral nutrition (PNAC). This study examined the safety and efficacy of ursodeoxycholic acid (UDCA) in preventing PNAC in preterm infants. Our research aimed to investigate the prophylactic effect of preventive oral UDCA on PNAC in preterm infants.

METHODS

We compared oral administration of UDCA prophylaxis with no prophylaxis in a randomized, open-label, proof-of-concept trial in preterm neonates with PN therapy. The low-birth-weight preterm infants (< 1800 g) who were registered to the neonatal intensive care unit (NICU) within 24 hours after birth were randomized. The main endpoint was the weekly values of direct bilirubin (DB) of neonates during the NICU stay.

RESULTS

Eventually, a total of 102 preterm neonates from January 2021 to July 2021 were enrolled in this prospective study (42 in the UDCA group and 60 in the control group). Notably, the peak serum level of DB [13.0 (12-16) vs. 15.2 (12.5-19.6) μmol/L, P < 0.05)] was significantly lower in the UDCA group than that in the control group without prevention. The peak serum level of total bilirubin (101.1 ± 34 vs. 116.5 ± 28.7 μmol/L, P < 0.05) was also significantly lower in the UDCA group than in the control group. Furthermore, the proportion of patients who suffered from neonatal cholestasis (0.0% vs. 11.7%, P < 0.05) in the UDCA group was significantly lower.

CONCLUSION

UDCA prophylaxis is beneficial in preventing PNAC in NICU infants receiving prolonged PN.

Effect of ursodeoxycholic acid in facilitating early hepatic clearance of radiotracer among patients undergoing 99mTc-sestamibi myocardial perfusion scintigraphy: A randomized double blind placebo controlled parallel trial

BACKGROUND

Infra-cardiac tracer activity due to persistent hepatic activity interferes in inferior and infero-septal wall assessment during 99mTc-MIBI SPECT/CT myocardial perfusion scintigraphy (MPS) in evaluation of patients with coronary artery disease. It affects image interpretation with increased study duration. Ursodeoxycholic acid (UDCA) is known to enhance hepatic excretion of bilirubin and bile salts, though its role in enhancing the hepatic tracer clearance in facilitating cardiac imaging is not known.

METHODS

This prospective, randomized double-blind, placebo controlled clinical trial of 120 patients, referred for adenosine stress or viability MPS studies were randomized 1:1 to receive either UDCA or placebo. Outcome was quantitative & qualitative improvement in imaging for better interpretation and to reduce the waiting time for scan.

RESULTS

118 participants (59 ± 11.9 years; 84 men) underwent adenosine stress MPS or viability MPS. Sixty participants had UDCA while 58 had placebo intervention. The study showed significant decrease in liver counts with improved myocardial to liver ratio at 30 and 60 minutes in adenosine stress MPS group, and marginally significant alteration in liver counts at 60 minutes in viability MPS group receiving UDCA, resulting in better images.

CONCLUSION

UDCA intervention in MPS provides early and better image due to faster hepatic tracer clearance.

Effect of bile acid supplementation on endogenous lipid synthesis in patients with short bowel syndrome: A pilot study

BACKGROUND & AIMS

Short bowel syndrome patients (SBS) receiving parenteral nutrition (PN) often have dyslipidaemia and can develop intestinal failure-associated liver disease (IFALD). These patients demonstrate increased cholesterol synthesis and hepatic lipogenesis. These lipid disturbances may be due to a decreased concentration of the bile acid pool or malabsorption. The aim of this pilot study was to evaluate the effect of bile acid administration on lipid synthesis in patients with SBS.

METHODS

The 24 h fractional synthesis rate (FSR) of cholesterol and triglycerides was measured by the isotopic method (deuterated water) before and after 4 months of ursodeoxycholic acid (UDCA) treatment (20 mg/kg/day). Five short bowel patients (age: 53.4 ± 19.2 years) who had normal liver function and lipid plasmatic profiles received 1920 ± 300 ml of PN for 151 ± 74 days (mean PN energy intake was 27.0 ± 6.0 kcal/kg body weight, composed with 3.87 ± 1.38 g/kg of carbohydrate, 0.72 ± 0.25 g/kg of fat and 1.10 ± 0.23 g/kg of amino acids). Plasma metabolites, liver enzymes, 7-α-OH-cholesterol and steatosis levels were also evaluated before and after treatment. Student's t-tests were performed, and the results were expressed in means (±SD).

RESULTS

After treatment, decreases in the absolute values of cholesterol synthesis (0.31 ± 0.12 mmol L^-1 to 0.24 ± 0.11 mmol L^-1; p < 0.05), FSR of cholesterol (31.6 ± 4.7% to 26.4 ± 4.7%; p = 0.06) and FSR of triglycerides (12.8 ± 5.8% to 9.2 ± 5.5%; p < 0.01) were observed. Cholesterol and alanine aminotransferase concentrations also decreased (ALT) (p < 0.05). The absolute values of triglyceride synthesis and triglyceride concentrations remained unchanged.

CONCLUSIONS

In SBS patients, UDCA decreases the hepatic synthesis of triglycerides and cholesterol. These results suggest that UDCA could prevent the onset of the IFALD.

Visceral transplantation in patients with intestinal-failure associated liver disease: Evolving indications, graft selection, and outcomes

Intestinal failure (IF)-associated liver disease (IFALD) is widely recognized as a lethal complication of long-term parenteral nutrition. The pathophysiology of IFALD is poorly understood but appears to be multifactorial and related to the inflammatory state in the patient with IF. Visceral transplant for IFALD includes variants of intestine, liver, or combined liver-intestine allografts. Graft selection for an individual patient depends on the etiology of IF, abdominal and vascular anatomy, severity of IFALD, and potential for intestinal rehabilitation. The past decade has witnessed dramatic improvement in the management of IFALD, principally due to improved lipid emulsion formulations and the multidisciplinary care of the patient with IF. As the recognition and treatment of IFALD continue to improve, the requirement of liver-inclusive visceral grafts appears to be decreasing, representing a paradigm shift in the care of the patient with IF. This review highlights the current indications, graft selection, and outcomes of visceral transplantation for IFALD.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Liver disease secondary to intestinal failure

IFALD is a common and potentially life-threatening condition for patients with SBS requiring long-term PN. There exists the potential for decreasing its incidence by optimizing the composition and the rate of infusion of parenteral solutions, by advocating a multidisciplinary approach, and by early referral for intestinal-liver transplantation to ensure long-term survival of patients with SBS.

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.

Incidence, prevention, and treatment of parenteral nutrition-associated cholestasis and intestinal failure-associated liver disease in infants and children: a systematic review

BACKGROUND

Cholestasis is a significant life-threatening complication in children on parenteral nutrition (PN). Strategies to prevent/treat PN-associated cholestasis (PNAC) and intestinal failure-associated liver disease (IFALD) have reached moderate success with little supporting evidence. Aims of this systematic review were (1) to determine the incidence of PNAC/IFALD in children receiving PN for ≥ 14 days and (2) to review the efficacy of measures to prevent/treat PNAC/IFALD.

METHODS

Of 4696 abstracts screened, 406 relevant articles were reviewed, and studies on children with PN ≥ 14 days and cholestasis (conjugated bilirubin ≥ 2 mg/dL) were included. Analyzed parameters were (1) PNAC/IFALD incidence by decade and by PN length and (2) PNAC/IFALD prevention and treatment (prospective studies).

RESULTS

Twenty-three articles (3280 patients) showed an incidence of 28.2% and 49.8% of PNAC and IFALD, respectively, with no evident alteration over the last decades. The incidence of PNAC was directly proportional to the length of PN (from 15.7% for PN ≤ 1 month up to 60.9% for PN ≥ 2 months; P < .0001). Ten studies on PNAC met inclusion criteria. High or intermediate-dose of oral erythromycin and aminoacid-free PN with enteral whey protein gained significant benefits in preterm neonates (P < .05, P = .003, and P < .001, respectively). None of the studies reviewed met inclusion criteria for treatment.

CONCLUSIONS

The incidence of PNAC/IFALD in children has no obvious decrease over time. PNAC is directly correlated to the length of PN. Erythromycin and aminoacid-free PN with enteral whey protein have shown to prevent PNAC in preterm neonates. There is a lack of high-quality prospective studies, especially on IFALD.

Ω-3 fatty acids prevent hepatic steatosis, independent of PPAR-α activity, in a murine model of parenteral nutrition-associated liver disease

OBJECTIVES

ω-3 Fatty acids (FAs), natural ligands for the peroxisome proliferator-activated receptor-α (PPAR-α), attenuate parenteral nutrition-associated liver disease (PNALD). However, the mechanisms underlying the protective role of ω-3 FAs are still unknown. The aim of this study was to determine the effects of ω-3 FAs on hepatic triglyceride (TG) accumulation in a murine model of PNALD and to investigate the role of PPAR-α and microsomal triglyceride transfer protein (MTP) in this experimental setting.

METHODS

129S1/SvImJ wild-type or 129S4/SvJaePparatm/Gonz/J PPAR-α knockout mice were fed chow and water (controls); oral, fat-free PN solution only (PN-O); PN-O plus intraperitoneal (IP) ω-6 FA-predominant supplements (PN-ω-6); or PN-O plus IP ω-3 FA (PN-ω-3). Control and PN-O groups received sham IP injections of 0.9% NaCl. Hepatic histology, TG and cholesterol, MTP activity, and PPAR-α messenger RNA were assessed after 19 days.

RESULTS

In all experimental groups, PN feeding increased hepatic TG and MTP activity compared with controls. Both PN-O and PN-ω-6 groups accumulated significantly greater amounts of TG when compared with PN-ω-3 mice. Studies in PPAR-α null animals showed that PN feeding increases hepatic TG as in wild-type mice. PPAR-α null mice in the PN-O and PN-ω-6 groups demonstrated variable degrees of hepatic steatosis, whereas no evidence of hepatic fat accumulation was found after 19 days of oral PN plus IP ω-3 FAs.

CONCLUSIONS

PN induces TG accumulation (steatosis) in wild-type and PPAR-α null mice. In PN-fed wild-type and PPAR-α null mice given IP ω-3 FAs, reduced hepatic TG accumulation and absent steatosis are found. Prevention of steatosis by ω-3 FAs results from PPAR-α-independent pathways.

Das Frühgeborene

Die nekrotisierende Enterokolitis ist die klinisch wichtigste gastrointestinale Erkrankung des Neugeborenen, vor allem des Frühgeborenen. Selbst in der leichten Form stellt sie stets eine Notfallsituation dar. Neben schweren perakuten entzündlichen Veränderungen der Darmwand entstehen Koagulationsnekrosen, z. T. mit Perforationen. Betroffen sind vor allem das terminale Ileum und das angrenzende Kolon. Es kann aber der gesamte Gastrointestinaltrakt von der Erkrankung erfasst werden. Bislang gibt es keine eindeutige ätiologische Erklärung für die NEK, gleichwohl sind eine Reihe von pathogenetischen Risikofaktoren bekannt. Die Beschwerden können von Magenentleerungsstörungen und einem ausladenden Abdomen bis hin zu foudroyanten und letalen Verläufen reichen. Das therapeutische Vorgehen richtet sich nach der Schwere der Erkrankung: Nahrungskarenz, Entlastung des Gastrointestinaltrakts, antibiotische Therapie bis zur operativen Revision des betroffenen Darmabschnitts. Die Mortalität ist hoch, insbesondere bei extrem früh Geborenen.

A controlled trial of erythromycin and UDCA in premature infants during parenteral nutrition in minimizing feeding intolerance and liver function abnormalities

OBJECTIVE

To compare the effectiveness of oral erythromycin versus ursodeoxycholic acid (UDCA) treatment in preventing feeding intolerance and liver function abnormalities.

STUDY DESIGN

A prospective, double blind, randomized, controlled trial in which three groups of preterm infants (birth weight <1500 g) were randomized to erythromycin (12.5 mg kg(-1) per day), UDCA (5 mg kg(-1) every 6 h) or placebo treatment. During the period 352 infants were admitted to our unit of which 75 infants whose parents accepted participation were enrolled in the study. Full enteral feeding or intestinal failure-associated liver disease was considered as the primary outcome measures.

RESULTS

Time to achieve full feeding after beginning the treatment was significantly shorter in the erythromycin group (P=0.014). γ-Glutamyl transpeptidase levels in the placebo group were significantly higher than in the intervention groups (P=0.001). GTT level was slightly lower in UDCA groups than erythromycin.

CONCLUSION

Oral erythromycin was most effective in facilitating enteral feeding and UDCA was most effective in preventing cholestasis in very low birth weight infants. Prophylactic usage of UDCA could be considered in infants with prolonged parenteral nutrition.

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.

Systematic review: medical and nutritional interventions for the management of intestinal failure and its resultant complications in children

BACKGROUND

Intestinal failure (IF) affects a growing number of children due to increasing numbers of preterm infants surviving intestinal resection for necrotising enterocolitis and improving surgical techniques for congenital gut anomalies. Parenteral nutrition (PN) is the mainstay of therapy; enteral nutrition may have trophic effects on the gut.

AIM

To review systematically evidence for the effectiveness of medical and nutritional interventions in the treatment of IF in children.

METHODS

Retrieval of data from studies of patients aged <18 years and receiving >28 days of PN. Outcome measures were improvement in intestinal function, intestinal adaptation, growth, prevention and treatment of IF-associated liver disease, and mortality. Cochrane Database (November 2009), MEDLINE (1950-November 2009) and CINAHL (1982-November 2009) electronic database searches were made using keyword and subject headings (MeSH): IF, Short Bowel Syndrome (SBS), PN and Child. The level of the evidence (EL) was assessed using SIGN (Scottish Intercollegiate Guidelines Network) methodology (http://www.sign.ac.uk).

RESULTS

From 1 607 620 hits, 720 abstracts were reviewed. Thirty-three original articles were included. No studies were of high methodological quality.

CONCLUSIONS

The evidence base for medical and nutritional interventions in paediatric IF is limited and of poor quality. In the absence of randomised-controlled trials, this evidence base can improve through case control and cohort research; and with better multiagency communication, the study of inter-centre differences is possible. Achievable short-term goals would include the study of: optimal ursodeoxycholic usage, novel intralipid formulations, cycled enteral antibiotics, enteral probiotics and new enteral feeding strategies.

Collaborative strategies to reduce mortality and morbidity in patients with chronic intestinal failure including those who are referred for small bowel transplantation

Intestinal transplant wait-list mortality is higher than for other organ transplants. The objective of this workshop was to identify the main problems contributing to high mortality in adults and children candidates for intestinal transplantation and provide recommendations on how to correct them.

OUTCOME

To facilitate this, 63 relevant articles identified from the medical literature from 1987 to 2007 were reviewed. Consensus was achieved on several important definitions relevant to this review. For children and adults on parenteral nutrition (PN) the main mortality risk factors were identified as were the main risks of mortality for those on the waiting list for intestinal transplants.

RECOMMENDATIONS

(1) Primary care givers managing intestinal failure patients should establish a link with an intestinal failure programs early and collaboration with intestinal failure programs should be initiated for patients whose PN requirements are anticipated to be more than 50% 3 months after initiating PN; (2) intestinal failure programs should include both intestinal rehabilitation and intestinal transplantation or have active collaborative relationships with centers performing intestinal transplantation; (3) National registries for intestinal failure patients should be established and organizations that provide home PN solutions should be expected to participate.

CONCLUSION

There are many unresolved issues in adults and children with PN dependent intestinal failure. To address these, a key recommendation of this group is to establish national intestinal failure databases that can support multicenter studies and lead to the adoption of universally accepted standards of patient care with the goal of improving outcomes in all long-term intestinal failure patients including those requiring intestinal transplantation.

Ursodeoxycholic acid treatment in preterm infants: a pilot study for the prevention of cholestasis associated with total parenteral nutrition

In a prospective, double-blind, placebo-controlled trial, the efficacy and safety of ursodeoxycholic acid (UDCA) was evaluated in preterm infants, in terms of its potential impact on fat absorption, advancement of enteral feeding, development of cholestasis, growth, nutritional status, and metabolic status. Although fecal fat excretion slightly decreased and achievement of full enteral feeding was earlier in the UDCA group, these differences were not significant. Interestingly, whereas serum gamma-glutamyl transferase activity increased during the parenteral nutrition period in the placebo group, we observed a constant and significant decrease in the UDCA group. This observation warrants further investigation to determine the utility of prophylactic UDCA in preventing cholestasis in infants with prolonged parenteral nutrition.

Percutaneous cholangiography for the treatment of parenteral nutrition-associated cholestasis in surgical neonates: preliminary experience

OBJECTIVE

Parenteral nutrition-associated cholestasis (PNAC) occurs in up to 60% of surgical neonates with intestinal failure, and 10% will develop end-stage liver failure. Our aim was to evaluate the effectiveness of percutaneous transhepatic transcholecystic cholangiography (PTTC) in the treatment of PNAC in surgical neonates.

METHODS

A retrospective double cohort study of surgical neonates with PNAC was conducted. Patients with PNAC who received PTTC were compared to controls matched by gestational age, birth weight, sex, and parenteral nutrition duration. Percutaneous transhepatic transcholecystic cholangiography was performed under general anesthesia with ultrasound guidance. Analysis was performed using paired Student's t test and McNemar chi2 test.

RESULTS

Nine PTTC patients and 9 controls were similar in mean age (35.5 +/- 3.1 vs 35.6 +/- 4.2 weeks, P = .85), birth weight (2531 +/- 879 vs 2692 +/- 1052 g, P = .28), sex (all males), and parenteral nutrition duration (51.2 +/- 29.8 vs 53.3 +/- 33.3 days, P = .74). Percutaneous transhepatic transcholecystic cholangiography was performed in 9 patients at mean corrected age of 5.5 +/- 3.4 weeks and weight of 3621 +/- 546 g. All control patients and 8 (88.9%) of 9 PTTC patients had eventual resolution of hyperbilirubinemia. Percutaneous transhepatic transcholecystic cholangiography patients experienced a more rapid rate of resolution of their cholestasis, and the mean time to resolution of conjugated bilirubin was less in the PTTC group (8.5 +/- 3.2 vs 18.5 +/- 7.6 weeks, P = .02).

CONCLUSION

Therapeutic PTTC results in a 50% reduction in the time to PNAC resolution. Percutaneous transhepatic transcholecystic cholangiography may have a role as active therapy to slow progression of PNAC in surgical neonates with intestinal 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.

Parenteral nutrition related hepato-biliary disease in adults

Parenteral nutrition is a life-saving therapy in patients with intestinal failure. One of the major causes of morbidity and mortality in patients receiving long-term total parenteral nutrition (TPN) is liver disease. Early on, there is steatosis, which can evolve to steatohepatitis and eventually to cholestasis of varying severity. The etiology of parenteral nutrition related liver disease is multifactorial. Provision of excess calories in the TPN solution, along with lipids administered >1 g/kg are thought to increase the risk of parenteral nutrition related liver disease. Other factors such as nutrient deficiencies and nutrient toxicities may also play a role in the pathogenesis of liver disease, along with sepsis and the lack of enteral stimulation. Non-pharmacological management strategies for TPN-related liver disease include enteral stimulation, optimal TPN composition, and avoidance of excess carbohydrate and lipid calories. Pharmacological therapy with ursodeoxycholic acid and antibiotic therapy to reduce the risk of bacterial translocation and sepsis should be considered. Early referral for transplantation should be considered in patients with evidence of portal hypertension. This review focuses on the clinical aspects, pathogenesis, and management strategies of parenteral nutrition-related liver disease in adult patients.

Complications of parenteral nutrition

Parenteral nutrition plays a vital role for patients with intestinal failure and those who are unable to maintain oral or enteral nutrition alone. Parenteral nutrition has been shown to improve clinical outcome in patients with malnutrition and intestinal tract dysfunction. The use of parenteral nutrition is not without risk of serious complications. Parenteral nutrition complications can be divided into mechanical related to vascular access, septic, and metabolic. This article provides a review on the short- and long-term complications of parenteral nutrition and their management.

Criteria supporting the study of drugs in the newborn

BACKGROUND

Profound changes in the development and the maturation of neonates' organs and organ systems over variable periods of time potentially place neonates at increased risk and/or at different risks compared with adults or older children on exposure to pharmaceutical agents. Most studies of drugs in neonates focus on pharmacokinetic and pharmacodynamic end points and include insufficient numbers of patients to permit evaluation of safety. Only one fourth to one third of approved drugs have received adequate pediatric study to permit labeling for treatment of all appropriate pediatric populations.

OBJECTIVE

The initial goal of the Newborn Drug Prioritization Group was to develop a reproducible, objective process for evaluating drugs most in need of study in the neonatal population based on a universally acceptable priority ranking. The criteria would be applicable across therapeutic classes and would identify those drugs for which immediate study was most needed.

METHODS

Because the therapeutic requirements of the neonate are unique in comparison to older infants and children, the National Institute of Child Health and Human Development and the US Food and Drug Administration (FDA) developed the Newborn Drug Development Initiative to address the limited study of off-patent drugs in newborns. In March 2003, they convened a meeting of pediatric pharmacologists and pediatric specialists from the FDA, the American Academy of Pediatrics, the National Institutes of Health, and academic institutions to discuss how to increase the study of drugs for the newborn. One of the working groups was charged to develop generic criteria for overall prioritization of drugs for study in newborns. Because resources are limited, and not all drugs identified by the 4 clinically focused working groups can receive study at the same time, a process for priority ranking is necessary.

RESULTS

The panel identified 4 general categories containing different numbers of criteria as important for ranking drugs for priority investigation: (1) the disease and indication, including elements such as the potential for adverse outcomes, frequency in newborns, and level of evidence for treatment of newborns; (2) drug characteristics, including elements such as duration of dosing, lack of age-appropriate formulation, clinically relevant drug-drug and drug-disease interactions, and drug disposition in newborns; (3) feasibility and methodology for newborn studies, including both analytical considerations and clinical end points; and (4) the ethical basis for study, including elements to address benefit or harm due to exposure to the study drug, study methodology, and benefit of the new treatment relative to established standard therapy. Based on these categories, a list of criteria to warrant study of a drug in newborns was developed.

CONCLUSION

A process for judicious use of limited resources to rectify these deficiencies remains an urgent public health need.

Parenteral nutrition-associated liver disease in adult and pediatric patients

There are essentially 3 types of hepatobiliary disorders associated with parenteral nutrition (PN) therapy: steatosis, cholestasis, and gallbladder sludge/stones. Reported prevalence rates of PN-associated liver disease (PNALD) vary greatly, and there are distinct differences between adult and pediatric patients. Various etiologic factors have been evaluated for significance in contributing to PNALD, including enteral feeding history, septic events, bacterial overgrowth, length of intestinal resection, and prematurity/low birth weight. Etiologic factors specifically related to the PN formulation or nutrient intake have also been evaluated, including excessive calorie intake, dextrose-to-lipid ratio, amino acid dose, taurine deficiency, IV fat emulsion (IVFE) dose, carnitine deficiency, choline deficiency, and continuous vs cyclic infusion. Minor increases in serum aminotransferase concentrations are relatively common in patients receiving PN therapy and generally require no intervention. The primary indicator of cholestasis is a serum conjugated bilirubin >2 mg/dL. When a patient receiving PN develops liver complications, it is necessary to rule out all treatable causes and minimize other risk factors. All potential hepatotoxic medications and herbal supplements should be eliminated. Modifications to the PN regimen that may be helpful include reduction of calories, reduction of IVFE dose to <1 g/kg/d, supplementation of taurine in the infant, and use of cyclic infusion. Initiation of even small amounts of enteral nutrition and use of ursodiol may be beneficial in stimulating bile flow. In the long-term PN patient with severe and progressive liver disease, intestinal or liver transplantation may be the only remaining treatment option.

Early treatment with ursodeoxycholic acid for cholestasis in children on parenteral nutrition because of primary intestinal failure

BACKGROUND

There is conflicting evidence as to whether ursodeoxycholic acid (UDCA) reduces the incidence of parenteral nutrition-associated cholestasis.

AIM

To investigate the efficacy of UDCA on parenteral nutrition-associated cholestasis in children with intestinal failure due to short bowel syndrome or to other causes.

METHODS

Children with cholestasis received 30 mg/kg/day UDCA. Improvement or normalization of parenteral nutrition-associated cholestasis was evaluated at 6 months of therapy and at the last follow-up. In a subgroup of children, serum UDCA levels were measured while receiving UDCA and after 4 weeks withdrawal.

RESULTS

Twelve children were treated with UDCA. Full remission or partial improvement of parenteral nutrition-associated cholestasis occurred in 11 of 12 children. In three of four children, withdrawal of UDCA was associated with a rebound rise of cholestasis. Only one of 12 treated children showed no improvement and in this patient, in contrast to four other patients, plasma levels of UDCA did not increase during treatment.

CONCLUSIONS

Ursodeoxycholic acid was effective in controlling parenteral nutrition-associated cholestasis. The efficacy of UDCA also in children with short bowel is related to intestinal absorption.

Ursodeoxycholic Acid for the Treatment of Parenteral Nutrition–Associated Cholestasis in Pediatric Patients

Objective:

To determine the relative safety and efficacy of ursodeoxycholic acid (UDCA) in children and neonates with parenteral nutrition–associated cholestasis (PNAC).

Data Sources:

A comprehensive search (up to May 29, 2006) of the following databases was conducted to identify relevant prospective, randomized, double-blind clinical trials and systematic reviews: Ovid–MEDLINE, PubMed, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Abstracts of Reviews of Effects, and the Centre for Reviews and Dissemination. In addition, reference lists from retrieved articles were searched to identify trials or systematic reviews not identified in the search of electronic databases. Also, the manufacturer of UDCA was contacted regarding access to any other unpublished trials that could be included in this review.

Study Selection and Data Extraction:

Prospective, double-blind, randomized, controlled trials of neonates (<36 wk gestational age) and/or children (0–18 y) who developed PNAC while receiving parenteral nutrition were included in the analysis. Articles were evaluated with specific focus placed on the following hierarchy of outcomes: mortality, nonfatal serious adverse events, liver failure, infection, sepsis, return of liver function test results to within normal ranges, and relief of pruritus.

Data Synthesis:

No prospective, double-blind, randomized, controlled trials assessing the efficacy and safety of UDCA for the treatment of PNAC in children and/or neonates were identified. Five retrospective chart reviews and/or case series were identified; however, the results of these studies were conflicting and do not provide sufficient evidence of the safety and efficacy of UDCA for the treatment of PNAC.

Conclusions:

There is no evidence from prospective, double-blind, randomized, controlled trials in neonates and/or children with PNAC regarding the relative safety and efficacy of UDCA therapy.

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.

Bioequivalence of a new liquid formulation of ursodeoxycholic acid (Ursofalk suspension) and Ursofalk capsules measured by plasma pharmacokinetics and biliary enrichment

BACKGROUND

Ursodeoxycholic acid is an approved therapy for hepatobiliary disorders but in infants and children compliance is compromised because it is formulated exclusively as capsules, or tablets.

AIM

To determine the pharmacokinetics and bioequivalence of a new liquid formulation of ursodeoxycholic acid (Ursofalk suspension) with a standard capsule (Ursofalk) in a randomized, unblinded, crossover designed study of 24 healthy adults.

METHODS

Equivalence was based on single bolus oral plasma pharmacokinetics and biliary ursodeoxycholic acid enrichments after repeat doses. Biliary bile acid composition and hydrophobicity index were also compared. Ursodeoxycholic acid was measured in duodenal bile by high-performance liquid chromatography and in plasma by mass spectrometry.

RESULTS

The mean percentage biliary ursodeoxycholic acid enrichment after administration of the suspension was not significantly different from that obtained with capsules (44.2 +/- 11.7% vs. 46.9 +/- 10.2%, respectively). The equivalence ratio was 0.94 (95% CI: 0.8-1.1), establishing bioequivalence between suspension and capsules. Both formulations reduced the biliary hydrophobicity index and no differences in bile acid composition were observed between formulations. The plasma pharmacokinetics of both formulations was similar and the tolerability of the suspension was excellent.

CONCLUSIONS

A new liquid formulation of ursodeoxycholic acid suitable for paediatric patients is pharmacologically bioequivalent to capsules when given as single, or repeated oral doses.

Omega-3 fatty acid supplementation prevents hepatic steatosis in a murine model of nonalcoholic fatty liver disease

Prolonged use of total parenteral nutrition can lead to nonalcoholic fatty liver disease, ranging from hepatic steatosis to cirrhosis and liver failure. It has been demonstrated that omega-3 fatty acids are negative regulators of hepatic lipogenesis and that they can also modulate the inflammatory response in mice. Furthermore, they may attenuate hepatic steatosis even in leptin-deficient ob/ob mice. We hypothesized that omega-3 fatty acid supplementation may protect the liver against hepatic steatosis in a murine model of parenteral nutrition in which all animals develop steatosis and liver enzyme disturbances. For testing this hypothesis, groups of mice received a fat-free, high-carbohydrate liquid diet ad libitum for 19 d with enteral or i.v. supplementation of an omega-3 fatty acid emulsion or a standard i.v. lipid emulsion. Control mice received food alone or the fat-free, high-carbohydrate diet without lipid supplementation. Mice that received the fat-free, high-carbohydrate diet only or supplemented with a standard i.v. lipid emulsion developed severe liver damage as determined by histology and magnetic resonance spectroscopy as well as elevation of serum liver function tests. Animals that received an i.v. omega-3 fatty acid emulsion, however, showed only mild deposits of fat in the liver, whereas enteral omega-3 fatty acids prevented hepatic pathology and led to normalization of liver function tests. In conclusion, whereas standard i.v. lipid emulsions fail to improve dietary-induced steatotic injury to the liver, i.v. supplementation of omega-3 fatty acids partially and enteral supplementation completely protects the liver against such injury.

Liver disease due to parenteral and enteral nutrition

Liver disease due to parenteral and enteral nutrition is a well-recognized iatrogenic phenomenon, but its cause and pathogenesis have not been clearly elucidated. Various mechanisms have been postulated, but it is likely that the cause is multifactorial with significant interplay among several factors. A preventive approach to management is ideal but awaits a more complete understanding of the pathophysiology. A variety of management strategies has been proposed in small case series, but level 1 evidence-based guidelines have yet to be established. Although an abundance of both clinical and animal studies exist regarding liver disease associated with parenteral nutrition (PN), there is a paucity of data regarding enteral nutrition (EN)-associated hepatic disease. The latter probably reflects differences in the frequency and severity of PN- versus EN-associated liver disease. This article addresses the two routes of nutritional support individually, with the major focus on PN-associated liver disease.

Ursodeoxycholic acid (UDCA) therapy in very-low-birth-weight infants with parenteral nutrition-associated cholestasis

OBJECTIVE

To determine the effect of ursodeoxycholic acid (UDCA) in very-low-birth-weight (VLBW) infants with parenteral nutrition-associated cholestasis (PNAC).

STUDY DESIGN

A retrospective study of all VLBW infants with PNAC who were admitted to a tertiary referral center was conducted. Patients were classified as treatment group (receiving UDCA within 14 days after onset of cholestasis) or control group (no medical treatment). Patients who received abdominal surgery were excluded.

RESULTS

A total of 30 patients were recruited, including 12 in the treatment group and 18 in the control group. The demographic data, total fasting duration, onset of cholestasis, age to tolerance of full feeds, and the duration of parenteral nutrition (PN) before the onset of cholestasis were comparable between the two groups. There was a trend in the control group to later onset of cholestasis. The patients who received UDCA therapy with doses of 10 to 30 mg/kg/day had a shorter duration of cholestasis than the control group (62.8 vs 92.4 days, P=.006). Furthermore, the peak serum levels of direct bilirubin also was significantly lower in the treatment group.

CONCLUSION

UDCA can improve the course of PNAC in VLBW infants.

Tauroursodeoxycholic acid (TUDCA) in the prevention of total parenteral nutrition-associated liver disease

OBJECTIVE

To determine whether tauroursodeoxycholic acid (TUDCA) would prevent or ameliorate the liver injury in neonates treated with total parenteral nutrition (TPN).

STUDY DESIGN

Eligible infants were enrolled after surgery when serum direct bilirubin (DB) was <2 mg/dL. TUDCA (30 mg/kg/day) was given enterally to 22 subjects. A concurrent untreated/placebo group was evaluated for comparison (n = 30). Blood chemistries including alanine aminotransferase (ALT), alkaline phosphatase (AP), conjugated bilirubin (CB), and bile acids (BA) were obtained weekly.

RESULTS

There was no difference in peak serum CB, ALT, AP, or BA levels between the TUDCA-treated and control infants. When stratified for birth weight (<1500 g and >1500 g), no differences in peak CB, ALT, AP, or BA were noted. Serum CB levels were similar between TUDCA-treated and control infants after 14, 40, 60, 70, and 120 days of TPN.

CONCLUSION

TUDCA appears ineffective in preventing the development or treatment of TPN-associated cholestasis in neonates. Erratic biliary enrichment and prolonged inability to initiate treatment may compromise the utility of enterically administered TUDCA for TPN-treated infants.

Parenteral nutrition-associated liver complications in children

Parenteral nutrition is a life-saving therapy for patients with intestinal failure. It may be associated with transient elevations of liver enzyme concentrations, which return to normal after parenteral nutrition is discontinued. Prolonged parenteral nutrition is associated with complications affecting the hepatobiliary system, such as cholelithiasis, cholestasis, and steatosis. The most common of these is parenteral nutrition-associated cholestasis (PNAC), which may occur in children and may progress to liver failure. The pathophysiology of PNAC is poorly understood, and the etiology is multifactorial. Risk factors include prematurity, long duration of parenteral nutrition, sepsis, lack of bowel motility, and short bowel syndrome. Possible etiologies include excessive caloric administration, parenteral nutrition components, and nutritional deficiencies. Several measures can be undertaken to prevent PNAC, such as avoiding overfeeding, providing a balanced source of energy, weaning parenteral nutrition, starting enteral feeding, and avoiding sepsis.

Prevention of parenteral nutrition-associated liver disease in children

Liver injury is associated with parenteral nutrition therapy. Severity of injury varies from minimal and transient increases in liver-related blood tests to biliary cirrhosis and liver failure. Severe parenteral nutrition-related liver disease is usually confined to patients who have undergone massive intestinal resection. In these patients, early sepsis appears to cause initial liver injury, and recurring sepsis and inflammation, local or systemic, may result in its perpetuation and progression. Liver disease associated with parenteral nutrition is not necessarily related either to duration of parenteral nutrition or to delayed intestinal feeding. However, treatment includes enteral nutrition to promote enterohepatic circulation of bile acids and management of inflammation and sepsis, including control of intestinal bacterial overgrowth. Restriction of intravenous lipid emulsions may be important. The clinical picture of advanced liver failure related to short bowel syndrome differs from liver failure with an anatomically normal gastrointestinal tract. In the former, hyperbilirubinemia, hepatosplenomegaly, and functional hypersplenism dominate the clinical picture, and severe ascites and esophageal variceal hemorrhage are unusual. Early referral of these patients for intestinal and/or liver transplantation may provide the best chance for long-term survival.

Parenteral nutrition-associated cholestasis

Cholestasis is a major complication that occurs frequently in patients with the short bowel syndrome and accounts for the majority of morbidity and mortality in this group of patients. The exact cause of this condition is not known and the etiology is likely multifactorial. Many new mechanistic insights into this disease are discussed and have paved the way for future investigation. For now, prompt recognition, early initiation of enteral feeding, prevention of overfeeding with parenteral nutrition, and agents that induce bile flow may be useful to prevent this catastrophic morbidity.

New developments in total parenteral nutrition for children

The field of parenteral nutrition continues to evolve along two major paths: prevention of complications and refining of nutritional needs. Parenteral nutrition-associated liver disease remains a vexing problem. No single factor is to blame; rather, it requires a number of "hits." In the infant, the liver disease primarily appears to be related to prematurity of bile flow and production, infection, lack of enteral feedings, and most recently appreciated, perhaps free radicals. We are able to meet the nutritional needs of our patients, but our knowledge of actual nutritional requirements remains incomplete. Future studies need to define better appropriate intakes and to rigorously test the utility of proposed nutrients such as glutamine.