Outcomes of intestinal failure--a comparison between children with short bowel and dysmotile intestine

Long-term outcomes in newborn surgery

This article describes the common methods to study long-term outcomes in patients who have undergone major surgery in newborn period. It also sums up today's knowledge on the long-term outcome of some classic newborn surgical conditions. The analysis of long-term outcomes is important to pediatric surgeons. Knowledge of long-term outcome can guide the patient's management and principles of the follow-up throughout the patient's childhood. It also aims to give the parents of the patient a realistic picture on the development of their child. Recent data have shown that many patients who have undergone major surgery during early childhood have significant functional aberrations at adult age. Some of these have a profound influence on the quality of life of these patients.

Motility disorders in children with intestinal failure: a national tertiary referral center experience

PURPOSE

Intestinal dysmotility (ID) problems are common in patients with pediatric-onset intestinal failure (IF) and short bowel syndrome (SBS), leading to significant morbidity and delays in the advancement of enteral nutrition (EN). We aimed to investigate the clinical features and complications of ID in children with IF and SBS.

METHODS

Retrospective chart review of all children with IF and/or SBS who required parenteral nutrition (PN) > 6 weeks or small-intestinal resection ≥ 50%. Patients were divided into SBS and non-SBS groups. SBS group was divided into two subgroups: with and without ID. Patients with ID were identified (clinically, radiologically and functionally) and analyzed with regard to demographics, intestinal anatomy, complications and outcomes (short and long term).

RESULTS

A total of 42 children with IF were treated in our institution during 2003-2022. In non-SBS group (n = 10), ID was the most common cause of IF (80%). SBS-group included 32 children; 18 children (56%) developed ID. The clinical profile of SBS-ID patients (vs SBS) was: female gender (56%), remaining small bowel length ≤ 55 cm, estimated residual small bowel ≤ 28% (p = 0.045) and absence of ICV (56%). Common symptoms of the SBS-ID group were: food intolerance (61%), abdominal distension (50%), vomiting (44%), malabsorption and severe constipation. Complications included FTT (67%) (p = 0.003), bacterial overgrowth with subsequent bloodstream infection (33%) (p = 0.75), and lactic acidosis (11%). Lengthening procedure (STEP) was performed in 11 SBS-ID patients (61%) (p = 0.002). In all patients, STEP operation "rescued" their dysfunctional intestine. Eight of these patients (73%) were weaned from TPN. Survival rate was 100%; however, one SBS-ID patient is a candidate for combined intestinal and liver transplantation.

CONCLUSIONS

ID is the most common complication of SBS and is the most common cause of IF in non-SBS patients. ID has a high morbidity rate and various clinical manifestations. Successful treatment of these infants may be achieved with the use of tapering enteroplasty.

Neonatal Intestinal Failure Is Independently Associated With Impaired Cognitive Development Later in Childhood

OBJECTIVE

The impact of pediatric intestinal failure (IF) on neurodevelopment beyond infancy has not been systematically studied. Our aim was to evaluate cognitive and motor impairment and to identify risk factors for adverse outcomes among children with IF.

METHODS

We conducted a cross-sectional single-center study at the Helsinki University Children's Hospital. Patients with IF with >60 days of parental nutrition (PN) dependency aged between 3 and 16 years (n = 40) were invited to participate. The cognitive and motor skills were evaluated using validated tests: Wechsler Preschool and Primary Scale of Intelligence, 3rd edition, Wechsler Intelligence Scale for Children, 4th edition, and Movement Assessment Battery for Children, 2nd edition.

RESULTS

All the patients attending the study tests (n = 30, males = 24) were included. Their median age, gestational age, and birth weight was 7.5 (range 3-16) years, 35 (interquartile range [IQR] 28-38) weeks and 2238 (IQR 1040-3288) grams, respectively. Median duration of PN was 13 (IQR 5-37) months and 9 patients were currently on PN. Median intelligence quotient was 78 (IQR 65-91) and 10 (35%) patients had an intelligence quotient under 70 (-2 standard deviation). Significant motor impairment was detected in 10 patients (36%) and milder difficulties in 8 (28%). Adverse cognitive outcome was associated with neonatal short bowel syndrome, number of interventions under general anesthesia, and length of inpatient status, whereas adverse motor outcome was associated with prematurity.

CONCLUSION

Clinically significant cognitive and motor impairments are alarmingly common among neonatal patients with IF. We recommend early neurodevelopmental follow-up for all children with IF.

Generating an Artificial Intestine for the Treatment of Short Bowel Syndrome

Intestinal failure is defined as the inability to maintain fluid, nutrition, energy, and micronutrient balance that leads to the inability to gain or maintain weight, resulting in malnutrition and dehydration. Causes of intestinal failure include short bowel syndrome (ie, the physical loss of intestinal surface area and severe intestinal dysmotility). For patients with intestinal failure who fail to achieve enteral autonomy through intestinal rehabilitation programs, the current treatment options are expensive and associated with severe complications. Therefore, the need persists for next-generation therapies, including cell-based therapy, to increase intestinal regeneration, and development of the tissue-engineered small intestine.

Causes and prognosis of chronic intestinal pseudo-obstruction in 48 subjects: A 10-year retrospective case series

The aim of the study was to evaluate the prognosis and survival of pediatric subjects with chronic intestinal pseudo-obstruction (CIPO) and investigate the independent risk factors affecting their prognosis.This was a retrospective case series of all pediatric subjects suffering from CIPO and treated at the Pediatric Surgical ward of Xinhua Hospital between January 2006 and January 2016.The overall mortality was 19/48 (39.6%). Because of delayed CIPO diagnosis, many subjects underwent a variety of surgical procedures. The rate of additional surgical procedures was high (35/48, 72.9%), but the number of surgical procedures, parenteral nutrition, and megacystis did not affect mortality. Mycotic infection was significantly associated with mortality, while onset at <1 year and hypoganglionosis showed a tendency to be associated with mortality.Mycotic infection was associated with mortality of children with CIPO. Despite improving treatment approaches, the overall prognosis of CIPO remains poor. The choice of the surgical intervention could be based on standard criteria.

Health-related quality of life and neurodevelopmental outcomes among children with intestinal failure

Treatment results of pediatric intestinal failure have improved markedly during the last decades. With improved survival the attention is turning to other essential outcomes including quality of life and neurodevelopment. So far, relatively few studies with limited number of patients and variable methodology have addressed these issues. Based on these studies using generic health related quality of life tools, children with intestinal failure demonstrate decreased physical health, while PN-dependence is also associated with compromised emotional functioning. Impairments of social functioning are frequently observed among older children and parents. Few recent studies on neurodevelopment imply significant impairments in motor and mental skills among children with intestinal failure despite small sample sizes and limited follow-up times. Development of a disease-specific survey designed for the pediatric intestinal failure population could better reveal the health issues with greatest impact on quality of life. Robust studies with appropriate methodology on neurodevelopment in pediatric intestinal failure with extended follow-up times are urgently needed. Quality of life and neurodevelopment requires greater attention from medical professionals managing children with intestinal failure.

Paediatric Intestinal Pseudo-obstruction: Evidence and Consensus-based Recommendations From an ESPGHAN-Led Expert Group

OBJECTIVES

Chronic intestinal pseudo-obstructive (CIPO) conditions are considered the most severe disorders of gut motility. They continue to present significant challenges in clinical care despite considerable recent progress in our understanding of pathophysiology, resulting in unacceptable levels of morbidity and mortality. Major contributors to the disappointing lack of progress in paediatric CIPO include a dearth of clarity and uniformity across all aspects of clinical care from definition and diagnosis to management. In order to assist medical care providers in identifying, evaluating, and managing children with CIPO, experts in this condition within the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition as well as selected external experts, were charged with the task of developing a uniform document of evidence- and consensus-based recommendations.

METHODS

Ten clinically relevant questions addressing terminology, diagnostic, therapeutic, and prognostic topics were formulated. A systematic literature search was performed from inception to June 2017 using a number of established electronic databases as well as repositories. The approach of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) was applied to evaluate outcome measures for the research questions. Levels of evidence and quality of evidence were assessed using the classification system of the Oxford Centre for Evidence-Based Medicine (diagnosis) and the GRADE system (treatment). Each of the recommendations were discussed, finalized, and voted upon using the nominal voting technique to obtain consensus.

RESULTS

This evidence- and consensus-based position paper provides recommendations specifically for chronic intestinal pseudo-obstruction in infants and children. It proposes these be termed paediatric intestinal pseudo-obstructive (PIPO) disorders to distinguish them from adult onset CIPO. The manuscript provides guidance on the diagnosis, evaluation, and treatment of children with PIPO in an effort to standardise the quality of clinical care and improve short- and long-term outcomes. Key recommendations include the development of specific diagnostic criteria for PIPO, red flags to alert clinicians to the diagnosis and guidance on the use of available investigative modalities. The group advocates early collaboration with expert centres where structured diagnosis and management is guided by a multi-disciplinary team, and include targeted nutritional, medical, and surgical interventions as well as transition to adult services.

CONCLUSIONS

This document is intended to be used in daily practice from the time of first presentation and definitive diagnosis PIPO through to the complex management and treatment interventions such as intestinal transplantation. Significant challenges remain to be addressed through collaborative clinical and research interactions.

Enteral nutrition in pediatric intestinal failure: does initial feeding impact on intestinal adaptation?

Primary IF can be due to impaired gut length or impaired gut function; short bowel syndrome (SBS) is the leading cause of IF. In IF patients complete enteral starvation should be avoided whenever possible and enteral/oral nutrition (EN/ON) should be employed at the maximum tolerated amount in each phase of the clinical evolution of IF. Intraluminal nutrients have stimulatory effects on epithelial cells and on trophism that enhance intestinal adaptation. Areas covered: Evidence for nutritional interventions in pediatric IF is limited and of poor quality. Clinical practice in SBS feeding are more 'experience-based' rather than 'evidence-based' and this dearth of clinical evidence is partly due to the rarity of this condition. This review updates knowledge concerning the impact of the initial diet with EN/ON in neonatal onset SBS in the process of bowel adaption. Expert commentary: Human milk resulted the preferred starting diet and it is generally combined with amino-acids (AAs) in Northern America and with hydrolyzed proteins (HFs) in Europe; polymeric diet is rarely employed. HFs were not more effective than AAs in promoting intestinal adaptation.

Short bowel syndrome (SBS)-associated alterations within the gut-liver axis evolve early and persist long-term in the piglet model of short bowel syndrome

BACKGROUND AND AIM

Short bowel syndrome (SBS) is primarily characterized by malabsorption and malnutrition, resulting from loss of intestinal absorptive area following massive small bowel resection (SBR). Bile acids and the gut microbiota are functionally linked within the gut-liver axis; however, SBS-associated disturbances within the gut-liver axis remain largely unexplored. The aim of this study was to characterize the evolution of bile acid alterations within the gut-liver axis at both short-term and long-term time points and to relate these changes to alterations in colonic bacterial composition.

METHODS

Four-week-old piglets were assigned to 75% SBR, sham-operation or non-operation control groups. High throughput sequencing was employed to determine bacterial abundance in colonic content and ultra-performance liquid chromatography used to determine the bile acid concentration of gall bladder, portal serum, and fecal samples.

RESULTS

Bile acid complexity and relative abundance are altered in the SBS piglet model at two weeks post-SBR, and these changes persisted at six weeks post-SBR. Our examination of the microbial profile revealed an early and persistent loss in bacteria belonging to the Clostridiales order.

CONCLUSIONS

This study provides evidence of an early and persistent disturbance of the bile acid profile throughout the entero-hepatic circulation with an increase in the proportion of primary bile acids and a decrease in secondary bile acids following SBR. These changes were associated with a loss of bacteria belonging to the Clostridiales order consistent with a disturbance in the bile-microbial axis following SBR.

Surgical rehabilitation of short and dysmotile intestine in children and adults

AIMS

This is a descriptive study aiming to compare outcomes of intestinal rehabilitation surgery among pediatric and adult intestinal failure (IF) patients with either primary intestinal motility disorders or short bowel syndrome (SBS) treated by our nationwide program.

METHODS

Medical records of IF patients (n = 31, 71% children) having undergone autologous intestinal reconstructions (AIR) (n = 25), intestinal transplantation (ITx) (n = 5), or being listed for ITx (n = 2) between 1994 and 2014 were reviewed.

RESULTS

At surgery, median age was 3.4 (interquartile range, 1.0-22.1) in SBS (n = 22) and 16.5 (3.2-26.7) years in dysmotility patients (n = 9) who received median 60% and 83% of energy requirement parenterally, respectively. Median small bowel length was shorter in SBS than dysmotility patients (34 versus 157 cm, p < 0.001). Following AIR, none of the dysmotility patients achieved permanent intestinal autonomy, whereas 68% of SBS patients weaned off parenteral nutrition (PN) (p = 0.022) and none required listing for ITx. Five dysmotility patients who underwent ITx achieved intestinal autonomy. Regarding both AIR and ITx procedures, no significant difference in PN weaning was observed between the two subgroups. At last follow-up, 3.3 (0.6-8.0) years postoperatively, median plasma bilirubin was 6 (4-16) µmol/l, while liver biopsy showed fibrosis (Metavir stage 1-2) in 50% and cholestasis in 8%. Proportion of PN energy requirement had reduced significantly (p = 0.043) among PN-dependent SBS (n = 7) but not among dysmotility patients (n = 5). Overall survival was 90%.

CONCLUSION

AIR surgery was beneficial among selected SBS patients, whereas in intestinal dysmotility disorders, permanent PN weaning was only achieved by ITx.

Race affects outcome among infants with intestinal failure

OBJECTIVE

Intestinal failure (IF) is a rare, devastating condition associated with significant morbidity and mortality. We sought to determine whether ethnic and racial differences were associated with patient survival and likelihood of receiving an intestinal transplant in a contemporary cohort of children with IF.

METHODS

This was an analysis of a multicenter cohort study with data collected from chart review conducted by the Pediatric Intestinal Failure Consortium. Entry criteria included infants ≤ 12 months receiving parenteral nutrition (PN) for ≥ 60 continuous days and studied for at least 2 years. Outcomes included death and intestinal transplantation (ITx). Race and ethnicity were recorded as they were in the medical record. For purposes of statistical comparisons and regression modeling, categories of race were consolidated into "white" and "nonwhite" children.

RESULTS

Of 272 subjects enrolled, 204 white and 46 nonwhite children were available for analysis. The 48-month cumulative incidence probability of death without ITx was 0.40 for nonwhite and 0.16 for white children (P < 0.001); the cumulative incidence probability of ITx was 0.07 for nonwhite versus 0.31 for white children (P = 0.003). The associations between race and outcomes remained after accounting for low birth weight, diagnosis, and being seen at a transplant center.

CONCLUSIONS

Race is associated with death and receiving an ITx in a large cohort of children with IF. This study highlights the need to investigate reasons for this apparent racial disparity in outcome among children with IF.

Short bowel syndrome in infants: the critical role of luminal nutrients in a management program

Short bowel syndrome develops when the remnant mass of functioning enterocytes following massive resections cannot support growth or maintain fluid–electrolyte balance and requires parenteral nutrition. Resection itself stimulates the intestine’s inherent ability to adapt morphologically and functionally. The capacity to change is very much related to the high turnover rate of enterocytes and is mediated by several signals; these signals are mediated in large part by enteral nutrition. Early initiation of enteral feeding, close clinical monitoring, and ongoing assessment of intestinal adaptation are key to the prevention of irreversible intestinal failure. The length of the functional small bowel remnant is the most important variable affecting outcome. The major objective of intestinal rehabilitation programs is to achieve early oral nutritional autonomy while maintaining normal growth and nutrition status and minimizing total parenteral nutrition related comorbidities such as chronic progressive liver disease. Remarkable progress has been made in terms of survivability and quality of life, especially in the context of coordinated multidisciplinary programs, but much work remains to be done.

Serum FGF21 increases with hepatic fat accumulation in pediatric onset intestinal failure

BACKGROUND & AIMS

Previously, FGF21 has been related to glucose and lipid metabolism and liver steatosis. Our aim was to evaluate serum FGF21 levels in pediatric onset intestinal failure (IF).

METHODS

Serum FGF21 was measured in 35 IF patients at median age of 7.8 years (range 0.2-27) and 59 matched healthy controls. Thirty patients underwent liver biopsy.

RESULTS

Serum FGF21 levels were increased in patients compared to controls [229 pg/ml (21-20,345) vs. 133 pg/ml (7-1607), p=0.018]. Frequency of liver steatosis (60% vs. 50%, p=0.709) was similar during (6/10) and after (10/20) weaning off parenteral nutrition (PN). Patients with steatosis had markedly higher serum FGF21 concentration [626 pg/ml (21-20,345) vs. 108 pg/ml (32-568), p=0.002] and more advanced liver fibrosis [Metavir stage 1.6 (0-4) vs. 0.7 (0-3), p=0.020] without associated inflammation or Mallory body formation. Serum FGF21 levels reflected the degree of steatosis [FGF21 in grade 3 vs. grades 0-2, p<0.001; grade 1 vs. controls, p=0.002], and correlated with steatosis grade (r=0.589, p=0.001). Hepatic steatosis and serum FGF21 showed similar associations with duration of PN and remaining small bowel length (p<0.05 for all). In a multivariate regression model, liver steatosis grade (β=0.630, p=0.001) predicted serum FGF21 concentration.

CONCLUSIONS

In pediatric IF increased serum FGF21 levels reflect liver steatosis, while both are exclusively associated with duration of PN and extent of small intestinal resection. Liver steatosis is coupled with progression of fibrosis without accompanying inflammation. Serum FGF21 assay may be useful for diagnosing liver steatosis in IF patients.

Persistent abnormal liver fibrosis after weaning off parenteral nutrition in pediatric intestinal failure

The aim of this study was to evaluate the long-term effects of pediatric intestinal failure (IF) on liver histology. Altogether, 38 IF patients (median age: 7.2 years; range, 0.2-27) underwent liver biopsy, gastroscopy, abdominal ultrasound, and laboratory tests. Sixteen patients were on parenteral nutrition (PN) after 74 PN months (range, 2.5-204). Twenty-two had weaned off PN 8.8 years (range, 0.3-27) earlier, after 35 PN months (range, 0.7-250). Fifteen transplant donor livers served as controls. Abnormal liver histology was found in 94% of patients on PN and 77% of patients weaned off PN (P = 0.370). During PN, liver histology weighted with cholestasis (38% of patients on PN versus 0% of patients weaned off PN; P = 0.003) and portal inflammation (38% versus 9%; P = 0.050) were found. Fibrosis (88% versus 64%; P = 0.143; Metavir stage: 1.6 [range, 0-4] versus 1.1 [range, 0-2]; P = 0.089) and steatosis (50% versus 45%; P = 1.000) were equally common during and after weaning off PN. Plasma alanine aminotransferase (78 U/L [range, 19-204] versus 34 [range, 9-129]; P = 0.009) and conjugated bilirubin (43 μmol/L [range, 1-215] versus 4 [range, 1-23]; P = 0.037) were significantly higher during than after weaning off PN. Esophageal varices were encountered in 1 patient after weaning off PN. Metavir stage was associated with small bowel length (r = -0.486; P = 0.002) and number of septic episodes (r = 0.480; P = 0.002). In a multivariate analysis, age-adjusted small bowel length (ß = -0.533; P = 0.001), portal inflammation (ß = 0.291; P = 0.030), and absence of an ileocecal valve (ß = 0.267; P = 0.048) were predictive for fibrosis stage.

CONCLUSION

Despite resolution of cholestasis and portal inflammation, significant liver fibrosis and steatosis persist after weaning off PN. Extensive small intestinal resection was the major predictor for liver fibrosis stage.

Surgical treatment and outcomes of severe pediatric intestinal motility disorders requiring parenteral nutrition

AIM

The aim of this study was to characterize outcomes of children with severe intestinal motility disorders (IMD) requiring parenteral nutrition (PN).

METHODS

Twenty consecutive children with primary IMD requiring long-term PN between 1984 and 2010 were included. Median (interquartile range) follow-up was 13.1 (5.2-20.1) years. Treatment, PN dependence, growth, nutritional status, liver function, and survival were assessed.

RESULTS

Underlying etiology included chronic intestinal pseudo obstruction (CIPO; n=8) and Hirschsprung disease with extensive aganglionosis (n=12). CIPO and aganglionosis patients had 100 (86-100%) and 29 (19-40%) of age-adjusted small bowel length remaining, respectively. In order to facilitate enteral tolerance and avoid PN-associated liver disease, short aganglionic segment (40 cm) was left in situ in four of five cases, with aganglionosis extending to duodenojejunal flexure combined with Ziegler myectomy-myotomy in two. Six of seven children with aganglionosis extending into mid small intestine underwent staged jejunoanal pull-through. Feeding/venting gastrostomies (n=13) or jejunostomies were commonly employed. Probability of PN dependence owing to IMD was markedly increased in relation to short bowel syndrome (70 versus 19% at 5 years, P<0.0001). Two (10%) patients developed end-stage liver disease. A total of 11 (55%) patients (5 CIPO and 6 aganglionosis) weaned off PN after 8.2 years (1.8-17 years), including two patients after intestinal transplantation (ITx). Two children died before ITx-era giving overall survival of 90%. Survivors had well-preserved liver function, growth, and nutritional status.

CONCLUSIONS

Despite high PN dependence, long-term survival is achievable in the majority of children with IMD requiring PN. A wide repertory of surgical options including ITx is required for optimal outcomes.

Long-term controlled outcomes after autologous intestinal reconstruction surgery in treatment of severe short bowel syndrome

AIM

The aim of this study was to analyze outcomes of severe short bowel syndrome (SBS) treated with autologous intestinal reconstruction (AIR) surgery to facilitate independence of parenteral nutrition (PN).

METHODS

PN dependence, growth, nutritional status, liver function, and survival were comparatively assessed in SBS children treated with (n=10) or without (n=18) AIR surgery.

RESULTS

Median follow-up was 9.2 (4.9-14) years. Residual small intestinal length was 28 cm at birth. A total of 13 AIR procedures were performed at median age of 16 (11-41) months: serial transverse enteroplasty (STEP; n=8), longitudinal lengthening and tailoring (LILT; n=2), and tapering enteroplasty (n=3). Following STEP and LILT, length of the remaining small intestine increased by 19 (15-38) cm or 43% (38%-64%). Two children required repeat STEP due to recurrence of symptoms and bowel re-dilatation. Median duration of PN was 12 (11-17) months before and 14 (0-19) months after AIR. Eight children remain off PN 6.9 (3.6-9.7) years after surgery, and one with ultra short bowel (12 cm) receives 12% of energy as PN - all with reassuring growth and nutritional status and normal liver function. Actuarial PN dependence, including those who died on PN, was similar (P=0.19) with or without AIR surgery being 30% and 20% at four years, respectively. Complications of AIR surgery (lymphocele, bowel obstruction, and staple line bleeding) resolved without operative interventions. Survival was 90% with and 83% without AIR procedures.

CONCLUSIONS

AIR surgery can provide long-term survival, independence of PN, and satisfactory general health in selected children with severe SBS.

Long-term outcomes of Hirschsprung's disease

Despite significant developments in the understanding of the pathologic anatomy and physiology of Hirschsprung's disease (HD), the results of surgical therapy remain far from perfect. The functional defects and psychosocial difficulties that occur commonly in children with HD are passed on to adulthood in a significant proportion of patients. Recent prospective and adequately controlled cross-sectional studies reveal that constipation and fecal soiling are common late sequelae in adulthood. HD patients show uniformly lower scores of overall bowel function than healthy control subjects. Functional outcome and quality of life may be interrelated and deteriorate with increasing age. Despite these shortcomings, at adult age, most of the HD patients appear to be able to function as normal members of the society in terms of psychosocial, occupational, and recreational activities. Patients are at risk of developing related conditions, such as cancer, that require planning of specific screening programs. Many of the long-term problems that these patients experience are specific to HD. The follow-up of HD patients should be performed by medical personnel familiar with the disease, preferably in a specialized referral center, and the follow-up should continue beyond childhood.

Medical update and potential advances in the treatment of pediatric intestinal failure

Short bowel syndrome (SBS) and intestinal failure are chronic malabsorption disorders with considerable nutritional and growth consequences in children. Intestinal failure occurs when the functional gastrointestinal mass is reduced even if there is normal anatomical gastrointestinal length. A number of management strategies are often utilized to achieve successful intestinal rehabilitation and maintain adequate nutrition to avoid intestinal transplant. These strategies include minimizing the effect of parenteral associated liver disease, limiting catheter complications, and treating bacterial overgrowth in the remaining small intestine. In addition, there continues to be significant research interest in enhancing intestinal adaptation with targeted therapies. The purpose of this review is to discuss current perspectives and to highlight recent medical advances in novel investigational therapies.

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

BACKGROUND AND OBJECTIVE

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Preventing parenteral nutrition liver disease

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

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

BACKGROUND

Small intestine essentially regulates cholesterol homeostasis.

AIMS

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

METHODS

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

RESULTS

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

CONCLUSION

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