Neonatal short bowel syndrome

Nutrition and immunological status in long-term follow up of children with short bowel syndrome

BACKGROUND

Little is known about the long-term evolution, nutrition status, growth, and eventual deficiencies of patients with short bowel syndrome (SBS) adapted to oral feeding after parenteral nutrition (PN). Because there are not absolute criteria for weaning from parenteral or enteral nutrition to oral feeding, new nutrient deficiencies may develop. Subtle nutrition deficits could induce subclinical immune deficiencies; therefore, we studied long-term growth, nutrition status, and the state of the immune system in 10 patients with SBS after weaning PN for at least 2 years.

METHODS

Ten children with SBS (3-12 years old; mean, 7.4 years) who had not received PN for at least 2 years were studied. Anthropometric measurements, hemoglobin values, and indicators of iron, zinc, copper, folate and vitamin B(12) nutrition status were evaluated, along with immunoglobulins, lymphocyte subpopulations, and polymorphonuclear candidicidal activity.

RESULTS

Weight-for-height was normal in 8 children; height-for-age was low in 5 children whose SBS was established early in life. Fat body mass was also low in 5 subjects. Four children presented macrocytosis, 2 with anemia. Low serum levels of vitamin B(12) (1 child), folates (4 children), and ferritin (2 children) were observed. Diminished candidicidal activity (4 children) was the only remarkable immunological abnormality.

CONCLUSION

Many biologic and growth deficiencies are frequently seen in patients with SBS, even in children adapted to enteral feeding. This finding and the existence of previously unreported decreased candidicidal activity in some patients with SBS deserve long-term clinical and biologic follow up.

Epidermal growth factor and bombesin act synergistically to support intestinal adaptation in rats with massive small bowel resection

Intestinal adaptation is the most important event in short bowel syndrome following a massive small bowel resection. Effects of various growth factors and their synergism have been well documented in intestinal adaptation. This study aimed to compare the effect of two different trophic agents, epidermal growth factor (EGF) and bombesin (BBS), on intestinal adaptation following massive intestinal resection. Sprague-Dawley male rats were assigned to one of four groups after a 75% small bowel resection. Either EGF (90 microg/kg), BBS (10 microg/kg), EGF+BBS, or bovine serum albumin (BSA) were injected subcutaneously three times a day. The animals were killed 10 days after the operation. Weight loss and morphologic parameters such as mucosal thickness, villus height, crypt depth, villus-to-crypt ratio, and muscularis propria height were measured. In the EGF+BBS group, mucosal thickness was found to be significantly increased compared with the other study groups (p<0.05). Similarly, villus height was significantly increased only in the EGF+BBS group (p<0.05). In the BBS group, both villus height and mucosal thickness showed a slight increase, but the values were not statistically significant compared with the vehicle-treated group. There were no significant differences in any of the remaining parameters between the groups. The results of this study indicate that the gut hormones EGF and BBS act synergistically in facilitating the adaptive response of the remnant ileum to massive intestinal resection.

Neonatal short bowel syndrome: a cohort study

BACKGROUND

To date, our knowledge of morbidity and mortality in neonatal short bowel syndrome (SBS) is based on individual case series. Shortcomings of the published literature include long patient recruitment time, selection bias, variable SBS definitions, failure to account for gestational age, and incomplete follow-up. By applying more rigorous methodology, our aim was to determine outcomes of SBS neonates compared with a control group of neonates without SBS.

METHODS

A cohort study of all neonates with abdominal pathology requiring laparotomy between January 1, 1997, and December 31, 1998, with observation through July 1, 2001. Short bowel syndrome was defined as patients requiring parenteral nutrition for more than 42 days or residual small bowel length of less than 25% predicted by gestational age. Student's t test, Mann-Whitney U test, and chi2 were used where appropriate. Kaplan-Meier curves were used to determine cumulative survival. Covariates important in the development of SBS were examined using forward step-wise logistic regression.

RESULTS

There were 175 patients (with SBS = 40, without SBS = 135) with a mean gestational age of 30.7 +/- 4.6 weeks vs 35.9 +/- 4.8 weeks, respectively (P < .0005). The patients with SBS suffered significantly more morbidity than the group without SBS in all categories of investigation (surgical complications, septic events, central venous line complications, duration to adaptation and parenteral nutrition independence, cholestasis and liver failure, and duration of hospitalization). The case fatality rate was 37.5% in patients with SBS vs 13.3% in patients without SBS (P = .001). Most of the deaths were caused by liver failure or sepsis and occurred within 1 year from the date of surgery. Presence of an ileostomy (exp(B) = 12.29; P < .0005) and a residual small bowel length less than 50% of the original length (exp(B) = 26.84; P < .0005) were the only 2 variables in a logistic regression analysis found to be independently associated with the development of SBS.

CONCLUSION

This cohort study clearly illustrates the tremendous morbidity experienced by infants with SBS relative to other surgical neonates. Accurate estimates of the morbidity associated with SBS enables clinicians to appropriately counsel parents, allocate resources and initiate therapeutic trials.

Long-term parenteral nutritional support and intestinal adaptation in children with short bowel syndrome: a 25-year experience

OBJECTIVE

To analyze the outcome of children with short bowel syndrome (SBS) who required long-term parenteral nutrition (PN).

STUDY DESIGN

Retrospective analysis of children (n=78) with SBS who required PN >3 months from 1975 to 2000.

STATISTICS

univariate analysis, Kaplan-Meier method, and Cox proportional regression model were used.

RESULTS

We identified 78 patients. Survival was better with small bowel length (SBL) >38 cm, intact ileocecal valve (ICV), intact colon, takedown surgery after ostomy (all P <.01), and primary anastomosis (P <.001). PN-associated early persistent cholestatic jaundice (P <.001) and SBL of <15 cm (P <.01) were associated with a higher mortality. Intestinal adaptation was less likely if SBL <15 cm (P <.05), ICV was removed, colonic resection was done (both P <.001), >50% of colon was resected (P <.05), and primary anastomosis could not be accomplished (P <.01). Survival was 73% (57), and 77% (44) of survivors had intestinal adaptation.

CONCLUSIONS

SBL, intact ICV, intestinal continuity, and preservation of the colon are important factors for survival and adaptation. Adaptation usually occurred within the first 3 years. Need for long-term PN does not preclude achieving productive adulthood. Patients with ICV even with <15 cm of SBL and patients with SBL >15 cm without ICV have a chance of intestinal adaptation.

Enterocyte metabolism during early adaptation after extensive intestinal resection in a rat model

OBJECTIVE

A better knowledge of intestinal adaptation after resection is required to improve the nutritional support that is given to patients. The aim of this study was to understand the metabolic changes underlying early adaptation after massive intestinal resection.

METHODS

Rats were assigned to either 80% intestinal resection or transection. All animals received the same intragastric nutrition. On day 8, plasma glutamine turnover was measured. Substrate use was determined on isolated enterocytes that were incubated in the presence of D-[U-(14)C] glucose (2 mmol/L), L-[U-(14)C] glutamine (2 mmol/L), L-[U-(14)C] arginine (1 mmol/L), or L-[1-(14)C] ornithine (1 mmol/L).

RESULTS

Plasma glutamine turnover was similar in both groups. The rate of enterocyte glutamine use was significantly increased in the resection group, although the maximal glutaminase activity was unchanged. Glutathione generation was enhanced 3-fold in remnant intestine as compared with transected intestine (P <.05). L-ornithine decarboxylation was increased markedly in resected animals (P <.05), without any detectable change of maximal ornithine decarboxylase activity.

CONCLUSION

The early phase of intestinal adaptation after resection induces changes in enterocyte glutamine and ornithine metabolism that may be related, in part, to increased de novo polyamine synthesis. This observation suggests that a supplementation of artificial nutrition by nutrients that lead to the generation of trophic agents may be of potential interest.

Irreversible intestinal failure

Intestinal failure (IF) can be defined as the reduction of functional gut mass below the minimal amount necessary for digestion and absorption adequate to satisfy the nutrient and fluid requirements for maintenance in adults or growth in children. In developed countries, IF mainly includes individuals with the congenital or early onset of conditions requiring protracted or indefinite parenteral nutrition (PN). Short bowel syndrome was the first commonly recognized cause of protracted IF. The normal physiologic process of intestinal adaptation after extensive resection usually allows for recovery of sufficient intestinal function within weeks to months. During this time, patients can be sustained on parenteral nutrition. Only a few children have permanent intestinal insufficiency and life-long dependency on PN. Non-transplant surgery including small bowel tapering and lengthening may allow weaning from PN in some cases. Hormonal therapy with recombinant human growth hormone has produced poor results while therapy with glucagon-like peptide-2 holds promise. Congenital diseases of enterocyte development such as microvillus inclusion disease or intestinal epithelial dysplasia cause permanent IF for which no curative medical treatment is currently available. Severe and extensive motility disorders such as total or subtotal intestinal aganglionosis (long segment Hirschsprung disease) or chronic intestinal pseudo-obstruction syndrome may also cause permanent IF. PN and home-PN remain are the mainstays of therapy regardless of the cause of IF. Some patients develop complications while receiving long-term PN for IF especially catheter related complications (thrombosis, sepsis) and liver disease. These patients may be candidates for intestinal transplantation. This review discusses the causes of irreversible IF and emphasizes the specific medico-surgical strategies for prevention and treatment of these conditions at several stages of IF.

Surgical approaches and intestinal transplantation

The surgical treatment of short-bowel syndrome has been traditionally based on the correction of mechanical obstruction, which is responsible for bacterial overgrowth syndrome, or on intestinal expansion procedures. Since the introduction of clinical intestinal transplantation by Lillehei in 1964, there have been remarkable advances in the immunosuppressive regimens to control rejection and in preservation techniques, monitoring and critical care. Newer and more powerful immunosuppressants have helped to transform intestinal transplantation into a clinical reality-transplantation can now be a life-saving procedure for patients with intestinal failure. It is currently indicated in the event of life-threatening complications of an underlying disease or from total parenteral nutrition (TPN). Rehabilitation in successful cases is excellent.

Classification, epidemiology and aetiology

Intestinal failure and its most important cause, short-bowel syndrome (SBS), are rare clinical entities leading to a vast complex of symptoms and complications with significant morbidity and mortality. Both conditions occur as the result of a massive reduction in enteral nutrient absorptive capacity. Disease manifestation is based on aetiological and anatomical characteristics such as remaining intestinal length and the presence of a functionally intact colon. Congenital and perinatal conditions, for example, intestinal atresia, necrotizing enterocolitis (NEC) and intestinal volvulus are the most important causes in children. The aetiology in adults is based on diseases inducing loss of intestinal function or loss of intestinal surface area after extensive surgical resections. The most frequent causes are mesenteric infarction, radiation enteritis and Crohn's disease. Knowledge of the epidemiology of intestinal failure and SBS is limited, being mainly based on the extrapolated figures of home parenteral nutrition centres and single-centre studies. At present, the incidence of SBS is estimated to be 2-5 per million.

Mortality and economics in short bowel syndrome

The incidence of patients with short-bowel syndrome (SBS) has increased over the years due to progress of intensive care medicine and parenteral nutrition techniques. These techniques have significantly improved the prognosis of neonates, children and adults who have lost major parts of their intestinal tract. Long-term survival is possible and does not depend primarily on the length of the remaining bowel but on complications such as parenteral nutrition-associated cholestasis, recurrent septicaemia, central venous catheter infections, and the motility of the remaining intestine. Thus, the overall related mortality in infants with SBS ranges from 15 to 25%, and in adults from 15 to 47%, depending on the age of the patients, the underlying disease, and the duration on total parenteral nutrition. Home parenteral nutrition (HPN) significantly decreases the complication rate and improves the psychological situation of the patient. Additionally, HPN reduces in-hospital cost significantly. Nevertheless, the annual costs/patient are between $100000 and $150000. The mortality rate of SBS patients on HPN is about 30% after 5 years, which is still lower than the 5-year survival rate of intestinal grafts, and it is about equal to patients' survival after intestinal transplantation. However, the overall costs of a successful intestinal transplantation are already lower after 2 years when compared with the cost of a prolonged HPN programme.

Current status of small bowel transplantation in children: update 2003

This article reviews the current indications for intestinal transplantation and advances in immunosuppression and postoperative care, which help to improve the outcome results of intestinal transplantation. Major current controversies and future trends are discussed briefly.

Glucagon-Like Peptide-2 and Short-Chain Fatty Acids: A New Twist to an Old Story

The nutritional regulation of intestinal adaptation extends beyond the route of nutrient administration as specific nutrients are known to mediate the adaptive response. Dietary carbohydrates are known to enhance intestinal adaptation in patients with short-bowel syndrome. This review discusses SCFA-induced adaptation in intestinal structure and function in adult rat and neonatal piglet models. Potential mechanisms relate to the salvage of energy as SCFA in the colon, direct mediation of intestinal adaptation by SCFA and stimulated release of glucagon-like peptide-2 (GLP-2) from enteroendocrine L cells by SCFA. Among the produced SCFA, butyrate appears to be responsible for increasing plasma GLP-2 concentration, in addition to the enterotrophic effects. Emerging evidence reveals that physiological concentrations of butyrate acutely upregulate the expression of key enterocyte-associated nutrient transporters. Focused experiments are needed to carefully identify the critical components of intestinal adaptation and yield conclusions regarding the relative contributions of SCFA and GLP-2 during the various phases of this process.

Intestinal transplantation

Advances in immunosuppressive treatment as well as better monitoring and control of acute rejection have brought intestinal transplantation (ITx) into the realm of standard treatment for permanent intestinal failure. The results from the intestinal Transplant International Registry (www.intestinaltransplant.org) indicate that ITx is currently an acceptable clinical modality for selected patients with permanent intestinal failure. The goal of this short review is to deal with indications, clinical results and complications of ITx. Although it has been used in humans for the past two decades, very few data are available regarding graft function and its monitoring.

Outcome and quality of life in paediatric home parenteral nutrition

In this review the current status of home parenteral nutrition is analysed, with respect to the predictability of weaning from nutritional support and the risk of developing major complications associated with the technique, the loss of vascular access and liver disease. These two complications were evaluated because they represent the more important indication for intestinal transplantation, the availability of which has changed the perspectives of patients and of physicians. Analysis of outcomes from the largest series allows the identification of patients who could be weaned from parenteral nutrition. Important prognostic factors in patients affected by short bowel syndrome are the length and type of the remnant and the time to tolerate enteral feeding. The main complications of therapy are sepsis, thrombosis, nutrient imbalances and liver disease. Sepsis and thrombosis could lead to line replacement and the loss of vascular access. Sepsis no longer represents a major cause of death, but it is a frequent complication. In some patients, it is difficult to assess the risk factors for sepsis, which is possibly related to a poorer outcome. The care of gut failure appears to be the best preventative measure for the occurrence of cholestatic liver disease, but further studies are needed to define the eventual role of lipid emulsion and of specific nutrient deficiency. The quality of life still remains to be studied: because home parenteral nutrition in children has a longer duration, its analysis is mandatory.

Update on management and treatment of short gut

Management of patients with short-bowel syndrome represents a formidable challenge. Aggressive treatment including nutritional care and anticipation of potential complications and rapid treatment of complications enhance outcome. New therapies offer the promise of significantly improving morbidity and mortality. Intestinal transplant is appropriate for infants who would otherwise die from liver disease, recurrent sepsis, or lack of venous access.

Nutritional and other postoperative management of neonates with short bowel syndrome correlates with clinical outcomes

OBJECTIVE

To determine correlates of clinical outcomes in patients with short bowel syndrome (SBS).

METHODS

Retrospective medical record review of neonates treated between 1986 and 1998 who met our criteria for SBS: dependence on parenteral nutrition (PN) for at least 90 days after surgical therapy for congenital or acquired intestinal diseases.

RESULTS

Thirty subjects with complete data were identified; 13 (43%) had necrotizing enterocolitis, and 17 (57%)had intestinal malformations. Mean (SD) residual small bowel length was 83 (67) cm. Enteral feeding with breastmilk (r = -0.821) or an amino acid-based formula (r = -0.793) was associated with a shorter duration of PN, as were longer residual small bowel length (r = -0.475) and percentage of calories received enterally at 6 weeks after surgery(r = -0.527). Shorter time without diverting ileostomy or colostomy (r = 0.400), enteral feeding with a protein hydrolysate formula (r = -0.476), and percentage of calories received enterally at 6 weeks after surgery (r = -0.504) were associated with a lower peak direct bilirubin concentration. Presence of an intact ileocecal valve and frequency of catheter-related infections were not significantly correlated with duration of PN. In multivariate analysis, only residual small bowel length was a significant independent predictor of duration of PN, and only less time with a diverting ostomy was an independent predictor of peak direct bilirubin concentration.

CONCLUSIONS

Although residual small bowel length remains an important predictor of duration of PN use in infants with SBS, other factors, such as use of breast milk or amino acid-based formula, may also play a role in intestinal adaptation. In addition, prompt restoration of intestinal continuity is associated with lowered risk of cholestatic liver disease. Early enteral feeding after surgery is associated both with reduced duration of PN and less cholestasis.

Extremely short small bowel induces focal tubulointerstitial fibrosis

BACKGROUND

Arginine becomes an essential amino acid after massive resection of the small bowel as a result of decreased biosynthesis of citrulline in the remaining small bowel. It is also reported that nitric oxide (NO) is synthesized from l-arginine by NO synthase (NOS), and NO is involved in the regulation of blood flow in the kidney. The authors observed a patient with an extremely short small bowel, showing focal tubulointerstitial fibrosis. The experiment was designed to clarify whether massive small bowel resection (SBR) produces focal tubulointerstitial fibrosis in the kidney.

METHODS

An experimental study was performed using 4-week-old rats with 90% proximal SBR either with or without arginine supplementation for 6 weeks after surgery.

RESULTS

In rats without arginine supplementation, low plasma levels of citrulline and arginine increased urinary excretion of orotate, and focal tubulointerstitial fibrosis was observed 6 weeks after 90% SBR. The data from plasma amino acid chromatography and increased excretion of urinary orotate suggested the presence of arginine deficiency. The kidney pathology was similar to that of our patient. Rats with arginine supplementation after 90% SBR and pair-fed control rats without 90% SBR showed almost normal glomeruli and tubulointerstitium.

CONCLUSIONS

Experimental study strongly suggests that arginine deficiency causes focal tubulointerstitial fibrosis in the kidney after massive SBR.

Short bowel syndrome in infants and children: an overview

Short bowel syndrome is a spectrum of malnutrition resulting from inadequate bowel length. In infant and pediatric patients, the most common causes are necrotizing enterocolitis, abdominal wall defects, jejunal ileal atresia, and mid gut volvulus. There appear to be regional variations in etiology. Since the publication of Wilmore's classic monograph in 1972, there have been significant improvements in monitoring and nutritional support. In the modern era, survival rate ranges from 80% to 94%, and the presence or absence the ileal cecal valve appears to not impact on mortality rate, but does significantly affect the length of time on total parenteral nutrition TPN. The most common morbidities remain sepsis, both central line related and bacterial overgrowth, and TPN cholestasis. Long-term recovery of these children often is remarkably normal, but there is a 10% to 15% incidence of neurologic and developmental defects. The clinical and ethical considerations around the care of infants with 20 to 40 cm of residual bowel remains controversial, as does the place of intestinal transplantation, especially in patients developing gut failure in infancy. Perioperative surgical decision making plays a critical role in the long-term outcome of these patients. This chapter presents an overview of the current status of care and outcome in this difficult population; these topics are further expanded in subsequent chapters.

Indications for pediatric intestinal transplantation: a position paper of the American Society of Transplantation

Parenteral nutrition represents standard therapy for children with short bowel syndrome and other causes of intestinal failure. Most infants with short bowel syndrome eventually wean from parenteral nutrition, and most of those who do not wean tolerate parenteral nutrition for protracted periods. However, a subset of children with intestinal failure remaining dependent on parenteral nutrition will develop life-threatening complications arising from therapy. Intestinal transplantation (Tx) can now be recommended for this select group. Life-threatening complications warranting consideration of intestinal Tx include parenteral nutrition-associated liver disease, recurrent sepsis, and threatened loss of central venous access. Because a critical shortage of donor organs exists, waiting times for intestinal Tx are prolonged. Therefore, it is essential that children with life-threatening complications of intestinal failure and parenteral nutrition therapy be identified comparatively early, i.e. in time to receive suitable donor organs before they become critically ill. Children with liver dysfunction should be considered for isolated intestinal Tx before irreversible, advanced bridging fibrosis or cirrhosis supervenes, for which a combined liver and intestinal transplant is necessary. Irreversible liver disease is suggested by hyperbilirubinemia persisting beyond 3-4 months of age combined with features of portal hypertension such as splenomegaly, thrombocytopenia, or prominent superficial abdominal veins; esophageal varices, ascites, and impaired synthetic function are not always present. Death resulting from complications of liver failure is especially common during the wait for a combined liver and intestinal transplant, and survival following combined liver and intestinal Tx is probably lower than following an isolated intestinal transplant. The incidence of morbidity and mortality following intestinal Tx is greater than that following liver or kidney Tx, but long-term survival following intestinal Tx is now at least 50-60%. It is probable that outcomes shall improve in the future with continued refinements in operative technique and post-operative management, including immunosuppression.

[Home artificial nutrition in children. Indications and organization]

Home enteral and parenteral nutritions are logical alternatives to long-term hospitalization when a long-term nutritional support is required. They are effective and safe methods, compatible with a good quality of life. Major cost savings have been demonstrated as a result of home nutrition rather than hospitalization. Nevertheless, one must not underestimate the importance of the families' teaching and the medical follow-up to prevent somatic and psychological complications. The quality of home nutrition programmes depends on the organization of the nutrition support teams based on close collaboration between the various involved professionals.

Central venous catheter-related infections in children on long-term home parenteral nutrition: incidence and risk factors

BACKGROUND AND AIMS

This study aimed to assess the incidence and etiology of central venous catheter (CVC) infections in children on home parenteral nutrition (HPN).

METHODS

207 CVC-years were studied retrospectively in 47 children on HPN, aged 8.1+/-5.0 years.

RESULTS

125 CVC were used (means: 2.6 CVC/patient and 21 months utilization/CVC). Half of the hospitalizations (162) were due to proven CVC-related infections. The mean infection incidence was 2. 1/1000 HPN days. The total population divided in two groups below and above this value: group one including 24 children, incidence < or = 2.1 per 1000 days (mean: 0.83) and group two including 23 children, incidence >2.1 per 1000 days (mean: 4.3). No differences were found between the two groups in terms of underlying disease, presence of ostomies, age at the time of HPN onset, or micro-organisms responsible. The only differences (p<0.05) were the mean duration of HPN (longer in group one) and the delay between HPN onset and the first infection (longer in group one).

CONCLUSIONS

This study does not highlight any risk factors for CVC infection. However, early CVC infections after HPN onset appear to predict a bad prognosis.

Intestinal transplantation: indications, results and strategy

The term 'intestinal failure' is now often used to describe gastrointestinal function insufficient to satisfy body nutrient and fluid requirements. The first recognized condition of intestinal failure was short bowel syndrome. Severe motility disorders such as chronic intestinal pseudo-obstruction syndrome in children as well as congenital intractable intestinal mucosa disorders are also forms of intestinal failure, because no curative treatment for these diseases is yet available. Parenteral nutrition and home parenteral nutrition remain the mainstay of therapy for intestinal failure, whether it is partial or total, provisional or permanent. However, some patients develop complications while receiving standard therapy for intestinal failure and are considered for intestinal transplantation. Indeed, recent advances in immunosuppressive treatment and the better monitoring and control of acute rejection have brought intestinal transplantation into the realm of standard treatment for intestinal failure. Although it has been used in humans for the past two decades, this procedure has had a slow learning curve. According to the current results, this challenging procedure may be performed in children or adults, only under certain conditions.

Long-term survival and parenteral nutrition dependence in adult patients with the short bowel syndrome

BACKGROUND & AIMS

The short bowel syndrome (SBS) may be associated with either transient or permanent intestinal failure, presently treated by parenteral nutrition (PN). Survival and PN-dependence probabilities, taking into account both small bowel remnant length and the type of the digestive circuit of anastomosis, are not known in adult SBS patients. The aim of this study was to assess such prognostic factors.

METHODS

A total of 124 consecutive adults with nonmalignant SBS were enrolled from 1980 to 1992 at 2 home PN centers. They were analyzed for survival and PN-dependence probabilities using the Cox model and for PN dependence using linear discriminant analysis. Data were updated in April 1996.

RESULTS

Survival and PN-dependence probabilities were 86% and 49% and 75% and 45% at 2 and 5 years, respectively. In multivariate analysis, survival was related negatively to end-enterostomy, to small bowel length of <50 cm, and to arterial infarction as a cause of SBS, but not to PN dependence. The latter was related negatively to postduodenal small bowel lengths of <50 and 50-99 cm and to absence of terminal ileum and/or colon in continuity. Cutoff values of small bowel lengths separating transient and permanent intestinal failure were 100, 65, and 30 cm in end-enterostomy, jejunocolic, and jejunoileocolic type of anastomosis, respectively.

CONCLUSIONS

In adult SBS patients, small bowel length of <100 cm is highly predictive of permanent intestinal failure. Presence of terminal ileum and/or colon in continuity enhances both weaning off PN and survival probabilities. After 2 years of PN, probability of permanent intestinal failure is 94%. These rates may lead to selection of other treatments, especially intestinal transplantation, instead of PN, for permanent intestinal failure caused by SBS.

Intestinal absorption and permeability in paediatric short-bowel syndrome: a pilot study

BACKGROUND

Sugar absorption tests are an effective, noninvasive way to assess intestinal permeability. The role of intestinal barrier integrity in complications and outcome of short-bowel syndrome is not known. The purpose of the study was to evaluate whether such tests provide information on the status of intestinal mucosa of these patients.

METHODS

Six children with short-bowel syndrome--median age, 12 months, and median small bowel length at birth, 30 cm--had a sugar test with 3-o-methyl-D-glucose, D-xylose, D-rhamnose, and melibiose approximately 2 months after operation. The melibiose/L-rhamnose ratio was used as an index of permeability, and percentages of 3-o-methyl-D-glucose and D-xylose absorbed were used as indices of absorption. Parenteral nutrition requirement, bowel length, liver disease, recent sepsis, and bacterial overgrowth were recorded.

RESULTS

Three patients had increased permeability, and all of them had had a recent episode of sepsis and severe liver disease. All subjects had malabsorption of 3-o-methyl-D-glucose, and five of six had malabsorption of D-xylose and L-rhamnose. The absorption of 3-o-methyl-D-glucose correlated with bowel length (r2 = 0.78; P = 0.04), whereas the absorption of D-xylose correlated with parenteral requirement (r2 = 0.66; P = 0.04) at that time.

CONCLUSIONS

Increased permeability was observed in three of six patients with short-bowel syndrome associated with a recent episode of sepsis and severe liver disease. Other indices of malabsorption correlated significantly with different clinical features of the disease. A prospective larger scale study in a homogeneous population is indicated to assess at multiple points during the disease course whether the test can be helpful in the management of these patients.

Intestinal transplantation

Intestinal transplantation might become the alternative to definitive parenteral nutrition in patients with permanent intestinal failure. Indeed, recent advances in immunosuppressive treatment and better monitoring and control of acute rejection have brought intestinal transplantation into the realms of standard treatment of intestinal failure. This procedure may be performed in adult or paediatric patients under certain conditions. This short review focuses on the current clinical results and indications for intestinal transplantation and discusses the strategy regarding this challenging procedure.

Short bowel syndrome

Short bowel syndrome has significant morbidity and is potentially lethal especially when intestinal loss is extensive. The pathophysiology of short bowel syndrome, its aetiology, prognosis and our understanding of the mechanisms of adaptation are reviewed. Management by a multi-disciplinary nutritional care team is advocated and should be directed to the maintenance of growth and development, the promotion of intestinal adaptation, the prevention of complications and the establishment of enteral nutrition. The choice of enteral feed, the role of drugs and the use of pro-adaptive nutrients and agents are discussed. Complications including cholestasis and catheter related sepsis are outlined with strategies to reduce them. Finally the roles of secondary surgical interventions including transplantation are discussed.

Home enteral and parenteral nutrition in children

The prevalence of home enteral and parenteral nutrition programmes is rising rapidly all over the world, in children as in adults. Home artificial nutrition, especially parenteral nutrition, is an expensive technology but is life-saving for many patients. The only possible alternative to home treatment is keeping patients in hospital, and cost-benefit studies have demonstrated that home nutrition is about 70% more cost-effective than hospital-based therapy. Although home nutrition is usually considered by children and families to lead to an improvement in their quality of life, the complications of these techniques, including psychological consequences, have to be carefully assessed and prevented.

Enteral ornithine alpha-ketoglutarate enhances intestinal adaptation to massive resection in rats

Ornithine alpha-ketoglutarate (OKG) has been advocated in the treatment of critically ill patients for its anabolic effect on protein metabolism. Since OKG is a precursor of glutamine, arginine, and polyamines, key substrates of intestinal metabolism and function, we investigated the influence of OKG on intestinal adaptation and trophicity and on glutamine status after small bowel resection. After massive (80%) small bowel resection, rats were enterally fed for 7 days with a standard diet supplemented with either OKG (2 g/kg/d) or an isonitrogenous amount of glycine. OKG induced an adaptative hyperplasia of the villi, demonstrated in the jejunum by an increase in the villus height to crypt depth ratio (OKG v control, 4.3+/-0.4 v 3.3+/-0.5, P < .01) along with an increase (P < .05) in ornithine decarboxylase (ODC) activity (+80%) and ornithine content (+102%). Plasma glutamine (+25%) and muscle glutamine (anterior tibialis [AT], +43%; extensor digitorum longus [EDL], +54%) and protein (AT, +32%) were significantly higher (P < .05) after OKG administration, supporting its role in the restoration of glutamine pools. In summary, enterally administered OKG, which enhances intestinal adaptation after massive resection and improves muscle glutamine and protein content, could contribute significantly to nutritional management after small bowel resection.

Short bowel syndrome in pediatric patients

The treatment of infants and children with short bowel syndrome aims at restoring the intestinal continuity and at improving the physiological process of gut adaptation. Mucosal hyperplasia allows the remaining gut to ensure an adequate digestion and an absorption process leading to intestinal autonomy. During the period of adaptation, appropriate parenteral and/or enteral feeding must be directed at maintaining an optimal nutritional status. Delay of intestinal autonomy depends on the characteristics of the residual intestine: length, presence of the ileocecal valve and colon, and motor function. Bacterial overgrowth compromises intestinal adaptation and increases the risk of liver disorders. Few patients will remain long-term dependent on parenteral nutrition. All approaches aimed at achieving intestinal autonomy should be tried: use of trophic factors, intestinal tapering, and lengthening. In a few residual patients, permanent intestinal failure or extreme short bowel syndrome require intestinal transplantation.

Long-term follow-up after bowel resection for necrotizing enterocolitis: factors affecting outcome

BACKGROUND

Necrotizing enterocolitis (NEC) is the most common surgical emergency among newborns and is associated with a high morbidity and mortality. This study evaluates the long-term survival of infants requiring surgical intervention for NEC and factors affecting outcome.

METHODS

A retrospective review of infants requiring surgery for complications of NEC at a tertiary care, pediatric hospital over a 16-year period was performed. Patients were evaluated for early and late morbidity and mortality, length of intestinal resection, presence of the ileocecal valve (ICV), days of parenteral nutrition (PN), and growth.

RESULTS

Two hundred forty-nine patients were included, with an average gestational age of 30 +/- 5 (+/- SD) weeks and birth weight of 1.50 +/- 0.89 kg. The surgical mortality rate was 45%, with survivors (137) being larger (P < .001) and older (P < .001) at time of birth than nonsurvivors. Mortality rates varied inversely with gestational age and birth weight. Surgical survivors had an average of 21 +/- 26 cm of intestinal length resected. The ileocecal valve was preserved in 45% of infants. Growth was similar between infants with or without an ICV. Stratification of length of intestine resected showed that infants with larger resections had greater requirements for parenteral nutrition, but this had no influence on long-term growth at follow-up.

CONCLUSIONS

Survivors of NEC are characterized by greater gestational age, greater birth weight, and older postgestational age at surgery. Infants who underwent greater intestinal resections required longer periods of PN. The length of intestine resected or presence of the ileocecal valve had no overall bearing on long-term outcome.

Reducing parenteral requirement in children with short bowel syndrome: impact of an amino acid-based complete infant formula

BACKGROUND

The aim of this study was to assess the impact of an amino acid-based complete infant formula on enteral feeding tolerance and parenteral nutrition requirement in children with severe short bowel syndrome.

METHODS

Four children (23 months-4.75 years) with short bowel syndrome who required long-term parenteral nutrition due to persistent feeding intolerance while receiving an extensively hydrolyzed formula were assessed before and after the commencement of an amino acid-based complete infant formula for a mean follow-up period of 48 months (range 39-51 months). Assessment included clinical monitoring of feeding tolerance and nutritional status, biochemistry, stool analysis, skin-prick testing to common food antigens, esophagogastroduodenoscopy and colonoscopy or jejunoscopy with biopsies, and measurement of disaccharidase levels and intestinal permeability.

RESULTS

All patients ceased parenteral nutrition within 15 months as a result of decreased stool output and resolution of vomiting. Patients had a reduction in hospitalization (mean: 198 versus 98 days/patient/year), episodes of proven (mean: 4.3 versus 3.3/patient/year) and suspected (mean: 6.5 versus 4.0/ patient/year) bacterial sepsis and central line insertions (mean: 2.5 versus 1.5/patient/year). Intestinal permeability to lactulose fell markedly (mean: 69% versus 2.7%). Disaccharidase levels increased in all three patients undergoing repeat studies.

CONCLUSIONS

An amino acid-based complete infant formula improved feeding tolerance and eliminated the need for parenteral nutrition in four children with short bowel syndrome who had previously required long-term parenteral nutrition. The clinical improvement was mirrored by improvement in measurements of intestinal function.

Predicting the duration of dependence on parenteral nutrition after neonatal intestinal resection

OBJECTIVE

To determine whether there are clinical or physical factors that could be used to predict the duration of dependence on parenteral nutrition (PN) in infants who have undergone resection of small intestine in the neonatal period.

STUDY DESIGN

Medical records of 44 patients who had small intestinal resection as neonates from 1985 to 1996 and who were dependent on PN for at least 3 months were reviewed. Statistical evaluation of patient variables and their impact on duration of dependence on PN were determined by using the Cox Proportional Hazard model.

RESULTS

Twenty-seven patients became independent of PN before the age of 36 months. Seven patients between 40 and 129 months of age are permanently dependent on PN. Outcome could not be determined in 10 patients, four of whom died of hepatic failure while still receiving PN and six of whom are still receiving PN but are younger than 36 months of age. Small bowel length after initial surgery and the percent of daily energy intake received by the enteral route at 12 weeks' adjusted age were significantly related to the duration of dependence on PN. Gestational age, presence of the ileocecal valve, and development of cholestasis were not significantly related. With the use of the Cox Proportional Hazards survival model, a formula was generated to allow estimation of the duration of dependence on PN.

CONCLUSIONS

The duration of dependence on PN can be predicted at an early age in neonatal short bowel syndrome by using two patient variables: the length of residual small bowel after initial surgery and the percent of daily energy intake tolerated through the enteral route.

Small-intestinal transplantation

The management of patients with intestinal failure has benefited from progress in parenteral nutrition (PN), especially home-based PN. Intestinal transplantation is therefore possible and is now, in some conditions, the logical therapeutic option. Since 1985, more than 180 small-bowel grafts have been done, involving the isolated small bowel with or without the colon (38%), the liver-small bowel (46%) or several organs (16%). Two-thirds of recipients were under 20 years of age, and indications were short-bowel syndrome (64%), severe intractable diarrhoea (13%), abdominal cancer (13%) or chronic intestinal pseudo-obstruction syndrome (8%). Of the patients, 51% survived > 2 years after the graft. Patient and graft survival depends on the type of immunosuppression, i.e. cyclosporine or FK506. The results must be interpreted carefully as they represent the first experience in numerous centres using different immunosuppressive protocols, without any randomization. The results from the largest of these centres reflect the current situation more closely. Functional grafts lead to gastrointestinal autonomy (weaning of PN) while maintaining satisfactory nutritional status and normal growth in childhood. Intestinal transplantation is theoretically indicated for all patients permanently or dependent for a long time on PN. However, as PN is generally well tolerated, even for long periods, each indication for transplantation must be carefully weighed up in terms of the iatrogenic risk and quality of life. When PN has reached its limits, especially in those associated with vascular, infectious, hepatic or metabolic complications, intestinal transplantation must be undertaken. Transplantation of the small bowel alone remains the first option, as combined liver-small bowel grafting is only indicated in the case of life-threatening progressive cirrhogenic liver disease.

Influence of bacterial overgrowth and intestinal inflammation on duration of parenteral nutrition in children with short bowel syndrome

OBJECTIVES

Massive intestinal resection results in short bowel syndrome and necessitates prolonged parenteral feeding. The purpose of this work was to assess the impact of late complications of short bowel syndrome, including intestinal bacterial overgrowth and enterocolitis, on the duration of parenteral nutrition (PN) in comparison with factors evident in the neonatal period.

METHODS

Retrospective chart review.

RESULTS

Of 49 children, 42 were weaned from parenteral nutrition after a treatment course of 17 +/- 14 months. In these 42, postresection small intestinal length equaled 81 +/- 65 cm; 45% had an ileocecal valve. Small intestinal length in the seven children who were PN dependent was 31 +/- 30 cm (p < 0.05); none had an ileocecal valve (p < 0.05). Bacterial overgrowth occurred in all seven PN-dependent children and in 23 of 42 children eventually weaned from PN (p < 0.05). When bacterial overgrowth was identified before weaning (n = 12), the duration pf PN was 28 +/- 17 months, but when bacterial overgrowth was first identified only after weaning (n = 11), the duration of PN was 16 +/- 13 months (p < 0.05). Small intestinal inflammation correlated with bacterial overgrowth (r = 0.69). Those children with severe enteritis identified before weaning remained on the PN regimen for 36 +/- 15 months, in comparison with 21 +/- 14 months in those with mild enteritis and 13 +/- 11 months in those without inflammation (p < 0.02).

CONCLUSIONS

Although the length of small intestine remaining after resection is the best immediate predictor of final success in terminating PN in children with short bowel syndrome, PN is prolonged by bacterial overgrowth and associated enteritis in those who will ultimately be weaned.