Short bowel syndrome in children and small intestinal transplantation

Complementary food introduction practices in infants with intestinal failure

BACKGROUND

Oral intake in infants with intestinal failure (IF) may be limited due to intolerance or feeding difficulties. Guidelines for the introduction of semisolid or solid complementary foods (CFs) to infants with IF do not exist. CF intake and caloric contribution from CF is difficult to assess due to malabsorption and incomplete recording. The aim of this study was to identify institutional approaches to introducing CF to infants with IF.

METHODS

The American Society for Parenteral and Enteral Nutriton (ASPEN) Pediatric Intestinal Failure Section Registered Dietitian/Nutritionist (RDN) working group designed a 10-question online cloud-based survey to assess group member practice related to the introduction of CF to infants with IF.

RESULTS

Twenty-six surveys were completed. Thirteen (50%) RDNs recommend introduction of CF between 4 and 6 months of age. Nineteen (76%) recommend adding pureed foods to gastrostomy tube feedings. Seventeen (65%) follow standard infant feeding practice guidelines with half citing the American Academy of Pediatrics. Approximately half (44%) recommend introducing vegetables first and the majority (80%) recommend delaying the introduction of fruits. The vast majority (92%) recommend specific foods to minimize stool output including green beans, bananas, infant cereals, and meats/protein.

CONCLUSION

Institutional practices related to the introduction of CF to infants with IF vary. Similarities with first food choice and foods to avoid were observed. Evidenced-based practice guidelines for the introduction of CF to infants with IF need to be established to determine best practices for reducing stool output, encouraging weaning from parenteral nutrition, and achieving enteral autonomy.

Nutritional Management of Short Bowel Syndrome

Short bowel syndrome (SBS) of infancy is a cause of prolonged morbidity with intolerance to enteral feeding, specialized nutritional needs, and partial/total dependence on parenteral nutrition. These infants can benefit from individualized nutritional strategies to support and enhance the process of intestinal adaptation. Early introduction of enteral feeds during the period of intestinal adaptation is crucial, even though the enteral feedings may need to be supplemented with an effective, safe, and nutritionally adequate parenteral nutritional regimen. Newer generation intravenous lipid emulsions can be effective in preventing and treating intestinal failure-associated liver disease. Prevention of infection(s), pharmaceutical interventions to enhance bowel motility and prevent/mitigate bacteria overgrowth, and specialized multidisciplinary care to minimize the injury to other organs such as the liver, kidneys, and the brain can assist in nutritional rehabilitation and lower the morbidity in SBS.

Management of pediatric intestinal failure related to short bowel syndrome

Intestinal failure (IF) secondary to short bowel syndrome is a challenging and complex medical condition with significant risk for surgical and medical complications. Significant advancements in the care of this patient population have led to improved survival rates. Due to their intensive medical needs children with IF are at risk for long-term complications that require comprehensive management and close monitoring. The purpose of this paper is to review the available literature emphasizing the surgical aspects of care for children with IF secondary to short bowel syndrome. A key priority in the surgical care of this patient population includes strategies to preserve available bowel and maximize its function. Utilization of novel surgical techniques and autologous bowel reconstruction can have a significant impact on children with IF secondary to short bowel syndrome related to the function of their bowel and ability to achieve enteral autonomy. It is also important to understand the potential long-term complications to ensure strategies are put in place to mitigate risk with early detection to improve long-term outcomes.

ASPEN definitions in pediatric intestinal failure

Pediatric intestinal failure (PIF) is a relatively rare disease entity which requires focused interdisciplinary care and specialized nutrition management. There has long been a lack of consensus in the definition of key terms related to PIF due to its rarity and plethora of small studies rather than large trials. As such, the American Society for Parenteral and Enteral Nutrition (ASPEN) Pediatric Intestinal Failure Section, composed of clinicians from a variety of disciplines caring for children with intestinal failure, is uniquely poised to provide insight into this definition void. This document is the product of an effort by the Section to create evidence-based consensus definitions, with the goal of allowing for appropriate comparisons between clinical studies and measurement of longterm patient outcomes. This manuscript was approved by the ASPEN Board of Directors. This article is protected by copyright. All rights reserved.

Invariant natural killer T cells infiltrate intestinal allografts undergoing acute cellular rejection

Immunological responses in human intestinal allografts are poorly understood and accurate diagnosis of acute cellular rejection remains difficult. Here, human intestinal allografts were analyzed by multi-color quantitative fluorescent immunohistochemical morphometry in order to monitor the clinical course of rejection. Morphometry gave two-dimensional plots based on size and circularity, and identified phenotypes of individual cells infiltrating the allograft by fluorescent staining. Using this method, invariant TCRVα24(+) NKT (iNKT) cells were observed in the intestinal allograft during rejection. Because these were not identified in the normal donor intestine before surgery, this finding was considered to be a signature of acute cellular rejection of the intestinal allograft. Infiltrating iNKT cells released IL-4 and IL-5, Th2-related cytokines that antagonize the Th1 responses that induce acute cellular rejection. Histological observation suggested eosinophilic enteritis in the mucosa with elevation of IL-4 and IL-5. In conclusion, iNKT cells were recruited to the intestine; however, because higher levels of IL-4 and IL-5 may contribute to eosinophilic enteritis, timely steroid administration is recommended for allograft injury due to enteritis, as well as acute cellular rejection.

Pediatric short-bowel syndrome: the cost of comprehensive care

BACKGROUND

Little information is available about the financial charges incurred by patients with short-bowel syndrome (SBS). This is particularly true for pediatric SBS patients who receive some of the most complex medical care.

OBJECTIVES

The aims of this study were to determine the total cost of care for these patients and to analyze their utilization of home and hospital-based health care services.

DESIGN

This was a retrospective review of the total charges incurred by 41 children with SBS over the past decade, encompassing both inpatient and home-care charges.

RESULTS

The mean (+/- SD) total cost of care for pediatric SBS was US$505 250 +/- US$248 398 (corrected for inflation to the year 2005) for the first year of care alone. Inpatient hospitalization accounted for most of these expenses (US$416 818 +/- US$242 689, or 82% of the total), and this was attributable to prolonged requirements for intensive care resources, numerous surgical procedures, and multiple readmissions during the first year of diagnosis. Hospital-based costs steadily declined in subsequent years, but home-care services, in stark contrast, unexpectedly increased every year for the first 5 y of diagnosis-a trend that was highly significant (P < 0.005), reaching US$184 520 +/- US$111 075 for the fifth year of home care. This increasing cost was attributable to increasing complications of parenteral nutrition, especially infectious complications. Although per-patient charges varied widely, the mean total cost of care per child over a 5-y period was US$1 619 851 +/- US$1 028 985. A strong correlation was found between higher charges and infants with <10% of predicted small-bowel length.

CONCLUSIONS

This study was the first to calculate the total costs for pediatric SBS patients and to provide an in-depth analysis of these patients' actual utilization of health care services. This information may help guide health care providers and families who have children with SBS. The comprehensive care of pediatric SBS patients costs significantly more than has previously been estimated. Contrary to previous views, home care significantly increases each year after diagnosis.

Gut hormones, and short bowel syndrome: The enigmatic role of glucagon-like peptide-2 in the regulation of intestinal adaptation

Short bowel syndrome (SBS) refers to the malabsorption of nutrients, water, and essential vitamins as a result of disease or surgical removal of parts of the small intestine. The most common reasons for removing part of the small intestine are due to surgical intervention for the treatment of either Crohn's disease or necrotizing enterocolitis. Intestinal adaptation following resection may take weeks to months to be achieved, thus nutritional support requires a variety of therapeutic measures, which include parenteral nutrition. Improper nutrition management can leave the SBS patient malnourished and/or dehydrated, which can be life threatening. The development of therapeutic strategies that reduce both the complications and medical costs associated with SBS/long-term parenteral nutrition while enhancing the intestinal adaptive response would be valuable.

Currently, therapeutic options available for the treatment of SBS are limited. There are many potential stimulators of intestinal adaptation including peptide hormones, growth factors, and neuronally-derived components. Glucagon-like peptide-2 (GLP-2) is one potential treatment for gastrointestinal disorders associated with insufficient mucosal function. A significant body of evidence demonstrates that GLP-2 is a trophic hormone that plays an important role in controlling intestinal adaptation. Recent data from clinical trials demonstrate that GLP-2 is safe, well-tolerated, and promotes intestinal growth in SBS patients. However, the mechanism of action and the localization of the glucagon-like peptide-2 receptor (GLP-2R) remains an enigma. This review summarizes the role of a number of mucosal-derived factors that might be involved with intestinal adaptation processes; however, this discussion primarily examines the physiology, mechanism of action, and utility of GLP-2 in the regulation of intestinal mucosal growth.

Surgical therapy for short bowel syndrome

Patients with short bowel syndrome (SBS) suffer tremendous morbidity secondary to prolonged hospitalization and chronic parenteral nutrition (TPN). Overall, the majority of infants will adapt and ultimately become independent of TPN, but this process may require many months or years. Reasons for continued TPN dependency include bowel dysmotility, bacterial overgrowth, insufficient adaptation, or very short bowel length. It is this subpopulation of patients who may benefit from surgical procedures that optimize intestinal adaptation and increase the mucosal absorptive surface area. The goal of this review article is to summarize the process of intestinal adaptation and then to outline the surgical principles and techniques available to surgeons who treat this complicated group of patients.

GLP-2 levels in infants with intestinal dysfunction

Glucagon Like Peptide 2 (GLP-2) has been proposed as an important regulatory hormone in nutrient absorption. The present study was conducted in human infants with intestinal dysfunction undergoing surgery, correlating postprandial GLP-2 levels with intestinal length, nutrient absorption, and patient outcome. We hypothesized that GLP-2 levels would be inversely related to nutrient absorption; we further hypothesized that post prandial GLP-2 levels would be predictive of the ability to wean patients from total parenteral nutrition (TPN), and tolerance of enteral feeding. Infants prospectively identified with nutrient malabsorption following intestinal surgery were monitored and after initiation of feeds GLP-2 levels were measured in the fed state. Intestinal length was recorded intraoperatively and nutrient absorption was quantified using both a balance study, and carbohydrate probe method. 12 infants had GLP-2 levels successfully measured; two patients had repeated studies. Average gestational age was 32.7 +/- 3.4 wk, age at testing was 1.7 +/- 1.4 mo and average weight was 3.5 +/- 1.1 kg. Causes of intestinal loss were necrotizing enterocolitis, atresia and volvulus. Five patients had severe short bowel syndrome (<50% of normal small intestinal length), 3 died. GLP-2 levels were best correlated with residual small intestinal length (r2 = 0.75). Correlations with total intestinal length including colon were less significant; residual colon appeared to not contribute to measurable GLP-2 production. GLP-2 levels were well correlated with tolerance of enteral feeds. Contradicting the initial hypothesis, GLP-2 levels were directly correlated with nutrient absorptive capacity (correlation with fat absorption: r2 = 0.72, carbohydrate = 0.50 and protein = 0.54 respectively). There were no apparent changes in GLP-2 levels with gestational or postnatal age. As a corollary to the correlation with bowel length, a postprandial level of 15 pmol/L appeared to be discriminatory; infants with postprandial GLP-2 levels of > 15 pmol/L were able to be weaned from total parenteral nutrition, while 3 of 4 infants who had GLP-2 levels less than 15 could not be weaned by one year. These results show that in infants with intestinal dysfunction, GLP-2 levels are correlated with residual small bowel length and nutrient absorption, and may be predictive of outcome. In contrast to adults with intact colon and SBS, infants with SBS and intact colon do not appear able to produce GLP-2 in response to feeding stimulation. Further studies are suggested to examine the ontogeny of the GLP-2 axis and the possible therapeutic role of GLP-2 supplementation.

Mucous fistula refeeding in premature neonates with enterostomies

BACKGROUND

Premature neonates with short bowel syndrome often have diverting enterostomies and distal mucous fistulae. The authors reviewed their experience in 12 premature neonates in whom proximal bowel contents were re-fed into the mucous fistula.

METHODS

We reviewed the records of 12 premature neonates who presented with acute abdomen and who underwent intestinal resection with formation of diverting enterostomy and mucous fistula between July 1999 and December 2002. All received parenteral nutrition. Refeeding of enterostomy contents into the distal mucous fistula was commenced after patency of the distal intestine was confirmed by radiologic examination. Demographic data, body weight and clinical outcomes were recorded.

RESULTS

Median gestational age was 31 weeks and mean birth weight was 1.59 kg. Diagnoses included necrotizing enterocolitis (n = 6), meconium ileus-like conditions (n = 2), ileal atresia (n = 2), malrotation with volvulus (n = 1) and focal intestinal perforation (n = 1). Refeeding was successfully established in all patients with no complications. The mean duration of refeeding was 63.5 days. All patients achieved good weight gain after refeeding (18.9 +/- 2.9 g/d) with a reduction of parenteral nutrition requirements. All enterostomies were subsequently closed. Four patients died of unrelated causes after reanastomosis and the remaining eight were discharged.

CONCLUSIONS

Mucous fistula refeeding is safe in premature neonates with enterostomies. It can prevent disuse atrophy in the distal loop and facilitate subsequent reanastomosis. Furthermore, the increased absorptive function provided by the small bowel incorporated in the mucous fistula can reduce the requirement for total parenteral nutrition.

Glucagon-like peptide-2 induces intestinal adaptation in parenterally fed rats with short bowel syndrome

Glucagon-like peptide-2 (GLP-2) is an intestinal trophic enteroendocrine peptide that is associated with intestinal adaptation following resection. Herein, we investigate the effects of GLP-2 in a total parenteral nutrition (TPN)-supported model of experimental short bowel syndrome. Juvenile Sprague-Dawley rats underwent a 90% small intestinal resection and jugular catheter insertion. Rats were randomized to three groups: enteral diet and intravenous saline infusion, TPN only, or TPN + 10 microg.kg(-1).h(-1) GLP-2. Nutritional maintenance was isocaloric and isonitrogenous. After 7 days, intestinal permeability was assessed by quantifying the urinary recovery of gavaged carbohydrate probes. The following day, animals were euthanized, and intestinal tissue was processed for morphological and crypt cell proliferation (CCP) analysis, apoptosis (caspase-3), and expression of SGLT-1 and GLUT-5 transport proteins. TPN plus GLP-2 treatment resulted in increased bowel and body weight, villus height, intestinal mucosal surface area, CCP, and reduced intestinal permeability compared with the TPN alone animals (P < 0.05). GLP-2 treatment induced increases in serum GLP-2 levels and intestinal SGLT-1 expression (P < 0.01) compared with either TPN or enteral groups. No differences were seen in the villus apoptotic index between resection groups. Enterally fed resected animals had a significant decrease in crypt apoptotic indexes compared with nontreated animals. This study demonstrates that GLP-2 alone, without enteral feeding, stimulates indexes of intestinal adaptation. Secondly, villus hypertrophy associated with adaptation was predominantly due to an increase in CCP and not to changes in apoptotic rates. Further studies are warranted to establish the mechanisms of action and therapeutic potential of GLP-2.

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.

Influence of diet complexity on intestinal adaptation following massive small bowel resection in a preclinical model

AIMS

To investigate the effect of dietary complexity on intestinal adaptation using a preclinical model.

METHODS

Four-week-old piglets underwent a 75% proximal small bowel resection or transection operation (control). Post-operatively, animals received either pig chow (n = 15), polymeric formula (n = 9), polymeric formula plus fiber (n = 6), or elemental formula (n = 7).

RESULTS

The weight gain of all groups was reduced compared with controls that were fed the same diet. Animals that had a resection, which were fed elemental formula, had significantly reduced weight gain compared with the other groups (4.7 4.2 vs 30.7 7.1 kg chow and 11.5 1.3 kg polymeric formula). Villus height was increased in the jejunum, ileum and terminal ileum of resected animals compared with controls in animals fed with pig chow, polymeric formula and elemental formula. The animals that had a resection had a significant reduction in the transepithelial conductance (10.4 5.5 vs 25.4 6.5 mS/cm2) and 51Chromium-EDTA flux (2.8 1.9 vs 4.8 4.9 microL/h per cm2) compared with the controls.

CONCLUSIONS

A complex diet was found to be superior to an elemental diet in terms of the morphological and functional features of adaptation following massive small bowel resection.

Analysis of the effect of intestinal resection on rat ileal bile Acid transporter expression and on bile Acid and cholesterol homeostasis

Ileal reclamation of bile salts is mediated in large part by an apical sodium-dependent bile acid transporter (ASBT) located in the terminal ileum. The following studies were performed to elucidate the adaptive response of ASBT to intestinal resection. Two separate series of intestinal resections were performed: 1) limited (25%) ileal and 2) massive (70%) intestinal resection. The boundaries of the resections were varied to examine differences in compensation when variable amounts of endogenous transporter activity were resected. Previously demonstrated supraphysiologic expression of ASBT, which was seen after proximal ileal resection, led to a contraction in the bile acid pool size and a paradoxical reduction in bile acid (cholesterol 7alpha-hydroxylase and sterol 27-hydroxylase) and cholesterol (hydroxymethylglutaryl coenzyme A reductase) biosynthetic enzyme activities. Massive intestinal resection resulted in ileal hypertrophy and an apparently maladaptive specific down-regulation in ASBT protein expression. In this model bile acid pool size correlated with the amount of residual ASBT-expressing terminal ileum. Cholesterol and bile acid biosynthetic enzyme activities were inversely related to bile acid pool size. Adaptive changes in ASBT expression and alterations in bile acid and cholesterol homeostasis are dependent on the type and location of intestinal resection.

Virtue ethics in a pluralistic world

The practice of pediatric surgery is at the crossroads of 2 specialties, pediatrics and surgery. At that vantage point, many ethical dilemmas can be seen. It is important for the pediatric surgeon to understand the special place of ethics in the care of children and how that care is influenced by society. The purpose of this report is to introduce the perspective of virtue ethics as an avenue to problem solving in ethical dilemmas in pediatric surgery. Virtue ethics relies more on the physician-focused view of character and ideal behavior as opposed to more patient-based rules of action. This ethical theory must be placed on the background of our changing society with an increasing plurality of values. The medical community of pediatric surgery must remain involved in the dialogue concerning these dilemmas in the care of children.

Ethical challenges in the care of infants with intestinal failure and lifelong total parenteral nutrition

Families, pediatric surgeons, and other care givers face difficult ethical challenges as they balance the benefits and burdens of total parenteral nutrition (TPN) and bowel transplantation in the face of uncertainty and the inability to predict which infants with intestinal failure are likely to have good outcomes. This article presents an analysis of 3 TPN cases using a comparison with dialysis and kidney transplantation, an older and more established technology for which ethical guidelines are proposed in the literature. The authors conclude that pediatric surgeons should recommend TPN in cases in which it is expected to be a temporary measure until bowel function is restored. TPN should not be recommended when other comorbidities make survival unlikely or when the infant is neurologically devastated. In the case of lifelong TPN in which bowel transplantation is only an option when TPN fails, pediatric surgeons should defer to parents in their choice about the use of lifelong TPN.

Systemic GLP-2 levels do not limit adaptation after distal intestinal resection

BACKGROUND/PURPOSE

Glucagonlike peptide 2 (GLP-2) is trophic for the small bowel; it is produced by L cells in the distal intestine in response to luminal nutrients. This study tests the hypothesis that distal small bowel and cecal resection would decrease GLP-2 levels and reduce adaptation.

METHODS

Male Sprague-Dawley rats (200 to 300 g) underwent either ileal transection (controls) or resection of the ileum and cecum, leaving 10 or 20 cm jejunal remnant anastomosed to the ascending colon. Animals were followed up for up to 21 days. Endpoints were daily weights, intestinal histology, in vivo absorption of 3-0 methylglucose (a measurement of active nutrient absorptive capacity), and serum GLP-2 levels.

RESULTS

The control group had a maximum 6% weight loss around day 2, and then recovered with a steady weight gain. The 10-cm jejunal remnant group lost weight continuously and never recovered postsurgery. The 20-cm jejunal remnant group of animals had a maximum of 12% weight loss by day 4 and then slowly gained weight. The average villus height increased significantly (P <.01) in the 10-cm and 20-cm jejunal remnant groups compared with controls. Absorption of 3-0 methylglucose was significantly decreased (P <.01) in both resected groups. Serum GLP-2 levels were increased significantly (P <.05) when compared with controls in both resection groups.

CONCLUSIONS

Increased serum GLP-2 levels were found in the ileocecal resection rat model, and these levels correlated with morphologic adaptation. However, this morphologic adaptation was not sufficient to restore nutrient absorption as shown by weight changes and 3-0 methylglucose absorption. Thus, the original hypothesis of this study is incorrect: systemic GLP-2 levels do not limit adaptation following distal ileocecal resection.

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.

Coordinated interdisciplinary management of pediatric intestinal failure: a 2-year review

BACKGROUND/PURPOSE

Intestinal failure is a complex metabolic process that results from malabsorption and malnutrition and provides challenges for a variety of pediatric subspecialists. The purpose of this study was to evaluate the effect of coordinated interdisciplinary team management of children with intestinal failure on nutritional outcome measures.

METHODS

The Intestinal Care Center (ICC) is staffed with an interdisciplinary team of pediatric specialists including a gastroenterologist, pediatric surgeon, transplant surgeon, clinical dietitians, and a nutrition support nurse. Using an established registry, the authors conducted a comprehensive evaluation of patient data including anthropometric measures, organ system function, and mode of nutrition support. Disease-associated complications including micronutrient deficiencies, growth delay, and death also were monitored. Nutritional outcome was assessed by transition from enteral to oral feeding, cessation of total parenteral nutrition (TPN), and maintenance of linear growth.

RESULTS

Since the inception of the ICC in 1996, 103 patients (69 boys, 34 girls) with intestinal failure have been evaluated with a median age of 2.6 years (range, 0.2 to 21.3 years). Mode of nutritional therapy on initial consultation included TPN (n = 76, 74%), enteral feedings (n = 6, 6%) and oral intake (n = 21, 20%). After intensive management of the 76 patients who were TPN dependent, 22 (29%) subsequently have been weaned from TPN (duration, 0.2 to 17.5 years) to oral (n = 14), oral-enteral (n = 4) or enteral feedings (n = 4). Of the 6 patients who were receiving enteral feedings, 4 (67%) were transitioned to oral feedings. Sixty-eight patients (66%) had evidence of hepatic disease. Of these, 10 underwent transplant, and 23 died (2 posttransplant). Linear growth velocity of neither pre- nor postpubescent patients significantly improved during the 2-year study period.

CONCLUSION

Data registry establishment and concurrent interdisciplinary team management of children with intestinal failure provides for innovative treatment approaches and a foundation for retrospective or prospective assessment of children with disease.

[Role of calcineurin-dependent drugs on the immunosuppressive effect induced by the anti-LFA-1 antibody in a fetal intestinal transplantation model in mice]

STUDY AIM

We have previously demonstrated that anti-LFA-1 monoclonal antibody (mAb) can efficiently protect against rejection of small bowel allograft in a mouse model. The aim of the present work was to determine, in the same model, the optimum conditions for utilisation of anti-LFA-1 mAb and the effects of calcineurin-dependent drugs on the immunosuppression induced by anti-LFA-1 mAb treatment.

MATERIALS AND METHODS

Foetal small intestines of C57Bl/6 (H-2b) mice were transplanted into adult C3H/He (H-2k) mice. Recipients were treated with anti-LFA-1 mAb alone (with or without day-1 injection), or combined to cyclosporin (20 mg.kg-1.j-1 for 14 days), or to tacrolimus (1 mg.kg-1.j-1 from day 0 to day 7). Biopsies were performed after engraftment from day 5 to day 30.

RESULTS

Administration of anti-LFA-1 mAb alone is sufficient to induce significant prolongation of intestinal allograft survival, provided that the treatment starts one day before engraftment. This tolerogenic effect is reversed by the transitory administration of tacrolimus (p = 0.008).

CONCLUSION

Treatment with anti-LFA-1 mAb has to be started before the allogeneic response has begun. Calcineurin-dependent drugs can modulate the tolerogenic effect induced by anti-LFA-1. A transgenic mice model should give precise details about underlying mechanisms of these interactions, before a possible utilisation of anti-LFA-1 mAb in intestinal transplantation in humans.

Long-term outcome of short bowel syndrome in adult and pediatric patients

We reviewed 12 pediatric and 18 adult patients with short bowel syndrome (SBS) from Osaka University Hospital and compared clinical characteristics between them. The length of the residual small intestine ranged from 0 to 75 cm (mean 47 cm) in pediatric patients and from 0 to 150 cm (mean 47 cm) in adult patients. In all cases, total parenteral nutrition (TPN) was started immediately after surgery and was gradually replaced by enteral nutrition. Eight pediatric patients (67%) and 4 adult patients (22%) were weaned from TPN. Residual intestinal length in these patients ranged from 27 to 75 cm (mean 57 cm) in pediatric patients and 57 to 150 cm (mean 96 cm) in adult patients. Pediatric patients with residual small intestinal lengths of 0, 16, 25, and 45 cm were not weaned from TPN. None of the adult patients with residual small intestinal length less than 40 cm could achieve complete intestinal adaptation. Five adult patients died due to liver failure (2 cases), heart failure (2 cases), or pneumonia (1 case), whereas all pediatric patients survived. The average life span of indwelling central venous catheters was 511 days and 780 days, and the rate of catheter-related sepsis per 1000 catheter days was 0.73 and 0.48 in pediatric and adult patients, respectively. Plasma levels of arginine and citrulline in patients receiving TPN were significantly decreased compared with those in patients receiving TPN without SBS both in pediatric and adult patients (p < .01). These results indicate that pediatric and adult patients with SBS can survive with TPN and enteral nutrition. The minimum remaining intestinal length necessary for complete bowel adaptation is shorter for pediatric patients than adults, suggesting better bowel adaptation in pediatric 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.

Limited ileal resection in infancy: the long-term consequences

BACKGROUND/PURPOSE

The longer-term sequelae of short bowel syndrome in infancy are reasonably well documented, but little is known about the long-term nutritional and metabolic effects of limited (less than 50 cm) ileal resection. This makes it difficult to formulate a rational follow-up policy in such children.

METHODS

All children who underwent limited ileal resection for either necrotizing enterocolitis (NEC) or intussusception at our institution between 1984 and 1992 were invited to attend a detailed clinical, anthropometric, hematologic, and biochemical assessment, together with a biliary and renal ultrasound scan and measurement of bone mineral density.

RESULTS

Twenty-four children (NEC, 17; intussusception, 7) of median age 7.4 years (range, 5.5 to 13.7 years) agreed to participate. Nine previously had undergone an isolated ileal resection, and 15 also had had variable lengths of colon removed. The length of resected ileum ranged from 3 to 44 cm, with a median of 10 cm. Seven control subjects in whom neonatal NEC developed but recovered without surgery were also evaluated. Median height, weight, and body mass index after ileal resection were between the 25th and 50th percentiles; no child was stunted or wasted. After ileal resection, one boy was found to have asymptomatic vitamin B12 deficiency, and three children had low plasma concentrations of vitamin A. Hematologic and biochemical parameters were otherwise normal apart from a few marginally low trace element levels in both subjects and controls. No renal calculi were detected, and bone mineral density measurements were normal in all except one child. Four children had cholelithiasis, all of whom had previously undergone limited ileal resection for NEC (two isolated, two ileocolic). Thus, the prevalence of cholelithasis after limited ileal resection for NEC was 24% at a median age of 7.0 years.

CONCLUSIONS

Growth and nutritional status are well preserved after limited ileal resection in infancy. Limited ileal resection for NEC is associated with a subsequent high prevalence of cholelithiasis and a risk of vitamin B12 deficiency. These findings are important when planning strategies for long-term follow-up.

Molecular basis of intestinal adaptation: the role of the insulin-like growth factor system

Ongoing and future approaches to the cellular and molecular actions of insulin-like growth factor I (IGF-I) and growth hormone (GH) in intestinal adaptation are reviewed. This is highly relevant to understanding the benefits and risks associated with increasing use of GH and IGF-I in patients with short bowel syndrome or other bowel diseases. As other growth factors share some of the properties of IGF-I including local expression in bowel, activation of signaling pathways common to other growth factors or cytokines, and modulation of action by growth factor-binding proteins or secreted receptor isoforms. The general issues and approaches outlined for IGF-I should, therefore, serve as a model for studies aimed at understanding the cellular and molecular mechanisms of action of other growth factors that are implicated in intestinal adaptation.

Treatment strategies for small bowel bacterial overgrowth in short bowel syndrome

BACKGROUND

Small bowel bacterial overgrowth is a common complication of short bowel syndrome, and although it is often controlled with antimicrobial therapy, alternative strategies may occasionally be needed.

METHODS

Six patients with bacterial overgrowth are described, who did not respond to antimicrobial therapy and required additional medical or surgical measures to control the overgrowth.

RESULTS

Recalcitrant bacterial overgrowth was successfully treated with periodic small bowel irrigation with a balanced hypertonic electrolyte solution, colonic flushes, encouraging frequent stooling, intestinal lengthening procedure, or probiotic therapy with Lactobacillus plantarum 299V and Lactobacillus GG.

CONCLUSIONS

Small bowel bacterial overgrowth should be aggressively evaluated in patients with short bowel syndrome who are not progressing in a normal manner. Inadequate or incomplete response to antibiotic therapy is common, and several additional treatment possibilities are available.

The approach to common abdominal diagnosis in infants and children

This article focuses on salient points in the evaluation of abdominal pain in infants and children. Specifically, the authors address appendicitis and abdominal pain associated with either vomiting, constipation, or gastrointestinal bleeding. A discussion of common abdominal masses, urologic, and gynecologic problems, and considerations in the evaluation of immunologically suppressed or neurologically impaired children, and children with recurrent abdominal pain is also presented. The authors establish logical, focused approaches to the initial evaluation and management of abdominal pain and suggest criteria for timely surgical referral.

[Prevention of intestinal allograft rejection by anti-adhesion molecule antibodies in a mouse model]

STUDY AIM

Small bowel transplantation is still hampered by a high morbidity and mortality linked to the heavy non specific immunosuppression which is required by the transplantation of this lymphoid organ. Adhesion molecules appear to be potential targets for specific immunosuppression. The aim of the study was to investigate the effect of a transitory administration of anti-LFA-1 or anti-alpha 4 monoclonal antibodies (mAb) in the prevention of rejection in a model of fetal small-bowel transplantation in mice.

MATERIALS AND METHODS

The small bowel of C57BL/6 (H-2b) fetus (16 to 20 days of gestation) was transplanted into adult C3H/He mice (H-2k) or C57BL/6 recipient mice. Recipients were treated with a short course of either anti-LFA-1 mAb alone, either with anti-alpha 4 mAb alone, or with both mAb. Biopsies with histological study of the grafts were performed between post-operative day 5 and 60. A score of development and rejection was assigned to each sample.

RESULTS

Normal intestinal development with no sign of rejection was observed in 24/28 syngenic grafts till post-operative day 45. In the absence of treatment, intense rejection was observed as soon as day 5 and all allogenic grafts were rejected (n = 22). In contrast, in anti-LFA-1 mAb treated mice, 18/20 allogenic grafts developed normally with minimal signs of rejection. In anti-alpha 4 treated mice, a transient protective effect on small bowel allograft survival was observed on day 7 but thereafter, all grafts were massively rejected within a few days (n = 18). The combination of both mAb didn't improve the survival of the grafts when compared to anti-LFA-1 mAb treated grafts (n = 10).

CONCLUSION

These results demonstrate that a transitory administration of anti-LFA-1 mAb, but not of anti-alpha 4 mAb, is able to prolong significantly the survival of non vascularized small bowel fetal grafts in mice. Our results are promising for the possible use of the anti-LFA-1 mAb in clinical intestinal transplantation.