Etiology and initial management of short bowel syndrome

Clinical challenges of short bowel syndrome and the path forward for organoid-based regenerative medicine

Short bowel syndrome (SBS) is a rare condition, the main symptom of which is malabsorption following extensive resection of the small intestine. Treatment for SBS is mainly supportive, consisting of supplementation, prevention and treatment of complications, and promotion of intestinal adaptation. While development of parenteral nutrition and drugs promoting intestinal adaptation has improved clinical outcomes, the prognosis of patients with SBS remains poor. Intestinal transplantation is the only curative therapy but its outcome is unsatisfactory. In the absence of definitive therapy, novel treatment is urgently needed. With the advent of intestinal organoids, research on the intestine has developed remarkably in recent years. Concepts such as the "tissue-engineered small intestine" and "small intestinalized colon," which create a functional small intestine by combining organoids with other technologies, are potentially novel regenerative therapeutic approaches for SBS. Although they are still under development and there are substantial issues to be resolved, the problems that have prevented establishment of the complex function and structure of the small intestine are gradually being overcome. This review discusses the current treatments for SBS, the fundamentals of the intestine and organoids, the current status of these new technologies, and future perspectives.

About the Usage and Usability of Central Venous Catheters in Children with TPN: the Parents' Viewpoint

BACKGROUND

Medical devices are important components of medical care. Therefore, they must be safe and useful for patients. This study aimed to analyze the situation of children with central venous catheters (CVCs) for long-term parenteral nutrition from the parents' perspective with respect to patient safety and usefulness.

METHODS

An online cross-sectional survey was conducted using a quantitative research approach, with a German patient support group for children with chronic intestinal failure.

RESULTS

61 responses were collected between November 202 and January 2021. Concerning the usability of the CVCs, the caregivers assessed overall satisfaction, patient safety, usability, learnability of handling, "self-explanatory ability, " and mental load. Furthermore, various suggestions for improvements have been documented.

CONCLUSION

Although CVCs can cause a variety of complications in the context of long-term use, the usage for parents in everyday life is feasible. Insufficient fixation and protection outside of the body have been identified as unmet clinical needs. In addition to the underlying disease of chronic intestinal failure, the catheter adds an extra mental burden to families' lives. Furthermore, parents articulated the need for further information and training.

A Digestive Cartridge Reduces Parenteral Nutrition Dependence and Increases Bowel Growth in a Piglet Short Bowel Model

OBJECTIVE

To determine whether the use of an immobilized lipase cartridge (ILC) to hydrolyze fats in enteral nutrition (EN) reduces parenteral nutrition (PN) dependence in a porcine model of short bowel syndrome with intestinal failure (SBS-IF).

BACKGROUND

SBS-IF occurs after intestinal loss resulting in malabsorption and PN dependence. Limited therapeutic options are available for achieving enteral autonomy.

METHODS

Eleven Yorkshire piglets underwent 75% jejunoileal resection and were randomized into control (n=6) and treatment (n = 5) groups. PN was initiated postoperatively and reduced as EN advanced if predefined clinical criteria were fulfilled. Animals were studied for 14 days and changes in PN/EN calories were assessed. Intestinal adaptation, absorption, and nutrition were evaluated at the end of the study (day 15). Comparisons between groups were performed using analysis of covariance adjusted for baseline.

RESULTS

ILC animals demonstrated a 19% greater reduction in PN calories ( P < 0.0001) and higher mean EN advancement (66% vs 47% of total calories, P < 0.0001) during the 14-day experiment. Treatment animals had increased intestinal length (19.5 vs 0.7%, P =0.03) and 1.9-fold higher crypt cell proliferation ( P =0.02) compared with controls. By day 15, ILC treatment resulted in higher plasma concentrations of glucagon-like peptide-2 ( P = 0.02), eicosapentaenoic acid ( P < 0.0001), docosahexaenoic acid ( P = 0.004), vitamin A ( P = 0.02), low-density lipoprotein ( P = 0.02), and high-density lipoprotein ( P = 0.04). There were no differences in liver enzymes or total bilirubin between the two groups.

CONCLUSIONS

ILC use in conjunction with enteral feeding reduced PN dependence, improved nutrient absorption, and increased bowel growth in a porcine SBS-IF model. These results support a potential role for the ILC in clinical SBS-IF.

Intestinal failure among adults and children: Similarities and differences

Intestinal failure (IF) is a complex medical condition that is caused by a constellation of disorders, resulting in the gut's inability to adequately absorb fluids and nutrients to sustain hydration, growth, and survival, thereby requiring the use of parenteral fluid and/or nutrition. Significant advancements in intestinal rehabilitation have resulted in improved survival rates for individuals with IF. There are distinct differences, however, related to etiology, adaptive potential and complications, and medical and surgical management when comparing children with adults. The purpose of this review is to contrast the similarities and differences between these two distinct groups and provide insight for future directions, as a growing population of pediatric patients will cross into the adult world for IF management.

Self-Assembled Integrative Nutrient Carrier Platform Containing Green Tea Catechin for Short Bowel Syndrome Treatment

Extensive resection of the small intestine leads to the development of short bowel syndrome (SBS), which reduces the effective absorptive surface area of the intestine and predisposes patients to emaciation, malnutrition, and other severe symptoms. Herein, green tea catechin (-)-epigallocatechin gallate (EGCG) and ferrous ions (Fe²⁺ ) are utilized to construct a nutrient carrier platform that self-assembles with nutrients to form phenolic-based nutrient complexes (PNCs). PNCs effectively prolong the residence and absorption time of nutrients in the intestine. Further this platform is applied to integrate full nutrient formula, an enteral nutrition (EN) preparation containing a range of full nutrient components. In an SBS rat model, the prepared phenolic-based integrative nutrient complexes (PINCs) enhance nutritional status, improve anemia and immune function, as well as facilitate the growth of remaining intestinal villi and crypts, and maintain the integrity of the intestinal barrier. In addition, PINCs enable the modulation of gut microbial dysbiosis, enrich the abundance of beneficial bacteria, and have no toxic effects after the long-term ingestion. These results provide a proof of principle for the use of polyphenol-based nanocomplexes as EN preparation, offering a feasible strategy for both nutritional support and therapeutic perspectives for SBS treatment.

25 Years of a Standardized Technique for Living Donor Intestinal Transplantation: A Systematic Review

A safe, reproducible and standardized surgical technique for intestinal procurement and transplantation from a living donor (LD) was introduced in 1997 and has been used in the majority of cases since. The key principles are: 1. procurement of 180-200 cm of distal ileum in adults (about 60-150 cm in pediatric recipients depending on age and weight) on a vascular pedicle comprising the LD ileocolic vessels or terminal branches of the superior mesenteric vessels, 2. the terminal ileum (30-40 cm of the most distal ileum), the ileocecal valve and the cecum remain with the donor to not interfere with B12-absorption and bowel transit time, 3. systemic venous drainage with anastomoses between the LD ileocolic vessels and the recipient's infrarenal aorta and vena cava, and 4. restoration of recipient bowel continuity through proximal anastomosis and distal graft ileostomy for biopsy access and graft monitoring. Recipients of a successful LD intestinal transplant become total parenteral nutrition (TPN)-independent within a few weeks posttransplant. LD vs deceased donor (DD) intestinal transplants can be performed in a more timely fashion. Hence, LD (in contrast to DD) intestinal transplants are also pre-emptive procedures in patients with advanced, but still reversible, TPN-induced liver disease and help reduce the wait-list mortality for combined DD intestinal and liver transplants. Life-saving combined LD intestinal and liver transplants, albeit rare, have also been successfully performed either simultaneously or subsequently. There have been no reported deaths or major complications of living intestinal donors. A better metabolic profile has been reported in some donors post-donation. In total, 85 documented LD intestinal transplants have been performed worldwide at over 20 different transplant centers in 12 different countries. In about 70 transplants, the standardized technique was used. There has been no difference in outcome between LD vs DD intestinal transplants. Long-term studies have shown that > 10 year of graft function is not uncommon. Since the introduction of the standardized surgical technique, LD intestinal transplantation has evolved from an experimental to an established and standardized procedure.

Surgical Treatment of Short Bowel Syndrome—The Past, the Present and the Future, a Descriptive Review of the Literature

Short bowel syndrome (SBS) is a devastating disorder with both short- and long-term implications for patients. Unfortunately, the prevalence of SBS has doubled over the past 40 years. Broadly speaking, the etiology of SBS can be categorized as congenital or secondary, the latter typically due to extensive small bowel resection following diseases of the small intestine, e.g., necrotizing enterocolitis, Hirschsprung’s disease or intestinal atresia. As of yet, no cure exists, thus, conservative treatment, primarily parenteral nutrition (PN), is the first-line therapy. In some cases, weaning from PN is not possible and operative therapy is required. The invention of the longitudinal intestinal lengthening and tailoring (LILT or Bianchi) procedure in 1980 was a major step forward in patient care and spawned further techniques that continue to improve lives for patients with severe SBS (e.g., double barrel enteroplasty, serial transverse enteroplasty, etc.). With this review, we aim to provide an overview of the clinical implications of SBS, common conservative therapies and the development of operative techniques over the past six decades. We also provide a short outlook on the future of operative techniques, specifically with respect to regenerative medicine.

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.

An in-line digestive cartridge increases enteral fat and vitamin absorption in a porcine model of short bowel syndrome

BACKGROUND & AIMS

Short bowel syndrome (SBS) occurs after intestinal loss resulting in parenteral nutrition dependence and micronutrient deficiencies, which may lead to life-limiting complications. ALC-078 is a cartridge containing immobilized lipase that connects in-line with enteral feeding sets and digests fats in enteral nutrition (EN). In this study, we evaluate the efficacy of ALC-078 to improve fat and nutrient absorption in a porcine SBS model.

METHODS

Fifteen male Yorkshire piglets were assessed. Animals were randomized to no intestinal resection (n = 5), 75% resection (n = 5), or 75% resection + ALC-078 (n = 5). After recovery, animals were treated for 14 days. Piglets received 60% of nutrition from continuous EN and 40% from chow. The degree of fat malabsorption was determined by the coefficient of fat absorption (CFA) following a 72-h stool collection. Body weight, fat-soluble vitamins, and nutritional markers were assessed.

RESULTS

Adverse events were similar across the three groups (P = 1.00). ALC-078-treated animals had similar weight gain compared to resected piglets. Resected animals had a lower CFA compared to unresected controls (79.3% vs. 95.2%, P = 0.01) while there was no significant difference in the ALC-078 animals (87.1% vs. 95.2%, P = 0.19). Between Study Days 1 and 15, ALC-078 animals had increased concentrations of vitamin D (12.2 vs. 8.7 ng/mL, P = 0.0006), and vitamin E (4.3 vs. 2.5 mg/L, P = 0.03). These markers did not significantly change in untreated resected animals.

CONCLUSION

ALC-078 increases the absorption of fat-soluble vitamins and may improve fat malabsorption. Future studies should determine whether ALC-078 can reduce PN dependence and if these findings translate to human patients with SBS.

Serial transverse enteroplasty and nipple valve construction, two life saving techniques for patients with short bowel syndrome, a report of 5 cases

Background

Various abdominal pathologies end up with surgical resection of small intestine. When the small intestine remnant is too short for adequate fluid and micronutrients absorption, short bowel syndrome is diagnosed. The disabling condition needs a multidisciplinary approach to design parenteral nutrition, care for thrombotic, hepatic and infectious complications and gradually wean the patient from parenteral nutrition. Various surgical techniques have been introduced to increase absorptive mucosa and enhance the intestinal adaptation process. Serial transverse enteroplasty and nipple valve reconstruction are among the procedures, which will be discussed in the current article.

Case presentation

Herein, we presented 5 cases of short bowel syndrome as a consequence of abdominal laparotomies, patients were referred to our center to receive parenteral nutrition and to be prepared for the final autologous gastrointestinal reconstruction or intestinal transplantation, if indicated.

Conclusion

Patient’s age, performance status and bowel remnant length determines the appropriate technique for autologous gastrointestinal reconstruction. Serial transverse enteroplasty is designed to increase bowel’s length by creating zigzag patterns through dilated bowel loops. Presence of ileocecal valve is crucial to delay intestinal transit time and to prevent colonic bacterial transfer to ileum. Patient’s with ileocecal valve loss benefit from creating an artificial valve, namely, nipple valve.

Impact on caregivers of adult patients receiving parenteral support for short-bowel syndrome with intestinal failure: A multinational, cross-sectional survey

Background

Patients with short‐bowel syndrome and intestinal failure (SBS‐IF) require parenteral support (PS) and may need long‐term home‐care support. This survey assessed the impact of care provision on adult caregivers of adult patients receiving PS for SBS‐IF.

Methods

An online, cross‐sectional survey of caregivers of adults with a self‐reported physician diagnosis of SBS‐IF was conducted in France, Germany, Italy, the UK, and USA. Impact on caregivers was evaluated using the 18‐item Caregiver Strain Index (CSI), the Work Productivity and Activity Impairment Questionnaire: Specific Health Problem (WPAI:SHP), and self‐reporting impact questionnaires.

Results

Caregivers (N = 121; aged 51 ± 13.7 years; 59% women) provided assistance for a mean of 9.9 ± 12.53 years; 77% were providing care 7 days per week. Patients (51 ± 16.4 years; 56% women) of caregivers were typically family members: spouse/partner (61%), adult son/daughter (19%), or parent (10%). Caregivers reported experiencing some strain (CSI score 4 ± 3.4). Among 71 of 73 employed caregivers, the WPAI:SHP assessment showed that caregivers missed 7% ± 12.7% of work hours in the preceding week and were present but not productive at work 37% ± 23.1% of the time; 28% of caregivers reported a reduced number of working hours because of caregiving. Many caregivers reported limitations in recreational activities (53%), and ≥30% had difficulty spending time with family and friends. Caregivers (87%) also reported worrying about the patient's health.

Conclusions

Caregivers of adult patients with SBS‐IF experience negative daily personal impacts and loss of productivity arising from their caregiving responsibilities.

Restricted v. unrestricted oral intake in high output end-jejunostomy patients referred to reconstructive surgery

The major complication of end jejunostomy is excessive fluid and electrolyte loss through the stoma, leading to hypovolaemia and dyselectrolytaemia within days and malnutrition within weeks. The aim was to compare the results of two nutritional approaches: unrestricted and restricted oral intake in patients with end jejunostomy commencing home parenteral nutrition (HPN) in terms of liver and renal biochemical markers and time to reconstructive bowel surgery with correlation to stoma output. Twenty patients with stabilised high output end-jejunostomy were divided into two groups. Group A consisted of ten patients with oral intake restricted to keep stomal output under 1000 ml. Group B consisted of ten patients with unrestricted oral intake. The following parameters were evaluated over 6 months: stomal output, self-estimation of general condition, body weight gain, plasma bilirubin and creatinine, number of hospitalisations prior to reconstructive surgery, the frequency of ostomy bag emptying, feelings of hunger and thirst in the daytime, and the time to reconstructive surgery. Stoma losses were compensated by parenteral supply. In group B, lower quality of life was observed, reflected by weakness, permanent feelings of hunger and thirst and the need for night-time emptying of the stoma bag. Patients in group B developed more complications and required more time to prepare for surgery. One death occurred in group B due to renal insufficiency followed by septic complications. Restricted oral intake seems to be more effective for prevention of HPN-related complications and shortening of time to surgery. Unrestricted oral intake appears to provoke uncontrolled losses of energy and protein, inhibiting weight gain.

Short bowel syndrome: treatment options

Introduction Short bowel syndrome (SBS) refers to the malabsorptive state that occurs following extensive intestinal resection and is associated with several complications.

Methods The research for this review was conducted in the Pubmed database. Relevant scientific articles dated between 1991 and 2015 and written in Portuguese, Spanish or English were selected.

Results Several therapies, including nutritional support, pharmacological options and surgical procedures have been used in these patients.

Conclusions Over the last decades new surgical and pharmacological approaches emerged, increasing survival and quality of life (QoL) in patients with SBS. All SBS patients ought to have an individualized and multidisciplinary care that promotes intestinal rehabilitation.

Intestinal adaptation following spring insertion into a roux limb in mice

BACKGROUND/PURPOSE

Intraluminal springs have recently been shown to lengthen segments of intestine in a process known as distraction enterogenesis. We hypothesized that biocompatible springs could be used to lengthen defunctionalized murine small intestine and would lead to identifiable intestinal adaptations at the molecular level.

METHODS

Age and weight matched C57BL/6 mice underwent surgical insertion of nitinol spring-loaded capsules into a Roux limb of jejunum. Segment lengths were measured at initial spring placement and at euthanasia after 14 and 21 days. Histology and gene expression of the Roux limb were evaluated at scarification and compared to untreated control segments.

RESULTS

Intestinal segments loaded with compressed springs lengthened an average of 240%, which was significantly longer than control segments loaded with either empty capsules or uncompressed springs. Muscularis thickening was greater in spring-treated mice compared to controls without springs. Crypt depth and Lgr5+ expression was greater in mice that received compressed spring treatments when compared to control groups.

CONCLUSIONS

Insertion of a compressed nitinol spring into a Roux limb results in significant intestinal lengthening, smooth muscle thickening, and Lgr5+ expression in a mouse model. The ability to increase small bowel length in a defunctionalized murine model may be used to understand the mechanism of distraction enterogenesis.

Long term outcomes of intestinal rehabilitation in children with neonatal very short bowel syndrome: Parenteral nutrition or intestinal transplantation

BACKGROUND & AIMS

Intestinal rehabilitation is the preferred treatment for children with short bowel syndrome (SBS) whatever the residual bowel length, and depends on the accurate management of long-term parenteral nutrition (PN). If nutritional failure develops, intestinal transplantation (ITx) should be discussed and may be life-saving. This study aimed to evaluate survival, PN dependency and nutritional status in children with neonatal very SBS on PN or after ITx, in order to define indications and timing of both treatments.

PATIENTS AND METHODS

This retrospective cross-sectional study enrolled 36 children with very SBS (<40 cm) who entered our intestinal rehabilitation program from 1987 to 2007.

RESULTS

All the children on long-term PN (n = 16) survived with a follow-up of 17 years (9-20). Six of them were eventually weaned off PN. Twenty children underwent ITx: eight children died (40%) 29 months (0-127) after Tx. The others 12 patients were weaned off PN 73 days (13-330) after Tx. Follow-up after transplantation was 14 years (6-28). Seven out of 8 (88%) patients with a history of gastroschisis required ITx. Patients who required ITx had longer stoma duration.

CONCLUSION

Survival rate of children with very short bowel was excellent if no life-threatening complications requiring transplantation developed. Gastroschisis and delayed ostomy closure are confirmed as risk factor for nutritional failure. Intestinal rehabilitation may allow a total weaning of PN before adulthood. A follow-up by a multidisciplinary team is necessary to avoid PN complications in order to minimize indications for ITx.

Strategies for early metabolic disturbances in patients with an end jejunostomy or end ileostomy. Experience from a specialized Home Parenteral Nutrition (HPN) center

INTRODUCTION

An end stoma syndrome is usually the result of an intentional surgical intervention in the course of staged treatment or a complication of surgery. These patients most frequently suffer from water and electrolyte disturbances, malnutrition syndromes caused by malabsorption of trace elements and/or vitamins, and undernutrition.

AIM

To present early metabolic disturbances observed in patients with an end jejunostomy or end ileostomy syndrome on the first day of their hospitalization in a specialist Home Parenteral Nutrition (HPN) center.

MATERIAL AND METHODS

The study included 142 patients with an end stoma syndrome (76 women and 66 men), hospitalized between 2004 and 2014. Patients were divided into two main groups. Group A consisted of 90 patients with an end jejunostomy and group B consisted of 52 patients with an end ileostomy.

RESULTS

After comparing the patients with an end jejunostomy vs. those with an end ileostomy, significant differences were found as regards pH (7.34 vs. 7.39, p = 0.043) and BE (3.24 vs. -0.86, p = 0.005). Depending on the lack or possibility of oral food intake, patients in the end jejunostomy group had different levels of the markers phosphate, Mg, Ca, urea, and creatinine, with all of these parameters within normal laboratory limits. When the end ileostomy group was divided into subgroups depending on the lack or possibility of oral food intake, differences in C-reactive protein activity were found (55.6 vs. 25.7, p = 0.041).

CONCLUSIONS

Patients with an end jejunostomy syndrome are more prone to metabolic acidosis with significant alkali deficiencies.

Principles and Strategies for Monitoring Home Parenteral Nutrition

Patients who cannot ingest adequate calories to maintain body weight via their gastrointestinal tract may require parenteral nutrition (PN) at home. As with any therapy, the patient must be evaluated to determine if the home PN (HPN) is effective and the patient is free of complications. This review discusses specific items to monitor for HPN patients. Parameters to monitor can be divided into those used to determine effectiveness and those used to prevent complications of HPN. In addition, potential HPN-associated complications can be divided into those that occur with short- or long-term PN administration. Specific items to monitor are discussed within this framework.

Complex, multi-scale small intestinal topography replicated in cellular growth substrates fabricated via chemical vapor deposition of Parylene C

Native small intestine possesses distinct multi-scale structures (e.g., crypts, villi) not included in traditional 2D intestinal culture models for drug delivery and regenerative medicine. The known impact of structure on cell function motivates exploration of the influence of intestinal topography on the phenotype of cultured epithelial cells, but the irregular, macro- to submicron-scale features of native intestine are challenging to precisely replicate in cellular growth substrates. Herein, we utilized chemical vapor deposition of Parylene C on decellularized porcine small intestine to create polymeric intestinal replicas containing biomimetic irregular, multi-scale structures. These replicas were used as molds for polydimethylsiloxane (PDMS) growth substrates with macro to submicron intestinal topographical features. Resultant PDMS replicas exhibit multiscale resolution including macro- to micro-scale folds, crypt and villus structures, and submicron-scale features of the underlying basement membrane. After 10 d of human epithelial colorectal cell culture on PDMS substrates, the inclusion of biomimetic topographical features enhanced alkaline phosphatase expression 2.3-fold compared to flat controls, suggesting biomimetic topography is important in induced epithelial differentiation. This work presents a facile, inexpensive method for precisely replicating complex hierarchal features of native tissue, towards a new model for regenerative medicine and drug delivery for intestinal disorders and diseases.

Teduglutide: a guide to its use in short bowel syndrome

Teduglutide (Gattex(®)) is a recombinant analogue of human glucagon-like peptide-2 and is indicated for the treatment of adults with short bowel syndrome (SBS) dependent on parenteral support (PS). In a pivotal, 24-week clinical trial in SBS patients, subcutaneous teduglutide 0.05 mg/kg once daily increased absorption from the remnant intestine as evidenced by significant reductions in PS volume requirements versus placebo. Improvements attained in absorption in the first 6 months of therapy were maintained during the extension trial (total teduglutide treatment periods of up to 30 months), with evidence indicating that benefits accrue over time. Among patients who received teduglutide treatment for up to 30 months, 11 of 30 were able to achieve at least one additional day off PS and another ten achieved complete independence from PS. Subcutaneous teduglutide was generally well tolerated in clinical trials, including over the long term, with most adverse events that led to study discontinuation being gastrointestinal in origin.

Factors affecting poor nutritional status after small bowel resection in patients with Crohn disease

In Crohn disease, bowel-preserving surgery is necessary to prevent short bowel syndrome due to repeated operations. This study aimed to determine the remnant small bowel length cut-off and to evaluate the clinical factors related to nutritional status after small bowel resection in Crohn disease.We included 394 patients (69.3% male) who underwent small bowel resection for Crohn disease between 1991 and 2012. Patients who were classified as underweight (body mass index < 17.5) or at high risk of nutrition-related problems (modified nutritional risk index < 83.5) were regarded as having a poor nutritional status. Preliminary remnant small bowel length cut-offs were determined using receiver operating characteristic curves. Variables associated with poor nutritional status were assessed retrospectively using Student t tests, chi-squared tests, Fisher exact tests, and logistic regression analyses.The mean follow-up period was 52.9 months and the mean patient ages at the time of the last bowel surgery and last follow-up were 31.2 and 35.7 years, respectively. The mean remnant small bowel length was 331.8 cm. Forty-three patients (10.9%) underwent ileostomy, 309 (78.4%) underwent combined small bowel and colon resection, 111 (28.2%) had currently active disease, and 105 (26.6%) underwent at least 2 operations for recurrent disease. The mean body mass index and modified nutritional risk index were 20.6 and 100.8, respectively. The independent factors affecting underweight status were remnant small bowel length ≤240 cm (odds ratio: 4.84, P < 0.001), ileostomy (odds ratio: 4.70, P < 0.001), and currently active disease (odds ratio: 4.16, P < 0.001). The independent factors affecting high nutritional risk were remnant small bowel length ≤230 cm (odds ratio: 2.84, P = 0.012), presence of ileostomy (odds ratio: 3.36, P = 0.025), and currently active disease (odds ratio: 4.90, P < 0.001).Currently active disease, ileostomy, and remnant small bowel length ≤230 cm are risk factors affecting the poor nutritional status of patients with Crohn disease after small bowel resection.

Intestinal Failure: Adaptation, Rehabilitation, and Transplantation

Intestinal failure (IF) is a state in which the nutritional demands are not met by the gastrointestinal absorptive surface. A majority of IF cases are associated with short-bowel syndrome, which is a result of malabsorption after significant intestinal resection for numerous reasons, some of which include Crohn's disease, vascular thrombosis, and radiation enteritis. IF can also be caused by obstruction, dysmotility, and congenital defects. Recognition and management of IF can be challenging, given the complex nature of this condition. This review discusses the management of IF with a focus on intestinal rehabilitation, parenteral nutrition, and transplantation.

Small Bowel Endoscopy

OPINION STATEMENT

The small bowel is a challenging area for endoscopic evaluation and therapy due to its length and angulated configuration. A small lumen diameter and segmental peristalsis made it a perfect fit for examination by a novel ingestible wireless camera in a capsule. The development of capsule endoscopy changed the diagnosis and management of bleeding lesions, ulcers, and tumors deep in the small bowel, allowing earlier diagnosis with excellent patient acceptance. Device-assisted enteroscopy revolutionized small bowel therapy, particularly management of bleeding, Peutz-Jeghers polyposis, and tumor marking for minimally invasive surgery. Small bowel stricture dilation in select patients is safe and effective. Tools for a spectrum of small bowel therapies are available but remain suboptimal to tackle lesions on angulated folds deep in the small bowel. Universal terminology to describe the endoscopic appearance of vascular lesions will facilitate studies of endoscopic and medical therapy. The future holds improvements in imaging, easier advancement through the small bowel, and therapeutic capacity. This review focuses on methods of small bowel endoscopy, therapy, and outcomes.

Acquired causes of intestinal malabsorption

This review focuses on the acquired causes, diagnosis, and treatment of intestinal malabsorption. Intestinal absorption is a complex process that depends on many variables, including the digestion of nutrients within the intestinal lumen, the absorptive surface of the small intestine, the membrane transport systems, and the epithelial absorptive enzymes. Acquired causes of malabsorption are classified by focussing on the three phases of digestion and absorption: 1) luminal/digestive phase, 2) mucosal/absorptive phase, and 3) transport phase. Most acquired diseases affect the luminal/digestive phase. These include short bowel syndrome, extensive small bowel inflammation, motility disorders, and deficiencies of digestive enzymes or bile salts. Diagnosis depends on symptoms, physical examination, and blood and stool tests. There is no gold standard for the diagnosis of malabsorption. Further testing should be based on the specific clinical context and the suspected underlying disease. Therapy is directed at nutritional support by enteral or parenteral feeding and screening for and supplementation of deficiencies in vitamins and minerals. Early enteral feeding is important for intestinal adaptation in short bowel syndrome. Medicinal treatment options for diarrhoea in malabsorption include loperamide, codeine, cholestyramine, or antibiotics.

Thrombolysis for Severe Intestinal Ischemia due to Midgut Volvulus in a Neonate

Intestinal malrotation complicated by the development of midgut volvulus presents a difficult management dilemma because of the risk of short bowel syndrome. Here, we present our experience with a case of severe intestinal ischemia after derotation in a newborn successfully managed using systemic tissue plasminogen activator. The present report supports the usefulness of thrombolysis as a therapeutic option for reperfusion of ischemic small bowel due to midgut volvulus in neonates.

The Fecal Microbiome in Pediatric Patients With Short Bowel Syndrome

BACKGROUND

Changes in the intestinal microbiome of patients with short bowel syndrome (SBS) are thought to significantly affect clinical outcome. These changes may not only delay enteral diet advancement but may also predispose patients to bacterial translocation, bacteremia, and liver disease. Patients with SBS are thought to be more susceptible to changes in gut microbial communities due to intestinal dysmotility and/or lack of anatomic safeguards such as the ileocecal valve.

MATERIALS AND METHODS

We analyzed the bacterial composition of 21 fecal specimens from 9 children with SBS and 8 healthy children ages 4 months to 8 years by 16S ribosomal RNA gene sequencing. The sequences were quality filtered and analyzed using QIIME, the Ribosomal Database Project Classifier, and the randomForest supervised learning algorithm.

RESULTS

The fecal microbiome of patients with SBS is different from that of healthy controls. Stool from patients with SBS had a significantly greater abundance of the bacterial classes Gammaproteobacteria and Bacilli. Stool from patients with SBS who experienced increased stool frequency tended to have increased abundance of Lactobacillus (P = .057) and decreased abundance of Ruminococcus.

CONCLUSION

This study shows that the fecal microbiome of patients with SBS is significantly different from that of healthy controls when analyzed by 16S metagenomics. Differences in the composition and function of gut microbiomes in children with SBS may affect bowel physiology, and these findings may provide new opportunities for intestinal rehabilitation and clinical management.

D-lactic acidosis: an underrecognized complication of short bowel syndrome

D-lactic acidosis or D-lactate encephalopathy is a rare condition that occurs primarily in individuals who have a history of short bowel syndrome. The unabsorbed carbohydrates act as a substrate for colonic bacteria to form D-lactic acid among other organic acids. The acidic pH generated as a result of D-lactate production further propagates production of D-lactic acid, hence giving rise to a vicious cycle. D-lactic acid accumulation in the blood can cause neurologic symptoms such as delirium, ataxia, and slurred speech. Diagnosis is made by a combination of clinical and laboratory data including special assays for D-lactate. Treatment includes correcting the acidosis and decreasing substrate for D-lactate such as carbohydrates in meals. In addition, antibiotics can be used to clear colonic flora. Although newer techniques for diagnosis and treatment are being developed, clinical diagnosis still holds paramount importance, as there can be many confounders in the diagnosis as will be discussed subsequently.

Improved tolerance for enteral nutrition after serial transverse enteroplasty (STEP) in infants and children with short bowel syndrome--a seven-year single-center experience

BACKGROUND

Serial transverse enteroplasty (STEP) was designed to lengthen and taper the small intestine in patients with short bowel syndrome (SBS) and dilated small bowel. We hypothesized that tolerance for enteral nutrition (EN) improves after STEP.

METHODS

Patients who underwent STEP between March 2004 and January 2011 were identified. Candidates for STEP had radiographic evidence of dilated small bowel and either failed to advance EN or demonstrated deterioration in tolerance for EN. Clinical and nutritional data were analyzed pre- and post-STEP. EN was defined as the percentage of calories administered enterally. Statistical analysis employed the signed rank test with significance assumed when p<0.05.

RESULTS

Twenty STEPs were performed at a median age of 13.7 months. Median pre-STEP bowel length was 30 cm with a median increase in bowel length of 42%. Five patients achieved enteral autonomy at a median of 6.5 months post-STEP. EN increased in 75%, while 25% exhibited unchanged or decreased EN post-STEP. In aggregate, median EN tolerance increased from 22% at one month pre-STEP to 61% at six months post-STEP (p=0.003).

CONCLUSIONS

The STEP is an effective adjunct in the treatment of patients with intestinal failure. While enteral autonomy is eventually possible in some patients, improved enteral tolerance can be achieved in a majority of cases.

Variability of resting energy expenditure in infants and young children with intestinal failure-associated liver disease

OBJECTIVE

The aim of the study was to determine, in a cohort of young children with intestinal failure (IF), whether the estimates of basal metabolic rate (BMR) by standard equations can approximate measured resting energy expenditure (REE) by indirect calorimetry (IC).

METHODS

IC was performed using the dilutional canopy technique. REE measurements were compared with standard, age-based estimation equations (World Health Organization) for BMR. Subjects were classified as hypermetabolic (REE > 110% BMR), hypometabolic (REE < 90% BMR), or normal (REE = 90%-110% BMR).

RESULTS

Twenty-eight IF patients (11 girls, 17 boys) had an underlying diagnosis of necrotizing enterocolitis (n = 10) or a congenital gastrointestinal defect (n = 18). Median age was 5.3 months. Median interquartile range (IQR) REE was 46 (42-58) kcal · kg · day. Median (IQR) total energy intake provided 209% (172%-257%) of REE, with parenteral nutrition providing 76% (23%) of total energy intake. REE was variable, with 39% (n = 11) of measurements hypermetabolic, 39% (n = 11) hypometabolic, and the remaining 21% (n = 6) normal. Although REE was well correlated with estimated BMR (r = 0.82, P < 0.0001), estimated BMR was not consistently an adequate predictor of REE. BMR over- or underestimated REE by >10 kcal · kg · day in 15 of 28 (54%) patients. REE was not significantly correlated with severity of liver disease, nutritional status, total energy intake, or gestational age.

CONCLUSIONS

Energy expenditure is variable among children with IF and IF-associated liver disease, with approximately 80% of our cohort exhibiting either hypo- or hypermetabolism. Standard estimation equations frequently do not correctly predict individual REE. Longitudinal studies of energy expenditure and body composition may be needed to guide provision of nutrition regimens.

Pathophysiology of short bowel syndrome: considerations of resected and residual anatomy

The human small intestine is organized with a proximal-to-distal gradient of mucosal structure and nutrient processing capacity. However, certain nutrients undergo site-specific digestion and absorption, such as iron and folate in the duodenum/jejunum vs vitamin B12 and bile salts in the ileum. Intestinal resection can result in short bowel syndrome (SBS) due to reduction of total and/or site-specific nutrient processing areas. Depending on the segment(s) of intestine resected, malabsorption can be nutrient specific (eg, vitamin B12 or fat) or sweeping, with deficiencies in energy, protein, and various micronutrients. Jejunal resections are generally better tolerated than ileal resections because of greater postresection adaptive capacity than that of the jejunum. Following intestinal resection, energy scavenging and fluid absorption become particularly important in the colon owing to loss of digestive and absorptive surface area in the resection portion. Resection-induced alterations in enteroendocrine cell abundance can further disrupt intestinal function. For example, patients with end jejunostomy have depressed circulating peptide YY and glucagon-like peptide 2 concentrations, which likely contribute to the rapid intestinal transit and blunted intestinal adaptation observed in this population. SBS-associated pathophysiology often extends beyond the gastrointestinal tract, with hepatobiliary disease, metabolic bone disease, D-lactic acidosis, and kidney stone formation being chronic complications. Clinical management of SBS must be individualized to account for the specific nutrient processing deficit within the remnant bowel and to mitigate potential complications, both inside and outside the gastrointestinal tract.

Neonatal intestinal physiology and failure

The neonatal intestine is a complex organ that regulates the absorption of nutrients essential for growth and development. Intestinal failure results from insufficient or functionally inadequate bowel and can lead to failure of neonatal growth and development. Current literature on neonatal intestinal physiology and failure was reviewed and summarized. A homeostatic interplay of electrolytes, enzymes, and hormonal regulators is essential to achieve the physiologic balance needed for adequate intestinal performance. Physiologic consequences of intestinal failure are dependent on the length and anatomic location of the diseased or surgically resected bowel. Intestinal failure leads to disruption of normal intestinal physiology and may have long-term consequences for growth and development if inadequately treated. Parenteral nutrition remains the mainstay of treatment for neonatal intestinal failure.

An Unusual Case of Stercoral Perforation in a Patient with 86 cm of Small Bowel

A 77-year-old male who previously had extensive enterectomy due to ischaemic gut with loss of all but 86 cm of jejunum in addition to a right hemicolectomy presented to the emergency department (ED) with abdominal pain and constipation of 12-day duration. Abdominal imaging with X-ray and CT revealed pneumoperitoneum in addition to a grossly redundant and faecally loaded colon. At laparotomy, rectal perforation was found. In view of the patient's advanced age, comorbidities, and the absence of intraperitoneal faecal contamination, manual disimpaction followed by wedge resection and primary closure of the perforation was done. On postop day 11, a perforation in the sigmoid colon with free subdiaphragmatic gas was picked up on CT after a work up for abdominal tenderness. In the absence of peritonism and other signs of deterioration, conservative management was chosen with subsequent uneventful recovery for the patient.

An overview of short bowel syndrome management: adherence, adaptation, and practical recommendations

Short bowel syndrome (SBS) refers to the clinical consequences resulting from loss of small bowel absorptive surface area due to surgical resection or bypass. The syndrome is characterized by maldigestion, malabsorption, and malnutrition. Survival of patients with SBS is dependent on adaptation in the remaining bowel and a combination of pharmacologic and nutrition therapies. Individual plans of care are developed based on the length and sites of remaining bowel, the degree of intestinal adaptation, and the patient's ability to adhere to the medication and dietary regimens. Antisecretory and antidiarrheal medications are prescribed to slow intestinal transit times and optimize fluid and nutrient absorption. Based on postsurgical anatomy, enteral feedings, parenteral infusions, complex diet plans, and vitamin and mineral supplementation are used in various combinations to nourish patients with SBS. In the acute care setting, registered dietitians (RDs) assist with infusion therapy, diet education, and discharge planning. Long-term, as the small intestine adapts, RDs revise the nutrition care plan and monitor for nutrient deficiencies, metabolic bone disease, and anemia. The frequent monitoring and revision of care plans, plus the appreciable benefits from proper medical nutrition therapy, make this patient population extremely challenging and rewarding for RDs to manage. This article provides a brief, case study-based overview of the medical and nutrition management of SBS.

Key issues in addressing the clinical and humanistic burden of short bowel syndrome in the US

BACKGROUND

The purpose of this analysis was to provide a concise report of the literature on the burden of intestinal failure associated with short bowel syndrome (SBS-IF) in adults, focused on clinical and humanistic issues important to clinicians and payers.

SCOPE

A literature search was performed using the National Library of Medicine PubMed database ( http://www.ncbi.nlm.nih.gov/pubmed ) with the search term 'short bowel syndrome' limited to adult populations and English-language reports published from January 1, 1965, to January 18, 2013. Citations were assessed for relevance and excluded articles focused on single case studies, colon fermentation, absorption of medications with PN/IV, surgical technique, mesenteric artery complications/surgery, and transplantation focus. Additional hand searches were performed using the terms 'short bowel syndrome' AND 'cost', and 'home parenteral nutrition' AND 'cost', along with the exclusion criteria described above.

FINDINGS

Despite advances in management in recent decades, SBS-IF continues to carry a high burden of morbidity and mortality. In the absence of sufficient intestinal adaptation following resection, many patients remain dependent on long-term parenteral nutrition and/or intravenous fluids (PN/IV). Although potentially life saving, PN/IV is costly, invasive, and associated with numerous complications and deleterious effects on health and quality of life. Surgical interventions, especially intestinal transplantation, are costly and are associated with substantial morbidity and high mortality. New therapies, which show promise in promoting intestinal rehabilitation and reducing dependence on PN/IV therapy, are the subject of active research.

CONCLUSIONS

Overall, the available literature suggests that although SBS-IF affects a relatively small population, the clinical and humanistic burden is significant, and there is an unmet need for effective therapeutic options that target the underlying problem of inadequate absorptive capacity of the remaining intestine. Consequently, many patients with SBS-IF remain dependent on long-term PN/IV support, adding to the burden imposed by the underlying disorder.

Regeneration of enteric ganglia in mechanically lengthened jejunum after restoration into intestinal continuity

PURPOSE

We previously demonstrated that it is feasible to lengthen intestinal segments with mechanical force and to restore them back into intestinal continuity. The changes in the enteric ganglia in the lengthened intestinal segments have not been described.

METHODS

A 1-cm segment of rodent jejunum was isolated from intestinal continuity and was lengthened using a spring. After lengthening, jejunal segments were either retrieved (n=4) or restored into intestinal continuity (n=4). Rats with restored segments were euthanized 2 to 3 weeks later. Ganglia were identified and quantified by immunostaining of histological sections.

RESULTS

The normal jejunum had 51 ± 5 myenteric and 31 ± 2 submucosal ganglia per circumferential tissue section. Lengthened segments had 21 ± 7 myenteric and 2 ± 2 submucosal ganglia. Restored segments had 46 ± 14 myenteric and 10 ± 10 submucosal ganglia. Circumferential density of ganglia followed a similar pattern.

CONCLUSION

Mechanical lengthening led to a paucity of submucosal and myenteric ganglia. After restoration into continuity, the number increased toward normal, indicating regeneration of the enteric ganglia. The function of regenerated ganglia needs to be assessed in the future.

Surgical management of Crohn's disease

Although medical management can control symptoms in a recurring incurable disease, such as Crohn's disease, surgical management is reserved for disease complications or those problems refractory to medical management. In this article, we cover general principles for the surgical management of Crohn's disease, ranging from skin tags, abscesses, fistulae, and stenoses to small bowel and extraintestinal disease.

Nutritional consequences of chronic diarrhoea

There is an undeniable link between gastrointestinal disorders and malnutrition. Chronic diarrhoea is one of the most common gastrointestinal conditions that can impact a patient's nutritional status. The nutritional consequences will depend on the cause of the diarrhoea as well as the location and extent of gastrointestinal involvement. In general, malabsorption plays a central role in the interaction between malnutrition and chronic diarrhoea. Malabsorption can result in both nutritional deficits and diarrhoea. With severe malnutrition, chronic diarrhoea can persist due to impaired immune function and poor mucosal recovery. Food intolerance and an inappropriate diet in the setting of malabsorption may also contribute to chronic diarrhoea. Patients may attribute their gastrointestinal symptoms to specific dietary intake, which can lead to self-imposed indiscriminate dietary restrictions. Therefore, disease-specific treatment in conjunction with appropriate nutritional counselling and intervention is recommended in the prevention and treatment of malnutrition in patients with chronic diarrhoea. Specialized nutritional support through enteral or parenteral administration may be required to treat severe caloric and micronutrient deficiencies. In this review, we aim to summarize the mechanism, diagnosis, and treatment of the nutritional consequences of chronic diarrhoea.

Enteral nutrients potentiate glucagon-like peptide-2 action and reduce dependence on parenteral nutrition in a rat model of human intestinal failure

Glucagon-like peptide-2 (GLP-2) is a nutrient-dependent, proglucagon-derived gut hormone that shows promise for the treatment of short bowel syndrome (SBS). Our objective was to investigate how combination GLP-2 + enteral nutrients (EN) affects intestinal adaption in a rat model that mimics severe human SBS and requires parenteral nutrition (PN). Male Sprague-Dawley rats were assigned to one of five groups and maintained with PN for 18 days: total parenteral nutrition (TPN) alone, TPN + GLP-2 (100 μg·kg(-1)·day(-1)), PN + EN + GLP-2(7 days), PN + EN + GLP-2(18 days), and a nonsurgical oral reference group. Animals underwent massive distal bowel resection followed by jejunocolic anastomosis and placement of jugular catheters. Starting on postoperative day 4, rats in the EN groups were allowed ad libitum access to EN. Groups provided PN + EN + GLP-2 had their rate of PN reduced by 0.25 ml/day starting on postoperative day 6. Groups provided PN + EN + GLP-2 demonstrated significantly greater body weight gain with similar energy intake and a safe 80% reduction in PN compared with TPN ± GLP-2. Groups provided PN + EN + GLP-2 for 7 or 18 days showed similar body weight gain, residual jejunal length, and digestive capacity. Groups provided PN + EN + GLP-2 showed increased jejunal GLP-2 receptor (GLP-2R), insulin-like growth factor-I (IGF-I), and IGF-binding protein-5 (IGFBP-5) expression. Treatment with TPN + GLP-2 demonstrated increased jejunal expression of epidermal growth factor. Cessation of GLP-2 after 7 days with continued EN sustained the majority of intestinal adaption and significantly increased expression of colonic proglucagon compared with PN + EN + GLP-2 for 18 days, and increased plasma GLP-2 concentrations compared with TPN alone. In summary, EN potentiate the intestinotrophic actions of GLP-2 by improving body weight gain allowing for a safe 80% reduction in PN with increased jejunal expression of GLP-2R, IGF-I, and IGFBP-5 following distal bowel resection in the rat.

Intestinal transplantation: a review

Parenteral nutrition is a life-saving therapy for patients with intestinal failure. Intestinal transplantation is now recognized as a treatment for patients who develop complications of parenteral nutrition and in whom attempts at intestinal rehabilitation have failed. Patients with parenteral nutrition related liver disease will require a liver graft typically part of a multivisceral transplant. Isolated intestinal transplants are more commonly performed in adults while multivisceral transplants are most commonly performed in infants. Isolated intestinal transplants have the best short-term outcome, with over 80 % survival at 1 year. Patients requiring multivisceral transplants have a high rate of attrition with a 1 year survival less than 70 %. Prognostic factors for a poor outcome include patient hospitalization at the time of transplant and donor age greater than 40 years while systemic sepsis and acute rejection are the major determinant of early postoperative outcome. For patients surviving the first year the outcome of transplantation of the liver in addition to intestine affords some survival advantage though long-term outcome does not yet match other abdominal organs. Outcomes for intestinal retransplantation are poor as a result of immunology and patient debility. Overall intestinal transplantation continues to develop and is a clear indication with cost and quality of life advantages in patients with intestinal failure that do not remain stable on parenteral nutrition.

Implementation of a multidisciplinary team approach and fish oil emulsion administration in the management of infants with short bowel syndrome and parenteral nutrition-associated liver disease

OBJECTIVE

To describe the authors' experience with the implementation of a multidisciplinary approach and use of fish oil emulsion (FOE) in the management of infants with short bowel syndrome (SBS) and parenteral nutrition-associated liver disease (PNALD).

METHODS

Between August 2006 and June 2009, four cases of SBS and severe PNALD were managed by the team using specifically developed protocols. The FOE was initiated if serum direct bilirubin levels were ≥100 µmol/L. To quantify the degree of exposure to high serum direct bilirubin levels over time, the area under the curve (AUC) for each patient was calculated before and after initiation of FOE. Linear regression analyses were performed to evaluate correlations between the AUC, duration of cholestasis and initiation of FOE.

RESULTS

All patients survived and no complications were observed during the study period. After the first patient, FOE was initiated progressively earlier, but poor correlation between the AUC before and after its introduction was observed (r(2)=0.41924). However, there was strong correlation between the duration of PNALD before FOE initiation and time to resolution (r(2)=0.72133): the earlier the FOE was initiated, the shorter the time to resolution.

CONCLUSION

The authors report a positive experience with the implementation of a multidisciplinary approach and the use of FOE in infants with SBS and severe PNALD. The earlier the FOE was initiated during the cholestatic process, the shorter the time to resolution. The present study is a hypothesis generator, raising the question of whether an earlier introduction of this particular therapy can effectively shorten the cholestasis process in these patients.

Vitamin K status in patients with short bowel syndrome

BACKGROUND & AIMS

Available evidence suggests that patients with short bowel syndrome (SBS) might be at risk of vitamins A, D, E and B(1) deficiency. However, there is little clinical data describing the vitamin K status. Therefore, in the present study we aimed to assess the body resources of vitamin K in a subset of SBS patients.

METHODS

The study comprised 33 patients aged 1 month to 16 years. PIVKA-II concentrations were determined in all subjects.

RESULTS

In all studied subjects, coagulation parameters were normal. PIVKA-II levels indicative of vitamin K deficiency was found in 3 (9.1%) SBS patients. One patient had been receiving an additional intravenous vitamin K dose of 5 mg/week. In all SBS patients with cirrhosis and cholestasis, PIVKA-II concentrations were low (<2 ng/ml). However, all patients with severe liver disease were receiving vitamin K several times a month.

CONCLUSIONS

Vitamin K deficiency may appear in SBS patients.