Short bowel syndrome and intestinal failure: consensus definitions and overview

Short bowel syndrome (SBS)-associated intestinal failure is a highly disabling condition that impairs quality of life and social integration. Although the condition is not uniformly fatal, it might lead to serious, life-threatening complications. The basic goals of medical treatment are to maintain fluid, electrolyte, and nutrient balances and to make appropriate modifications in disease management to avoid side effects. Various definitions have been proposed for SBS and intestinal failure within the medical literature, but many focus on different aspects of the conditions, leading to confusion. In the past, identifying the cause of intestinal failure was of little consequence, because all patients were managed on total parenteral nutrition at home. However, with the recent development of medical therapies such as recombinant growth hormone, octreotide, and glucagon-like peptide-2 analogues and with improvements in small bowel transplantation, many patients can be made nutritionally autonomous. To evaluate the relative efficacy of these therapies, there is now a need to develop consensus definitions so that patients can be properly categorized before therapy. To this end, a group of experts on the subject was convened to develop the following new definitions: "Intestinal failure results from obstruction, dysmotility, surgical resection, congenital defect, or disease-associated loss of absorption and is characterized by the inability to maintain protein-energy, fluid, electrolyte, or micronutrient balance." "Short-bowel syndrome results from surgical resection, congenital defect, or disease-associated loss of absorption and is characterized by the inability to maintain protein-energy, fluid, electrolyte, or micronutrient balances when on a conventionally accepted, normal diet."

Parenteral nutrition-associated liver disease and the role for isolated intestine and intestine/liver transplantation

Parenteral nutrition-associated liver disease (PNALD) is the most devastating complication of long-term parenteral nutrition therapy. Because its progression is typically insidious and its long-term consequences are generally underappreciated, PNALD is often recognized too late, when liver injury is irreversible. When end-stage liver disease (ESLD) develops in these patients, most potential interventions are futile and transplantation of both an intestine and a liver becomes the only viable option, despite the relatively poor outcomes associated with this combined procedure. Although likely multifactorial in origin, the etiology of PNALD is poorly understood. Early clinical intervention with a combination of nutritional, medical, hormonal, and surgical therapies can be effective in preventing liver disease progression. If these interventions fail, intestinal transplantation should be performed expeditiously before development of ESLD mandates simultaneous inclusion of a liver graft as well.

Intestinal Adaptation in Short Bowel Syndrome

Short bowel syndrome occurs when there is insufficient length of the small intestine to maintain adequate nutrition and/or hydration status without supplemental support. This syndrome most frequently occurs following extensive surgical resection of the intestine, and the extent of adaptation depends on the anatomy of the resected bowel and the amount of bowel remaining. Following resection, the intestinal tissue undergoes morphologic and functional changes to compensate for the lost function of the resected bowel. These changes are mediated by multiple interactive factors, including intraluminal and parenteral nutrients, gastrointestinal secretions, hormones, cytokines, and growth factors, many of which have been well characterized in animal models. The amount of small bowel remaining is the most important predictor of adaptive potential; neither structural nor functional adaptative changes have been demonstrated in humans or animal models with more extreme resections resulting in an end-jejunostomy. The current understanding of these processes has led to the recent use of supplemental hormones, such as growth hormone and glucagon-like peptide 2, in intestinal rehabilitation programs and may lead to the development of pharmacologic agents designed to augment the innate adaptive response.

A higher dose requirement of tacrolimus in active Crohn's disease may be related to a high intestinal P-glycoprotein content

Tacrolimus, a relatively new therapeutic option for patients with corticosteroid-refractory Crohn's disease or ulcerative colitis, is a substrate for the apically directed efflux transporter P-glycoprotein (P-gp). Duodenal biopsy specimens obtained from a patient with corticosteroid-refractory Crohn's disease and with significantly higher-than-average tacrolimus dose requirements were analyzed for P-gp by Western blot. The P-gp content in this patient was more than double that in specimens obtained from 9 of 10 healthy subjects. Elevated intestinal P-gp could have resulted in decreased tacrolimus absorption, thereby leading to decreased blood concentration and decreased efficacy in this patient. The cause and prevalence of this phenomenon are unknown.

Advances in the management of short bowel syndrome

Short bowel syndrome (SBS) is the predominant cause of intestinal failure and is thus associated with a high degree of morbidity and mortality. One of the reasons this occurs is the dramatic reduction in nutrient absorptive capacity. Of the many causes of SBS, the most common cause is extensive surgical resection. The impressive ability of the bowel to adapt functionally and morphologically is critical for decreasing morbidity and mortality in these patients. The degree of adaptation is vital in decreasing the dependence on parenteral nutrition (PN) and for improving patient quality of life and long-term outcome. Provision of appropriate and sufficient nutritional and fluid support is essential for the management of these patients. The primary goal is to prevent or eliminate the need for PN. Recent developments have promoted a greater understanding of the process of intestinal adaptation. Various intestinal trophic factors have been recognized. These efforts have led to the early development of hormonal therapy to stimulate intestinal adaptation and enhance intestinal absorption. Intestinal transplantation remains an option for those who have developed life-threatening complications from PN and cannot be managed using more conservative techniques.

The education and employment status of patients with inflammatory bowel diseases

Inflammatory bowel disease (IBD) has the propensity to affect patients who are in their late teens and early 20s, an age when most people decide on their educational and career directions. This review describes the effects that IBD has on the continuum of education and employment. Patients with Crohn's disease and ulcerative colitis attain a similar level of education as that of the general population. The quality of life of such patients in school, as measured by both patients' and teachers' perceptions, indicates that, despite the difficulties that students face in terms of missed school time and physical inconveniences, teachers are generally perceived by students to have favorable attitudes toward helping them. Even though earlier work in the area of employment has suggested that the occurrence of IBD is clustered among people in white-collar positions, recent data have suggested that certain environmental risks for IBD (i.e., sedentary or indoor jobs) may be associated with jobs classified as being white-collar, and therefore having a white-collar job may in itself not be a risk factor for the development of IBD. Patients with IBD have a higher rate of nonparticipation in the labor force, and the participation rate seems to maintain steady levels over time. A majority of patients with IBD continue in the same employment positions over a period of years. Patients with IBD, especially those who have undergone surgery, took more sick leave than their counterparts without IBD. A majority of patients with IBD favored the disclosure of their diagnosis to their employers and perceived little discrimination in the workplace. Furthermore, most employers were perceived by their employees with IBD as having fair attitudes toward the compensation provided for their employees with IBD.

Videocapsule endoscopy versus barium contrast studies for the diagnosis of Crohn's disease recurrence involving the small intestine

OBJECTIVES

Historically, suspected Crohn's disease (CD) has been evaluated with small bowel follow-through (SBFT) or enteroclysis (equally accurate). This study was undertaken to determine the accuracy of videocapsule endoscopy (VCE) in the diagnosis of CD relative to SBFT and clinical/laboratory indices of CD activity. Previous investigations have used VCE for the diagnosis of suspected CD in patients presenting with a variety of gastrointestinal symptoms. This is the first study to evaluate the occurrence of active disease in patients with known CD.

METHODS

Thirty subjects (22 female, 8 male, aged 36.9 +/- 14.2 yr); all with prior CD diagnosis made on the basis of standard criteria (5.5 +/- 6.5 yr prior to study), in whom recurrent CD was suspected based on abdominal pain, diarrhea, anemia, and/or arthralgias. Subjects were studied in a prospective, blinded evaluation of VCE versus SBFT. SBFT was performed first; those with stricture and proximal bowel dilation were excluded from further study. For SBFT, studies were graded as grade 0 (normal), grade 1 (minimal nodularity, ulcerations, normal luminal diameter, < 5 cm involved), grade 2 (more extensive ulcers, minimal luminal narrowing, 5-10 cm involved), or grade 3 (fistula, skip areas, extensive ulceration, >10 cm involved). VCE was performed within 1 wk of SBFT. Serum was obtained for ESR (erythrocyte sedimentation rate) and CRP (C-reactive protein), stool was obtained for alpha-1 antitrypsin, and the Harvey Bradshaw index of CD severity was calculated. VCE (digitalized video) was graded as grade 0 (normal), grade 1 (erythema, isolated villi loss), grade 2 (erosion, no ulcer), or grade 3 (ulcers, spontaneous bleeding, and/or stricture).

RESULTS

Twelve patients were excluded for small bowel obstruction. VCE and SBFT scores highly correlated (r = 0.65; p= 0.001). Active CD was visualized in 21 of 30 patients with videocapsule endoscopy and in 20 of 30 patients with SBFT. Complete agreement occurred in 13 of 30 studies; 13 of 17 studies differed by one grade. SBFT found mucosal disease in 20 of 30 patients and VCE found mucosal disease in 21 of 30 patients. VCE found mucosal disease in 6 patients (5 in grade 1, 1 in grade 3) with normal SBFT. SBFT showed CD in 5 patients (all grade 1) with normal VCE. Neither VCE nor SBFT scores correlated with biological or clinical indices. Patient satisfaction was superior for VCE.

CONCLUSIONS

VCE and SBFT are complementary for the diagnosis of CD. SBFT may be required to detect strictures as the videocapsule may not pass. However, some strictures may also be missed with SBFT. VCE is less invasive, less time-consuming for the patient than SBFT, and avoids radiation exposure, although reading time is greater for the gastroenterologist than the radiologist. Given that patients with clinically suspected CD recurrence may not have active disease, unnecessary and potentially harmful empiric therapy is not warranted without imaging.

The nutritional management of short bowel syndrome

Short bowel syndrome (SBS) is the predominant cause of intestinal failure and is associated with a high degree of morbidity and mortality. One of the reasons this occurs is because of the dramatic reduction in nutrient absorptive capacity. There are many causes for the development of SBS, but the most common is extensive surgical resection. The bowel has an impressive ability to adapt both morphologically and functionally. This adaptation becomes critical in decreasing morbidity and mortality. It is also critical for the improvement of quality of life and long-term outcomes. Provision of sufficient nutritional and fluid support is essential to the management of SBS patients. The primary goal is to prevent or eliminate the need for total parenteral nutrition. Specific diets and hormonal therapy may enhance the adaptation process depending on the characteristics of the remaining bowel. For those patients who experience both intestinal failure and life-threatening complications from total parenteral nutrition, bowel transplantation may be indicated.

Strictures from Crohn's disease diagnosed by video capsule endoscopy

Video capsule endoscopy is a new diagnostic modality that allows imaging of the entire small intestine. We report on a patient with a presumed but undocumented case of Crohn's disease who was found to have 9 ileal strictures by video capsule endoscopy. These strictures were undetected by small intestinal contrast studies and required surgical intervention. This case report suggests that small bowel radiographic studies may not be as sensitive for the detection of clinically significant luminal lesions as once thought.

Videocapsule endoscopy renders obscure gastrointestinal bleeding no longer obscure

INTRODUCTION

Hemorrhage arising from inaccessible areas of the gastrointestinal tract has long been an enigma in gastroenterology. The advent of the Given M2A videocapsule endoscope now permits direct visualization of small bowel mucosa. The purpose of this study is to compare the diagnostic yield of the Given M2A videocapsule endoscope to conventional push enteroscopy.

METHODS

Twenty consecutively referred patients (9 men aged 54.8 +/- 21.7 years, 11 women aged 65.6 +/- 16.6 years) who had previously had 1.6 +/- 0.8 EGDs, 1.6 +/- 0.8 colonoscopies, at least 1 normal small bowel radiographic study, and who had received 6.2 +/- 3.9 units of blood were studied. Patients underwent videocapsule endoscopy and subsequently push enteroscopy within 1 week. The endoscopist was blinded to the results of the videocapsule study.

RESULTS

Videocapsule endoscopy determined the source of bleeding in 12/20 (60%) of patients versus 15% for push enteroscopy (McNemara chi2, P = 0.02). Videocapsule endoscopy found a source of bleeding in 9/13 patients in whom enteroscopy was negative. Three patients had surgical resections for vascular ectasias (2) and a hamartoma (1) based on the videocapsule endoscopy results.

CONCLUSION

The Given M2A videocapsule endoscope has superior diagnostic utility for the evaluation of gastrointestinal bleeding when compared with standard push enteroscopy. The Given M2A videocapsule endoscope can be used to direct appropriate therapy in addition to avoiding the use of unnecessary conventional endoscopic and radiologic procedures.

Sjogren's syndrome in association with Crohn's disease

Crohn's disease has many autoimmune extraintestinal manifestations, such as arthritis, polymyositis, and erythema nodosum. However, an association between Crohn's disease and Sjogren's syndrome, an autoimmune disease, has rarely been reported. We describe the fourth case of Sjogren's syndrome in association with Crohn's disease. The patient is a 43-year-old African-American female diagnosed with Crohn's disease in 1981. Twenty years later, she developed abdominal pain, arthralgias, and sicca symptoms. Further evaluation led to a diagnosis of Sjogren's syndrome. Sjogren's syndrome should be considered in patients with underlying Crohn's disease who develop a constellation of constitutional, joint, and sicca symptoms.