Effect of intravenous ranitidine and omeprazole on intestinal absorption of water, sodium, and macronutrients in patients with intestinal resection

A review of enteral strategies in infant short bowel syndrome: evidence-based or NICU culture?

INTRODUCTION

Short bowel syndrome (SBS) is an increasingly common condition encountered across neonatal intensive care units. Improvements in parenteral nutrition (PN), neonatal intensive care and surgical techniques, in addition to an improved understanding of SBS pathophysiology, have contributed in equal parts to the survival of this fragile subset of infants. Prevention of intestinal failure associated liver disease (IFALD) and promotion of intestinal adaptation are primary goals of all involved in the care of these patients. While enteral nutritional and pharmacological strategies are necessary to achieve these goals, there remains great variability in the application of therapeutic strategies in units that are not necessarily evidence-based.

MATERIALS AND METHODS

A search of major English language medical databases (SCOPUS, Index Medicus, Medline, and the Cochrane database) was conducted for the key words short bowel syndrome, medical management, nutritional management and intestinal adaptation. All pharmacological and nutritional agents encountered in the literature search were classified based on their effects on absorptive capacity, intestinal adaptation and bowel motility that are the three major strategies employed in the management of SBS. The Oxford Center for Evidence-Based Medicine (CEBM) classification for levels of evidence was used to develop grades of clinical recommendation for each variable studied.

RESULTS

We reviewed various medications used and nutritional strategies included soluble fiber, enteral fat, glutamine, probiotics and sodium supplementation. Most interventions have scientific rationale but little evidence to support their role in the management of infant SBS. While some of these agents symptomatically improve diarrhea, they can adversely influence pancreatico-biliary function or actually impair intestinal adaptation. Surgical anatomy and liver function are two important variables that should determine the selection of pharmacological and nutritional interventions.

DISCUSSION

There is a paucity of research investigating optimal clinical practice in infant SBS and the little evidence available is consistently of lower quality, resulting in a wide variation of clinical practices among NICUs. Prospective trials should be encouraged to bridge the evidence gap between research and clinical practice to promote further progress in the field.

Acute effects of continuous infusions of glucagon-like peptide (GLP)-1, GLP-2 and the combination (GLP-1+GLP-2) on intestinal absorption in short bowel syndrome (SBS) patients. A placebo-controlled study

BACKGROUND AND AIMS

The ileocolonic brake is impaired in short bowel syndrome (SBS) patients with distal bowel resections. An attenuated meal-stimulated hormone secretion may cause gastric hypersecretion, rapid gastric and intestinal transit and a poor adaptation. Attempting to restore this ileocolonic brake, this study evaluated the acute effects of continuous intravenous administration of glucagon-like peptide (GLP) 1 and 2, alone or in combination, on gastrointestinal function in SBS patients.

METHODS

SBS patients were admitted 4 times for identical 72-h balance studies, where infusions (1 pmol/kg/min) of GLP-1, placebo (saline), GLP-2 and GLP-1+2 (1 pmol/kg/min of each), were provided. Patients filled out a VAS questionnaire regarding subjective symptoms during treatments. Bone mineral content, body-weight and -composition were measured using DEXA scans. Blood glucose, insulin, pro insulin C-peptide and GLP concentrations were measured in relation to a standardized breakfast.

RESULTS

Nine SBS patients (5 women/4 men, aged 52±11) were enrolled and completed the study; 7 had end-jejunostomies, 2 had 50% of colon-in-continuity. All treatments significantly reduced the fecal wet weight, energy, nitrogen, sodium and potassium losses compared to placebo. However, only GLP-2 containing treatments increased absolute absorption of wet weight and sodium. Only GLP-1+2 improved the hydrational status evaluated by DEXA increases in the fat mass and calculated total body weight. GLP-1 and GLP-1+2 reduced the post-prandial blood glucose levels. A tendency of nausea and reduced appetite was seen in relation to GLP-1 treatment, but this was ameliorated by the co-administration of GLP-2.

CONCLUSION

GLP-1 decreased diarrhea and fecal excretions in SBS patients, but it seems less potent than GLP-2. The combination of GLP-1+2 numerically provided additive effects on intestinal absorption compared to either peptide given alone. Larger, long-term studies should further assess the potential of the glucagon-like peptides or analogs, alone or in combination, in the treatment of SBS patients.

Management and complications of stomas

Stomas are created for a wide range of indications such as temporary protection of a high-risk anastomosis, diversion of sepsis, or permanent relief of obstructed defecation or incontinence. Yet this seemingly benign procedure is associated with an overall complication rate of up to 70%. Therefore, surgeons caring for patients with gastrointestinal diseases must be proficient not only with stoma creation but also with managing postoperative stoma-related complications. This article reviews the common complications associated with ostomy creation and strategies for their management.

Randomised controlled trial of colostrum to improve intestinal function in patients with short bowel syndrome

BACKGROUND/OBJECTIVES

Colostrum is rich in immunoregulatory, antimicrobial and trophic components supporting intestinal development and function in newborns. We assessed whether bovine colostrum could enhance intestinal adaptation and function in adult short bowel syndrome (SBS) patients.

SUBJECTS/METHODS

Twelve SBS patients in this randomised cross-over study received 4 weeks oral supplement of bovine colostrum or an iso-energetic and iso-proteinaceous control (2.4 MJ/d, 500 ml/day) separated by a 4-week washout period. Patients were admitted four times for 72-h periods of fluid, electrolyte and nutrient balance studies. Meals, faeces and urine were weighed, and energy, macronutrient and electrolyte contents were analysed to calculate net nutrient uptake. Body composition was measured by dual-energy X-ray absorptiometry scans, and functional tests of handgrip strength and lung functions were performed. Eight patients completed the study and were included in the analysis.

RESULTS

Both supplements (colostrum and control) not only increased protein (0.96 ± 0.42 MJ/d, P=0.004 1.03 ± 0.44 MJ/d, P=0.003) and energy (1.46 ± 1.02 MJ/d, P=0.005, 1.76 ± 1.46 MJ/d, P=0.01) absorption but also absolute faecal wet weight excretions (231 ± 248 g/d, P=0.002, 319 ± 299 g/d, P=0.03), compared with baseline measurements. Both supplements improved handgrip strength (P=0.03) while only the control supplement increased lean body mass (1.12 ± 1.33 kg, P<0.049). Colostrum was not found to be superior to the control.

CONCLUSION

Intake of high-protein milk supplements increased net nutrient absorption for adult SBS patients, but at the expense of increased diarrhoea. Despite high contents of bioactive factors, colostrum did not significantly improve intestinal absorption, body composition or functional tests compared with the control.

Teduglutide, a novel glucagon-like peptide 2 analog, in the treatment of patients with short bowel syndrome

Short bowel syndrome results from surgical resection, congenital defect or disease-associated loss of absorption. Parenteral support (PS) is lifesaving in patients with short bowel syndrome and intestinal failure who are unable to compensate for their malabsorption by metabolic or pharmacologic adaptation. Together, the symptoms of short bowel syndrome and the inconvenience and complications in relation to PS (e.g. catheter-related blood steam infections, central thrombosis and intestinal failure associated liver disease) may impair the quality of life of patients. The aim of treatment is to maximize intestinal absorption, minimize the inconvenience of diarrhea, and avoid, reduce or eliminate the need for PS to achieve the best possible quality of life for the patient. Conventional treatments include dietary manipulations, oral rehydration solutions, and antidiarrheal and antisecretory treatments. However, the evidence base for these interventions is limited and treatments that improve the structural and functional integrity of the remaining intestine are needed. Teduglutide, an analog of glucagon-like peptide 2, improves intestinal rehabilitation by promoting mucosal growth and possibly by restoring gastric emptying and secretion, thereby reducing intestinal losses and promoting intestinal absorption. In a 3-week, phase II balance study, teduglutide reduced diarrhea by around 700 g/day and fecal energy losses by around 0.8 MJ/day. In two randomized, placebo-controlled, 24-week, phase III studies, similar findings were obtained when evaluating the fluid composite effect, which is the sum of the beneficial effects of teduglutide - reduction in the need for PS, increase in urine production and reduction in oral fluid intake. The fluid composite effect reflects the increase in intestinal fluid absorption (and the concomitant reduction in diarrhea) and may be used in studies in which metabolic balance assessments are not performed. In studies of up to 24 weeks' duration, teduglutide appears to be safe and well tolerated. Treatment with teduglutide was associated with enhancement or restoration of the structural and functional integrity of the remaining intestine with significant intestinotrophic and proabsorptive effects, facilitating a reduction in diarrhea and an equivalent reduction in the need for PS in patients with short bowel syndrome and intestinal failure.

Treatment of adult short bowel syndrome patients with teduglutide

INTRODUCTION

Parenteral support is lifesaving in short bowel syndrome patients with intestinal failure (SBS-IF), who are unable to compensate for their malabsorption by metabolic or pharmacologic adaptation. Mutually, the symptoms of SBS-IF and the inconveniences and complications in relation to parenteral support may cause impairment of the quality of life of SBS-IF patients. Conventional treatments include dietary manipulations, oral rehydration solutions, antidiarrheal and antisecretory treatments. However, the evidence base for these interventions is limited, and treatments improving structural and functional integrity of the remaining intestine are desired. Teduglutide , an analog of glucagon-like peptide 2, improves intestinal rehabilitation by promoting mucosal growth and possibly by inhibiting gastric emptying and secretion, which in turn reduces intestinal losses and promotes intestinal absorption.

AREAS COVERED

This paper reviews the following findings: in a 3-week, Phase II balance study, teduglutide reduced diarrhea by ∼ 700 g/day and fecal energy losses by ∼ 0.8 MJ/day, and in a randomized, placebo-controlled, 24-week, Phase III study, corresponding reductions in the need for parenteral support were obtained.

EXPERT OPINION

Teduglutide seems to be safe and well-tolerated and demonstrates restoration of structural and functional integrity of the remaining intestine with significant intestinotrophic and proabsorptive effects, facilitating a reduction in diarrhea and an equivalent reduction in the need for parenteral support in SBS-IF patients.

Complications of enterocutaneous fistulas and their management

Complications related to enterocutaneous fistulas are common and include sepsis, malnutrition, and fluid or electrolyte abnormalities. Intestinal failure is one of the most feared complications of enterocutaneous fistula management and results in significant patient morbidity and mortality. The authors review emerging trends in the medical and surgical management of patients with intestinal failure.

Approaches to intestinal failure in Crohn's disease

Crohn's disease is one of the leading causes of intestinal failure. The term ‘type 2’ intestinal failure is used to describe the relatively rare type of intestinal failure that occurs in association with septic, metabolic and complex nutritional complications, typically following surgical resection and/or laparostomy for intra-abdominal sepsis. A multidisciplinary approach to the management of patients with type 2 intestinal failure is crucial, and it is helpful to approach patient care in a structured manner using the ‘sepsis-nutrition-anatomy-plan’ algorithm: resolution ofsepsis is required before adequate nutritional repletion can be achieved, and it is crucial to optimise nutritional status, and define intestinal anatomy before delineating a definitive medical or surgical plan. A structured approach to the management of patients with inflammatory bowel disease, who have developed type 2 intestinal failure, should reduce the likelihood of these patients developing ‘type 3’ intestinal failure, which is characterised by the need for long-term parenteral nutrition. However, Crohn's disease is still the commonest indication for home parenteral nutrition in the UK.

Proton pump inhibitors and severe hypomagnesaemia

PURPOSE OF REVIEW

Hypomagnesaemia has recently been recognized as a rare, but severe, complication of proton pump inhibitor (PPI) use. We reviewed all the cases published to date in peer-reviewed journals to summarize what is known of the epidemiology, risk factors, cause and treatment.

RECENT FINDINGS

Hypomagnesaemia has been described with all substituted pyridylmethylsulphonyl benzimidazadole derivatives and is a class effect, recurring with substitution of one PPI for another. A long duration of use and high rates of adherence are probably risk factors, but the prevalence is unknown. The diagnosis is often missed, despite the severe symptomatology. Renal magnesium handling is normal, so implicating impairment of net intestinal absorption as the proximate cause. It is not known whether this is the consequence of defective absorption of magnesium through the active or passive transport processes, or increased losses.

SUMMARY

PPI-associated hypomagnesaemia is a rare, but potentially life-threatening, side-effect that has emerged only in the era of mass use of these agents. The cause of hypomagnesaemia remains poorly understood, but it responds rapidly to withdrawal of the PPI.

Causes and management of a high-output stoma

AIM

Patients with a high-output stoma (HOS) (> 2000 ml/day) suffer from dehydration, hypomagnesaemia and under-nutrition. This study aimed to determine the incidence, aetiology and outcome of HOS.

METHOD

The number of stomas fashioned between 2002 and 2006 was determined. An early HOS was defined as occurring in hospital within 3 weeks of stoma formation and a late HOS was defined as occurring after discharge.

RESULTS

Six-hundred and eighty seven stomas were fashioned (456 ileostomy/jejunostomy and 231 colostomy). An early HOS occurred in 75 (16%) ileostomies/jejunostomies. Formation of a jejunostomy (defined as having less than 200 cm remaining of proximal small bowel; n = 20) and intra-abdominal sepsis? obstruction (n = 14) were the commonest causes identified for early HOS. It was possible to stop parenteral infusions in 53 (71%) patients treated with oral hypotonic fluid restriction, glucose-saline solution and anti diarrhoeal medication. In 46 (61%) patients, the HOS resolved and no drug treatment was needed, 20 (27%) patients continued treatment, six (8%) of whom went home and continued to receive parenteral or subcutaneous saline, and nine died. Twenty-six patients had late HOS. Eleven were admitted with renal impairment and four had intermittent small-bowel obstruction. Eight patients were given long-term subcutaneous or parenteral saline and two also received parenteral nutrition. All had hypomagnesaemia.

CONCLUSION

Early high output from an ileostomy is common and although 49% resolved spontaneously, 51% needed ongoing medical treatment, usually because of a short small-bowel remnant.

Short bowel syndrome

The short bowel syndrome (SBS) is a state of malabsorption following intestinal resection where there is less than 200 cm of intestinal length. The management of short bowel syndrome can be challenging and is best managed by a specialised multidisciplinary team. A good understanding of the pathophysiological consequences of resection of different portions of the small intestine is necessary to anticipate and prevent, where possible, consequences of SBS. Nutrient absorption and fluid and electrolyte management in the initial stages are critical to stabilisation of the patient and to facilitate the process of adaptation. Pharmacological adjuncts to promote adaptation are in the early stages of development. Primary restoration of bowel continuity, if possible, is the principle mode of surgical treatment. Surgical procedures to increase the surface area of the small intestine or improve its function may be of benefit in experienced hands, particularly in the paediatric population. Intestinal transplant is indicated at present for patients who have failed to tolerate long-term parenteral nutrition but with increasing experience, there may be a potentially expanded role for its use in the future.

Severe metabolic alkalosis and recurrent acute on chronic kidney injury in a patient with Crohn's disease

Background

Diarrhea is common in patients with Crohn's disease and may be accompanied by acid base disorders, most commonly metabolic acidosis due to intestinal loss of bicarbonate.

Case Presentation

Here, we present a case of severe metabolic alkalosis in a young patient suffering from M. Crohn. The patient had undergone multiple resections of the intestine and suffered from chronic kidney disease. He was now referred to our clinic for recurrent acute kidney injury, the nature of which was pre-renal due to profound volume depletion. Renal failure was associated with marked hypochloremic metabolic alkalosis which only responded to high volume repletion and high dose blockade of gastric hypersecretion. Intestinal failure with stomal fluid losses of up to 5.7 litres per day required port implantation to commence parenteral nutrition. Fluid and electrolyte replacement rapidly improved renal function and acid base homeostasis.

Conclusions

This case highlights the important role of gastrointestinal function to maintain acid base status in patients with Crohn's disease.

A case series of proton pump inhibitor-induced hypomagnesemia

Proton pump inhibitor (PPI)-induced hypomagnesemia has been recognized since 2006. Our aim was to further characterize the clinical consequences and possible mechanisms of this electrolyte disorder using 4 cases. Two men (aged 63 and 81 years) and 2 women (aged 73 and 62 years) had been using a PPI (esomeprazole, pantoprazole, omeprazole, and rabeprazole, 20-40 mg) for 1-13 years. They developed severe hypomagnesemia (magnesium, 0.30 +/- 0.28 mEq/L; reference, 1.40-2.10 mEq/L) with hypocalcemia (calcium, 6.4 +/- 1.8 mg/dL), relative hypoparathyroidism (parathyroid hormone, 43 +/- 6 pg/mL), and extremely low urinary calcium and magnesium excretion. One patient was admitted with postanoxic encephalopathy after a collapse likely caused by arrhythmia. The others had electrocardiogram abnormalities (prolonged QT interval, ST depression, and U waves). Concomitant hypokalemia (potassium, 2.8 +/- 0.1 mEq/L) was considered the trigger for these arrhythmias. Hypomagnesemia-induced kaliuresis (potassium excretion, 65 +/- 24 mEq/L) was identified as the cause of hypokalemia. This series of PPI-induced hypomagnesemia shows that this is a generic effect. It also indicates that hypomagnesemia may occur within 1 year of PPI therapy initiation and can have serious clinical consequences, likely triggered by the associated hypokalemia. A high index of suspicion is required in PPI users for unexplained hypomagnesemia, hypocalcemia, hypokalemia, or associated symptoms.

Short bowel patients treated for two years with glucagon-like Peptide 2: effects on intestinal morphology and absorption, renal function, bone and body composition, and muscle function

BACKGROUND AND AIMS

In a short-term study, Glucagon-like peptide 2 (GLP-2) has been shown to improve intestinal absorption in short bowel syndrome (SBS) patients. This study describes longitudinal changes in relation to GLP-2 treatment for two years.

METHODS

GLP-2, 400 micrograms, s.c.,TID, were offered, to eleven SBS patients keeping parenteral support constant. 72-hour nutritional balance studies were performed at baseline, weeks 13, 26, 52 during two years intermitted by an 8-week washout period. In addition, mucosal morphometrics, renal function (by creatinine clearance), body composition and bone mineral density (by DEXA), biochemical markers of bone turnover (by s-CTX and osteocalcin, PTH and vitamin D), and muscle function (NMR, lungfunction, exercise test) were measured.

RESULTS

GLP-2 compliance was >93%. Three of eleven patients did not complete the study. In the remaining 8 patients, GLP-2 significantly reduced the fecal wet weight from approximately 3.0 to approximately 2.0 kg/day. This was accompanied by a decline in the oral wet weight intake, maintaining intestinal wet weight absorption and urinary weight constant. Renal function improved. No significant changes were demonstrated in energy intake or absorption, and GLP-2 did not significantly affect mucosal morphology, body composition, bone mineral density or muscle function.

CONCLUSIONS

GLP-2 treatment reduces fecal weight by approximately 1000 g/d and enables SBS patients to maintain their intestinal fluid and electrolyte absorption at lower oral intakes. This was accompanied by a 28% improvement in creatinine clearance.

Role of the colon in short bowel syndrome and intestinal transplantation

Colon is a crucial partner for small intestinal adaptation and function in patients who underwent extensive small intestinal resection or transplantation. This short review deals with the different properties and roles of the colon in these settings, involving fluid and electrolytes absorption, absorption of medium-chain triglycerides, and production of short-chain fatty acids for malabsorbed energy salvage. The colon may adapt after small intestinal resection, whereas it hosts the most important part of the intestinal microbiota, which plays a crucial role in intestinal function and health. Also, colon may be responsible for D-lactic acidosis as well, as it can be injured by noninfectious colitis. Finally, the relevance of a simultaneous colon grafting is discussed as it is occasionally considered in specific patients requiring intestinal transplantation.

Severe hypomagnesaemia in long-term users of proton-pump inhibitors

OBJECTIVE

To explore the mechanism underlying severe hypomagnesaemia in long-term users of proton-pump inhibitors (PPIs).

PATIENTS

Two cases of severe hypomagnesaemia in adult long-term users of the PPI omeprazole, presenting with hypocalcaemic seizures.

MEASUREMENTS

We studied renal magnesium handling during an incremental intravenous magnesium infusion, and assessed total body magnesium status by the 24-h retention of the parenteral load. We also observed the effects of oral magnesium supplements whilst continuing the PPI, and the effect of withdrawal of the PPI.

RESULTS

Both patients were severely magnesium-depleted and had avid renal magnesium retention, implicating a failure of intestinal magnesium absorption. There was no evidence of generalized malabsorption. The hypomagnesaemia could be partially corrected by high dose oral magnesium supplementation, and resolved on withdrawal of PPIs.

CONCLUSIONS

PPI use can inhibit active magnesium transport in the intestine, though it is not clear if this is an idiosyncratic effect. Long-term PPI users who are highly adherent to treatment can eventually deplete total body magnesium stores and present with severe complications of hypomagnesaemia.

Growth factors in short-bowel syndrome patients

Malabsorption is a key finding in patients with short-bowel syndrome. Malabsorption of nonessential and essential nutrients, fluids, and electrolytes, if not compensated for by increased intake, leads to diminished body stores and subclinical and (eventually) clinical deficiencies. After intestinal resection, adaptation (a spontaneous progressive recovery from the malabsorptive disorder) may be evident. This article describes selected factors responsible for the morphologic and functional changes in the adaptive processes and presents results of clinical trials that use either growth hormone or glucagon-like peptide-2 to facilitate a condition of hyperadaptation in short-bowel patients.

Short bowel syndrome: current medical and surgical trends

Short bowel syndrome is a chronic malabsorptive state usually resulting from extensive small bowel resections. A combination of diarrhea, nutrient malabsorption, dysmotility, and bowel dilatation may constitute the clinical symptomatology of this syndrome. The remaining bowel undergoes a process called adaptation, which may replace lost intestinal function. Chronic complications include nutrient, electrolyte, and vitamin deficiencies. Therapy depends largely on the administration of various factors stimulating intestinal adaptation of the remaining bowel. If the patient despite medical therapy fails to return to oral diet alone, then long-term parenteral nutrition is required. However, long-term parenteral nutrition may gradually induce cholestatic liver disease. Surgical methods may be required for treatment including intestinal transplantation, as a last resort for the treatment of end-stage intestinal failure. The goal of this review is to analyze the clinical spectrum and pathophysiologic aspects of the syndrome, the process of intestinal adaptation, and to outline the medical and surgical methods currently used to treat this complicated group of patients.

Review article: intestinal failure

Intestinal failure is a specific disease entity resulting from intestinal resection or disease-associated malabsorption and characterized by the inability to maintain protein-energy, fluid, electrolyte or micronutrient balance. We performed a MEDLINE search (1966-2006) to identify relevant articles, using keywords intestinal failure, parenteral or enteral nutrition, intestinal fistula and short bowel syndrome. Causes of intestinal failure are varied, with self-limiting or 'Type 1' intestinal failure occurring relatively commonly following abdominal surgery, necessitating short-term fluid or nutritional support. The rarer, 'Type 2' intestinal failure, is associated with septic, metabolic and complex nutritional complications, usually following surgical resection in patients with Crohn's or mesenteric vascular disease. A multidisciplinary approach to the management of patients with Type 2 intestinal failure is crucial: resolution of sepsis is required before adequate nutritional repletion can be achieved, and it is important to optimize nutritional status, not only through enteral or parenteral supplementation, but also by addressing complications of short bowel syndrome, before considering definitive surgical reconstruction. A structured approach to the management of Type 2 intestinal failure should reduce the likelihood of these complex patients developing 'Type 3' intestinal failure, which is characterized by the need for long-term parenteral nutrition.

Glucagon-like peptide-2: update of the recent clinical trials

Although long-term parenteral nutrition is lifesaving in patients with intestinal failure, it is expensive and associated with serious complications such as catheter sepsis, venous occlusions, and liver failure and severely impairs the quality of life in the short bowel patients. Therefore, treatments that increase the absolute intestinal absorption, thereby eliminating or minimizing the need for parenteral support, are needed. In this respect, glucagon-like peptide 2 (GLP-2) has received attention. In this review, the nature of the short bowel syndrome is described, and the antisecretory, transit-modulating, but also intestinotrophic effects of GLP-2 are presented. As illustrated in 2 pilot studies, one using native GLP-2 and the other a degradation-resistant analogue, teduglutide, these new agents may prove important in optimizing remnant intestinal function, thereby eliminating the need for parenteral support and improving quality of life in short bowel patients with intestinal failure.

Ileostomy diarrhea

Ileostomy diarrhea is not an uncommon problem and can lead to considerable loss of quality of life. Unfortunately, well-designed therapeutic trials are lacking, and thus, treatment of patients with ileostomy diarrhea remains largely empiric. The majority of individuals will have "idiopathic" ileostomy diarrhea, or increased output due to proctocolectomy with limited ileal resection alone. Once other, less common causes are excluded, empiric treatment should be initiated with the safest, least costly option. In general, this consists of a dietary evaluation and symptomatic treatment with loperamide and advancing as needed to other, more expensive options, frequently with an increase in side effect profile. Other more recently evaluated treatment options include budesonide and oleic acid; however, efficacy has only been demonstrated in preliminary studies; further evaluation is needed. Limited data exist regarding success of surgical therapy such as reversed peristaltic ileal segments. It remains to be seen if surgery, other than ileostomy revision, has a role in the treatment of ileostomy diarrhea.

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.

Teduglutide (ALX-0600), a dipeptidyl peptidase IV resistant glucagon-like peptide 2 analogue, improves intestinal function in short bowel syndrome patients

BACKGROUND AND AIMS

Glucagon-like peptide 2 (GLP-2) may improve intestinal absorption in short bowel syndrome (SBS) patients with an end jejunostomy. Teduglutide (ALX-0600), a dipeptidyl peptidase IV resistant GLP-2 analogue, prolongs the intestinotrophic properties of GLP-2 in animal models. The safety and effect of teduglutide were investigated in SBS patients with and without a colon in continuity.

METHODS

Teduglutide was given subcutaneously for 21 days once or twice daily to 16 SBS patients in the per protocol investigational group, 10 with end jejunostomy (doses of 0.03 (n = 2), 0.10 (n = 5), or 0.15 (n = 3) mg/kg/day), one with <50% colon in continuity (dose 0.03 mg/kg/day), and five with > or = 50% colon in continuity (dose 0.10 mg/kg/day). Nutrient balance studies, D-xylose tests, and intestinal mucosa biopsies were performed at baseline, on the last three days of treatment, and after three weeks of follow up. Pre-study fasting native GLP-2 levels were determined for the five patients with > or = 50% colon in continuity.

RESULTS

Pooled across groups and compared with baseline, teduglutide increased absolute (+743 (477) g/day; p<0.001) and relative (+22 (16)%; p<0.001) wet weight absorption, urine weight (+555 (485) g/day; p<0.001), and urine sodium excretion (+53 (40) mmol/day; p<0.001). Teduglutide decreased faecal wet weight (-711 (734) g/day; p = 0.001) and faecal energy excretion (-808 (1453) kJ/day (-193 (347) kcal/day); p = 0.040). In SBS patients with end jejunostomy, teduglutide significantly increased villus height (+38 (45)%; p = 0.030), crypt depth (+22 (18)%; p = 0.010), and mitotic index (+115 (108)%; p = 0.010). Crypt depth and mitotic index did not change in colonic biopsies from SBS patients with colon in continuity. The most common side effects were enlargement of the stoma nipple and mild lower leg oedema. The improvements in intestinal absorption and decreases in faecal excretion noted after treatment had reversed after the drug free follow up period. A controlled study with a more robust design is ongoing in order to determine the optimal dosage of teduglutide for SBS patients to achieve the maximal effect and utility of this drug in clinical practice.

CONCLUSION

Teduglutide, at three dose levels for 21 days, was safe and well tolerated, intestinotrophic, and significantly increased intestinal wet weight absorption in SBS patients with an end jejunostomy or a colon in continuity.

Clinical significance of GLP-2 in short-bowel syndrome

Although long-term parenteral nutrition is lifesaving in patients with intestinal failure, it is expensive, severely impairs the quality of life in the short-bowel patients and is associated with serious complications such as catheter sepsis, venous occlusions and liver disease. Therefore, treatments that aim to minimize intestinal absorption, thereby eliminating or minimizing the need for parenteral support, are needed. As a result, glucagon-like peptide 2 (GLP-2) has received attention. In this review, the nature of short-bowel syndrome is described and the antisecretory, transit modulating and intestinotrophic effects of GLP-2 are presented. As illustrated in a pilot study, GLP-2 may prove to be important in the attempt to optimize remnant intestinal function thereby eliminating the need for parenteral support and improving quality of life in short-bowel patients with intestinal failure.

The medical management of intestinal failure: methods to reduce the severity

A new definition of intestinal failure is of reduced intestinal absorption so that macronutrient and/or water and electrolyte supplements are needed to maintain health or growth. Severe intestinal failure is when parenteral nutrition and/or fluid are needed and mild intestinal failure is when oral supplements or dietary modification suffice. Treatment aims to reduce the severity of intestinal failure. In the peri-operative period avoiding the administration of excessive amounts of intravenous saline (9 g NaCl/l) may prevent a prolonged ileus. Patients with intermittent bowel obstruction may be managed with a liquid or low-residue diet. Patients with a distal bowel enterocutaneous fistula may be managed with an enteral feed absorbed by the proximal small bowel while no oral intake may be needed for a proximal bowel enterocutaneous fistula. Patients undergoing high-dose chemotherapy can usually tolerate jejunal feeding. Rotating antibiotic courses may reduce small bowel bacterial overgrowth in patients with chronic intestinal pseudoobstruction. Restricting oral hypotonic fluids, sipping a glucose-saline solution (Na concentration of 90-120 mmol/l) and taking anti-diarrhoeal or anti-secretory drugs, reduces the high output from a jejunostomy. This treatment allows most patients with a jejunostomy and > 1 m functioning jejunum remaining to manage without parenteral support. Patients with a short bowel and a colon should consume a diet high in polysaccharides, as these compounds are fermented in the colon, and low in oxalate, as 25% of the oxalate will develop as calcium oxalate renal stones. Growth factors normally produced by the colon (e.g. glucagon-like peptide-2) to induce structural jejunal adaptation have been given in high doses to patients with a jejunostomy and do marginally increase the daily energy absorption.

Experimental approaches: dietary and hormone therapy

Patients who suffer from intestinal failure depend on parenteral support to maintain nutritional equilibrium. In this chapter, recommendations for evaluation the absorptive capacity of patients with intestinal failure are defined, and the evidence and magnitude of the effect of dietary and hormone therapy is given. Regarding dietary advice, the effects of employment of diets with various carbohydrate:fat ratios in short-bowel syndrome (SBS) patients with and without a preserved colon is presented. Focus has been placed on the use of growth hormone but also on the use of a novel intestinotrophic hormone, glucagon-like peptide 2, in the promotion of intestinal adaptation in SBS patients. Overall, the ultimate aim in the treatment of SBS patients is to optimize remnant intestinal function, thereby eliminating the need for parenteral support and improving quality of life in these patients.

Malnutrition and gastrointestinal disease

The recognition of several disease processes that cause or are associated with gastrointestinal malabsorption has led to extensive investigation into their pathogenesis, diagnosis, and treatment. This review of selected articles covers a range of subjects related to some of the more common malabsorptive disease. Selected topics including celiac disease, disaccharidase deficiencies, short bowel syndrome, and Crohn disease are discussed.

Enhancing bowel adaptation in short bowel syndrome

Malabsorption of both nonessential and essential nutrients, fluid, and electrolytes will, if not compensated for by increased intake, lead to diminished body stores and to subclinical and eventually clinical deficiencies. By definition, intestinal failure prevails when parenteral support is necessary to maintain nutritional equilibrium. After intestinal resection, adaptation, a progressive recovery from the malabsorptive disorder, may be seen. Research has focused on optimizing remnant intestinal function through dietary or pharmacologic interventions. In this review, factors responsible for the morphologic and functional changes in the adaptive processes are described. Results of clinical trials employing either growth hormone and glutamine or glucagon-like peptide-2 in short bowel patients are presented.

Malnutrition and gastrointestinal disease

The recognition of several disease processes that cause or are associated with gastrointestinal malabsorption has led to extensive investigation into their pathogenesis, diagnosis, and treatment. This review of selected articles covers a range of subjects related to some of the more common malabsorptive disease. Selected topics including celiac disease, disaccharidase deficiencies, short bowel syndrome, and Crohn disease are discussed.

Management of patients with a short bowel

There are two common types of adult patient with a short bowel, those with jejunum in continuity with a functioning colon and those with a jejunostomy. Both groups have potential problems of undernutrition, but this is a greater problem in those without a colon, as they do not derive energy from anaerobic bacterial fermentation of carbohydrate to short chain fatty acids in the colon. Patients with a jejunostomy have major problems of dehydration, sodium and magnesium depletion all due to a large volume of stomal output. Both types of patient have lost at least 60 cm of terminal ileum and so will become deficient of vitamin B₁₂. Both groups have a high prevalence of gallstones (45%) resulting from periods of biliary stasis. Patients with a retained colon have a 25% chance of developing calcium oxalate renal stones and they may have problems with D (-) lactic acidosis. The survival of patients with a short bowel, even if they need long-term parenteral nutrition, is good.

Small bowel review: normal physiology part 1

In the past year there have been many advances in the area of small bowel physiology and pathology and therapy. In preparation for this review, over 1500 papers were assessed. The focus is on presenting clinically useful information for the practising gastroenterologist. Selected important clinical learning points include the following: (1) glucose absorption mediated by SGLT1 is controlled by mRNA abundance, as well as by posttranscriptional processes including protein trafficking; (2) inducers of cytochrome P-450 decrease glucose and fructose absorption and increase glucose consumption in the intestine; (3) the regulated release of nutrients from the stomach into the upper intestine ensures that the modest intestinal transport reserve capacity is not exceeded; (4) hepatocyte growth factor and short-chain fatty acids may enhance intestinal adaptation and prevent the atrophy seen when total parenteral nutrition is infused; (5) inhibitors of pancreatic lipase and phospholipase H2 may be useful clinically to reduce absorption as part of a treatment program for obesity and hyperlipidemia; (6) several membrane-bound and cytosolic proteins have been identified in the enterocyte as well as in the hepatocyte and may be the target for the future therapeutic manipulation of bile acid metabolism and control of hyperlipidemia; (7) suspect bile acid malabsorption in the patient with otherwise unexplained chronic diarrhea; (8) a proportion of lipid absorption is protein-mediated, and this opens the way to targeting these proteins and thereby therapeutically modifying lipid absorption; (9) a high protein diet may be useful to increase the intestinal absorption of drugs transported by the H+/dipeptide cotransporter; (10) a metal transporter DCT1 has been identified, and this may open the way to a better understanding of disorders of, for example, iron and zinc metabolism; (11) the nutrient transporters such as SGLT1 are responsible for a portion of the intestinal absorption of water; (12) the influence of nitric oxide on intestinal water absorption and secretion depends on its concentration; (13) a trial of bile acid-sequestering agent may prove useful in the treatment of the patient who experiences diarrhea while taking an enteral diet; (14) a proteolytic extract from pineapple stems may prove to be useful to treat diarrhea, although the mechanism of this effect remains to be established; and (15) the antisecretory effect of the new peptide, sorbin, needs to be tested in a clinical situation on patients with diarrhea. Other new and promising antidiarrheal agents include bromelain, an extract from pineapple stems, and igmesine, a final sigma ligand.

Alteration in digestion and absorption of nutrients during profound acid suppression

Gastric acid suppression therapy has for many years been the cornerstone of the treatment of peptic disease. The availability of more potent inhibitors of gastric acid secretion and the increasing demand for maintenance therapy has renewed interest in the potential side-effects of profound and/or long-lasting therapy. This chapter focuses on the potential interference of gastric acid suppression therapy with the process of the digestion and absorption of nutrients. The theoretical mechanisms by which hypochlorhydria resulting from gastric acid suppression therapy may hamper digestion and absorption are multiple and well documented. Clinical studies evaluating the effect of gastric acid suppression therapy on the assimilation of nutrients are, on the other hand, scarce and have, moreover, yielded conflicting results. The reason for the latter may be related, at least in part, to elements of study design. Data indicating overt malabsorption or clear deficiencies in patients on long-term gastric acid suppression therapy are currently lacking. Nevertheless, it seems prudent, while awaiting the results of additional long-term studies, regularly to monitor these patients, especially those with increased nutrient demand, poor intake or suboptimal stores.

Pharmacotherapy and growth factors in the treatment of short bowel syndrome

A review of the pharmacologic substances and growth factors that have been studied experimentally and administered clinically for the management of short bowel syndrome is presented. The medical management of short bowel syndrome is multifaceted. In the acute phase, efforts focus on fluid and electrolyte management and the reduction of gastric acid output. As enteral feeding is initiated, antimotility and antisecretory agents may be effective in reducing gastrointestinal losses. Additional modalities of management, including nutrients and growth factors, may be directed at maximizing absorptive function beyond that which occurs with intestinal adaptation. Continued research aimed at further elucidating the process of intestinal adaptation may allow us to use the various peptides and hormones that act as growth factors for the bowel mucosa. Knowledge gained from these studies combined with gene therapy techniques will result in the permanent enhancement of intestinal function beyond the normal adaptation process, eliminate the dependence on total parenteral nutrition, and avoid the need for intestine transplantation.

Glucagon-like peptide 2 improves nutrient absorption and nutritional status in short-bowel patients with no colon

BACKGROUND & AIMS

Glucagon-like peptide 2 (GLP-2) is intestinotrophic, antisecretory, and transit-modulating in rodents, and it is mainly secreted from the intestinal mucosa of the terminal ileum and colon after food ingestion. We assessed the effect of GLP-2 on the gastrointestinal function in patients without a terminal ileum and colon who have functional short-bowel syndrome with severe malabsorption of wet weight (>1.5 kg/day) and energy (>2.3 MJ/day) and no postprandial secretion of GLP-2.

METHODS

Balance studies were performed before and after treatment with GLP-2, 400 microg subcutaneously twice a day for 35 days, in 8 patients (4-17 years from last bowel resection; 6 with Crohn's disease). Four patients received home parenteral nutrition (mean residual jejunum, 83 cm), and 4 did not (mean ileum resection, 106 cm). Biopsy specimens were taken from jejunal/ileal stomas, transit was measured by scintigraphy, and body composition was measured by dual-energy x-ray absorptiometry.

RESULTS

Treatment with GLP-2 improved the intestinal absorption of energy 3.5% +/- 4.0% (mean +/- SD) from 49.9% to 53.4% (P = 0.04), wet weight 11% +/- 12% from 25% to 36% (P = 0.04), and nitrogen 4.7% +/- 5.4% from 47.4% to 52.1% (P = 0.04). Body weight increased 1.2 +/- 1.0 kg (P = 0.01), lean body mass increased 2.9 +/- 1.9 kg (P = 0.004), fat mass decreased 1.8 +/- 1.3 kg (P = 0.007), and 24-hour urine creatinine excretion increased (P = 0.02). The time to 50% gastric emptying of solids increased 30 +/- 16 minutes from 89 to 119 minutes (P < 0.05). Small bowel transit time was not changed. Crypt depth and villus height were increased in 5 and 6 patients, respectively.

CONCLUSIONS

Treatment with GLP-2 improves intestinal absorption and nutritional status in short-bowel patients with impaired postprandial GLP-2 secretion in whom the terminal ileum and the colon have been resected.

Effect of high-dose growth hormone and glutamine on body composition, urine creatinine excretion, fatty acid absorption, and essential fatty acids status in short bowel patients: a randomized, double-blind, crossover, placebo-controlled study

BACKGROUND

Positive effects of high dose growth hormone and glutamine (GH + GLN) on body composition in short bowel patients have been described. Lack of effects on intestinal absorption found in some studies has been ascribed to concomitant essential fatty acid (EFA) deficiency. This study describes changes in body weight (BW) and composition, 24-h urine creatinine excretion, intestinal fatty acid absorption (total, saturated, unsaturated and EFA), and EFA status in relation to treatment with GH + GLN in 8 short bowel patients.

METHODS

A double-blind, crossover study between placebo and growth hormone (mean, 0.12 mg/kg/day) plus oral (mean, 28 g/day) and parenteral glutamine (mean, 5.2 g/day) for 28 days. Body composition was measured by dual-energy absorptiometry (DEXA) scans. Intestinal fatty acid absorption was evaluated in balance studies, and EFAs were measured in plasma phospholipids by gas liquid chromatography.

RESULTS

Active treatment did not increase BW, lean body mass (LBM), fat mass (FM) and bone mass significantly compared with placebo treatment, but BW increased 1.03 kg (1.7%, P < 0.05), LBM 2.93 kg (8.7%, P < 0.001) and FM decreased 2.41 kg (10.6%, P < 0.001) in comparison with baseline. Twenty-four-hour urine creatinine excretion did not differ between study periods. No changes in intestinal absorption of fatty acids were seen, and no changes in EFAs measured in plasma phospholipids were observed. Only 1 of 8 patients, who did not receive parenteral lipids, had a Holman index above 0.2, indicative of EFA deficiency. All developed peripheral oedema.

CONCLUSIONS

Combined high dose growth hormone and glutamine administered for 4 weeks, did not improve absorption of fatty acids or EFA status in short bowel patients. No changes in BW or composition were seen when comparing treatment to placebo periods. The increase in LBM measured by DEXA scan, comparing treatment and baseline periods, was not accompanied by an increase in the 24-h urinary creatinine excretion and is suspected to be associated with an accumulation in extracellular fluids.