Preoperative enteral nutrition in adults with complicated Crohn's disease: Effect on disease outcomes and gut microbiota

ECCO Guidelines on Therapeutics in Crohn's Disease: Surgical Treatment

This article is the second in a series of two publications on the European Crohn's and Colitis Organisation [ECCO] evidence-based consensus on the management of Crohn's disease. The first article covers medical management; the present article addresses surgical management, including preoperative aspects and drug management before surgery. It also provides technical advice for a variety of common clinical situations. Both articles together represent the evidence-based recommendations of the ECCO for Crohn's disease and an update of prior ECCO guidelines.

Multimodal Prehabilitation for Patients with Crohn's Disease Scheduled for Major Surgery: A Narrative Review

Approximately 15-50% of patients with Crohn's disease (CD) will require surgery within ten years following the diagnosis. The management of modifiable risk factors before surgery is essential to reduce postoperative complications and to promote a better postoperative recovery. Preoperative malnutrition reduced functional capacity, sarcopenia, immunosuppressive medications, anemia, and psychological distress are frequently present in CD patients. Multimodal prehabilitation consists of nutritional, functional, medical, and psychological interventions implemented before surgery, aiming at optimizing preoperative status and improve postoperative recovery. Currently, studies evaluating the effect of multimodal prehabilitation on postoperative outcomes specifically in CD are lacking. Some studies have investigated the effect of a single prehabilitation intervention, of which nutritional optimization is the most investigated. The aim of this narrative review is to present the physiologic rationale supporting multimodal surgical prehabilitation in CD patients waiting for surgery, and to describe its main components to facilitate their adoption in the preoperative standard of care.

Practical application of the Crohn's disease exclusion diet as therapy in an adult Australian population

There is demand from patients and clinicians to use the Crohn's disease exclusion diet (CDED) with or without partial enteral nutrition (PEN). However, the therapeutic efficacy and nutritional adequacy of this therapy are rudimentary in an adult population. This review examines the evidence for the CDED in adults with active luminal Crohn's disease and aims to provide practical guidance on the use of the CDED in Australian adults. A working group of nine inflammatory bowel disease (IBD) dietitians of DECCAN (Dietitians Crohn's and Colitis Australian Network) and an IBD gastroenterologist was established. A literature review was undertaken to examine (1) clinical indications, (2) monitoring, (3) dietary adequacy, (4) guidance for remission phase, and (5) diet reintroduction after therapy. Each diet phase was compared with Australian reference ranges for food groups and micronutrients. CDED with PEN is nutritionally adequate for adults containing sufficient energy and protein and meeting > 80% of the recommended daily intake of key micronutrients. An optimal care pathway for the clinical use of the CDED in an adult population was developed with accompanying consensus statements, clinician toolkit, and patient education brochure. Recommendations for weaning from the CDED to the Australian dietary guidelines were developed. The CDED + PEN provides an alternate partial food-based therapy for remission induction of active luminal Crohn's disease in an adult population. The CDED + PEN should be prioritized over CDED alone and prescribed by a specialist IBD dietitian. DECCAN cautions against using the maintenance diet beyond 12 weeks until further evidence becomes available.

Preoperative Exclusive Enteral Nutrition Is Associated With Reduced Skin and Soft Tissue and Intra-abdominal Infections in Patients With Crohn's Disease Undergoing Intestinal Surgery: Results from a Meta-Analysis

BACKGROUND

Malnutrition is an independent risk factor for adverse postoperative outcomes and is common among patients with Crohn's disease (CD). The objective of this meta-analysis was to precisely quantify the association of preoperative exclusive enteral nutrition (EEN) and total parenteral nutrition (TPN) with surgical outcomes in patients undergoing intestinal surgery for CD.

METHODS

PubMed, Embase, and Scopus were queried for comparative studies evaluating the impact of preoperative nutritional support on postoperative outcomes in patients undergoing surgery for CD. Random effects modeling was used to compute pooled estimates of risk difference. Heterogeneity was assessed using I2.

RESULTS

Fourteen studies, all nonrandomized cohort studies, met inclusion criteria for studying EEN. After pooling data from 14 studies (874 EEN treated and 1044 control patients), the relative risk of intra-abdominal septic complications was decreased 2.1-fold in patients receiving preoperative EEN (relative risk 0.47, 95% confidence interval [CI], 0.35-0.63, I2 = 0.0%). After pooling data from 9 studies (638 EEN treated and 819 control patients), the risk of skin and soft tissue infection was decreased 1.6-fold (relative risk 0.63; 95% CI, 0.42-0.94, I2 = 42.7%). No significant differences were identified in duration of surgery, length of bowel resected, or operative blood loss. Among the 9 studies investigating TPN, no significant differences were identified in infectious outcomes.

CONCLUSIONS

Preoperative nutritional optimization with EEN was associated with reduced risk of infectious complications in CD patients undergoing intestinal surgery. Preoperative nutritional support with EEN should be considered for optimizing outcomes in CD patients requiring bowel resection surgery.

Therapeutic Advances in Gut Microbiome Modulation in Patients with Inflammatory Bowel Disease from Pediatrics to Adulthood

There is mounting evidence that the gut microbiota plays an important role in the pathogenesis of inflammatory bowel disease (IBD). For the past decade, high throughput sequencing-based gut microbiome research has identified characteristic shifts in the composition of the intestinal microbiota in patients with IBD, suggesting that IBD results from alterations in the interactions between intestinal microbes and the host’s mucosal immune system. These studies have been the impetus for the development of new therapeutic approaches targeting the gut microbiome, such as nutritional therapies, probiotics, fecal microbiota transplant and beneficial metabolic derivatives. Innovative technologies can further our understanding of the role the microbiome plays as well as help to evaluate how the different approaches in microbiome modulation impact clinical responses in adult and pediatric patients. In this review, we highlight important microbiome studies in patients with IBD and their response to different microbiome modulation therapies, and describe the differences in therapeutic response between pediatric and adult patient cohorts.

Review of exclusive enteral therapy in adult Crohn's disease

Background

Exclusive enteral nutrition (EEN) is a potentially effective but underused therapy for Crohn’s disease (CD) in adults. It is first-line induction treatment for paediatric patients but remains a second-line or third-line therapy in adults.

Objective

To analyse the evidence for EEN in adult patients with CD, and summarise this in a narrative review.

Methods

In April/May 2020 and July 2021, a literature search was performed using the Medical Subject Headings (MeSH) terms: ‘Crohn’s disease’, ‘CD’, ‘inflammatory bowel disease’, ‘IBD’, ‘exclusive enteral nutrition’, ‘enteral nutrition’, ‘EEN’, in PubMed, Scopus, Cochrane. Additional studies were obtained from references of search result articles as well as general reading. Studies with adult patients with CD treated with EEN were selected. 79 articles of relevance were found. Where data in adults were lacking, data from paediatric studies as extrapolated with care.

Results

EEN in adult patients been shown to improve clinical, biomarker, endoscopic and radiologic measures of disease activity. EEN avoids the potential adverse effects of recurrent corticosteroids for induction such as metabolic derangements and opportunistic infections. EEN has also demonstrated benefits among adult patients with fistulising and stricturing CD. It may avoid surgery in such patients. Preoperative EEN has also been shown to reduce postoperative complications and recurrence. There appears to be benefits in combing EEN with antitumour necrosis factor agents, however, benefits of combination therapy with other biologics are less clear. A major drawback of EEN therapy in adults has been poor compliance. More palatable polymeric formulations improved patient education and dietitian support may overcome this. Evidence in adults is limited to small studies, often with suboptimal control arms and lack of blinding. Larger scale studies with improved study design are needed to confirm these beneficial effects.

Conclusion

Despite limitations in evidence EEN should be considered in treating adults with CD.

Optimizing Inpatient Nutrition Care of Adult Patients with Inflammatory Bowel Disease in the 21st Century

Malnutrition is highly prevalent in inflammatory bowel disease (IBD) patients and disproportionately affects those admitted to hospital. Malnutrition is a risk factor for many complications in IBD, including prolonged hospitalization, infection, greater need for surgery, development of venous thromboembolism, post-operative complications, and mortality. Early screening for malnutrition and prompt nutrition intervention if indicated has been shown to prevent or mitigate many of these outlined risk factors. There are many causes of malnutrition in IBD including reduced oral food intake, medications, active inflammation, and prior surgical resections. Hospitalization can further compound pre-existing malnutrition through inappropriate diet restrictions, nil per os (NPO) for endoscopy and imaging, or partial bowel obstruction, resulting in "post-hospital syndrome" after discharge and readmission. The aim of this article is to inform clinicians of the prevalence and consequences of malnutrition in IBD, as well as available screening and assessment tools for diagnosis, and to offer an organized approach to the nutritional care of hospitalized adult IBD patients.