ESPEN guideline on Clinical Nutrition in inflammatory bowel disease.

The present guideline is an update and extension of the ESPEN scientific guideline on Clinical Nutrition in Inflammatory Bowel Disease published first in 2017. The guideline has been rearranged according to the ESPEN practical guideline on Clinical Nutrition in Inflammatory Bowel Disease published in 2020. All recommendations have been checked and, if needed, revised based on new literature, before they underwent the ESPEN consensus procedure. Moreover, a new chapter on microbiota modulation as a new option in IBD treatment has been added. The number of recommendations has been increased to 71 recommendations in the guideline update. The guideline is aimed at professionals working in clinical practice, either in hospitals or in outpatient medicine, and treating patients with IBD. General aspects of care in patients with IBD, and specific aspects during active disease and in remission are addressed. All recommendations are equipped with evidence grades, consensus rates, short commentaries and links to cited literature.

Exercise and Nutritional Interventions in Patients with Advanced Gastroesophageal Cancer: A Systematic Review.

PURPOSE: The quality of life and survival of patients with advanced gastroesophageal cancer can be improved. Positive effects of exercise and nutritional interventions on quality of life and potential effects on cancer outcomes are found in gastroesophageal cancer in the curative setting, as well as in other cancer types. We therefore systematically reviewed the current literature on the effect of exercise and nutritional interventions on various outcomes in patients with advanced gastroesophageal cancer. METHODS: We searched on the 11th of June 2021 in Pubmed, Embase and the Cochrane library for publications of randomized trials and observational studies on exercise and nutritional interventions (either combined or as separate intervention) in patients with advanced gastroesophageal cancer. The outcomes of interest were overall survival, progression free survival, quality of life, chemotherapy toxicity, and chemotherapy adherence. RESULTS: We screened 1,764 records for eligibility and included one study in our analysis. The other 1,763 were excluded for various reasons, most frequently an incorrect study population (e.g. both curable and incurable patients) or an incorrect intervention. One retrospective cohort study of 40 patients with advanced gastric cancer who received first line chemotherapy was included. It was stated that 'no significant differences in terms of overall and progression free survival were reported between the two groups of patients.' No absolute numbers were provided. CONCLUSION: Our systematic review did not identify any high quality studies on exercise and nutritional interventions in advanced gastroesophageal cancer. We deem a randomized clinical trial on this topic to be highly needed.

Nutritional problems of patients with COVID-19 receiving dietetic treatment in primary care.

BACKGROUND: The nutritional problems of patients who are hospitalised for COVID-19 are becoming increasingly clear. However, a large group of patients have never been hospitalised and also appear to experience persistent nutritional problems. The present study describes the nutritional status, risk of sarcopaenia and nutrition-related complaints of patients recovering from COVID-19 receiving dietetic treatment in primary care. METHODS: In this retrospective observational study, data were collected during dietetic treatment by a primary care dietitian between April and December 2020. Both patients who had and had not been admitted to the hospital were included at their first visit to a primary care dietitian. Data on nutritional status, risk of sarcopaenia and nutrition-related complaints were collected longitudinally. RESULTS: Data from 246 patients with COVID-19 were collected. Mean ± SD age was 57 ± 16 years and 61% of the patient population was female. At first consultation, two thirds of patients were classified as overweight or obese (body mass index >25 kg m-2 ). The majority had experienced unintentional weight loss because of COVID-19. Additionally, 55% of hospitalised and 34% of non-hospitalised patients had a high risk of sarcopaenia. Most commonly reported nutrition-related complaints were decreased appetite, shortness of breath, changed or loss of taste and feeling of being full. Nutrition-related complaints decreased after the first consultation, but remained present over time. CONCLUSIONS: In conclusion, weight changes, risk of sarcopaenia and nutrition-related complaints were prevalent in patients with COVID-19, treated by a primary care dietitian. Nutrition-related complaints improved over time, but remained prevalent until several months after infection.

[ESPEN guideline: Clinical nutrition in inflammatory bowel disease]. / Guía ESPEN: Nutrición clínica en la enfermedad inflamatoria intestinal.

Introduction: Introduction: the ESPEN guideline offers a multidisciplinary focus on clinical nutrition in inflammatory bowel disease (IBD). Methodology: the guideline is based on a extensive systematic review of the literature, but relies on expert opinion when objective data are lacking or inconclusive. The conclusions and 64 recommendations have been subject to full peer review and a Delphi process, in which uniformly positive responses (agree or strongly agree) were required. Results: IBD is increasingly common and potential dietary factors in its etiology are briefly reviewed. Malnutrition is highly prevalent in IBD - especially in Crohn's disease. Increased energy and protein requirements are observed in some patients. The management of malnutrition in IBD is considered within the general context of support for malnourished patients. Treatment of iron deficiency (parenterally, if necessary) is strongly recommended. Routine provision of a special diet in IBD is not, however, supported. Parenteral nutrition is indicated only when enteral nutrition has failed or is impossible. The recommended perioperative management of patients with IBD undergoing surgery accords with general ESPEN guidance for patients having abdominal surgery. Probiotics may be helpful in UC but not in Crohn's disease. Primary therapy using nutrition to treat IBD is not supported in ulcerative colitis but is moderately well supported in Crohn's disease, especially in children, where the adverse consequences of steroid therapy are proportionally greater. However, exclusion diets are generally not recommended and there is little evidence to support any particular formula feed when nutritional regimens are constructed. Conclusions: available objective data to guide nutritional support and primary nutritional therapy in IBD are presented as 64 recommendations, of which 9 are very strong recommendations (grade A), 22 are strong recommendations (grade B), and 12 are based only on sparse evidence (grade 0); 21 recommendations are good practice points (GPP).

Introducción: Introducción: la guía ESPEN ofrece un enfoque multidisciplinar de la nutrición clínica en la enfermedad inflamatoria intestinal (EII). Metodología: la guía se basa en una extensa revisión sistemática de la literatura y en la opinión de expertos cuando faltan datos objetivos o estos no son concluyentes. Las conclusiones y las 64 recomendaciones han sido objeto de una revisión completa por pares y de un proceso Delphi en el que se requerían respuestas fuertemente positivas (de acuerdo o totalmente de acuerdo). Resultados: la EII es cada vez más común y se revisan brevemente los posibles factores dietéticos en su etiología. La desnutrición es muy prevalente en la EII, especialmente en la enfermedad de Crohn. En algunos pacientes se observan mayores requerimientos de energía y proteínas. El manejo de la desnutrición en la EII se considera dentro del contexto general de apoyo a los pacientes desnutridos. Se recomienda fuertemente el tratamiento de la deficiencia de hierro (por vía parenteral, si es necesario). Sin embargo, no se aconseja la prescripción de rutina de una dieta especial en la EII. La nutrición parenteral está indicada solo cuando la nutrición enteral ha fallado o es imposible. El manejo perioperatorio recomendado de los pacientes con EII sometidos a cirugía se hace de acuerdo con la guía general de la ESPEN para pacientes sometidos a cirugía abdominal. Los probióticos pueden ser útiles en la CU pero no en la enfermedad de Crohn. El tratamiento primario con nutrición para tratar la EII no está respaldado en la colitis ulcerosa, aunque está moderadamente bien soportado en la enfermedad de Crohn, especialmente en los niños, donde las consecuencias adversas de la terapia con esteroides son proporcionalmente mayores. Sin embargo, las dietas de exclusión generalmente no se recomiendan y hay poca evidencia que respalde cualquier fórmula de nutrición en particular cuando se realizan regímenes nutricionales. Conclusiones: los datos objetivos disponibles para guiar el apoyo nutricional y la terapia nutricional primaria en la EII se presentan como 64 recomendaciones, de las cuales 9 son recomendaciones muy fuertes (grado A), 22 son recomendaciones fuertes (grado B) y 12 se basan solo en evidencia escasa (grado 0); 21 recomendaciones son recomendaciones de buenas prácticas (GPP).

State of the art: the role of citrulline as biomarker in patients with chemotherapy- or graft-versus-host-disease-induced mucositis.

PURPOSE OF REVIEW: Serum or plasma citrulline levels are used as biomarker for a broad spectrum of intestinal functions. During high-dose chemotherapy, citrulline levels are decreased due to mucositis, a common side effect of chemotherapy. This may decrease intestinal function and result in diarrhea. In this review, most recent studies investigating citrulline as biomarker for intestinal function are discussed, with focus on patients with oncological diseases, specifically hematological malignancies with chemotherapy- or Graft-versus-Host-disease (GVHD)-induced mucositis. RECENT FINDINGS: Citrulline has recently been widely studied in relation to intestinal function and various clinical conditions. It seems therefore a promising noninvasive biomarker in clinical practice for more than intestinal function alone. The association between citrulline levels and intestinal function in patients with hematological malignancies, with or without mucositis remains unclear, as no other parameters of intestinal function for this purpose were assessed. SUMMARY: In conclusion, citrulline seems to be a promising noninvasive biomarker for various intestinal conditions in general, and potentially for intestinal function in patients with chemotherapy- or GVHD-induced mucositis. It is unclear from recent literature whether high fecal volume or diarrhea as side effect, results in impaired intestinal function and severe malabsorption and if citrulline biomarkers can be useful to detect this.

Poor nutritional status, risk of sarcopenia and nutrition related complaints are prevalent in COVID-19 patients during and after hospital admission.

BACKGROUND AND AIMS: Patients with COVID-19 infection presents with a broad clinical spectrum of symptoms and complications. As a consequence nutritional requirements are not met, resulting in weight- and muscle loss, and malnutrition. The aim of the present study is to delineate nutritional complaints, the (course of the) nutritional status and risk of sarcopenia of COVID-19 patients, during hospitalisation and after discharge. METHODS: In this prospective observational study in 407 hospital admitted COVID-19 patients in four university and peripheral hospitals, data were collected during dietetic consultations. Presence of nutrition related complaints (decreased appetite, loss of smell, changed taste, loss of taste, chewing and swallowing problems, nausea, vomiting, feeling of being full, stool frequency and consistency, gastric retention, need for help with food intake due to weakness and shortness of breath and nutritional status (weight loss, BMI, risk of sarcopenia with SARC-F ≥4 points) before, during hospital stay and after discharge were, where possible, collected. RESULTS: Included patients were most men (69%), median age of 64.8 ± 12.4 years, 60% were admitted to ICU at any time point during hospitalisation with a median LOS of 15 days and an in-hospital mortality rate of 21%. The most commonly reported complaints were: decreased appetite (58%), feeling of being full (49%) and shortness of breath (43%). One in three patients experienced changed taste, loss of taste and/or loss of smell. Prior to hospital admission, 67% of the patients was overweight (BMI >25 kg/m2), 35% of the patients was characterised as malnourished, mainly caused by considerable weight loss. Serious acute weight loss (>5 kg) was showed in 22% of the patents during the hospital stay; most of these patients (85%) were admitted to the ICU at any point in time. A high risk of sarcopenia (SARC-F ≥ 4 points) was scored in 73% of the patients during hospital admission. CONCLUSION: In conclusion, one in five hospital admitted COVID-19 patients suffered from serious acute weight loss and 73% had a high risk of sarcopenia. Moreover, almost all patients had one or more nutritional complaints. Of these complaints, decreased appetite, feeling of being full, shortness of breath and changed taste and loss of taste were the most predominant nutrition related complaints. These symptoms have serious repercussions on nutritional status. Although nutritional complaints persisted a long time after discharge, only a small group of patients received dietetic treatment after hospital discharge in recovery phase. Clinicians should consider the risks of acute malnutrition and sarcopenia in COVID-19 patients and investigate multidisciplinary treatment including dietetics during hospital stay and after discharge.

ESPEN practical guideline: Clinical Nutrition in inflammatory bowel disease.

The present guideline is the first of a new series of "practical guidelines" based on more detailed scientific guidelines produced by ESPEN during the last few years. The guidelines have been shortened and now include flow charts that connect the individual recommendations to logical care pathways and allow rapid navigation through the guideline. The purpose of the present practical guideline is to provide an easy-to-use tool to guide nutritional support and primary nutritional therapy in inflammatory bowel disease (IBD). The guideline is aimed at professionals working in clinical practice, either in hospitals or in outpatient medicine, and treating patients with IBD. In 40 recommendations, general aspects of care in patients with IBD, and specific aspects during active disease and in remission are addressed. All recommendations are equipped with evidence grades, consensus rates, short commentaries and links to cited literature.

Perioperative Dietary Therapy in Inflammatory Bowel Disease.

BACKGROUND AND AIMS: The incidence of inflammatory bowel disease [IBD] is rising worldwide and no cure is available. Many patients require surgery and they often present with nutritional deficiencies. Although randomised controlled trials of dietary therapy are lacking, expert IBD centres have long-established interdisciplinary care, including tailored nutritional therapy, to optimise clinical outcomes and resource utilisation. This topical review aims to share expertise and offers current practice recommendations to optimise outcomes of IBD patients who undergo surgery. METHODS: A consensus expert panel consisting of dietitians, surgeons, and gastroenterologists, convened by the European Crohn's and Colitis Organisation, performed a systematic literature review. Nutritional evaluation and dietary needs, perioperative optimis ation, surgical complications, long-term needs, and special situations were critically appraised. Statements were developed using a Delphi methodology incorporating three successive rounds. Current practice positions were set when ≥80% of participants agreed on a recommendation. RESULTS: A total of 26 current practice positions were formulated which address the needs of IBD patients perioperatively and in the long term following surgery. Routine screening, perioperative optimisation by oral, enteral, or parenteral nutrition, dietary fibre, and supplements were reviewed. IBD-specific situations, including management of patients with a restorative proctocolectomy, an ostomy, strictures, or short-bowel syndrome, were addressed. CONCLUSIONS: Perioperative dietary therapy improves the outcomes of IBD patients who undergo a surgical procedure. This topical review shares interdisciplinary expertise and provides guidance to optimise the outcomes of patients with Crohn's disease and ulcerative colitis. taking advantage of contemporary nutrition science.

Skeletal muscle analyses: agreement between non-contrast and contrast CT scan measurements of skeletal muscle area and mean muscle attenuation.

Low skeletal muscle area (SMA) and muscle radiation attenuation (MRA) have been associated with poor prognosis in various patient populations. Both non-contrast and contrast CT scans are used to determine SMA and MRA. The effect of the use of a contrast agent on SMA and MRA is unknown. Therefore, we investigated agreement between these two scan options. SMA and MRA of 41 healthy individuals were analysed on a paired non-contrast and contrast single CT scan, and agreement between paired scan results was assessed with use of Bland-Altman plots, intraclass correlation coefficients (ICCs), standard error of measurements (SEM) and smallest detectable differences at a 95% confidence level (SDD95 ). Analyses were stratified by tube voltage. Difference in SMA between non-contrast and contrast scans made with a different tube voltage was 7·0 ± 7·5 cm2 ; for scans made with the same tube voltage this was 2·3 ± 1·7 cm2 . Agreement was excellent for both methods: ICC: 0·952, SEM: 7·2 cm2 , SDD95 : 19·9 cm2 and ICC: 0·997, SEM: 2·0 cm2 , SDD95 : 5·6 cm2 , respectively. MRA of scans made with a different tube voltage differed 1·3 ± 11·3 HU, and agreement was poor (ICC: 0·207, SEM: 7·9 HU, SDD95 : 21·8 HU). For scans made with the same tube voltage the difference was 6·7 ± 3·2 HU, and agreement was good (ICC: 0·682, SEM: 5·3 HU, SDD95 : 14·6 HU). In conclusion, SMA and MRA can be slightly influenced by the use of contrast agent. To minimise measurement error, image acquisition parameters of the scans should be similar.

Research Gaps in Diet and Nutrition in Inflammatory Bowel Disease. A Topical Review by D-ECCO Working Group [Dietitians of ECCO].

Although the current doctrine of IBD pathogenesis proposes an interaction between environmental factors and gut microbiota in genetically susceptible individuals, dietary exposures have attracted recent interest and are, at least in part, likely to explain the rapid rise in disease incidence and prevalence. The D-ECCO working group along with other ECCO experts with expertise in nutrition, microbiology, physiology, and medicine reviewed the evidence investigating the role of diet and nutritional therapy in the onset, perpetuation, and management of IBD. A narrative topical review is presented where evidence pertinent to the topic is summarised collectively under three main thematic domains: i] the role of diet as an environmental factor in IBD aetiology; ii] the role of diet as induction and maintenance therapy in IBD; and iii] assessment of nutritional status and supportive nutritional therapy in IBD. A summary of research gaps for each of these thematic domains is proposed, which is anticipated to be agenda-setting for future research in the area of diet and nutrition in IBD.

Intravenous citrulline generation test to assess intestinal function in intensive care unit patients.

BACKGROUND: Assessment of a quantifiable small intestinal function test is cumbersome. Fasting citrulline concentrations have been proposed as a measure of enterocyte function and elaborated into a citrulline generation test (CGT), which is applicable only when glutamine is administered orally. CGT is an oral test, limiting its use, for example, in critically ill patients. OBJECTIVE: Assessment of normative values and feasibility of an intravenously performed CGT in intensive care unit (ICU) patients with presumed gastrointestinal motility disturbances, especially when performed intravenously. DESIGN: CGT reference values were determined in 16 stable ICU patients using two different CGT methods, namely following either enteral or intravenous glutamine administration and both with simultaneous arterial and venous plasma citrulline sampling at six time-points. Plasma amino acid analysis was performed using reverse-phase high-performance liquid chromatography. RESULTS: The median total generation of citrulline in 90 min (CGT iAUCT90) was markedly higher with arterial citrulline sampling compared with venous citrulline sampling, being 724±585 and 556±418 µmol/L/min for enteral glutamine, respectively (p=0.02) and 977±283 and 769±231 µmol/L/min for intravenous glutamine, respectively (p=0.0004). The median slope (time-dependent increase) for plasma arterial and venous citrulline during the CGT was 0.20±0.16 and 0.18±0.12 µmol/L/min for enteral glutamine, respectively (p=0.004) and 0.22±0.16 and 0.19±0.05 µmol/L/min for intravenous glutamine, respectively (p=0.02). CONCLUSION: Intravenous glutamine administration combined with arterial plasma citrulline sampling yielded the least variation in CGT characteristics in stable ICU patients. A 2-point measurement test had comparable test characteristics as a 6-point measurement CGT and seems promising.

ESPEN guideline: Clinical nutrition in inflammatory bowel disease.

INTRODUCTION: The ESPEN guideline presents a multidisciplinary focus on clinical nutrition in inflammatory bowel disease (IBD). METHODOLOGY: The guideline is based on extensive systematic review of the literature, but relies on expert opinion when objective data were lacking or inconclusive. The conclusions and 64 recommendations have been subject to full peer review and a Delphi process in which uniformly positive responses (agree or strongly agree) were required. RESULTS: IBD is increasingly common and potential dietary factors in its aetiology are briefly reviewed. Malnutrition is highly prevalent in IBD - especially in Crohn's disease. Increased energy and protein requirements are observed in some patients. The management of malnutrition in IBD is considered within the general context of support for malnourished patients. Treatment of iron deficiency (parenterally if necessary) is strongly recommended. Routine provision of a special diet in IBD is not however supported. Parenteral nutrition is indicated only when enteral nutrition has failed or is impossible. The recommended perioperative management of patients with IBD undergoing surgery accords with general ESPEN guidance for patients having abdominal surgery. Probiotics may be helpful in UC but not Crohn's disease. Primary therapy using nutrition to treat IBD is not supported in ulcerative colitis, but is moderately well supported in Crohn's disease, especially in children where the adverse consequences of steroid therapy are proportionally greater. However, exclusion diets are generally not recommended and there is little evidence to support any particular formula feed when nutritional regimens are constructed. CONCLUSIONS: Available objective data to guide nutritional support and primary nutritional therapy in IBD are presented as 64 recommendations, of which 9 are very strong recommendations (grade A), 22 are strong recommendations (grade B) and 12 are based only on sparse evidence (grade 0); 21 recommendations are good practice points (GPP).

Clinical nutrition in the hepatogastroenterology curriculum.

Gastroenterology (GE) used to be considered a subspecialty of internal medicine. Today, GE is generally recognized as a wide-ranging specialty incorporating capacities, such as hepatology, oncology and interventional endoscopy, necessitating GE-expert differentiation. Although the European Board of Gastroenterology and Hepatology has defined specific expertise areas in Advanced endoscopy, hepatology, digestive oncology and clinical nutrition, training for the latter topic is lacking in the current hepatogastroenterology (HGE) curriculum. Given its relevance for HGE practice, and being at the core of gastrointestinal functioning, there is an obvious need for training in nutrition and related issues including the treatment of disease-related malnutrition and obesity and its associated metabolic derangements. This document aims to be a starting point for the integration of nutritional expertise in the HGE curriculum, allowing a central role in the management of malnutrition and obesity. We suggest minimum endpoints for nutritional knowledge and expertise in the standard curriculum and recommend a focus period of training in nutrition issues in order to produce well-trained HGE specialists. This article provides a road map for the organization of such a training program. We would highly welcome the World Gastroenterology Organisation, the European Board of Gastroenterology and Hepatology, the American Gastroenterology Association and other (inter)national Gastroenterology societies support the necessary certifications for this item in the HGE-curriculum.

Refractory celiac disease and EATL patients show severe malnutrition and malabsorption at diagnosis.

BACKGROUND & AIMS: Refractory celiac disease type II (RCDII) and EATL (Enteropathy Associated T-cell Lymphoma) are (pre)malignant complications of celiac disease (CD). Data on malnutrition and intestinal absorption is lacking in these patients. Therefore, the aim of the study is to comprehensively assess nutritional status and intestinal absorption capacity of patients with RCDII and EATL, compared with data of newly diagnosed CD patients. METHODS: Observational study in tertiary care setting in RCDII (n = 24, 63.8 ± 8.2 y), EATL (n = 25, 62.3 ± 5.7 y) and CD patients (n = 43, 45.6 ± 14.8 y). At diagnosis, anthropometry (BMI, unintentional weight loss, fat-free mass index (FFMI), handgrip strength (HGS), nutritional intake, fecal losses and Resting Energy Expenditure (REE)) were assessed. RESULTS: Low BMI (<18.5) was more often observed in RCDII patients than in CD or EATL patients (in 33%, 12% and 12%, respectively, p = 0.029). EATL patients more frequently had unintentional weight loss (>10%) than CD or RCDII patients (in 58%, 19% and 39% of patients, respectively; p = 0.005/0.082). Energy malabsorption (<85%) was detected in 44% and 33% of RCDII and EATL patients, vs 21.6% in CD (NS). Fecal energy losses were higher in RCDII than in CD patients (589 ± 451 vs 277 ± 137 kcal/d, p = 0.017). REE was underestimated by predicted-REE with>10% in 60% of RCDII, 89% of EATL, and 38% of CD patients (p = 0.006). Low FFMI and HGS were detected in one third and two thirds of all patients, respectively. CONCLUSIONS: The nutritional status of patients with RCDII and EATL is inferior compared with untreated naïve CD patients at presentation. Both malabsorption as well as hypermetabolism contribute to malnutrition.

Vitamin and mineral deficiencies are highly prevalent in newly diagnosed celiac disease patients.

Malabsorption, weight loss and vitamin/mineral-deficiencies characterize classical celiac disease (CD). This study aimed to assess the nutritional and vitamin/mineral status of current "early diagnosed" untreated adult CD-patients in the Netherlands. Newly diagnosed adult CD-patients were included (n = 80, 42.8 ± 15.1 years) and a comparable sample of 24 healthy Dutch subjects was added to compare vitamin concentrations. Nutritional status and serum concentrations of folic acid, vitamin A, B6, B12, and (25-hydroxy) D, zinc, haemoglobin (Hb) and ferritin were determined (before prescribing gluten free diet). Almost all CD-patients (87%) had at least one value below the lower limit of reference. Specifically, for vitamin A, 7.5% of patients showed deficient levels, for vitamin B6 14.5%, folic acid 20%, and vitamin B12 19%. Likewise, zinc deficiency was observed in 67% of the CD-patients, 46% had decreased iron storage, and 32% had anaemia. Overall, 17% were malnourished (>10% undesired weight loss), 22% of the women were underweight (Body Mass Index (BMI) < 18.5), and 29% of the patients were overweight (BMI > 25). Vitamin deficiencies were barely seen in healthy controls, with the exception of vitamin B12. Vitamin/mineral deficiencies were counter-intuitively not associated with a (higher) grade of histological intestinal damage or (impaired) nutritional status. In conclusion, vitamin/mineral deficiencies are still common in newly "early diagnosed" CD-patients, even though the prevalence of obesity at initial diagnosis is rising. Extensive nutritional assessments seem warranted to guide nutritional advices and follow-up in CD treatment.

Malabsorption and nutritional balance in the ICU: fecal weight as a biomarker: a prospective observational pilot study.

INTRODUCTION: Malabsorption, which is frequently underdiagnosed in critically ill patients, is clinically relevant with regard to nutritional balance and nutritional management. We aimed to validate the diagnostic accuracy of fecal weight as a biomarker for fecal loss and additionally to assess fecal macronutrient contents and intestinal absorption capacity in ICU patients. METHODS: This was an observational pilot study in a tertiary mixed medical-surgical ICU in hemodynamically stable adult ICU patients, without clinically evident gastrointestinal malfunction. Fecal weight (grams/day), fecal energy (by bomb calorimetry in kcal/day), and macronutrient content (fat, protein, and carbohydrate in grams/day) were measured. Diagnostic accuracy expressed in terms of test sensitivity, specificity, positive (PPV) and negative predictive value (NPV), and receiver operator curves (ROCs) were calculated for fecal weight as a marker for energy malabsorption. Malabsorption was a priori defined as < 85% intestinal absorption capacity. RESULTS: Forty-eight patients (63 ± 15 years; 58% men) receiving full enteral feeding were included. A cut-off fecal production of > 350 g/day (that is, diarrhea) was linked to the optimal ROC (0.879), showing a sensitivity and PPV of 80%, respectively. Specificity and NPV were both 96%. Fecal weight (grams/day) and intestinal energy-absorption capacity were inversely correlated (r = -0.69; P < 0.001). Patients with > 350 g feces/day had a significantly more-negative energy balance compared with patients with < 350 g feces/day (loss of 627 kcal/day versus neutral balance; P = 0.012). CONCLUSIONS: A fecal weight > 350 g/day in ICU patients is a biomarker applicable in daily practice, which can act as a surrogate for fecal energy loss and intestinal energy absorption. Daily measurement of fecal weight is a feasible means of monitoring the nutritional status of critically ill patients and, in those identified as having malabsorption, can monitor responses to changes in dietary management.