Incidence, Diagnosis and Management of Malabsorption Following Oesophagectomy: a Systematic Review.

BACKGROUND: Survival following oesophagectomy for cancer is improving, resulting in increased focus on quality of life and survivorship. Malabsorption syndrome is multifactorial and includes exocrine pancreatic insufficiency (EPI), small intestinal bacterial overgrowth (SIBO) and bile acid malabsorption (BAM). The aim of this study was to evaluate the reported incidence and management of malabsorption syndromes post-oesophagectomy. METHODS: A systematic search of PubMed, EMBASE, MEDLINE, Scopus and the Cochrane Library evaluating incidence, diagnosis and management of malabsorption was performed for studies published until December 2021. RESULTS: Of 464 identified studies, eight studies (n = 7 non-randomised longitudinal studies) were included where patients were identified with malnutrition following oesophagectomy. Studies included a combined sample of 328 (range 7-63) patients. Malabsorption syndromes including EPI, SIBO and BAM occurred in 15.9-100%, 37.8-100% and 3.33-100% over 21 days-60 months, 1-24 months and 1-24 months respectively. There was no consensus definition for EPI, SIBO or BAM, and there was variation in diagnostic methods. Diagnostic criteria varied from clinical (gastrointestinal symptoms or weight loss), or biochemical (faecal elastase, hydrogen breath test and Selenium-75-labelled synthetic bile acid measurements). Treatment modalities using pancreatic enzyme replacement, rifaximin or colesevelam showed improvement in symptoms and weight in all studies, where investigated. CONCLUSIONS: Malabsorption syndromes following oesophagectomy are under-recognised, and thus under-reported. The resultant gastrointestinal symptoms may have a negative effect on post-operative quality of life. Current literature suggests benefit with outlined therapies; however, greater understanding of these conditions, their diagnosis and management is required to further understand which patients will benefit from treatment.

Valid Assessment of Carbohydrate Intolerance and the Need for a Distinction to Carbohydrate Malabsorption. Comment on "Roles of Lactose and Fructose Malabsorption and Dietary Outcomes in Children Presenting with Chronic Abdominal Pain.", Nutrients, 2019, 11, 3063.

We have read with interest the recent paper by Posovszky and Roesler et al [1] that reports, based on the doctoral thesis by Dr. Roesler [2] [...].

Preparing the Patient for Home Parenteral Nutrition and for a Successful Course of Therapy.

Preparing the patient for home parenteral nutrition (HPN) is a collaborative effort among many different clinicians. Identifying patients who will transition home with parenteral nutrition (PN) as early as possible allows for a thoughtful and safe approach. Communication regarding the HPN goals is critical to the patient's success, whether the requirement for PN is temporary or permanent. Management of these complex patients is best served by a multidisciplinary team with expertise in the area of nutrition support. Adherence to available guidelines that define best practice is imperative in all aspects of care for the patient on HPN.

The Oley Foundation and Consumer Support Groups.

Patients with intestinal failure (IF) often require home parenteral and/or enteral nutrition (HPEN). There are many complications associated with both IF and the use of HPEN, including infection and intolerance. Psychosocial effects, such as depression, isolation, fatigue, anxiety, financial stress, are also associated with IF and HPEN and can be difficult to address. Support groups offer patients and caregivers the opportunity to talk to and learn from others who have had similar experiences. The Oley Foundation, a nonprofit organization for HPEN consumers, caregivers, and clinicians, fulfills the role of a traditional support group while offering many other resources and programs.

Animal Models of Undernutrition and Enteropathy as Tools for Assessment of Nutritional Intervention.

: Undernutrition is a major public health problem leading to 1 in 5 of all deaths in children under 5 years. Undernutrition leads to growth stunting and/or wasting and is often associated with environmental enteric dysfunction (EED). EED mechanisms leading to growth failure include intestinal hyperpermeability, villus blunting, malabsorption and gut inflammation. As non-invasive methods for investigating gut function in undernourished children are limited, pre-clinical models are relevant to elucidating the pathophysiological processes involved in undernutrition and EED, and to identifying novel therapeutic strategies. In many published models, undernutrition was induced using protein or micronutrient deficient diets, but these experimental models were not associated with EED. Enteropathy models mainly used gastrointestinal injury triggers. These models are presented in this review. We found only a few studies investigating the combination of undernutrition and enteropathy. This highlights the need for further developments to establish an experimental model reproducing the impact of undernutrition and enteropathy on growth, intestinal hyperpermeability and inflammation, that could be suitable for preclinical evaluation of innovative therapeutic intervention.

Assessment of Machine Learning Detection of Environmental Enteropathy and Celiac Disease in Children.

Importance: Duodenal biopsies from children with enteropathies associated with undernutrition, such as environmental enteropathy (EE) and celiac disease (CD), display significant histopathological overlap. Objective: To develop a convolutional neural network (CNN) to enhance the detection of pathologic morphological features in diseased vs healthy duodenal tissue. Design, Setting, and Participants: In this prospective diagnostic study, a CNN consisting of 4 convolutions, 1 fully connected layer, and 1 softmax layer was trained on duodenal biopsy images. Data were provided by 3 sites: Aga Khan University Hospital, Karachi, Pakistan; University Teaching Hospital, Lusaka, Zambia; and University of Virginia, Charlottesville. Duodenal biopsy slides from 102 children (10 with EE from Aga Khan University Hospital, 16 with EE from University Teaching Hospital, 34 with CD from University of Virginia, and 42 with no disease from University of Virginia) were converted into 3118 images. The CNN was designed and analyzed at the University of Virginia. The data were collected, prepared, and analyzed between November 2017 and February 2018. Main Outcomes and Measures: Classification accuracy of the CNN per image and per case and incorrect classification rate identified by aggregated 10-fold cross-validation confusion/error matrices of CNN models. Results: Overall, 102 children participated in this study, with a median (interquartile range) age of 31.0 (20.3-75.5) months and a roughly equal sex distribution, with 53 boys (51.9%). The model demonstrated 93.4% case-detection accuracy and had a false-negative rate of 2.4%. Confusion metrics indicated most incorrect classifications were between patients with CD and healthy patients. Feature map activations were visualized and learned distinctive patterns, including microlevel features in duodenal tissues, such as alterations in secretory cell populations. Conclusions and Relevance: A machine learning-based histopathological analysis model demonstrating 93.4% classification accuracy was developed for identifying and differentiating between duodenal biopsies from children with EE and CD. The combination of the CNN with a deconvolutional network enabled feature recognition and highlighted secretory cells' role in the model's ability to differentiate between these histologically similar diseases.

Dietary and symptom assessment in adults with self-reported non-coeliac gluten sensitivity.

BACKGROUND & AIMS: The mechanisms behind non-coeliac gluten sensitivity (NCGS) are not fully understood although clinical symptoms have shown to subside after wheat withdrawal. Self-prescription of a gluten-free diet (GFD) without medical supervision is common in NCGS subjects, resulting in dietary restrictions that can cause macro- and micronutrient deficiencies. The primary aim was to describe dietary intake, including FODMAP, in subjects with self-reported gluten sensitivity on GFD in whom coeliac disease (CD) and wheat allergy were excluded. Secondary, clinical symptoms and health-related quality of life (HR-QoL) were examined. METHODS: Baseline characteristics were obtained from 65 adults with self-reported NCGS on GFD recruited to a randomised placebo-controlled challenge trial at Oslo University Hospital. Dietary intake was obtained by a seven-day food record and symptoms recorded by questionnaires. RESULTS: Mean proportions of energy were 43 E% from fat, 40 E% from carbohydrate and 17 E% from protein. Intakes of vitamin D, folic acid, calcium, iodine and iron were lower than recommended, mean (SD) 7.3 (5.8) µg, 235 (105) µg, 695 (309) mg, 81 (52) µg and 9.6 (7.5) mg, respectively. Mean (SD) intake of FODMAP was 11.6 g (8.7). Gastrointestinal symptoms as scored by 100 mm visual analogue scale (VAS) were all below 15 mm of which wind and bloating were the most expressed. Tiredness, concentration difficulties, fatigue and muscle/joint pain were scored highest among extra-intestinal symptoms. Gastrointestinal symptoms as scored by gastrointestinal symptom rating scale - irritable bowel syndrome version (GSRS-IBS) were correlated with mild depression (r = 0.43) and inversely correlated with five sub-domains of HR-QoL (-0.29 < r < -0.26). CONCLUSION: Subjects with self-reported NCGS on GFD had high proportion of energy from fat and sub-optimal intakes of vitamin D, folic acid, calcium, iodine and iron. Despite GFD and moderate intake of FODMAP, the subjects reported various gastro- and extra-intestinal symptoms and reduced HR-QoL. The findings highlight the importance of dietary education and nutritional follow-up of subjects on GFD.

The impact of home parenteral nutrition on the burden of disease including morbidity, mortality and rate of hospitalisations.

INTRODUCTION: Home parenteral nutrition (HPN) provides fluid and nutrition essential for the survival of patients with type 3 intestinal failure (IF). However, it is associated with complications and re-admission to hospital. This study aims to investigate the effect of HPN on mortality, morbidity and hospital re-admissions. METHOD: This is a retrospective cohort study. All patients newly dependent on HPN discharged over a 4-year period between 2011 and 2015 were included. Patients' characteristics, nutritional status and diagnosis were recorded, along with frequency and duration of HPN administration. Outcomes collected included hospital re-admissions, morbidity, catheter related blood stream infections (CRBSIs) and mortality. Regression analyses were performed to estimate the rate of different outcomes adjusted for prognostic factors. RESULTS: There were 210 patients included, 561 separate HPN prescriptions equating to 110,537 catheter days. Total number of deaths was 44 (0.398 deaths per 1000 catheter days). There were 196 re-admissions to hospital recorded for a total of 5594 days, 69 (33%) of these re-admissions were unplanned (2484 days in hospital). Principle reasons for unplanned re-admissions included: CRBSIs (n = 31, 45%); other sepsis (n = 10, 14.5%) and abdominal symptoms (n = 9, 13%). CRBSIs were recorded in 22 (10%) patients, equating to a rate of 0.199 per 1000 catheter days. Days per week on HPN increased the relative rate (RR) of time in hospital due to any reason or for unplanned readmissions, RR 1.50 (95% CI: 1.26, 1,78 p < 0.001) and RR 1.39 (95% CI: 1.10, 1.75 p = 0.006) respectively. However, there was no association between days per week on HPN and CRBSI occurrence. CONCLUSION: Unplanned re-admissions for patients with IF accounted for a third of all hospitalisations in those on HPN and the majority were due to CRBSI. The number of HPN dependent days per week was related to all-cause unplanned re-admissions, although not to CRBSI rate.

[Assessment of a digestive malabsorption syndrome]. / Vignette diagnostique de l'étudiant. Exploration d'un syndrome de malabsorption digestive.

Malabsorption syndrome is a complex clinical entity that needs to be carefully explored. Patients present frequently chronic diarrhoea associated with weight loss. These symptoms affect patient's quality of life. The assessment of this syndrome requires a detailed anamnesis, a careful clinical exam, the use of biological measurements in both blood and faeces, and, if necessary, other more complex investigations including radionuclide tests. It is important to find the right pathogenesis in order to start effective treatments if possible. First, there are classical bowel pathologies like celiac disease and rarely Crohn disease. Second, biliopancreatic pathologies may also result in a malabsorption syndrome. Of note, this syndrome is very common after abdominal surgery like intestinal resection following mesenteric ischemia, biliopancreatic and gastric surgery. We will use a clinical case of malabsorption after an abdominal surgery to illustrate how to explore these patients who are suffering from malabsorption.

Le syndrome de malabsorption est une entité clinique, rencontrée régulièrement en consultation, qui combine des symptômes digestifs et généraux. Il se caractérise essentiellement par des troubles du transit (diarrhée chronique), associés fréquemment à une perte de poids. Cette symptomatologie altère la qualité de vie des patients, il est donc important de mettre au point le/les mécanisme(s) responsable(s) de la malabsorption afin de pouvoir envisager les différentes possibilités thérapeutiques et améliorer au maximum la qualité de vie du patient. Pour ce faire, nous devons, dans un premier temps, procéder à une anamnèse minutieuse et un examen clinique soigné, ensuite prescrire et exploiter les analyses de laboratoire (sur sang et sur selles) adaptées ainsi que les examens complémentaires de médecine nucléaire, d'imagerie médicale et d'endoscopie digestives. Il existe tout d'abord, une série de pathologies gastro-intestinales qui présentent ce syndrome, telles que la maladie coeliaque dans sa forme classique et, plus rarement, la maladie de Crohn ainsi que les pathologies bilio-pancréatiques. Le syndrome de malabsorption est également très fréquent dans les suites de chirurgies digestives lourdes telles que l'ischémie mésentérique entraînant un syndrome de grêle court, la pancréatectomie partielle ou totale, la gastrectomie totale, ainsi que les chirurgies du système biliaire. Nous allons, au travers d'un cas clinique, illustrer l'approche diagnostique sur le plan anamnestique, clinique et technique d'une malabsorption secondaire à une chirurgie digestive.

The active problem solving of patients dependent on home parenteral nutrition: A qualitative analysis.

BACKGROUND & AIMS: People with chronic, type 3, intestinal failure often require long-term home parenteral nutrition (HPN). People receiving HPN have frequent interactions with their healthcare, due to the need for close monitoring and due to recurrent hospital admissions. Individuals' responses to, and interactions with, their health care service provides are poorly described. We conducted a service evaluation to explore people's experiences of HPN-related healthcare interactions in order to identify how service providers can best meet the individualised needs of patients. METHODS: We interviewed ten people receiving HPN. The participants were asked about their healthcare interactions related to HPN. The data were analysed using a qualitative research method known as interpretive phenomenological analysis. This analytical approach is concerned with the meaning that people ascribe to particular events, in this case their HPN-related healthcare interactions. RESULTS: The participants in this study described a range of psychosocial problems related to their HPN healthcare interactions, including reliance, risk and restrictions. Participants' solutions to these problems included adaptation of their routine, self-guardianship and passivity. Sometimes, these solutions generated secondary problems of their own, including concerns with resource use, negative healthcare interactions and conflicts of responsibility. A range of contextual factors influenced how participants interpreted their healthcare interactions and the solutions available to them. These contextual factors included continuity of healthcare professionals, the attitude of staff, and information and knowledge about HPN. CONCLUSIONS: By attending to the individual meaning ascribed to healthcare events, and the contextual factors that surround these events, we have been able to better understand the decisions made by patients dependent on HPN. This suggests that healthcare professionals may also better understand their patients' decision making by attending to the individual meaning that patients ascribe to healthcare events and to contextual factors. We propose a model to describe the process of problem -> resolution -> problem in which participants are actively engaged.

Eficacia y seguridad del uso de colestiramina en el tratamiento de diarrea cronica con malabsorción de acidos biliares / Efficacy and safety of the use of cholestyramine in the treatment of chronic diarrhea with bile acid malabsorption

INTRODUCCIÓN: Antecedentes: El presente dictamen presenta la evaluación de la eficacia y seguridad del uso de colestiramina en el tratamiento de diarrea crónica asociada a malabsorción de ácidos biliares en niños. Aspectos Generales: La diarrea crónica es el signo principal de la malabsorción de ácidos biliares (MAB), la cual se produce por un desbalance en la homeostasis de estos ácidos en la circulación enterohepática. Los ácidos biliares recirculan entre el hígado y el intestino delgado a través del sistema de circulación enterohepática. Este sistema permite la absorción de grasas en el intestino delgado y la reabsorción de los ácidos biliares en el íleon terminal. Tecnología Sanitaria de Interés: La colestiramina es un secuestrador de ácidos liliares. Esta consta de resinas no digeribles cargadas positivamente que se unen a los ácidos biliares en el intestino, y permiten su excreción en las heces en forma de complejos insolubles. Así, evita que los ácidos biliares se acumulen en el colon y provoquen desbalance hídrico y diarrea. METODOLOGIA: Estrategia de Búsqueda: Se llevó a cabo una busqueda de la literatura con respecto a la eficacia y seguridad de colestiramina en el tratamiento de diarrea crónica en la bases de datos de PubMed, Tripdatase y www.clinicaltrials.gov. RESULTADOS: Sinopsis de la Evidencia: Se llevó a cabo una búsqueda de evidencia científica relacionada al uso de colestiramina en el tratamiento de pacientes con diarrea crónica asociada a malabsorción de ácidos biliares. En la presente sinopsis se describe la evidencia disponible según el tipo de publicación, siguiendo lo indicado en los criterios de elegibilidad (Guias de Práctica Clínica, Evaluación de Tecnologías en Salud, Revisiones Sistemáticas, Resúmenes de Artículos, MA, ECA fase III). CONCLUSIONES: A la fecha (octubre 2016) no se han llevado a cabo ensayos clínicos aleatorizados que evalúen la eficacia y seguridad del uso de colestiramina en pacientes pediátricos o adultos con diarrea crónica ocasionada por la malabsorción de ácidos biliares. Los resultados reportados en el presente dictamen preliminar corresponden a cuatro GPC, una revisión sistemática basada en estudios observacionales y el resumen de un estudio retrospectivo que evalúa la respuesta al tratamiento con colestiramina en pacientes adultos con diarrea crónica acuosa. El Instituto de Evaluación de Tecnologias en Salud e Investigación (IETSI) aprueba el uso de colestiramina como alternativa de tratamiento en pacientes con diarrea crónica por ácidos biliares. En el periodo de vigencia de este dictamen es de un año y la continuación de dicha aprobación estará sujeta a los resultados obtenidos de los pacientes que se beneficien con dicho tratamiento y a nueva evidencia que pueda surgir en el tiempo.

Assessment of intestinal malabsorption.

Significant efforts have been made in the last decade to either standardize the available tests for intestinal malabsorption or to develop new, more simple and reliable techniques. The quest is still on and, unfortunately, clinical practice has not dramatically changed. The investigation of intestinal malabsorption is directed by the patient's history and baseline tests. Endoscopy and small bowel biopsies play a major role although non-invasive tests are favored and often performed early on the diagnostic algorithm, especially in paediatric and fragile elderly patients. The current clinically available methods and research tools are summarized in this review article.

Severe intestinal malabsorption associated with olmesartan: a French nationwide observational cohort study.

OBJECTIVES: Severe sprue-like enteropathy associated with olmesartan has been reported, but there has been no demonstration of an increased risk by epidemiological studies. AIM: To assess, in a nationwide patient cohort, the risk of hospitalisation for intestinal malabsorption associated with olmesartan compared with other angiotensin receptor blockers (ARB) and ACE inhibitors (ACEIs). DESIGN: From the French National Health Insurance claim database, all adult patients initiating ARB or ACEI between 1 January 2007 and 31 December 2012 with no prior hospitalisation for intestinal malabsorption, no serology testing for coeliac disease and no prescription for a gluten-free diet product were included. Incidence of hospitalisation with a discharge diagnosis of intestinal malabsorption was the primary endpoint. RESULTS: 4 546 680 patients (9 010 303 person-years) were included, and 218 events observed. Compared with ACEI, the adjusted rate ratio of hospitalisation with a discharge diagnosis of intestinal malabsorption was 2.49 (95% CI 1.73 to 3.57, p<0.0001) in olmesartan users. This adjusted rate ratio was 0.76 (95% CI 0.39 to 1.49, p=0.43) for treatment duration shorter than 1 year, 3.66 (95% CI 1.84 to 7.29, p<0.001) between 1 and 2 years and 10.65 (95% CI 5.05 to 22.46, p<0.0001) beyond 2 years of exposure. Median length of hospital stay for intestinal malabsorption was longer in the olmesartan group than in the other groups (p=0.02). Compared with ACEI, the adjusted rate ratio of hospitalisation for coeliac disease was 4.39 (95% CI 2.77 to 6.96, p<0.0001) in olmesartan users and increased with treatment duration. CONCLUSIONS: Olmesartan is associated with an increased risk of hospitalisation for intestinal malabsorption and coeliac disease.

Chronic unexplained diarrhea: a logical and cost-effective approach to assessment.

PURPOSE OF REVIEW: The workup of chronic unexplained diarrhea can be equally frustrating for care providers and patients. It carries a physical, financial, and social toll. In this review we provide a sensible approach to evaluating and managing chronic diarrhea. RECENT FINDINGS: Bile acid diarrhea is becoming increasingly recognized as a potential cause behind some cases of chronic diarrhea. SUMMARY: A detailed history and physical examination can provide clues that guide a logical approach to the evaluation. We suggest a cost-effective approach to the workup and management of chronic diarrhea based on individual patient factors related to clinical history and physical exam. We find that this approach leads to initiation of treatment in a time-efficient fashion and avoids unnecessary testing.

Food, fibre, bile acids and the pelvic floor: An integrated low risk low cost approach to managing irritable bowel syndrome.

Patients presenting with abdominal pain and diarrhea are often labelled as suffering from irritable bowel syndrome, and medications may be used often without success. Advances in the understanding of the causes of the symptoms (including pelvic floor weakness and incontinence, bile salt malabsorption and food intolerance) mean that effective, safe and well tolerated treatments are now available.

Medication absorption for patients with an ileostomy.

The Association of Stoma Care Nurses UK (2013) has stressed that it is the role of the stoma care nurse to provide education to patients, carers, prescribers and other nurses. This includes the area of medication management. Ensuring patients with an ileostomy receive their medication in a form they can absorb is of importance to every stoma care nurse. Prescribing for patients with a stoma calls for special care. Each patient with an ileostomy requires assessment of their medication regimen for the purpose of identifying potential medical absorption issues. However, from an extensive literature search, it is evident that there is very little literature published on this subject. This article looks at the considerations to take into account when prescribing medication for ileostomy patients, and examines the results of a clinical audit on medication prescribers' knowledge of the impact of ileostomy formation on the absorption of medication.

Safety assessment of FDA-approved (orlistat and lorcaserin) anti-obesity medications.

INTRODUCTION: Options for treating obesity remain limited despite it being a chronic, recurrent and morbid condition. New drugs that are proposed for its treatment encounter strong reluctance by regulatory agencies and many doctors. AREAS COVERED: This review will focus on the safety of an older drug, orlistat (the only one still approved in the European Union) and a newer recently FDA-approved one, lorcaserin. Both are approved as long-term monotherapy for obesity in the United States of America and they have demonstrated median weight loss of nearly 3% over placebo. EXPERT OPINION: Research, development and approval of new anti-obesity drugs are necessary for improved management of this chronic condition. Orlistat and lorcaserin are two FDA-approved drugs with limited overall efficacy. Nevertheless they are useful weapons for at least some obese individuals. Orlistat has a long and solid safety profile, whereas the safety of lorcaserin is still a matter of debate, mainly due to a lack of long-term data. However, lorcaserin's selective agonism on 5HT2c serotonin receptors diminishes concerns about valvulopathy associated with other serotonin agonists, such as fenfluramine.

Long-term medical complications after malabsorptive procedures: effects of a late clinical nutritional intervention.

OBJECTIVE: The growing prevalence of severe obesity, combined with the failure of conservative treatments, has led to a significant spread of bariatric surgical procedures. The aim of this study was to emphasize the need of adequate presurgery patient selection and close follow-up after malabsorptive procedures for bariatric surgery. METHODS: The study retrospectively evaluated 25 (20 F, 5 M; mean age 43 ± 13 y) obese patients (mean weight before intervention 134 ± 30.7 kg, body mass index 50.7 ± 10.1 kg/m(2)) attending our outpatient clinical nutrition unit for severe malabsorption and secondary malnutrition after surgical intervention that had been performed outside the regional area. RESULTS: All patients received personalized dietetic indications; in 12 of 25 (48%) cases integrated by oral protein supplements and in 5 of 25 (20%) by medium chain triglycerides. According to screening exams, patients were prescribed oral/parenteral iron, vitamins A, B group, D, and folate supplementation. In 14 of 25 (56%) patients, parenteral hydration and in 4 of 25 (16%), long-term parenteral nutrition was required. Five patients required hospitalization for severely complicated protein-energy malnutrition. CONCLUSION: Nutritional deficiencies are common after malabsorptive procedures for bariatric surgery; these can be present or latent before surgery, frequently going unrecognized and/or inadequately treated particularly when patients are not strictly followed up by the operating center. Despite the adequate-even intensive-intervention, clinical nutritional status moderately improved in all patients.

SeHCAT [tauroselcholic (selenium-75) acid] for the investigation of bile acid malabsorption and measurement of bile acid pool loss: a systematic review and cost-effectiveness analysis.

BACKGROUND: The principal diagnosis/indication for this assessment is chronic diarrhoea due to bile acid malabsorption (BAM). Diarrhoea can be defined as the abnormal passage of loose or liquid stools more than three times daily and/or a daily stool weight > 200 g per day and is considered to be chronic if it persists for more than 4 weeks. The cause of chronic diarrhoea in adults is often difficult to ascertain and patients may undergo several investigations without a definitive cause being identified. BAM is one of several causes of chronic diarrhoea and results from failure to absorb bile acids (which are required for the absorption of dietary fats and sterols in the intestine) in the distal ileum. OBJECTIVE: For people with chronic diarrhoea with unknown cause and in people with Crohn's disease and chronic diarrhoea with unknown cause (i.e. before resection): (1) What are the effects of selenium-75-homocholic acid taurine (SeHCAT) compared with no SeHCAT in terms of chronic diarrhoea, other health outcomes and costs? (2) What are the effects of bile acid sequestrants (BASs) compared with no BASs in people with a positive or negative SeHCAT test? (3) Does a positive or negative SeHCAT test predict improvement in terms of chronic diarrhoea, other health outcomes and costs? DATA SOURCES: A systematic review was conducted to summarise the evidence on the clinical effectiveness of SeHCAT for the assessment of BAM and the measurement of bile acid pool loss. Search strategies were based on target condition and intervention, as recommended in the Centre for Reviews and Dissemination (CRD) guidance for undertaking reviews in health care and the Cochrane Handbook for Diagnostic Test Accuracy Reviews. The following databases were searched up to April 2012: MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations; EMBASE; the Cochrane Databases; Database of Abstracts of Reviews of Effects; Health Technology Assessment (HTA) Database; and Science Citation Index. Research registers and conference proceedings were also searched. REVIEW METHODS: Systematic review methods followed the principles outlined in the CRD guidance for undertaking reviews in health care and the National Institute for Health and Care Excellence (NICE) Diagnostic Assessment Programme interim methods statement. In the health economic analysis, the cost-effectiveness of SeHCAT for the assessment of BAM, in patients with chronic diarrhoea, was estimated in two different populations. The first is the population of patients with chronic diarrhoea with unknown cause and symptoms suggestive of diarrhoea-predominant irritable bowel syndrome (IBS-D) and the second population concerns patients with Crohn's disease without ileal resection with chronic diarrhoea. For each population, three models were combined: (1) a short-term decision tree that models the diagnostic pathway and initial response to treatment (first 6 months); (2) a long-term Markov model that estimates the lifetime costs and effects for patients initially receiving BAS; and (3) a long-term Markov model that estimates the lifetime costs and effects for patients initially receiving regular treatment (IBS-D treatment in the first population and Crohn's treatment in the second population). Incremental cost-effectiveness ratios were estimated as additional cost per additional responder in the short term (first 6 months) and per additional quality-adjusted life-year (QALY) in the long term (lifetime). RESULTS: We found three studies assessing the relationship between the SeHCAT test and response to treatment with cholestyramine. However, the studies had small numbers of patients with unknown cause chronic diarrhoea, and they used different cut-offs to define BAM. For the short term (first 6 months), when trial of treatment is not considered as a comparator, the optimal choice depends on the willingness to pay for an additional responder. For lower values (between £1500 and £4600) the choice will be no SeHCAT in all scenarios; for higher values either SeHCAT 10% or SeHCAT 15% becomes cost-effective. For the lifetime perspective, the various scenarios showed widely differing results: in the threshold range of £20,000-30,000 per QALY gained we found as optimal choice either no SeHCAT, SeHCAT 5% (only IBS-D) or SeHCAT 15%. When trial of treatment is considered a comparator, the analysis showed that for the short term, trial of treatment is the optimal choice across a range of scenarios. For the lifetime perspective with trial of treatment, again the various scenarios show widely differing results. Depending on the scenario, in the threshold range of £20,000-30,000 per QALY gained, we found as optimal choice either trial of treatment, no SeHCAT or SeHCAT 15%. CONCLUSIONS: In conclusion, the various analyses show that for both populations considerable decision uncertainty exists and that no firm conclusions can be formulated about which strategy is optimal. Standardisation of the definition of a positive SeHCAT test should be the first step in assessing the usefulness of this test. As there is no reference standard for the diagnosis of BAM and SeHCAT testing provides a continuous measure of metabolic function, diagnostic test accuracy (DTA) studies are not the most appropriate study design. However, in studies where all patients are tested with SeHCAT and all patients are treated with BASs, response to treatment can provide a surrogate reference standard; further DTA studies of this type may provide information on the ability of SeHCAT to predict response to BASs. A potentially more informative option would be multivariate regression modelling of treatment response (dependent variable), with SeHCAT result and other candidate clinical predictors as covariates. Such a study design could also inform the definition of a positive SeHCAT result. STUDY REGISTRATION: The study is registered as PROSPERO CRD42012001911. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Bariatric and metabolic surgery.

In the beginning of the 21st century obesity still represents health, social and economical threat for most of economically wealthy countries worldwide. Estimated direct costs for obesity and related comorbidities treatment exceed 5% of the total health care costs both in the US and in European Union. However, in addition there are obesity-related indirect costs linked to more frequent work sickness leave, higher unemployment rates and overall lower productivity of obese patients. Surgical treatment of obesity (bariatric surgery) is the most effective long-term treatment modality for those patients suffering from higher degrees of obesity. Bariatric surgery has not only positive effects on weight loss, but is also extremely effective in improving or resolving many of obesity-related comorbidities, which have evolved rapidly into the so-called metabolic surgery. T2DM may serve as excellent example of metabolic, obesity-related comorbidity which can be treated with bariatric-metabolic procedure even without direct relation to weight loss. In such cases bariatric surgery evolves into metabolic surgery. Thus metabolic operations (namely from the malabsorptive end) deeply influence hormonal secretion especially in the proximal part of small bowel, change parametres of entero-insular axis and have positive influence on insulin secretion, sensitivity and on the entire complex of glucose tolerance. Nowadays we can witness dramatic changes in perception of T2DM from bariatric surgeons, diabetologists, and many other medical specialists. T2DM has evolved from primarily medical disease into a condition where surgeons may play a more active role in the management of the diabetic patient. However, it has to be stressed that metabolic treatment of T2DM and other metabolic disorders need multidisciplinary approach and collaboration and that surgeon should play very important role as a multidisciplinary team member, however metabolic surgery should not yet be considered as stand-alone treatment modality.