Prevalence of small intestinal bacterial overgrowth in intestinal failure syndrome: A systematic review and meta-analysis.

BACKGROUND AND AIM: Patients with intestinal failure (IF) have abnormal intestinal anatomy, secretion, and dysmotility, which impairs intestinal homeostatic mechanisms and may lead to small intestinal bacterial overgrowth (SIBO). We conducted a systematic review and meta-analysis to determine the prevalence of SIBO in patients with IF and to identify risk factors for SIBO. METHODS: MEDLINE (PubMed) and Embase electronic databases were searched from inception to December 2023 for studies that reported the prevalence of SIBO in IF. The prevalence rates, odds ratio (OR), and 95% confidence intervals of SIBO in IF and the risk factors for SIBO in IF were calculated using random effects model. RESULTS: Final dataset included nine studies reporting on 407 patients with IF. The prevalence of SIBO in IF was 57.5% (95% CI 44.6-69.4), with substantial heterogeneity in this analysis (I2 = 80.9, P = 0.0001). SIBO prevalence was sixfold higher in patients with IF who received parenteral nutrition (PN) compared with IF patients not on PN (OR = 6.0, 95% CI 3.0-11.9, P = 0.0001). Overall, the prevalence of SIBO in patients with IF using PPI/acid-suppressing agents (72.0%, 95% CI 57.5-83.8) was numerically higher compared with IF patients not using these agents (47.6%, 95% CI 25.7-70.2). CONCLUSIONS: This systematic review and meta-analysis suggests that there is an increased risk of SIBO in patients with IF and that PN, and potentially, the use of PPI/acid-suppressing agents is risk factors for SIBO development in patients with IF. However, the quality of evidence is low and can be attributed to lack of case-control studies and clinical heterogeneity seen in the studies.

The Adult Carbohydrate Perception Questionnaire Identifies Patients with Lactose or Fructose Intolerance Who Respond to Diet.

INTRODUCTION: There is no evidence that a positive breath test is a good predictor of the success of a carbohydrate-restricted diet. Our objective was to investigate whether patients in whom lactose intolerance (LIT) or fructose intolerance (FIT) is diagnosed by validated symptom measurement respond to diet. METHODS: Patients referred for evaluation of LIT or FIT underwent hydrogen/methane breath testing (malabsorption test) and symptom measurement with the adult Carbohydrate Perception Questionnaire (aCPQ, intolerance test) before and after 50 g lactose or 25 g fructose. Patients with a positive aCPQ received instructions on specific diets and supplements. Severity of abdominal pain, bloating, diarrhoea, flatulence, and nausea were measured using a visual analogue scale (VAS) before (VAS1, mm) and after (VAS2, mm) diet. The change in VAS for individual symptoms and overall symptoms after diet is expressed as deltaVAS (mm) and as change relative to VAS1 (%). RESULTS: Forty-one patients were included (23 LIT, 8 FIT, 10 LIT+FIT). Eight patients had negative breath tests (no malabsorption). After 2 months of diet, the overall VAS and the individual symptoms decreased (p < 0.001). Overall VAS1 and the VAS1 for individual symptoms correlated significantly with the decrease in deltaVAS (mm) after diet. Nineteen patients (46%) had total recovery, and additional 13 patients (32%) had improvement of >50%. Response to diet was independent of breath test results. CONCLUSION: This uncontrolled and unblinded study suggests that patients with carbohydrate intolerance diagnosed by aCPQ benefit significantly from diet, independent of the presence of malabsorption. Controlled studies are required to confirm these results in larger patient groups.

Validation of the Structured Assessment of Gastrointestinal Symptoms Scale to Support Standardized Evaluation and Follow-up.

OBJECTIVES: Patient-reported outcome measures facilitate evaluation of patients and allow to better assess treatment effects. Validated tools are lacking for pediatric gastroenterological patients. We thus aimed to adapt and validate for pediatric populations a self-administered Structured Assessment of Gastrointestinal Symptoms (SAGIS) tool that previously has been validated in adult cohorts. METHODS: Each item of the original SAGIS instrument was thoroughly reviewed for its relevance in the pediatric population. The resulting pediatric (p)SAGIS was utilized over a 35 months' period in consecutive patients in a pediatric outpatient GI clinic. Principal component analysis (PCA) followed by varimax rotation and confirmatory factor analysis (CFA) was performed in derivation and validation samples. Responsiveness to change was assessed in 32 children with inflammatory bowel disease (IBD) after 12 months of therapy. RESULTS: The final pediatric SAGIS (pSAGIS) consisted of 21 GI-related Likert-type questions, 8 dichotomous questions assessing extra-intestinal symptoms, and 2 most bothersome symptoms; 1153 children/adolescents completed a total of 2647 questionnaires. Cronbach alpha was 0.89, indicating good internal consistency. PCA supported a 5-factor model (symptom groups: abdominal pain, dyspepsia, diarrhea, constipation, dysphagia/nausea) and CFA showed good model fit (comparative fit index: 0.96, root-mean-square error of approximation: 0.075). The initial mean total GI symptom score in IBD patients (8.7 ± 10.3) decreased to 3.6 ± 7.7 after 1 year of therapy ( P < 0.01), and 4 of 5 symptom group scores decreased significantly upon treatment ( P < 0.05). CONCLUSIONS: The pSAGIS is a novel, easy to use, self-administered instrument for GI-symptom assessment in children/adolescents with excellent psychometric properties. It may standardize GI-symptom assessment and may enable uniform clinical analysis of treatment outcomes.

Coordinated Multi-Language Translation of A Validated Symptom Questionnaire for Carbohydrate Intolerances: A Practical Structured Procedure.

BACKGROUND AND AIMS: Validated questionnaires help to minimize diagnostic bias, to standardize symptom assessment and to achieve comparability between studies and centers. In a recent European guideline the adult and the pediatric carbohydrate perception questionnaires (aCPQ and pCPQ), were recommended to be used for the diagnosis of carbohydrate intolerances in adult and pediatric patients. The implementation of this guideline into clinical practice makes availability of validated translations a necessity. METHODS: Clinical experts who recognized the need for these questionnaires to be available in their own language participated in the translation process. The tasks were assigned and a workflow following a predefined procedure based on recommendations of the Rome foundation was developed. The procedure had 5 phases: foundation, nomination, translation, revision, cognitive debriefing. RESULTS: Within eight months the aCPQ was translated into Bulgarian, French, Hungarian, Italian, Polish, Romanian, Russian and Slovenian language and the pCPQ into Dutch, French and Romanian. This expands the population which can be served with the aCPQ from 160 million to over 500 million Europeans. The reach of pCPQ expanded from 92 million to 193 million Europeans. CONCLUSIONS: We report the development and implementation of a centrally organized process of translation of validated questionnaires, following a predefined procedure based on recommendations of the Rome foundation. This structured procedure may aid future efforts to standardize and harmonize the translation of validated questionnaires.

Significance of validated symptom assessment versus breath testing for malabsorption after lactose load in children.

BACKGROUND AND OBJECTIVES: Lactose malabsorption and lactose-induced symptoms are poorly correlated, as shown by breath tests and various symptom assessment methods. Validated assessment is the key to overcome the limitations of biased symptom measurements. We characterized lactose-induced symptoms with the population-specific, validated paediatric carbohydrate perception questionnaire (pCPQ) and their correlation with the history of symptoms (HoS). METHODS: A total of 130 patients with functional gastrointestinal symptoms underwent a lactose hydrogen breath and tolerance test (LBTT) allowing for a diagnosis of malabsorption (M+) and lactose sensitivity (S+). HoS indicative of lactose-induced symptoms (abdominal pain, nausea, bloating, flatulence, diarrhoea) in the 4 weeks preceding the test was determined using a validated questionnaire. The pCPQ was used to score lactose-induced symptoms. MAIN RESULTS: The LBTT revealed 41 children (31.5%) with lactose malabsorption (M+), 56 (43.1%) with lactose sensitivity (S+) and 24 (18.5%) were M+/S+. Sensitivity correlated with HoS (P < 0.001), regardless of whether malabsorption was detectable. Malabsorption status did not correlate with HoS (NS). The odds of lactose sensitivity significantly increased when abdominal pain [odds ratio (OR) 3.5, confidence interval (CI) 1.6-7.8], nausea (OR 2.3, CI, 1.1-4.9) and flatulence (OR 3.1, CI 1.4-6.8) were reported in the 4 weeks preceding the LBTT. Symptoms after the lactose load were similar for M+/S+ and M-/S+, except for flatulence, which was more frequent in malabsorbers (P < 0.01). CONCLUSION: Our findings fit well with the emerging view of the important role of a validated symptom assessment after a lactose load. The determination of symptoms may be more relevant than malabsorption for the clinical outcomes of paediatric patients with lactose-related gastrointestinal symptoms.

European guideline on indications, performance, and clinical impact of hydrogen and methane breath tests in adult and pediatric patients: European Association for Gastroenterology, Endoscopy and Nutrition, European Society of Neurogastroenterology and Motility, and European Society for Paediatric Gastroenterology Hepatology and Nutrition consensus.

INTRODUCTION: Measurement of breath hydrogen (H2 ) and methane (CH4 ) excretion after ingestion of test-carbohydrates is used for different diagnostic purposes. There is a lack of standardization among centers performing these tests and this, together with recent technical developments and evidence from clinical studies, highlight the need for a European guideline. METHODS: This consensus-based clinical practice guideline defines the clinical indications, performance, and interpretation of H2 -CH4 -breath tests in adult and pediatric patients. A balance between scientific evidence and clinical experience was achieved by a Delphi consensus that involved 44 experts from 18 European countries. Eighty eight statements and recommendations were drafted based on a review of the literature. Consensus (≥80% agreement) was reached for 82. Quality of evidence was evaluated using validated criteria. RESULTS: The guideline incorporates new insights into the role of symptom assessment to diagnose carbohydrate (e.g., lactose) intolerances and recommends that breath tests for carbohydrate malabsorption require additional validated concurrent symptom evaluation to establish carbohydrate intolerance. Regarding the use of breath tests for the evaluation of oro-cecal transit time and suspected small bowel bacterial overgrowth, this guideline highlights confounding factors associated with the interpretation of H2 -CH4 -breath tests in these indications and recommends approaches to mitigate these issues. CONCLUSION: This clinical practice guideline should facilitate pan-European harmonization of diagnostic approaches to symptoms and disorders, which are very common in specialist and primary care gastroenterology practice, both in adult and pediatric patients. In addition, it identifies areas of future research needs to clarify diagnostic and therapeutic approaches.

Relevance of Methane and Carbon Dioxide Evaluation in Breath Tests for Carbohydrate Malabsorption in a Paediatric Cohort.

OBJECTIVES: The relevance of methane measurement in breath tests for the detection of carbohydrate malabsorption in children is controversial. The need for correction for poor sample collection is disputed. We evaluated the relevance of methane/CO2 measurements for the diagnosis of paediatric carbohydrate malabsorption. METHODS: A total of 132 breath tests (fructose: n = 54; lactose: n = 78) were performed in 91 children/adolescents with functional abdominal complaints. Breath samples were collected and analysed for hydrogen, methane, and CO2. Malabsorption was defined by a net increase over baseline of ≥20 parts per million (ppm) for hydrogen, ≥5 to ≥12 ppm for methane, and ≥10 to ≥15 ppm for hydrogen-plus-methane. The diagnosis was made before and after the use of a CO2-based correction factor (5.5% as the numerator). Hydrogen-based test results were compared with results obtained with other cut-off values. RESULTS: Fifty-eight positive tests were obtained by hydrogen measurement (without CO2 correction). The addition of methane measurements did not significantly influence the test results (P > 0.05). Only under the use of extraordinary cut-offs (combined hydrogen-plus-methane smaller than ≥18 ppm) did the rate of malabsorbers increase significantly (P < 0.05). After CO2 correction, hydrogen ≥20 ppm was detected in 4 additional patients, but 1 patient lost the hydrogen-based diagnosis of malabsorption (Cohen kappa = 0.92). CONCLUSIONS: Methane measurement did not significantly affect the detection rate of carbohydrate malabsorbers in children/adolescents with functional abdominal complaints when established cut-offs are used. The use of CO2 correction altered the diagnosis of malabsorption in a minority of patients but did not significantly alter overall test results.

Carbohydrate-induced gastrointestinal symptoms: development and validation of a test-specific symptom questionnaire for an adult population, the adult Carbohydrate Perception Questionnaire.

OBJECTIVES: Carbohydrate intolerances may affect a majority of the worlds-population but there is no validated, test-specific assessment of carbohydrate-induced symptoms during breath tests. We aimed to develop and validate a questionnaire for evaluation and quantification of carbohydrate intolerance. METHODS: A visual analog scale-questionnaire with five complaints (pain, nausea, bloating, flatulence, and diarrhea) was designed. The time frame of symptoms was 'current' (for baseline symptoms) and 'since filling out the last questionnaire'. Validity was determined in focus-group style interviews and during breath tests in an original (n = 342) and follow-up patient groups (n = 338). RESULTS: The questionnaire had good face validity, content validity ratio according to Lawshe was 1. Intraclass correlation coefficients (n = 195; 30-min' interval) demonstrated excellent reliability (P < 0.001), Cohen's d (measure of effect size) was small (≤0.19 for each symptom). Convergent and discriminant validity were supported against patient interviews. Questionnaire-derived results highly correlated with a medical interview (P < 0.001; n = 338). Responsiveness to change was verified during breath tests despite small effect sizes (≤0.32). Additional cross-validation and external validation studies (follow-up in-house: n = 182; external: n = 156) demonstrated generalizability and identified relevant numbers of patients in whom there was no co-occurrence of carbohydrate malabsorption and intolerance. CONCLUSIONS: The adult Carbohydrate Perception Questionnaire is a valid instrument for the assessment of gastrointestinal symptoms after carbohydrate ingestion with excellent psychometric properties. It allows standardized, test-specific diagnosis of carbohydrate intolerance and evaluation of the relation between malabsorption and intolerance. It shall be useful for future studies on treatment of carbohydrate intolerance.

Development and validation of the paediatric Carbohydrate Perception Questionnaire (pCPQ), an instrument for the assessment of carbohydrate-induced gastrointestinal symptoms in the paediatric population.

BACKGROUND: There is an unmet need for a validated, test-specific symptom questionnaire to evaluate carbohydrate perception during breath tests. Our aim was to develop and validate a questionnaire for the assessment of symptoms after a provocative carbohydrate load. METHODS: After a literature search and initial focus group-style interviews, five relevant complaints were identified. Responses were given on a Likert-type faces scale with a language children use and understand. Reliability, validity and responsiveness to change were established by the implementation of the questionnaire during breath tests in 215 pediatric subjects. Correlation between the questionnaire and a medical interview by a pediatrician who was blinded to the results of the questionnaire (n = 19) was determined. KEY RESULTS: The questionnaire had good face and content validity (Lawshe ratio = 1). Intraclass correlation coefficients for test-retest reliability (n = 116) demonstrated good repeatability (P < .001), and effect sizes were small (Cohen's d < 0.15 for all symptoms). Convergent validity and discriminant validity were supported according to the multitrait-multimethod matrix method. The results obtained by the questionnaire correlated highly with the result of the medical interview (P < .001; Fisher's exact test). Cronbach's alpha was 0.81. Responsiveness was verified for the whole patient group and subgroups with medium to high effect sizes. CONCLUSIONS AND INFERENCES: The paediatric Carbohydrate Perception Questionnaire (pCPQ) is a simple, test-specific questionnaire for a pediatric population. It is a valid instrument with excellent psychometric properties to assess gastrointestinal symptoms after carbohydrate ingestion. The pCPQ can replace non-validated symptom assessment during carbohydrate breath tests and allows a standardized diagnosis of carbohydrate intolerance.

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] [...].

Gastric administration of garlic powder containing the trpa1- agonist allicin induces specific epigastric symptoms and gastric relaxation in healthy subjects.

BACKGROUND: TRPA1 is an excitatory ion channel and is involved in sensory processes including thermal nociception and inflammatory pain. The allicin in garlic is a strong activator of the TRPA1 channel. AIM: To evaluate the effect of intragastric garlic powder containing allicin on perception, gastric tone, and mechanosensitivity. METHODS: An infusion-barostat balloon assembly was used for infusion of test solutions, for distension, and to measure proximal gastric compliance and tone. After an initial open label dose finding with 1 g, 2 g, 3.75 g, and 7.5 g commercially available garlic powder, a bolus of 2 g garlic powder (11 mg allicin)/60 mL H2 O was considered to induce moderate but constant sensation and was used hereafter in a placebo-controlled, single-dose, double-blind, randomized study in 7 volunteers to evaluate gastric sensation, tone, and mechanosensitivity. KEY RESULTS: Bolus injection of garlic caused immediate epigastric symptoms, mean aggregate symptom scores (AUC in 15 minutes) were 106 ± 49 vs. 35 ± 30 after placebo (P = 0.01). Garlic induced significant epigastric pressure, stinging, and warmth (P < 0.01 vs. placebo), while intensity of cramps, satiety, nausea, and pain was not significantly different to placebo (P > 0.05). Garlic induced an immediate, short lived fundic relaxation (balloon volume 627 ± 349 mL vs. -145 ± 120 mL; P < 0.02). No effect of allicin on proximal gastric mechanosensitivity and compliance was observed (NS). CONCLUSION AND INFERENCES: Garlic containing allicin induces immediate epigastric symptoms of pressure, stinging, and warmth and induces fundic relaxation but does not influence mechanosensitivity or compliance. TRPA1 is a receptor that is involved in gastric sensation and motility.

Overlap of Irritable Bowel Syndrome and Functional Dyspepsia in the Clinical Setting: Prevalence and Risk Factors.

BACKGROUND: According to Rome IV criteria, functional dyspepsia (FD) and irritable bowel syndrome (IBS) are distinct functional gastrointestinal disorders (FGID); however, overlap of these conditions is common in population-based studies, but clinical data are lacking. AIMS: To determine the overlap of FD and IBS in the clinical setting and define risk factors for the overlap of FD/IBS. METHODS: A total of 1127 consecutive gastroenterology outpatients of a tertiary center were recruited and symptoms assessed with a standardized validated questionnaire. Patients without evidence for structural or biochemical abnormalities as a cause of symptoms were then categorized based upon the symptom pattern as having FD, IBS or FD/IBS overlap. Additionally, this categorization was compared with the clinical diagnosis documented in the integrated electronic medical records system. RESULTS: A total of 120 patients had a clinical diagnosis of a FGID. Based upon standardized assessment with a questionnaire, 64% of patients had FD/IBS overlap as compared to 23% based upon the routine clinical documentation. In patients with severe IBS or FD symptoms (defined as symptoms affecting quality of life), the likelihood of FD/IBS overlap was substantially increased (OR = 3.1; 95%CI 1.9-5.0) and (OR = 9.0; 95%CI 3.5-22.7), respectively. Thus, symptom severity for IBS- or FD symptoms were significantly higher for patients with FD/IBS overlap as compared to patients with FD or IBS alone (p all < 0.01). Age, gender and IBS-subtype were not associated with overlap. CONCLUSION: In the clinical setting, overlap of FD and IBS is the norm rather than the exception. FD/IBS overlap is associated with a more severe manifestation of a FGID.

Correction to: Relationship Between Abdominal Symptoms and Fructose Ingestion in Children with Chronic Abdominal Pain.

The original version of this article unfortunately contained an error in a couple of reference citation in Discussion Section, paragraph 6. The reference citation number should be changed from [6] to [9] in the below sentences so that it reads.

Identification of Individuals with Functional Dyspepsia With a Simple, Minimally Invasive Test: A Single Center Cohort Study of the Oral Capsaicin Test.

OBJECTIVES: The diagnosis of functional dyspepsia (FD) is challenging due to the lack of reliable biological markers to support the diagnosis. We assessed the relevance of a previously validated simple test for chemical hypersensitivity in the setting of a gastrointestinal outpatient department. METHODS: A total of 224 outpatients who were referred for evaluation of gastrointestinal symptoms in the absence of alarm symptoms swallowed a capsule containing 0.75 mg capsaicin. Severity of symptoms before and after capsule ingestion was assessed by a graded questionnaire and the difference in aggregate symptom scores (delta) was calculated. RESULTS: Sensitivity of the test was between 0.51-0.59, specificity was 0.84-0.89 and positive predictive value for the diagnosis of FD 70-71%. FD patients had significantly higher median delta symptom scores (10.0; 25% quartile: 3.0; 75% quartile: 16.0) as compared to inflammatory bowel disease (2.5; 1.0/8.5)(P=0.003), peptic ulcer disease (0.0; -1.5/4.5) (P<0.001), irritable bowel syndrome (3.0;0.5/8.5)(P=0.001), and patients classified with "other disease" (2.5;0.0/5.0)(P<0.001). Patients with gastroesophageal reflux disease had significantly lower symptom scores if FD was not concomitantly diagnosed (2.0; 0.0/6.0) than if FD was present (10.0; 4.0/15.0). CONCLUSIONS: Hypersensitivity for capsaicin discriminates functional dyspepsia from patients with other GI disorders. The capsaicin test is a simple and non invasive method to detect a large subgroup of functional dyspepsia with chemical hypersensitivity. These findings might open new diagnostic options in functional dyspepsia and possibly new therapeutic options by targeting the specific capsaicin receptor TRPV1.

Relationship Between Abdominal Symptoms and Fructose Ingestion in Children with Chronic Abdominal Pain.

BACKGROUND: Limited valid data are available regarding the association of fructose-induced symptoms, fructose malabsorption, and clinical symptoms. AIM: To develop a questionnaire for valid symptom assessment before and during a carbohydrate breath test and to correlate symptoms with fructose breath test results in children/adolescents with functional abdominal pain. METHODS: A Likert-type questionnaire assessing symptoms considered relevant for hydrogen breath test in children was developed and underwent initial validation. Fructose malabsorption was determined by increased breath hydrogen in 82 pediatric patients with functional abdominal pain disorders; fructose-induced symptoms were quantified by symptom score ≥2 and relevant symptom increase over baseline. The results were correlated with clinical symptoms. The time course of symptoms during the breath test was assessed. RESULTS: The questionnaire exhibited good psychometric properties in a standardized assessment of the severity of carbohydrate-related symptoms. A total of 40 % (n = 33) had malabsorption; symptoms were induced in 38 % (n = 31), but only 46 % (n = 15) with malabsorption were symptomatic. There was no significant correlation between fructose malabsorption and fructose-induced symptoms. Clinical symptoms correlated with symptoms evoked during the breath test (p < 0.001, r2 = 0.21) but not with malabsorption (NS). Malabsorbers did not differ from non-malabsorbers in terms of symptoms during breath test. Symptomatic patients had significantly higher pain and flatulence scores over the 9-h observation period (p < 0.01) than did nonsymptomatic patients; the meteorism score was higher after 90 min. CONCLUSIONS: Fructose-induced symptoms but not fructose malabsorption are related to increased abdominal symptoms and have distinct timing patterns.

Lack of an Effect of Gastric Capsaicin on the Rectal Component of the Gastrocolonic Response.

Luminal capsaicin induces local and distant reflexes in the upper gastrointestinal tract and stimulates lower gastrointestinal symptoms in susceptible persons. We aimed to evaluate the effect of gastric capsaicin on rectal motor function and sensation. METHODS: Eighteen healthy volunteers participated twice, at least 1 week apart, in this double-blind, placebo-controlled crossover study. Participants swallowed a gastric tube for capsaicin or saline infusion. A barostat tube was placed in the rectum to measure rectal tone before and during gastric capsaicin (40 µg/ml, 2.5 ml/min) or placebo infusion and to conduct distension experiments before and after gastric infusions. Gastric infusions were terminated after 60 min or when epigastric discomfort occurred. Differences in rectal tone, compliance, and sensitivity between gastric placebo and gastric capsaicin were determined. RESULTS: On both study days, basal rectal volumes, compliance, and sensitivity parameters were comparable (NS) before gastric infusions. Gastric capsaicin infusion induced epigastric discomfort that necessitated termination of infusion after 29.6 ± 12.3 min (saline: 54.7 ± 8.9 min; p < 0.01). Rectal tone, aggregate perception scores, and rectal compliance did not differ between placebo and capsaicin trials (p > 0.05). Rectal tone increased significantly only when capsaicin induced epigastric discomfort (p < 0.05). The reproducibility of the barostat trial was acceptable with significant correlations of volumes, pressures (< 0.05; r 2 from 0.41 to 0.55), rectal compliance (p < 0.01; r 2 = 0.44), and aggregate perception scores (p values all < 0.05; r 2 from 0.44 to 0.0.65) between the two barostat trials. CONCLUSION: Gastric perfusion with capsaicin does not directly influence rectal physiology through a reflex arc.

Diarrhea caused by carbohydrate malabsorption.

This article will focus on the role of the colon in the pathogenesis of diarrhea in carbohydrate malabsorption or physiologically incomplete absorption of carbohydrates, and on the most common manifestation of carbohydrate malabsorption, lactose malabsorption. In addition, incomplete fructose absorption, the role of carbohydrate malabsorption in other malabsorptive diseases, and congenital defects that lead to malabsorption will be covered. The article concludes with a section on diagnostic tools to evaluate carbohydrate malabsorption.