RESUMO
BACKGROUND AND AIMS: Archaea constitute one of the main three domains of the tree of life, distinct from eukaryotes and bacteria. Excessive luminal loads of methanogenic archaea (intestinal methanogen overgrowth, IMO) have been implicated in the pathophysiology of various diseases, including constipation. To elucidate the phenotypical presentation of IMO, we performed a systematic review and meta-analysis of the prevalence and severity of gastrointestinal (GI) symptoms in subjects with IMO as compared to subjects without IMO. METHODS: Electronic databases, including OVID MEDLINE and Cochrane Database from inception until September 2023, were systematically searched. Prevalence rates, odds ratios (ORs), standardized mean difference (SMD) and 95% confidence intervals (CIs) of symptoms were calculated. RESULTS: Nineteen studies were included (1293 patients with IMO and 3208 controls). IMO patients exhibited various GI symptoms, including bloating (78%), constipation (51%), diarrhea (33%), abdominal pain (65%), nausea (30%), and flatulence (56%). Patients with IMO had a significantly higher prevalence of constipation as compared to controls (47% vs. 38%, OR 2.04, 95% CI 1.48-2.83, p<0.0001) along with lower prevalence of diarrhea (37% vs. 52%, OR 0.58, 95% CI 0.37-0.90, p=0.01) and nausea (32% vs. 45%, OR 0.75, 95% CI 0.60-0.94, p=0.01). Patients with IMO had higher severity of constipation (SMD 0.77; 95% CI 0.11-1.43, p=0.02) and lower severity of diarrhea (SMD -0.71, 95% CI -1.39, -0.03, p=0.04). Significant heterogeneity was detected. CONCLUSION: Patients with IMO exhibit a higher rate and severity of constipation along with lower rate and severity of diarrhea. The distinct phenotype of IMO patients should be incorporated in patient-reported outcome measures and further correlated with mechanistic microbiome studies.
RESUMO
BACKGROUND& AIMS: Despite accelerated research in small intestinal bacterial overgrowth (SIBO), questions remain regarding optimal diagnostic approaches and definitions. Here, we aim to define SIBO using small bowel culture and sequencing, identifying specific contributory microbes, in the context of gastrointestinal symptoms. METHODS: Subjects undergoing esophagogastroduodenoscopy (without colonoscopy) were recruited and completed symptom severity questionnaires. Duodenal aspirates were plated on MacConkey and blood agar. Aspirate DNA was analyzed by 16S ribosomal RNA and shotgun sequencing. Microbial network connectivity for different SIBO thresholds and predicted microbial metabolic functions were also assessed. RESULTS: A total of 385 subjects with <103 colony forming units (CFU)/mL on MacConkey agar and 98 subjects with ≥103 CFU/mL, including ≥103 to <105 CFU/mL (N = 66) and ≥105 CFU/mL (N = 32), were identified. Duodenal microbial α-diversity progressively decreased, and relative abundance of Escherichia/Shigella and Klebsiella increased, in subjects with ≥103 to <105 CFU/mL and ≥105 CFU/mL. Microbial network connectivity also progressively decreased in these subjects, driven by the increased relative abundance of Escherichia (P < .0001) and Klebsiella (P = .0018). Microbial metabolic pathways for carbohydrate fermentation, hydrogen production, and hydrogen sulfide production were enhanced in subjects with ≥103 CFU/mL and correlated with symptoms. Shotgun sequencing (N = 38) identified 2 main Escherichia coli strains and 2 Klebsiella species representing 40.24% of all duodenal bacteria in subjects with ≥103 CFU/mL. CONCLUSIONS: Our findings confirm ≥103 CFU/mL is the optimal SIBO threshold, associated with gastrointestinal symptoms, significantly decreased microbial diversity, and network disruption. Microbial hydrogen- and hydrogen sulfide-related pathways were enhanced in SIBO subjects, supporting past studies. Remarkably few specific E coli and Klebsiella strains/species appear to dominate the microbiome in SIBO, and correlate with abdominal pain, diarrhea, and bloating severities.
Assuntos
Gastroenteropatias , Sulfeto de Hidrogênio , Humanos , Ágar , Escherichia coli , Sequenciamento de Nucleotídeos em Larga Escala , Hidrogênio , Testes RespiratóriosRESUMO
INTRODUCTION: Gut microbiome changes are linked to obesity, but findings are based on stool data. In this article, we analyzed the duodenal microbiome and serum biomarkers in subjects with normal weight, overweight, and obesity. METHODS: Duodenal aspirates and serum samples were obtained from subjects undergoing standard-of-care esophagogastroduodenoscopy without colon preparation. Aspirate DNAs were analyzed by 16S rRNA and shotgun sequencing. Predicted microbial metabolic functions and serum levels of metabolic and inflammatory biomarkers were also assessed. RESULTS: Subjects with normal weight (N = 105), overweight (N = 67), and obesity (N = 42) were identified. Overweight-specific duodenal microbial features include lower relative abundance (RA) of Bifidobacterium species and Escherichia coli strain K-12 and higher Lactobacillus intestinalis , L. johnsonii , and Prevotella loescheii RA. Obesity-specific features include higher Lactobacillus gasseri RA and lower L. reuteri (subspecies rodentium ), Alloprevotella rava , and Leptotrichia spp RA. Escalation features (progressive changes from normal weight through obesity) include decreasing Bacteroides pyogenes , Staphylococcus hominis , and unknown Faecalibacterium species RA, increasing RA of unknown Lactobacillus and Mycobacterium species, and decreasing microbial potential for biogenic amines metabolism. De-escalation features (direction of change altered in normal to overweight and overweight to obesity) include Lactobacillus acidophilus , L. hominis , L. iners , and Bifidobacterium dentium . An unknown Lactobacillus species is associated with type IIa dyslipidemia and overweight, whereas Alloprevotella rava is associated with type IIb and IV dyslipidemias. DISCUSSION: Direct analysis of the duodenal microbiome has identified key genera associated with overweight and obesity, including some previously identified in stool, e.g., Bifidobacterium and Lactobacillus . Specific species and strains exhibit differing associations with overweight and obesity, including escalation and de-escalation features that may represent targets for future study and therapeutics.
Assuntos
Microbioma Gastrointestinal , Obesidade , Sobrepeso , Humanos , Obesidade/microbiologia , Feminino , Masculino , Sobrepeso/microbiologia , Pessoa de Meia-Idade , Adulto , Duodeno/microbiologia , RNA Ribossômico 16S/genética , Biomarcadores/sangue , Lactobacillus/isolamento & purificação , Bifidobacterium/isolamento & purificação , IdosoRESUMO
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.
RESUMO
The z-line refers to the squamocolumnar junction which marks the transition between the normal stratified squamous epithelium of the distal esophagus and the columnar epithelium of the gastric cardia. An "irregular" z-line refers to an irregular appearing squamocolumnar junction characterized by the presence of columnar mucosa less than 1 cm in length that extends above the gastroesophageal junction. In contrast, Barrett's esophagus is diagnosed when columnar mucosa of at least 1 cm is seen in the distal esophagus extending above the gastroesophageal junction with biopsies demonstrating specialized intestinal metaplasia. Current guidelines recommend against taking routine biopsies from a normal or irregular z-line in the absence of visible abnormalities and advise against endoscopic surveillance in this patient population, in large part due to multiple studies demonstrating lack of progression to advanced neoplasia such as high-grade dysplasia or esophageal adenocarcinoma in patients with an irregular z-line. Despite these recommendations, a sizable number of patients without Barrett's esophagus undergo biopsies from the z-line and are subsequently recommended to have surveillance endoscopies. Furthermore, patients with an irregular z-line are often mislabelled as Barrett's esophagus resulting in significant downstream consequences including higher healthcare costs and reduced health-related quality of life. In this review, we highlight the importance of landmark identification of the distal esophagus and gastroesophageal junction at the time of endoscopy, share recommendations from current guidelines related to the z-line, examine rates of neoplastic progression in those with an irregular z-line, discuss consequences of routinely biopsying an irregular z-line, and highlight strategies on how to approach an irregular z-line if seen on endoscopy. A careful, high-quality endoscopic examination can help to identify visible abnormalities at the z-line, which, if present, should be targeted for biopsies to rule out dysplasia and neoplasia.
Assuntos
Esôfago de Barrett , Neoplasias Esofágicas , Humanos , Esôfago de Barrett/patologia , Esôfago de Barrett/diagnóstico , Biópsia/métodos , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/diagnóstico , Junção Esofagogástrica/patologia , Esôfago/patologia , Adenocarcinoma/patologia , Adenocarcinoma/diagnóstico , Cárdia/patologia , Esofagoscopia/métodosRESUMO
Elemental diets have been employed for the management of various diseases for over 50 years, with several mechanisms mediating their beneficial effects. Yet, they are underutilized due to poor palatability, access, cost, and lack of awareness regarding their clinical efficacy. Therefore, in this review, we aimed to systematically search and review the literature to summarize the formulation variability, mechanisms of action, clinical applications, and tolerability of the elemental diets in gastrointestinal diseases. While large prospective trials are lacking, elemental diets appear to exhibit objective and subjective clinical benefit in several diseases, including eosinophilic esophagitis, eosinophilic gastroenteritis, inflammatory bowel diseases, small intestinal bacterial overgrowth, intestinal methanogen overgrowth, chemoradiotherapy-associated mucositis, and celiac disease. Although some data support the long-term use of elemental diets as an add-on supplement for chronic pancreatitis and Crohn's disease, most of the literature on exclusive elemental diets focuses on inducing remission. Therefore, subsequent treatment strategies for maintaining remission need to be adopted in chronic/relapsing diseases. Several mechanistic pathways were identified to mediate the effects of elemental diets, including food additive and allergen-free content, high passive absorption rate, and anti-inflammatory properties. High rates of intolerance up to 40% are seen in the trials where exclusive elemental diets were administered orally due to poor organoleptic acceptability; however, when tolerated, adverse events were rare. Other limitations of elemental diets are cost, access, and lifestyle/social restrictions. Moreover, judicious use is advised in presence of a concomitant restrictive food intake disorders. Elemental diets offer a potentially highly efficacious dietary intervention with minor side effects. Palatability, cost, access, and social restrictions are common barriers of use. Prospective clinical trials are needed to elucidate the role of elemental formulas in the management of individual diseases.
RESUMO
BACKGROUND: We recently demonstrated that diarrhea-predominant irritable bowel syndrome (IBS-D) subjects have higher relative abundance (RA) of hydrogen sulfide (H2S)-producing Fusobacterium and Desulfovibrio species, and constipation-predominant IBS (IBS-C) subjects have higher RA of methanogen Methanobrevibacter smithii. AIMS: In this study, we investigate the effects of increased methanogens or H2S producers on stool phenotypes in rat models. METHODS: Adult Sprague-Dawley rats were fed high-fat diet (HFD) for 60 days to increase M. smithii levels, then gavaged for 10 days with water (controls) or methanogenesis inhibitors. To increase H2S producers, rats were gavaged with F. varium or D. piger. Stool consistency (stool wet weight (SWW)) and gas production were measured. 16S rRNA gene sequencing was performed on stool samples. RESULTS: In HFD diet-fed rats (N = 30), stool M. smithii levels were increased (P < 0.001) after 52 days, correlating with significantly decreased SWW (P < 0.0001) at 59 days (R = - 0.38, P = 0.037). Small bowel M. smithii levels decreased significantly in lovastatin lactone-treated rats (P < 0.0006), and SWW increased (normalized) in lovastatin hydroxyacid-treated rats (P = 0.0246), vs. controls (N = 10/group). SWW increased significantly in D. piger-gavaged rats (N = 16) on day 10 (P < 0.0001), and in F. varium-gavaged rats (N = 16) at all timepoints, vs. controls, with increased stool H2S production. 16S sequencing revealed stool microbiota alterations in rats gavaged with H2S producers, with higher relative abundance (RA) of other H2S producers, particularly Lachnospiraceae and Bilophila in F. varium-gavaged rats, and Sutterella in D. piger-gavaged rats. CONCLUSIONS: These findings suggest that increased M. smithii levels result in a constipation-like phenotype in a rat model that is partly reversible with methanogenesis inhibitors, whereas gavage with H2S producers D. piger or F. varium results in increased colonization with other H2S producers and diarrhea-like phenotypes. This supports roles for the increased RA of methanogens and H2S producers identified in IBS-C and IBS-D subjects, respectively, in contributing to stool phenotypes.
Assuntos
Sulfeto de Hidrogênio , Síndrome do Intestino Irritável , Humanos , Adulto , Ratos , Animais , Síndrome do Intestino Irritável/microbiologia , Metano , RNA Ribossômico 16S/genética , Ratos Sprague-Dawley , Constipação Intestinal/etiologia , Constipação Intestinal/microbiologia , Diarreia/microbiologia , Modelos Animais , LovastatinaRESUMO
High-resolution esophageal manometry (HREM) is a fundamental diagnostic tool in esophagology. Educational tools for this procedure have remained scarce. This quality improvement project aimed to develop an enhanced digital recording about HREM and assess the effect on patient knowledge, anxiety, satisfaction, and procedure abortion rates. The Institute for Healthcare Improvement Model for Improvement and the self-regulation theory guided this project. An interprofessional team was formed. A video recording of the pre-, peri-, and post-HREM care was created. Participants were recruited in the following four cycles: Baseline, Workstation, Manometry, and Home. Questionnaires were collected pre- and postvideo education. The results demonstrated a significant increase in knowledge from 60% to 96% ( p < .001), 58% to 96% ( p < .001), 79% to 96% ( p < .001), and 92% to 97% ( p = .02) and reductions in anxiety from 7.1 to 5.5 ( p = .003), 7.6 to 6.1 ( p = .003), 7.1 to 6.5 ( p < .001), and 6.4 to 6.1 ( p = .03) in all four groups. Almost all (99.5%) participants liked the recorded education and only 2.6% of cases were aborted during the 1-year project implementation period from June 2020 to May 2021. Findings from this project support the positive impact of recorded patient education. An educational recording is standardized and has the potential to be implemented in variable settings.
Assuntos
Ansiedade , Esôfago , Humanos , Manometria/métodos , Ansiedade/diagnóstico , Ansiedade/prevenção & controle , Transtornos de Ansiedade , EmoçõesRESUMO
Gastroparesis is a functional gastrointestinal disorder that more commonly affects women, with most cases being diagnosed during childbearing age. However, there is a paucity of data and guidelines to specifically highlight the epidemiology, disease course, maternal and fetal impact, and the management of existing gastroparesis during pregnancy. Apart from metoclopramide, there is no approved therapy specifically indicated for gastroparesis. More importantly, pregnant and breastfeeding women are excluded from clinical trials evaluating pharmacologic agents in the management of gastroparesis. This poses a real challenge to healthcare providers in counseling and managing patients with gastroparesis. In this systematic review, we summarize the current available literature and the knowledge gaps in the impact of pregnancy on gastroparesis and vice versa. We also highlight the efficacy and safety profiles of available pharmacologic and nonpharmacologic therapies in the management of patients with gastroparesis, with emphasis on judicious use of dietary approaches that are deemed relatively safe during pregnancy.
Assuntos
Gastroparesia , Gravidez , Humanos , Feminino , Gastroparesia/tratamento farmacológico , Fármacos Gastrointestinais/efeitos adversos , Metoclopramida/uso terapêuticoRESUMO
BACKGROUND: Despite achieving remission in inflammatory bowel disease (IBD), persistent gastrointestinal symptoms are common in quiescent IBD. While irritable bowel syndrome (IBS) is commonly diagnosed in IBD, IBS-like symptoms of recurrent abdominal pain and altered bowel habits can also be attributed to a wide range of overlapping gastrointestinal (GI) etiologies and systemic disorders with GI manifestations that often do not respond to conventional IBS therapies. Delay in diagnosis of these conditions can lead to ongoing patient suffering, reduced quality of life, repetition of invasive testing, increased healthcare utilization, and potentially unnecessary empirical escalation of IBD-related treatments. AIMS: This review provides a practical approach for the evaluation and diagnosis of IBS mimickers in IBD. We summarize the definition, pathophysiology, diagnosis and treatment of the potential etiologies causing unexplained GI symptoms. CONCLUSION: Overlapping conditions can co-exist with IBD and explain IBS-like symptoms. The diagnostic work-up in this population should be individualized and tailored to the predominant symptom pattern, associated clinical signs and symptoms and predisposing conditions that can be obtained from a detailed history and physical examination.
RESUMO
OBJECTIVES: Colorectal cancer (CRC) is the third most common malignancy in the US. Several factors are associated with increased/decreased CRC risk and often linked to adenomatous colorectal polyps (CRP). Recent studies suggest a lower risk of neoplastic lesions among irritable bowel syndrome (IBS) patients. We aimed to systematically assess the occurrence of CRC and CRP in IBS patients. METHODS: Searches of the Medline, Cochrane, and EMBASE databases were performed, blindly and independently, by two investigators. Studies of CRC or CRP incidence in IBS patients (diagnosed by Rome or other symptom-based criteria) were eligible for inclusion. CRC and CRP effect estimates were pooled in meta-analyses using random models. RESULTS: Of 4941 non-duplicate studies, 14 were included, comprising 654,764 IBS patients and 2,277,195 controls in 8 cohort studies, and 26,641 IBS patients and 87,803 controls in 6 cross-sectional studies. Pooled analysis revealed a significantly decreased prevalence of CRP in IBS subjects vs. controls, with a pooled odds ratio (OR) of 0.29 (95% CI (0.15, 0.54)). There was significant heterogeneity between studies (I2 = 96%, p < 0.01). This finding persisted when studies which did not report pre-cancerous polyps separately were excluded (OR 0.23, 95% CI (0.15, 0.35), I2 = 85%, p < 0.01). CRC prevalence was lower in IBS subjects, but this did not reach statistical significance (OR 0.40, 95% CI (0.09, 1.77]). CONCLUSION: Our analyses reveal a decreased incidence of colorectal polyps in IBS, although CRC did not reach significance. Mechanistic studies with detailed genotypic analysis and clinical phenotyping are needed to better elucidate the potentially protective effect of IBS on CRC development.
Assuntos
Pólipos do Colo , Neoplasias Colorretais , Síndrome do Intestino Irritável , Pólipos do Colo/epidemiologia , Síndrome do Intestino Irritável/epidemiologia , Neoplasias Colorretais/epidemiologia , Incidência , HumanosRESUMO
BACKGROUND: Interleukin (IL)-10 knockout (KO) mice, a model for inflammatory bowel disease (IBD), develop chronic enterocolitis due to an aberrant immune response to enteric antigens. Endoscopy, the gold standard for evaluation of human mucosal health, is not widely available for murine models. AIMS: To assess the natural history of left-sided colitis in IL-10 KO mice via serial endoscopies. METHODS: BALB/cJ IL-10 KO mice underwent regular endoscopic assessments from 2 up to 8 months of age. Procedures were recorded and blindly evaluated using a 4-component endoscopic score: mucosal wall transparency, intestinal bleeding, focal lesions and perianal lesions (0-3 points each). An endoscopic score ≥ 1 point was considered as the presence of colitis/flare. RESULTS: IL-10 KO mice (N = 40, 9 female) were assessed. Mean age at first endoscopy was 62.5 ± 2.5 days; average number of procedures per mouse was 6.0 ± 1.3. A total of 238 endoscopies were conducted every 24.8 ± 8.3 days, corresponding to 124.1 ± 45.2 days of surveillance per mouse. Thirty-three endoscopies in 24 mice (60%) detected colitis, mean endoscopy score 2.5 ± 1.3 (range: 1-6.3). Nineteen mice (47.5%) had one episode of colitis and 5 (12.5%) had 2-3 episodes. All exhibited complete spontaneous healing on subsequent endoscopies. CONCLUSIONS: In this large-scale endoscopic surveillance study of IL-10 KO mice, 40% of mice did not develop endoscopic left-sided colitis. Furthermore, IL-10 KO mice did not exhibit persistent colitis and universally exhibited complete spontaneous healing without treatment. The natural history of colitis in IL-10 KO mice may not be comparable with that of IBD in humans and requires careful consideration.
Assuntos
Colite , Doenças Inflamatórias Intestinais , Interleucina-10 , Animais , Feminino , Camundongos , Colite/genética , Colite/patologia , Modelos Animais de Doenças , Endoscopia , Inflamação , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Interleucina-10/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , MasculinoRESUMO
PURPOSE: The aim of this study was to generate evidence supporting the development and content validity of a new PRO instrument, the Small Intestinal Bacterial Overgrowth (SIBO) Symptom Measure (SSM) daily diary. The SSM assesses symptom severity in SIBO patients, with the ultimate goal of providing a fit for purpose PRO for endpoint measurement. METHODS: Qualitative research included 35 SIBO patients in three study stages, using a hybrid concept elicitation (CE)/cognitive interview (CI) method with US patients, ≥ 18 years. Stage 1 included a literature review, clinician interviews, and initial CE interviews with SIBO patients to identify symptoms important to patients for inclusion in the SSM. Stage 2 included hybrid CE/CI to learn more about patients' SIBO experience and test the draft SSM. Finally, stage 3 used CIs to refine the instrument and test its content validity. RESULTS: In stage 1 (n = 8), 15 relevant concepts were identified, with items drafted based on the literature review/clinician interviews and elicitation work. Within stage 2 (n = 15), the SSM was refined to include 11 items; with wording revised for three items. Stage 3 (n = 12) confirmed the comprehensiveness of the SSM, as well as appropriateness of the item wording, recall period, and response scale. The resulting 11-item SSM assesses the severity of bloating, abdominal distention, abdominal discomfort, abdominal pain, flatulence, physical tiredness, nausea, diarrhea, constipation, appetite loss, and belching. CONCLUSIONS: This study provides evidence supporting the content validity of the new PRO. Comprehensive patient input ensures that the SSM is a well-defined measure of SIBO, ready for psychometric validation studies.
Assuntos
Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Humanos , Qualidade de Vida/psicologia , Pesquisa Qualitativa , Psicometria , Exame FísicoRESUMO
INTRODUCTION: Although gut-directed psychotherapies are effective for irritable bowel syndrome (IBS), they are rarely prescribed, given a paucity of trained clinicians. Virtual reality (VR) offers a solution by allowing patients to self-practice these techniques in a standardized manner. METHODS: A multidisciplinary team developed IBS/VR, a program that transports users into immersive VR worlds that teach patients about the brain-gut axis, cognitive behavioral therapy, and gut-directed meditation. We tested IBS/VR in Rome IV IBS patients and used inductive analysis to evaluate perceptions and identify recommendations. RESULTS: We achieved thematic saturation after 9 interviews; 3 additional interviews revealed no emergent themes. After making 23 software changes based on patient feedback, we conducted 3 additional interviews which confirmed thematic saturation (N = 15 total). DISCUSSION: This study offers initial validation of the first VR program designed for IBS.
Assuntos
Terapia Cognitivo-Comportamental , Síndrome do Intestino Irritável , Meditação , Realidade Virtual , Terapia Cognitivo-Comportamental/métodos , Humanos , Síndrome do Intestino Irritável/psicologia , Síndrome do Intestino Irritável/terapiaRESUMO
INTRODUCTION: A 2-hour breath test is the gold standard for diagnosing intestinal methanogen overgrowth (IMO). This method can be cumbersome especially if used repetitively to monitor treatment response. Therefore, we aimed to assess the reliability of a fasting single methane measurement (SMM) in diagnosing IMO and its utility as a biomarker to monitor treatment response in subjects with IMO. METHODS: First, we calculated the test characteristics of SMM compared with lactulose and glucose breath test in 2 large-scale retrospective cohorts. Second, the symptomology associated with SMM using various cutoffs was analyzed. Third, in a double-blind randomized control trial, the temporal stability of SMM levels in subjects taking placebo was analyzed. Fourth, stool Methanobrevibacter smithii loads were quantified using quantitative polymerase chain reaction and compared with SMM levels. Last, the change in SMM over time during antibiotic therapy was analyzed. RESULTS: Using the cutoff of SMM ≥10 ppm, SMM had a sensitivity of 86.4% and specificity of 100% for diagnosing IMO on the glucose and lactulose breath tests and was associated with constipation (5.65 ± 3.47 vs 4.32 ± 3.62, P = 0.008). SMM remained stable for 14 weeks without treatment (P = 0.45), and antibiotics lead to a decrease in SMM after 2 days (P < 0.0001). SMM was positively associate with stool M. smithii load (R = 0.65, P < 0.0001). DISCUSSION: Fasting SMM ≥10 ppm seems to accurately diagnose IMO, is associated with constipation, and correlates with stool M. smithii. SMM seems to be stable without treatment and decreases after antibiotics. SMM may be a useful test to diagnose IMO and monitor treatment response.
Assuntos
Síndrome do Intestino Irritável , Lactulose , Antibacterianos/uso terapêutico , Testes Respiratórios , Constipação Intestinal/tratamento farmacológico , Jejum , Glucose , Humanos , Síndrome do Intestino Irritável/complicações , Lactulose/uso terapêutico , Metano/análise , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
INTRODUCTION: Stool form assessment relies on subjective patient reports using the Bristol Stool Scale (BSS). In a novel smartphone application (app), trained artificial intelligence (AI) characterizes digital images of users' stool. In this study, we evaluate this AI for accuracy in assessing stool characteristics. METHODS: Subjects with diarrhea-predominant irritable bowel syndrome image-captured every stool for 2 weeks using the app, which assessed images for 5 visual characteristics (BSS, consistency, fragmentation, edge fuzziness, and volume). In the validation phase, using 2 expert gastroenterologists as a gold standard, sensitivity, specificity, accuracy, and diagnostic odds ratios of subject-reported vs AI-graded BSS scores were compared. In the implementation phase, agreements between AI-graded and subject-reported daily average BSS scores were determined, and subject BSS and AI stool characteristics scores were correlated with diarrhea-predominant irritable bowel syndrome symptom severity scores. RESULTS: In the validation phase (n = 14), there was good agreement between the 2 experts and AI characterizations for BSS (intraclass correlation coefficients [ICC] = 0.782-0.852), stool consistency (ICC = 0.873-0.890), edge fuzziness (ICC = 0.836-0.839), fragmentation (ICC = 0.837-0.863), and volume (ICC = 0.725-0.851). AI outperformed subjects' self-reports in categorizing daily average BSS scores as constipation, normal, or diarrhea. In the implementation phase (n = 25), the agreement between AI and self-reported BSS scores was moderate (ICC = 0.61). AI stool characterization also correlated better than subject reports with diarrhea severity scores. DISCUSSION: A novel smartphone application can determine BSS and other visual stool characteristics with high accuracy compared with the 2 expert gastroenterologists. Moreover, trained AI was superior to subject self-reporting of BSS. AI assessments could provide more objective outcome measures for stool characterization in gastroenterology.
Assuntos
Síndrome do Intestino Irritável , Aplicativos Móveis , Inteligência Artificial , Diarreia/diagnóstico , Humanos , Síndrome do Intestino Irritável/diagnóstico , Autorrelato , SmartphoneRESUMO
INTRODUCTION: Irritable bowel syndrome (IBS) includes diarrhea-predominant (IBS-D) and constipation-predominant (IBS-C) subtypes. We combined breath testing and stool microbiome sequencing to identify potential microbial drivers of IBS subtypes. METHODS: IBS-C and IBS-D subjects from 2 randomized controlled trials (NCT03763175 and NCT04557215) were included. Baseline breath carbon dioxide, hydrogen (H 2 ), methane (CH 4 ), and hydrogen sulfide (H 2 S) levels were measured by gas chromatography, and baseline stool microbiome composition was analyzed by 16S rRNA sequencing. Microbial metabolic pathways were analyzed using Kyoto Encyclopedia of Genes and Genomes collection databases. RESULTS: IBS-C subjects had higher breath CH 4 that correlated with higher gut microbial diversity and higher relative abundance (RA) of stool methanogens, predominantly Methanobrevibacter , as well as higher absolute abundance of Methanobrevibacter smithii in stool. IBS-D subjects had higher breath H 2 that correlated with lower microbial diversity and higher breath H 2 S that correlated with higher RA of H 2 S-producing bacteria, including Fusobacterium and Desulfovibrio spp. The predominant H 2 producers were different in these distinct microtypes, with higher RA of Ruminococcaceae and Christensenellaceae in IBS-C/CH 4 + (which correlated with Methanobacteriaceae RA) and higher Enterobacteriaceae RA in IBS-D. Finally, microbial metabolic pathway analysis revealed enrichment of Kyoto Encyclopedia of Genes and Genomes modules associated with methanogenesis and biosynthesis of methanogenesis cofactor F420 in IBS-C/CH 4 + subjects, whereas modules associated with H 2 S production, including sulfate reduction pathways, were enriched in IBS-D. DISCUSSION: Our findings identify distinct gut microtypes linked to breath gas patterns in IBS-C and IBS-D subjects, driven by methanogens such as M. smithii and H 2 S producers such as Fusobacterium and Desulfovibrio spp, respectively.
Assuntos
Microbioma Gastrointestinal , Sulfeto de Hidrogênio , Síndrome do Intestino Irritável , Humanos , Síndrome do Intestino Irritável/complicações , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S , BactériasRESUMO
BACKGROUND: Question prompt lists (QPLs) are structured sets of disease-specific questions intended for patient use, enhancing the patient-physician communication by encouraging patients to ask relevant questions during a consultation. Recently, a preliminary 78 question gastroesophageal reflux disease (GERD) specific QPL was created by 12 esophageal experts through a modified Delphi (RAND/University of California, Los Angeles) technique. Patients' perspectives and opinions on each question, however, had not been accounted for in the preliminary expert' version. AIM: The aim was to modify a preliminary experts' QPL, specific to adults with GERD, following patient perspectives and opinions. METHODS: A preliminary GERD QPL was modified through patient input and opinions. Thirty-eight patients with a clinical diagnosis of GERD followed at Stanford University Esophageal Clinic between January and November 2019 were consented to modify the preliminary 78 question expert QPL version. After receiving the QPL in Qualtrics (Provo, UT) by a direct e-mail invitation, patients independently rated questions on a 5-point Likert scale, where 1="should not be included," 2="unimportant," 3="don't know/depends," 4="important," and 5="essential." Questions were accepted for inclusion in the QPL with an a priori interagreement of 80% ranking in the range of 4 to 5. At the end, patients were encouraged to propose additional questions to incorporate into the QPL by open-endedly asking "Are there questions we didn't ask, that you think we should?" RESULTS: Twenty-three patients with GERD (19 female, median age 64) fully participated and modified the existing QPL (60.5%). Of the 78 questions from the preliminary GERD QPL, 66 questions (84.6%) were accepted for inclusion. The question with the highest agreement among patients rating a question as essential consisted of "what habits, food, and drinks do I have to avoid?" (82.6%). Questions eliminated because of disagreement included "What is the natural history of GERD," "Do I have a high chance to die from my Barrett's?," and "Why are you prescribing an antidepressant to treat my GERD?" Nine patients suggested additional questions totaling to 16 separate questions, including "What type of surgeries are there to help GERD?," "What stage is my GERD?," "What are the odds/percentage of getting cancer from GERD?" Incorporating the suggested questions, the final GERD QPL-created by esophageal experts and modified by patients-consisted of 82 questions. CONCLUSION: Esophageal experts and GERD patients have a high level of agreement on important questions, though there is some variation in perspective. Future studies can simplify this list and measure the impact of a shared GERD QPL on patients' decisional conflict and perceived involvement in care.
Assuntos
Refluxo Gastroesofágico , Participação do Paciente , Adulto , Comunicação , Feminino , Refluxo Gastroesofágico/diagnóstico , Humanos , Pessoa de Meia-Idade , Relações Médico-Paciente , Inquéritos e QuestionáriosRESUMO
BACKGROUND: In humans, methane (CH4) is exclusively produced by the intestinal microbiota and has been implicated in several conditions including cardiovascular disease. After microbial production of CH4 in the gut, it steadily crosses into the systemic circulation and reaches the lungs where it can be detected in the exhaled breath, as a surrogate measure for intestinal CH4 production. Recent reports have shown an association between CH4 and vagal dysfunction as well as the inhibition of CH4 activity on ileal contractions with atropine, suggesting its action on the parasympathetic nervous system. Given these findings, we hypothesized that CH4 may be affecting resting heart rate (HR) based on the potential effect of CH4 on the vagus nerve. OBJECTIVES: Given its possible role in the parasympathetic nervous system, we aimed to study the relationship between breath CH4 and resting HR in humans. Additionally, we performed a longitudinal study analyzing the change in HR and its association with breath CH4 over time. METHODS: First, we reviewed 1,126 subjects and compared HR in subjects with detectable and undetectable breath CH4. Second, we performed a post hoc analysis of a randomized control trial to compare the change in HR for those who had an increase in breath CH4 versus those that had a decrease in breath CH4 over 14 weeks. Last, we assessed whether a larger decrease in CH4 is associated with a larger increase in HR over time. RESULTS: In the retrospective cohort, subjects with detectable CH4 had a lower HR compared to those with undetectable CH4 (73.0 ± 0.83 vs. 76.0 ± 0.44 beats/min, p = 0.01). In the post hoc analysis, a decrease in CH4 over time was associated with an increase in HR (median ∆ = 6.5 ± 8.32 beats/min, p = 0.0006). Last, we demonstrated a biological gradient whereby a larger drop in CH4 was associated with a greater increase in HR (R = -0.31, p = 0.03). CONCLUSION: Our findings suggest a potential role for the microbiome (and specifically CH4 from methanogens) to regulate HR. Considering these findings, mechanistic studies are warranted to further investigate this potential novel microbiome-neurocardiac axis.
Assuntos
Testes Respiratórios , Metano , Frequência Cardíaca , Humanos , Estudos Longitudinais , Estudos RetrospectivosRESUMO
BACKGROUND: Proton pump inhibitor (PPI) use is extremely common. PPIs have been suggested to affect the gut microbiome, and increase risks of Clostridium difficile infection and small intestinal bacterial overgrowth (SIBO). However, existing data are based on stool analyses and PPIs act on the foregut. AIMS: To compare the duodenal and stool microbiomes in PPI and non-PPI users. METHODS: Consecutive subjects presenting for upper endoscopy without colonoscopy were recruited. Current antibiotic users were excluded. Subjects taking PPI were age- and gender-matched 1:2 to non-PPI controls. Subjects completed medical history questionnaires, and duodenal aspirates were collected using a validated protected catheter. A subset also provided stool samples. Duodenal and stool microbiomes were analyzed by 16S rRNA sequencing. RESULTS: The duodenal microbiome exhibited no phylum-level differences between PPI (N = 59) and non-PPI subjects (N = 118), but demonstrated significantly higher relative abundances of families Campylobacteraceae (3.13-fold, FDR P value < 0.01) and Bifidobacteriaceae (2.9-fold, FDR P value < 0.01), and lower relative abundance of Clostridiaceae (88.24-fold, FDR P value < 0.0001), in PPI subjects. SIBO rates were not significantly different between groups, whether defined by culture (> 103 CFU/ml) or 16S sequencing, nor between subjects taking different PPIs. The stool microbiome exhibited significantly higher abundance of family Streptococcaceae (2.14-fold, P = 0.003), and lower Clostridiaceae (2.60-fold, FDR P value = 8.61E-13), in PPI (N = 22) versus non-PPI (N = 47) subjects. CONCLUSIONS: These findings suggest that PPI use is not associated with higher rates of SIBO. Relative abundance of Clostridiaceae was reduced in both the duodenal and stool microbiomes, and Streptococcaceae was increased in stool. The clinical implications of these findings are unknown.