Characterization of an At-Risk Population for Nonalcoholic Fatty Liver Disease (NAFLD) in a Primary Care Setting Along the U.S.-Mexico Border.

INTRODUCTION: This study aimed to determine the burden of suspected nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) in a predominantly Hispanic patient population and explore the utility of the American Gastroenterological Association's NAFLD Clinical Care Pathway (CCP). METHODOLOGY: Electronic medical records (n = 223) were used to divide patients into risk groups based on the amount of metabolic risk factors they presented, diabetic status, or if they presented other liver diseases. Fribosis-4 (FIB-4) scores were used to determine the risk for advanced fibrosis. RESULTS: Most patients (83.8%) were considered at risk for NAFLD based on CCP criteria, and about a third of patients (33.2%) were found to be at indeterminate (n = 60; 26.9%) or high risk (n = 14; 6.3%) for advanced fibrosis. Most indeterminate-risk patients (78.3%) were not referred for liver imaging. DISCUSSION: This study demonstrates the potential of the CCP as a corrective tool that could help to better identify and screen patients at risk for NAFLD.

Poorly Cohesive Carcinoma of the Nonampullary Small Bowel: A Rare Cause of Recurrent Small Bowel Obstruction.

Poorly cohesive carcinoma (PCC) is an uncommon neoplasm characterized by tumorous cells exhibiting a lack of adhesion. PCC has been reported rarely in the small intestine other than at the ampulla of Vater. We present a 40-year-old man with recurrent abdominal pain and small bowel obstruction. Imaging revealed an abnormal appearing distal small bowel, with only nonspecific mucosal changes discovered on antegrade and retrograde enteroscopy. On subsequent diagnostic laparoscopy, an ileal mass was found and resected with histopathology showing PCC with signet ring formation. This is an aggressive cancer with a worse prognosis than other small bowel adenocarcinomas.

Implementation and Evaluation of a Large Community-Based Colorectal Cancer Screening Program.

CONTEXT: Colorectal cancer (CRC) screening can significantly reduce incidence and mortality; however, screening rates are suboptimal. The lowest rates are among those with no usual source of care and the uninsured. OBJECTIVE: We describe the implementation and evaluation of a community-based CRC screening program from 2012 to 2015 designed to increase screening within a predominantly Hispanic US-Mexico border population. METHODS: The multicomponent, evidence-based program provided in-person, bilingual, culturally tailored health education facilitated by community health workers, no-cost primarily stool-based testing and diagnostic colonoscopy, and navigation. We recruited uninsured individuals due for CRC screening from clinics and community sites. An extensive qualitative and quantitative program process and outcome evaluation was conducted. RESULTS: In total, 20 118 individuals were approached, 8361 were eligible for screening; 74.8% completed screening and 74.6% completed diagnostic testing; 14 cancers were diagnosed. The mean age of participants was 56.8 years, and the majority were Hispanic, female, and of low socioeconomic status. The process evaluation gathered information that enabled effective program implementation and demonstrated effective staff training, compliance with processes, and high patient satisfaction. CONCLUSIONS: This program used a population-based approach focusing on uninsured individuals and proved successful at achieving high fecal immunochemical test kit return rates and colonoscopy completion rates. Key factors related to its success included tailoring the intervention to our priority population, strong partnerships with community-based sites and clinics, expertise in clinical CRC screening, and an active community advisory board. This program can serve as a model for similar populations along the border to increase CRC screening rates among the underserved.

Disorders of Gut-brain Interaction on the US-Mexico Border: A Survey Using Rome IV Criteria.

BACKGROUND: Disorders of gut-brain interaction (DGBI) cause a substantial health burden. Herein we studied the prevalence and characteristics of DGBI and symptoms of bloating/distension in El Paso, Texas on the US-Mexico border, providing a unique opportunity to study the effects of acculturation. METHODS: Subjects from community centers completed the Rome IV questionnaire for DGBI, short acculturation scale for Hispanics questionnaire, and bloating/distention Pictograms. Data were presented as prevalence (95% CI) and compared using χ 2 . RESULTS: Of 216 participants, 197 (127 Hispanics, 90 with English acculturation) were included and 177 completed the Pictograms. Fifty-one [25.9% (20 to 32.6)] subjects fulfilled the criteria for at least one DGBI. Globus and functional dyspepsia were the most common upper DGBI, each in [3.0% (1.1 to 6.5)]. Unspecified functional bowel disorders [8.6% (5.1 to 13.5)], followed by functional abdominal bloating/distention [8.1% (4.7 to 12.9], and irritable bowel syndrome [6.1% (3.2 to 10.4] were the most common functional bowel disorder. Ninety-one (51.4%) reported bloating and/or distension with Pictograms; more frequently in those with DGBI (80.9% vs 40.8%, P < 0.001). Bloating and/or distension were reported by Pictograms in 30% of those not reporting it in the Rome IV Questionnaire. There were no differences based on acculturation or in Hispanics versus non-Hispanics. CONCLUSIONS: On the US-Mexico border, we found a lower prevalence of DGBI than in the US or Mexico. Functional abdominal bloating/distention was more prevalent on the US-Mexico border than in either country. Bloating/distension was more commonly reported with Pictograms than with verbal descriptors. There were no differences between Hispanics and non-Hispanics, suggesting shared environmental/acquired including dietary factors as the underlying mechanisms.

Plasma endocannabinoids and cannabimimetic fatty acid derivatives are altered in cyclic vomiting syndrome: The effects of sham feeding.

Cyclic vomiting syndrome (CVS) is an underdiagnosed disorder of the gut-brain interaction. Our understanding of the pathophysiology of CVS is evolving. Here, we tested the hypotheses that: (1) the levels of endocannabinoids and related lipids are altered in CVS, and (2) cephalic-vagal stimulation drive changes in endolipid levels. Ten adult patients with CVS and eight healthy controls were included. Indirect measurements of parasympathetic (RFa) functions were performed with spectral analysis of heart rate variability and respiratory activity. Plasma levels of endocannabinoids and related lipids were measured at baseline and during a sham feeding. Values are reported as mean ± standard error of the mean and compared using t-test or ANOVA. CVS patients had a lower parasympathetic tone and response to the Valsalva maneuver and deep breathing than the controls. The baseline 2-Arachidonoylglycerol (2-AG) had a significantly higher concentration in CVS (5.9e-008 ± 3.7e-008 mol/L) than control (3.7e-008 ± 1.3e-008 mol/; p < 0.05). Sham feeding did not change the concentration of 2-AG. 2-oleoylglycerol (2-OG) was significantly higher in CVS than control and did not change with sham feeding. Levels of N-acylethanolamines, including anandamide (AEA), were not different in CVS vs control. After sham feeding, AEA showed a trend toward increasing (p = 0.08) in CVS, but not in control. With sham feeding, palmitoyl ethanolamine significantly increased in both CVS and control groups; oleoyl ethanolamine in CVS only, and stearoyl ethanolamine in the control group. Levels of endocannabinoids and related lipids are altered in CVS patients. Sham feeding affects endogenous signaling lipids in a disease and time-dependent manner.

Nationwide analysis of incidence and predictors of 30-day readmissions in patients with decompensated cirrhosis.

Background and objective: Cirrhosis is the number one cause of non-cancer deaths among gastrointestinal diseases and is responsible for significant morbidity and healthcare utilisation. The objectives were to measure the 30-day readmissions rate following index hospitalisation, to determine the predictors of readmission, and to estimate the cost of 30-day readmission in patients with decompensated cirrhosis. Methods: We performed a retrospective cohort study of patients with decompensated cirrhosis using 2014 Nationwide Readmission Database from January to November. Decompensated cirrhosis was identified based on the presence of at least one of the following: ascites, hepatic encephalopathy, variceal bleeding, spontaneous bacterial peritonitis and hepatorenal syndrome. We excluded patients less than 18 years of age, pregnant patients, patients with missing length of stay data, and those who died during the index admission. Results: Among 57 305 unique patients with decompensated cirrhosis, the 30-day readmission rate was 23.2%. The top three predictors of 30-day readmission were leaving against medical advice (AMA), ascites and acute kidney injury, which increased the risk of readmission by 47%, 22% and 20%, respectively. Index admission for variceal bleeding was associated with a lower 30-day readmission rate by 18%. The estimated total cost associated with 30-day readmission in our study population was US$234.4 million. Conclusion: In a nationwide population study, decompensated cirrhosis is associated with a 30-day readmission rate of 23%. Leaving AMA, ascites and acute kidney injury are positively associated with readmission. Targeted interventions and quality improvement efforts should be directed toward these potential risk factors to reduce readmissions.

A Perfect Storm: Abdominal Pain and Ileus Explained by Acute Intermittent Porphyria Caused by Prehospitalization and Intrahospitalization Factors.

Acute intermittent porphyria (AIP) is a rare autosomal dominant inherited disease, predominantly seen in female patients, caused by mutations in the hydroxymethylbilane synthase gene. When impaired, elevated heme biosynthesis precursor levels accumulate in the liver, resulting in neurological symptoms, psychiatric disturbances, darkened urine color, abdominal pain, nausea, vomiting, and ileus. We present a 22-year-old Hispanic female with diffuse abdominal pain and no bowel movements for 8 days. She reported recent antibiotic and oral contraceptive pill use. Computerized tomography of her abdomen revealed a dilated small bowel and marked colonic distension. A colonoscopy found mild nonspecific inflammation in the rectosigmoid and terminal ileum. Her abdominal pain persisted despite interventions and improvements in appetite, bowel movements, abdominal imaging, and treatment of an identified Clostridium difficile infection. A random urine porphobilinogen was then obtained and found to be elevated. Fractionation of plasma and urine porphyrins was suggestive of AIP. Her symptoms improved with 3 days of intravenous (IV) hematin and IV dextrose. This is a unique case of a rare disease due to her clinical presentation with ileus, unremarkable past medical history, family history, and the prehospitalization and intrahospitalization factors that likely exacerbated the patient AIP.

Gastrointestinal symptoms and the severity of COVID-19: Disorders of gut-brain interaction are an outcome.

BACKGROUND: Many of the studies on COVID-19 severity and its associated symptoms focus on hospitalized patients. The aim of this study was to investigate the relationship between acute GI symptoms and COVID-19 severity in a clustering-based approach and to determine the risks and epidemiological features of post-COVID-19 Disorders of Gut-Brain Interaction (DGBI) by including both hospitalized and ambulatory patients. METHODS: The study utilized a two-phase Internet-based survey on: (1) COVID-19 patients' demographics, comorbidities, symptoms, complications, and hospitalizations and (2) post-COVID-19 DGBI diagnosed according to Rome IV criteria in association with anxiety (GAD-7) and depression (PHQ-9). Statistical analyses included univariate and multivariate tests. RESULTS: Five distinct clusters of symptomatic subjects were identified based on the presence of GI symptoms, loss of smell, and chest pain, among 1114 participants who tested positive for SARS-CoV-2. GI symptoms were found to be independent risk factors for severe COVID-19; however, they did not always coincide with other severity-related factors such as age >65 years, diabetes mellitus, and Vitamin D deficiency. Of the 164 subjects with a positive test who participated in Phase-2, 108 (66%) fulfilled the criteria for at least one DGBI. The majority (n = 81; 75%) were new-onset DGBI post-COVID-19. Overall, 86% of subjects with one or more post-COVID-19 DGBI had at least one GI symptom during the acute phase of COVID-19, while 14% did not. Depression (65%), but not anxiety (48%), was significantly more common in those with post-COVID-19 DGBI. CONCLUSION: GI symptoms are associated with a severe COVID-19 among survivors. Long-haulers may develop post-COVID-19 DGBI. Psychiatric disorders are common in post-COVID-19 DGBI.

Colorectal neoplasia prevalence in a predominantly Hispanic community: Results from a colorectal cancer screening program in Texas.

BACKGROUND: A community-based, colorectal cancer (CRC) screening program for uninsured/underinsured individuals was successfully implemented in El Paso, Texas to increase CRC screening rates. Our aim was to determine the colorectal neoplasia prevalence among program participants and between screening groups. METHODS: We retrospectively reviewed participant records from 2012 to 2017. Average-risk patients were first screened with a fecal immunochemical test (FIT) and included if positive. Above average-risk patients due to a family history of CRC were referred directly for screening colonoscopy. Patients were excluded if experiencing melena or hematochezia or had a personal history of colon polyps or CRC. RESULTS: Of the 638 screening colonoscopies performed, 59.4% were in FIT-positive subjects and 40.6% were in subjects with a family history of CRC. Patients were predominantly female (72.9%), aged 50-65 years (84.2%), Hispanic (97.9%), and born in Mexico (92.4%). Overall, the detection rate for polyps, adenomas, and advanced adenomas was 46.2%, 34.3%, and 11.1%, respectively. Fifteen patients had adenocarcinoma (2.4%). Compared with colonoscopies in patients with a family history, FIT-positive patients demonstrated a higher prevalence of polyps (PR 1.39, 95% CI 1.09-1.78), adenomas (PR 1.55, 95% CI 1.15-2.07), advanced adenomas (PR 3.04, 95% CI 1.67-5.56). CONCLUSIONS: This community-based CRC screening program in an enriched cohort of predominantly Mexican Americans was effective in identifying colorectal neoplasia and cancer. Additionally, there was an increased prevalence of colorectal neoplasia in average-risk, FIT-positive patients undergoing screening colonoscopy compared with above average-risk patients with a family history of CRC. Similar screening programs would likely benefit at-risk populations.

Endoscopic Treatment of Black Esophagus With Fully Covered Metallic Stent.

Acute esophageal necrosis (AEN) is a condition characterized by black appearance and inflammation of the esophagus. Our patient developed AEN presenting in the setting of alcohol intoxication and extensive inferior vena cava thrombosis. Esophagogastroduodenoscopy showed blood and black discoloration of the middle and lower esophagus with oozing. To control bleeding, a self-expandable fully covered metallic esophageal stent was placed. Multiple studies and reviews agree that the initial management for AEN is supportive care, resuscitation, and proton pump inhibitors to protect the esophageal mucosa from injury from acid reflux. Our case highlights the benefits of esophageal stent placement to manage AEN with active bleeding.

Latin Americans and US Hispanics show differences in IBD phenotype: a systematic review with meta-analysis.

Latin America has experienced a rise in the prevalence and incidence of inflammatory bowel disease (IBD). Differences in IBD phenotype between Hispanics in Latin America and those in the USA have not been described. We conducted a systematic review with meta-analysis of population-based and cohort studies comparing the phenotype of ulcerative colitis (UC) and Crohn's disease (CD) in Latin Americans and US Hispanics. A systematic search was conducted up to March 2019 using MEDLINE, EMBASE and Google Scholar. Inclusion criterion includes studies describing IBD phenotype in Latin Americans or in US Hispanics. Exclusion criterion includes prevalence or incidence studies not describing phenotype. A random effects model was chosen "a priori" for analysis of pooled proportions. A total of 46 studies were included from Latin America and 7 studies from the USA. The predominant IBD subtype in Latin America was UC with a more balanced UC:CD ratio noted in Puerto Rico (0.53) and Brazil (0.56). UC-related extensive colitis was more common in US Hispanics (0.64) than in Latin Americans (0.38), p<0.001. CD phenotype was similar between US Hispanics and Latin Americans. UC is the predominant IBD subtype in Latin America, with the exception of Puerto Rico and Brazil which demonstrate a more balanced UC:CD ratio. In UC, extensive colitis was more frequently seen in US Hispanics than in Latin Americans. CD phenotype was similar in both US Hispanics and Latin Americans.

Endoscopic Bariatric Interventions in Patients with Chronic Liver Disease.

Obesity and its associated comorbidities are rapidly increasing in the US population. Therefore, metabolic associated fatty liver disease (MAFLD), previously known as nonalcoholic fatty liver disease (NAFLD), has become a leading indication for liver transplantation. Lifestyle modifications as a sole therapy have been insufficient to reduce the burden of chronic liver disease secondary to MAFLD. Endoscopic bariatric interventions (EBI) appear to be safe and effective therapies for obesity and chronic liver disease secondary to MAFLD. Gastric EBI include endoscopic sleeve gastroplasty (ESG) and intragastric balloons (IGB). Small bowel EBI are also evolving in the field of bariatric endoscopy.

Endoscopic Treatment of Esophageal Varices.

Acute variceal bleeding is a complication of portal hypertension, usually due to cirrhosis, with high morbidity and mortality. There are 3 scenarios for endoscopic treatment of esophageal varices: prevention of first variceal bleed, treatment of active variceal bleed, and prevention of rebleeding. Patients with cirrhosis should be screened for esophageal varices. Recommended endoscopic therapy for acute variceal bleeding is endoscopic variceal banding. Although banding is the first-choice treatment, sclerotherapy may have a role. Treatment with Sengstaken-Blakemore tube or self-expanding covered metallic esophageal stent can be used for acute variceal bleeding refractory to standard pharmacologic and endoscopic therapy.

Liver abnormalities in pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a cardiopulmonary disease with high mortality. In recent years, it has been recognized that PAH is a multi-organ system disease, involving the systemic circulation, kidneys, skeletal muscles, and the central nervous system, among others. Right heart failure produces congestive hepatopathy, a disease state that has direct consequences on liver biochemistry, histology, and systemic glucose and lipid metabolism. This article aims to summarize the consequences of congestive hepatopathy with an emphasis on liver biochemistry, histology, and PAH-targeted therapy. Furthermore, PAH-specific changes in glucose and lipid metabolism will be discussed.

Autoimmune Hepatitis in a Patient With Common Variable Immunodeficiency.

Common variable immunodeficiency (CVID) is characterized by defective immunoglobulin synthesis because of impaired B-cell function. Liver abnormalities including autoimmune hepatitis (AIH) have been described in up to 10% of patients. We report a 27-year-old woman with CVID who presented with liver dysfunction secondary to AIH. AIH is both uncommon and challenging diagnostically in patients with CVID because they have low IgG levels and often have low or undetectable autoantibody levels. Liver biopsy and response to therapy play an important role in establishing the diagnosis. Corticosteroids are the mainstay of therapy, with or without immune modulators.

Massive Hematochezia from a Large Bleeding Duodenal Diverticulum.

BACKGROUND: Duodenal diverticula are a rare cause of gastrointestinal (GI) bleeding despite being a common finding in the GI tract. We present a case of a patient who had massive hematochezia due to a complex duodenal diverticulum. Case Presentation. A 74-year-old Hispanic female presented initially with generalized weakness. During admission, the patient had an episode of a large amount of hematochezia and had to be transferred to the intensive care unit (ICU). Upper endoscopy was done using a forward-viewing endoscope which revealed a bleeding complex duodenal diverticulum. Successful hemostasis was achieved through epinephrine injection followed by placement of hemostatic clips. CONCLUSION: Although rare, gastroenterologists need to be aware of duodenal diverticulum as a possible cause of gastrointestinal bleed. It could be life-threatening, and thus, prompt diagnosis and management is necessary.

Comparative effectiveness of five fecal immunochemical tests using colonoscopy as the gold standard: study protocol.

BACKGROUND: There are nearly 50,000 colorectal cancer (CRC) deaths in the United States each year. CRC is curable if detected in its early stages. Fecal immunochemical tests (FITs) can detect precursor lesions and many can be analyzed at the point-of-care (POC) in physician offices. However, there are few data to guide test selection. Broader use of FITs could make CRC screening more accessible, especially in resource-poor settings. METHODS: A total of 3600 racially and ethnically diverse individuals aged 50 to 85 years having either a screening or surveillance colonoscopy will be recruited. Each participant will complete five FITs on a single stool sample. Test characteristics for each FIT for advanced colorectal neoplasia (ACN) will be calculated using colonoscopy as the gold standard. RESULTS: We have complete data from a total of 2990 individuals. Thirty percent are Latino and 5.3% are black/African American. We will present full results once the study is completed. CONCLUSIONS: Our focus in this study is how well FITs detect ACN, using colonoscopy as the gold standard. Four of the five FITs being used are POC tests. Although FITs have been shown to have acceptable performance, there is little data to guide which ones have the best test characteristics and colonoscopy is the main CRC screening test used in the United States. Use of FITs will allow broader segments of the population to access CRC screening because these tests require no preparation, are inexpensive, and can be collected in the privacy of one's home. Increasing CRC screening uptake will reduce the burden of advanced adenomas and colorectal cancer.

Evaluation of the diagnostic and therapeutic utility of retrograde through-the-scope balloon enteroscopy and single-balloon enteroscopy.

BACKGROUND: Retrograde single balloon enteroscopy (SBE) is a minimally invasive procedure which is less frequently performed compared with antegrade SBE. There are few studies on the retrograde through-the-scope enteroscopy (TTSE), a novel technique for evaluation of the small bowel. AIM: To compare the clinical utility and safety of retrograde TTSE with retrograde SBE. METHODS: Clinical data and complications of retrograde TTSE (2014-2018) and retrograde SBE (2011-2018) performed in a community hospital were reviewed and presented as mean ± SD or frequency (%) and compared using proper statistical tests. Technical success was defined as insertion of the enteroscope > 20 cm beyond ileocecal valve. RESULTS: Data obtained from 54 retrograde SBE in 49 patients and 27 retrograde TTSE in 26 patients were studied. The most common indication for retrograde enteroscopy was iron deficiency anemia (41 patients) followed by gastrointestinal bleeding (37 patients), and chronic diarrhea (7 patients). The duration of retrograde SBE procedure (91.9 ± 34.2 min) was significantly longer compared with retrograde TTSE (70.5 ± 30.7 min) (P = 0.04). Technical success was comparable in TTSE [23/27 (85.2%)] and SBE [41/54 (75.9%) (P = 0.33)]. The mean depth of insertion beyond the ileocecal valve in retrograde SBE (92.5 ± 70.0 cm) tended to be longer compared with retrograde TTSE (64.6 ± 49.0 cm) (P = 0.08). No complication was observed in this study. CONCLUSION: Both retrograde TTSE and retrograde SBE are feasible and safe. Retrograde TTSE takes a shorter time and has a comparable technical success with SBE. TTSE has a lower capacity of small bowel insertion.

Segmental Withdrawal During Screening Colonoscopy Does Not Increase Adenoma Detection Rate.

OBJECTIVES: The aim of this study was to compare a standard versus segmental withdrawal during screening colonoscopy and its effect on the adenoma detection rate (ADR). METHODS: We performed a single-center clinical trial of average-risk patients 50 years of age and older undergoing screening colonoscopy. Patients were randomized into four groups: a standard withdrawal of at least 6 or 8 minutes and a segmental withdrawal, in which ≥3 or ≥4 minutes were dedicated to the right side of the colon, with a minimum withdrawal time of at least 6 or 8 minutes, respectively. RESULTS: There were 311 patients in the study. There was no difference in ADR between the standard and segmental groups (relative ratio [RR] 0.91, P = 0.50), even after stratifying for right-sided adenomas. During standard withdrawal, an increased continuous withdrawal time was associated with a higher ADR (RR 1.08, P <0.001) and total adenomas per patient (RR 1.12, P < 0.001). A binary analysis of ≥8 minutes or <8 minutes withdrawal was associated with an increased adenomas per colonoscopy (RR 1.86, P = 0.04). These differences were not observed in the segmental group. CONCLUSIONS: Overall, there was no benefit from a segmental withdrawal protocol on ADR, but this may have been the result of the inherent limitations in the study design. After sensitivity analysis, a segmental withdrawal protocol led to an improvement in the detection of adenomas per colonoscopy and polyps per colonoscopy. A larger sample size is needed to confirm these findings.

Mast cells are increased in the small intestinal mucosa of patients with irritable bowel syndrome: A systematic review and meta-analysis.

BACKGROUND: Colonic mast cells have been proposed to be related to the pathophysiology of irritable bowel syndrome (IBS). Whether mast cell counts are altered in the small intestine, a less-explored region in patients with IBS is not completely clear. METHODS: PubMed and EMBASE were searched for case-control studies on mast cell count/density in the small intestine of patients with IBS vs controls through February 2019. Mast cell counts were separately analyzed in the duodenum, jejunum, and ileum. Data were pooled using the standardized mean difference (SMD) method. When zero was not within the 95% confidence interval (CI), the SMD was considered significant. KEY RESULTS: Data from 344 patients with IBS and 229 healthy controls from three studies in the duodenum, six in the jejunum, and five in the ileum were pooled in this meta-analysis. The number of mast cells was significantly higher in the ileum (SMD: 1.78 [95% CI: 0.89, 2.66]) of patients with IBS. Mast cell counts were not significantly different in the duodenum (SMD: 0.81 [-0.06, 1.67]) or the jejunum (SMD: 0.58 [-0.03, 1.19]) of patients with IBS vs healthy controls. CONCLUSIONS AND INFERENCES: Mast cells are increased in the small intestine of IBS vs controls, mainly in the ileum. Future studies should address whether such findings are IBS subtype or gender-dependent. Methodological variations, single-center bias, and the limited number of studies included in this meta-analysis may affect the final results.