Clinical experience with the use of anti-CdtB and anti-vinculin antibodies in patients with diarrhea in Mexico. / Experiencia clínica con el uso de los anticuerpos anti-CdtB y anti-vinculina en pacientes con diarrea en México.

INTRODUCTION: Circulating anti-CdtB/anti-vinculin antibodies have been validated as biomarkers to distinguish IBS-D from IBD, but there is no experience with them in Latin America. MATERIALS AND METHODS: The analysis was carried out on patients seen at a FGIDs/motility clinic over the last 7 months for diarrhea with abdominal pain and/or bloating who were tested for these antibodies. The patients were diagnosed according to the Rome III criteria or with organic disorders, and those presenting with IBS were further classified as post-infectious (PI) or non-PI-IBS. RESULTS: Thirty patients were studied. Positive biomarkers were found in IBS-D and IBS-D Overlap (58.8%) and IBS-M (33.3%), with no differences between PI-IBS (71.4%) vs. non-PI-IBS (41.7%) subjects (P=.21). There was no positivity in patients with other FGIDs or organic diarrhea, except for one with small intestinal bacterial overgrowth (SIBO). CONCLUSIONS: Our findings support the use of this test as a first-line diagnostic tool to confirm the presence of IBS-D/IBS-M according to the Rome III criteria.

The Mexican consensus on irritable bowel syndrome. / Consenso mexicano sobre el síndrome de intestino irritable.

BACKGROUND: Since the publication in 2009 of the Guidelines on the Diagnosis and Treatment of Irritable Bowel Syndrome of the Asociación Mexicana de Gastroenterología (2009 Guidelines), there have been significant advances in our knowledge of the epidemiology, pathophysiology, diagnosis, and treatment of this disease. AIMS: To present a consensus review of the most current knowledge of IBS, updating the 2009 Guidelines by incorporating new internationally published scientific evidence, with a special interest in Mexican studies. METHODS: The PubMed literature from January 2009 to March 2015 was reviewed and complemented through a manual search. Articles in English and Spanish were included and preference was given to consensuses, guidelines, systematic reviews, and meta-analyses. Statements referring to the different aspects of the disease were formulated and voted upon by 24 gastroenterologists employing the Delphi method. Once a consensus on each statement was reached, the quality of evidence and strength of recommendation were determined through the GRADE system. RESULTS: Forty-eight statements were formulated, updating the information on IBS and adding the complementary data that did not appear in the 2009 Guidelines regarding the importance of exercise and diet, diagnostic strategies, and current therapy alternatives that were analyzed with more stringent scientific vigor or that emerged within the last 5 years. CONCLUSIONS: We present herein a consensus review of the most relevant advances in the study of IBS, updating and complementing the 2009 Guidelines. Several studies conducted in Mexico were included.

Increase in Mexican and Latin American scientific articles on irritable bowel syndrome.

BACKGROUND: There is an implied perception that little scientific information on irritable bowel syndrome (IBS) comes out of Mexico and Latin America in the international medical literature, but the number and tendencies of articles from the region on IBS are not known. AIMS: To determine the number and type of Mexican and Latin American articles on IBS published between 1990-2015. METHODS: A systematic search of Medline was carried out employing the terms « Irritable Bowel Syndrome ¼ or its abbreviation (IBS). Mexico and every other Latin American country were added to specify the search. The articles were selected if they were published in Mexico and/or the rest of Latin America, if they were international papers on IBS in the region, or if they were written by Mexican and/or Latin American authors. In addition, the articles were classified into the following categories: Reviews/Editorials/Letters to the Editor (REV/ED), Epidemiology/Quality of Life/Psychosocial Factors (EPI/QOL), Diagnostic (DX), Treatment (TX), and Translational/Pathophysiologic (TRANS) studies. RESULTS: A total of 66 articles from Mexico and 47 from Latin America were identified, but only 87.7 and 48.9%, respectively, fit the selection criteria. Category distribution was: EPI/QOL: 36.2%, REV/ED: 27.5%, TRANS: 18.8, TX: 10%, and DX: 7.5% and was similar between Mexico and Latin America (p=0.33). The year 2005 saw an increase in the number of articles in Mexico, with a peak in 2010. The figures for Latin American articles remained stable over the years, with a peak in 2012. CONCLUSIONS: A noticeable increase has been observed over the last decade in the research conducted on IBS in Mexico and Latin America. Even though the EPI/QOL studies predominate, the sophistication of research is reflected in the TRANS studies that are in third place of frequency. The information referred to herein demonstrates maturity in the field, making it possible to carry out consensuses based on local data.

Microbiota, gastrointestinal infections, low-grade inflammation, and antibiotic therapy in irritable bowel syndrome: an evidence-based review.

BACKGROUND: Post-infectious irritable bowel syndrome (PI-IBS) prevalence, small intestinal bacterial overgrowth (SIBO), altered microbiota, low-grade inflammation, and antibiotic therapy in IBS are all controversial issues. AIMS: To conduct an evidence-based review of these factors. METHODS: A review of the literature was carried out up to July 2012, with the inclusion of additional articles as far as August 2013, all of which were analyzed through the Oxford Centre for Evidence-Based Medicine (OCEBM) system. RESULTS: 1.There is greater SIBO probability in IBS when breath tests are performed, but prevalence varies widely (2-84%). 2.The gut microbiota in individuals with IBS is different from that in healthy subjects, but a common characteristic present in all the patients has not been established. 3.The incidence and prevalence of PI-IBS varies from 9-10% and 3-17%, respectively, and the latter decreases over time. Bacterial etiology is the most frequent but post-viral and parasitic cases have been reported. 4.A sub-group of patients has increased enterochromaffin cells, intraepithelial lymphocytes, and mast cells in the intestinal mucosa, but no differences between PI-IBS and non-PI-IBS have been determined. 5.Methanogenic microbiota has been associated with IBS with constipation. 6.Rifaximin at doses of 400mg TID/10days or 550mg TID/14days is effective treatment for the majority of overall symptoms and abdominal bloating in IBS. Retreatment effectiveness appears to be similar to that of the first cycle. CONCLUSIONS: Further studies are required to determine the nature of the gut microbiota in IBS and the differences in low-grade inflammation between PI-IBS and non-PI-IBS. Rifaximin has shown itself to be effective treatment for IBS, regardless of prior factors.

Polar vectors as a method for evaluating the effectiveness of irritable bowel syndrome treatments: an analysis with pinaverium bromide 100mg plus simethicone 300mg po bid.

BACKGROUND: Irritable Bowel Syndrome (IBS) is a disorder characterized by abdominal pain or discomfort associated with changes in bowel habit. Currently there are no objective outcome measures for evaluating the effectiveness of treatments for this disorder. AIMS: To determine the usefulness of a method of analysis that employs polar vectors to evaluate the effectiveness of IBS treatments. METHODS: Data from a Phase IV clinical study with 1677 active IBS-Rome III patients who received 100mg of pinaverium bromide+300mg of simethicone (PB+S) po bid for a period of four weeks were used for the analysis. Using the Bristol Stool Scale as a reference, the consistency and frequency of each type of bowel movement were recorded weekly in a Bristol Matrix (BM) and the data were expressed as polar vectors. RESULTS: The analysis showed a differential response to the PB+S treatment among the IBS subtypes: in reference to the IBS with constipation subtype, the magnitude of the vector increased from 10.2 to 12.5, reaching maximum improvement at two weeks of treatment (p<0.05, Scheffé). In the IBS with diarrhea and mixed IBS subtypes, the magnitude of the vector decreased from 19 to 14 (p<0.05) and from 16.5 to 13 (p<0.05), respectively, with continuous improvement for a period of four weeks. There was no definable vectorial pattern in the unsubtyped IBS group. CONCLUSIONS: Analysis with polar vectors enables treatment response to be measured in different IBS subtypes. All the groups showed improvement with PB+S, but each one had its own characteristic response in relation to vector magnitude and direction. The proposed method can be implemented in clinical studies to evaluate the efficacy of IBS treatments.

Degree of concordance on the management of patients with gastroesophageal reflux disease. A study among specialists that are members of the Sociedad Latinoamericana de Neurogastroenterología (SLNG).

INTRODUCTION AND AIMS: Due to its different clinical manifestations, gastroesophageal reflux disease (GERD) requires diverse diagnostic and therapeutic interventions. The aim of the study was to evaluate the degree of agreement among Latin American specialists, with respect to the management of GERD. MATERIALS AND METHODS: A cross-sectional study was conducted through a survey with 42 statements (22 related to diagnosis and 20 to treatment) applied to 56 specialists from Latin America. There were 4 possible statement responses: in complete agreement, in partial agreement, in partial disagreement, and in complete disagreement. Reproducibility, level of agreement, and concordance were measured through the Kappa statistic. RESULTS: The response rate was 81% (47/56). General concordance was low, given that there was complete concordance in only 12 statements (28.6%). There was partial concordance in 22 statements (52.4%) and no concordance in 8 (19%). The following themes had the most disagreement: the performance of endoscopy before beginning treatment, the use of proton pump inhibitors (PPIs) in patients with extraesophageal symptoms and with no typical symptoms, and the combined use of PPIs and prokinetics. CONCLUSIONS: In the present study, we found that there was agreement among the Latin American specialists for the diagnosis and management of GERD in less than one-third of the recommendations considered standard. The low concordance could be related to the fact that the availability of diagnostic tools and medications, as well as the prevalence of GERD phenotypes, is different in each country.

Degree of concordance on the management of patients with gastroesophageal reflux disease. A study among specialists that are members of the Sociedad Latinoamericana de Neurogastroenterología (SLNG). / Grado de acuerdo en el manejo de pacientes con enfermedad por reflujo gastroesofágico. Un estudio entre especialistas miembros de la Sociedad Latinoamericana de Neurogastroenterología (SLNG).

INTRODUCTION AND AIMS: Due to its different clinical manifestations, gastroesophageal reflux disease (GERD) requires diverse diagnostic and therapeutic interventions. The aim of the study was to evaluate the degree of concordance among Latin American specialists, with respect to the management of GERD. MATERIALS AND METHODS: A cross-sectional study was conducted through a survey with 42 statements (22 related to diagnosis and 20 to treatment) applied to 56 specialists from Latin America. There were 4 possible statement responses: in complete agreement, in partial agreement, in partial disagreement, and in complete disagreement. Reproducibility, level of agreement, and concordance were measured through the Kappa statistic. RESULTS: The response rate was 81% (47/56). General concordance was low, given that there was complete concordance in only 12 statements (28.6%). There was partial concordance in 22 statements (52.4%) and no concordance in 8 (19%). The following themes had the most disagreement: the performance of endoscopy before beginning treatment, the use of proton pump inhibitors (PPIs) in patients with extraesophageal symptoms and with no typical symptoms, and the combined use of PPIs and prokinetics. CONCLUSIONS: In the present study, we found that there was agreement among the Latin American specialists for the diagnosis and management of GERD in less than one-third of the recommendations considered standard. The low concordance could be related to the fact that the availability of diagnostic tools and medications, as well as the prevalence of GERD phenotypes, are different in each country.

Heartburn and other related symptoms are independent of body mass index in irritable bowel syndrome.

BACKGROUND: increasing body mass index (BMI) is a risk factor for GERD but little is known about this association in the irritable bowel syndrome (IBS). AIMS: to determine the presence of heartburn and other related symptoms in relation with BMI in IBS. METHODS: volunteers (n = 483) answered the Rome II-Modular Questionnaire, and were divided into IBS and non-IBS (controls) groups. The frequency of heartburn, chest pain, epigastric pain, nausea, vomiting and belching was compared between the groups in the study sample and within three BMI categories. RESULTS: the IBS (23.7%) and controls (76.3%) were similar in gender (females: 68.1%), age (32.2 +/- 12.7 years), and BMI (25.4 +/- 4.4). Raw associations analysis showed that heartburn: OR: 1.62 (95%CI: 1.04-2.53), chest pain: 1.77 (1.13-2.77), epigastric pain: 1.75 (1.03-2.98) and nausea: 2.45 (1.10-5.32) were more frequent in IBS vs. controls. Meanwhile, according to BMI, in those with obesity, heartburn was more frequent in IBS and among those with overweight, epigastric pain and nausea were also more frequent in IBS. However, in an adjusted log linear model, no significant interaction was found between BMI and any other studied symptom and heartburn was found to be independent of IBS: 1,4 (0.9, 4.7). Finally, a logistic regression model found no interaction between BMI and the presence of heartburn or IBS. CONCLUSIONS: while heartburn and other reflux-related symptoms are more frequent in IBS than in controls, these associations are independent of BMI.

[Prevalence and clinical characteristics of the IBS subtypes according to the Rome III criteria in patients from a clinical, multicentric trial. A report from the Mexican IBS Working Group]. / Prevalencia y caracterización de los subtipos de SII según los criterios de Roma III, en un estudio clínico, multicéntrico. Informe del grupo mexicano de estudio para el SII.

BACKGROUND: In Mexico the prevalence of irritable bowel síndrome (IBS) using Rome II criteria varies between 16 and 35%. OBJECTIVE: To analyze the relative frequency of the IBS subtypes according to the Rome III criteria. METHODS: A multicentric study in 1677 IBS-Rome III patients that consulted private medical clinics. They all answered a structured interview by their physicians to determine the IBS subtype and to evaluate their symptoms intensity (Likert Scales). Patients self-evaluated their symptoms as well by using 10 cm visual analog scales for each one. RESULTS: Women represented 76.8% of the patients for a F:M ratio of 3.3:1. The relative frequencies of the IBS subtypes were IBS-M: 48.4%, IBS-E: 43.0%, IBS-D: 5.6% and IBS-U: 2.8% with females predominating among all. However, IBS-D included 1.7 to 2.4 times more men than any of the other subtypes. The IBS-M reported a higher frequency and intensity of halitosis and vomiting and a higher intensity of burping; while those with IBS-E reported a higher frequency and intensity of straining and the IBS-D more urgency for a bowel movement, fecal incontinence and mucous in the stools. CONCLUSIONS: In IBS-Rome III patients in Mexico, IBS-M is the most common subtype and is more commonly associated with dyspeptic symptoms while the IBS-E reported more outlet symptoms and the IBS-D fecal incontinence. There is a higher female predominance amongst all, however men are more likely to be in IBS-D.

[External validity of a relevant model for Irritable Bowel Syndrome (IBS) using chronic stress by water avoidance in Wistar rats]. / Validez externa de un modelo experimental para síndrome de intestino irritable (SII) mediante estrés crónico por evitación al agua en ratas Wistar.

BACKGROUND: Development of animal models has been one of the most remarkable achievements for Irritable Bowel Syndrome (IBS) research. These models need to exhibit face validity, construct and predictive validity, as well as internal (replicability) and external validity (generalizability). Among these models, chronic stress induced by water avoidance exposure (WA) has been validated in rats through increasing visceral hypersensitivity, motility impairment, anxiety and, colonic immune activity, all related to IBS. OBJECTIVE: To assess the external validity of WA indirectly on colonic motility in Wistar rats. METHOD: Ten male-Wistar rats were exposed to WA and compared with ten Wistar rats not exposed (controls). At the end of each exposure, the quantity of fecal pellets were determined and considered as a sign of autonomic regulation of colonic motility. Data was analyzed with a general linear model for repeated measures. RESULTS: Rats exposed to WA had higher number or pellets than controls: 7.46 ± 0.45 (95%CI: 6.51, 8.41) vs. 2.88 ± 0.45 (1.93, 3.83), p < 0.001. The higher number of pellets was related to WA exposure as there were no other significant interactions. In both groups, the number of pellets was higher during the first day and then decreased progressively. CONCLUSIONS: Chronic stress induced through WA in Wistar rats, exhibits external validity as an experimental model for IBS research and our findings of increased number of fecal pellets coincide with the appearance hypermotility related to IBS. The model is optimum for research studies on this disorder.

Beware: Gastrointestinal symptoms can be a manifestation of COVID-19. / Alerta: los síntomas gastrointestinales podrían ser una manifestación de la COVID-19.

BACKGROUND: There is an increasing number of reports on the presentation of gastrointestinal symptoms in cases of COVID-19. AIM: To review the studies reporting gastrointestinal symptoms in COVID-19. RESULTS: Fifteen articles (2,800 patients) were identified. Gastrointestinal symptom frequency varied from 3.0% to 39.6% and included diarrhea (7.5%), náusea (4.5%), anorexia (4.4%), vomiting (1.3%), abdominal pain (0.5%), and belching/reflux (0.3%). Those symptoms can be the first manifestation of COVID-19, but whether they reflect a better or worse prognosis, is controversial. The potential relation of the angiotensin converting enzyme 2 receptor in the digestive tract as an entry route for the virus is discussed. CONCLUSION: Gastrointestinal symptoms may be common in COVID-19, in some cases appearing as the first manifestation, even before fever and respiratory symptoms. Therefore, clinicians and gastroenterologists must be aware of those atypical cases during the current pandemic, as well as of the fecal-oral route and corresponding preventive measures.

Bowel symptoms in patients that receive proton pump inhibitors. Results of a multicenter survey in Mexico. / Síntomas intestinales en pacientes que reciben inhibidores de bomba de protones (IBP). Resultados de una encuesta multicéntrica en México.

INTRODUCTION: Proton pump inhibitors (PPIs) have been associated with small intestinal bacterial overgrowth (SIBO), which increases with prolonged PPI use, and SIBO has been associated with irritable bowel syndrome (IBS). OBJECTIVE: The aim of the present study was to study the prevalence of bowel symptoms in patients treated with PPIs in Mexico. METHODS: Gastroenterologists in 36 cities surveyed patients treated with PPIs, utilizing an ad hoc questionnaire to determine the presence of bowel symptoms and IBS. RESULTS: Two hundred and fifteen physicians interviewed 1,851 patients. PPI indications were gastritis (48.8%), gastroesophageal reflux (38.5%), peptic ulcer (6.2%), and others (6.5%). A total of 77.5% of the patients received treatment for ≤6 months and 11.9% for ≥1 year. Symptoms were reported in 92.3% of the patients: abnormal bowel habits (90%), bloating (82%), abdominal pain (63%), flatulence (58%), and abdominal discomfort (53%). A total of 67.5% of the patients fit the Rome III criteria for IBS. Symptoms presented in 55.9% of the patients before PPI intake and in 44.1% of the patients after PPI use (P<.005). Constipation (63.8%) predominated in the former, and diarrhea (56.5%) in the latter (P<.0001). The treatments prescribed for managing those symptoms were antispasmodics, antibiotics, prokinetics, and antiflatulents, but patients stated greater satisfaction with antibiotics (mainly rifaximin) (P<.0001). CONCLUSION: The association of PPIs with bowel symptoms and IBS is frequent in Mexico. Diarrhea and bloating predominate, and antibiotics produce the greatest treatment satisfaction, suggesting that SIBO or dysbiosis is the cause of the PPI-related bowel symptoms. However, that remains to be confirmed.

[Impact of the anxiety characteristics and depression on clinical aspects and quality of life in patients with irritable bowel syndrome]. / Impacto de los rasgos de ansiedad y depresión sobre aspectos clínicos y calidad de vida en pacientes con síndrome de intestino irritable.

BACKGROUND: Anxiety and depression have been related with seeking medical care by IBS patients, however their impact over the clinical characteristics and health related quality of life (HRQOL) of the patients, is unknown. AIMS: To evaluate the impact of these traits over the symptoms, number of consultations and HRQOL in IBS. METHODS: Consecutive moderate to severe IBS-Rome I patients that consulted a reference center in Mexico City, answered the HAD, a Bowel Symptom Questionnaire and the SF-36. Patients were compared according to the presence or absence of anxiety or depression. RESULTS: Anxiety was found in 70%, depression in 46% and both traits among 40%. The majority of those with depression were single compared to a married majority in those without this trait (p = 0.03). Those with anxiety (p = 0.03) and depression (p = 0.006) reported more number of days with abdominal pain/ discomfort and both traits (p = 0.000) were associated with a higher frequency of fullness, distention, abdominal pain, incomplete evacuation, abnormal bowel movements and lower HRQOL. Patients with anxiety reported a more severe IBS and those with depression a higher frequency of diarrhea predominance (p = 0.047). CONCLUSIONS: Traits anxiety and depression negatively impacted over the number of days, symptom frequency and HRQOL of patients with moderate to severe IBS. More studies are needed to determine if these psychological symptoms are causing these outcomes or if the gastrointestinal symptoms and poor HRQOL are triggering anxiety and depression in IBS.

Colonic immune cells in irritable bowel syndrome: A systematic review and meta-analysis.

BACKGROUND & AIMS: Increases in mucosal immune cells have frequently been observed in irritable bowel syndrome (IBS) patients. However, this finding is not completely consistent between studies, possibly due to a combination of methodological variability, population differences and small sample sizes. We performed a meta-analysis of case-control studies that compared immune cell counts in colonic biopsies of IBS patients and controls. METHODS: PubMed and Embase were searched in February 2017. Results were pooled using standardized mean difference (SMD) and were considered significant when zero was not within the 95% confidence interval (CI). Heterogeneity was assessed based on I2 statistics where I2  ≤ 50% and I2  > 50% indicated fixed and random effect models, respectively. KEY RESULTS: Twenty-two studies on 706 IBS patients and 401 controls were included. Mast cells were increased in the rectosigmoid (SMD: 0.38 [95% CI: 0.06-0.71]; P = .02) and descending colon (SMD: 1.69 [95% CI: 0.65-2.73]; P = .001) of IBS patients. Increased mast cells were observed in both constipation (IBS-C) and diarrhea predominant IBS (IBS-D). CD3+ T cells were increased in the rectosigmoid (SMD: 0.53 [95% CI: 0.21-0.85]; P = .001) and the descending colon of the IBS patients (SMD: 0.79, 95% CI [0.28-1.30]; P = .002). This was possibly in relation to higher CD4+ T cells in IBS (SMD: 0.33 [95% CI: 0.01-0.65]; P = .04) as there were no differences in CD8+ T cells. CONCLUSIONS & INFERENCES: Mast cells and CD3+ T cells are increased in colonic biopsies of patients with IBS vs non-inflamed controls. These changes are segmental and sometimes IBS-subtype dependent. The diagnostic value of the quantification of colonic mucosal cells in IBS requires further investigation.

The Mexican consensus on chronic constipation. / Consenso mexicano sobre estreñimiento crónico.

INTRODUCTION: Significant advances have been made in the knowledge and understanding of the epidemiology, pathophysiology, diagnosis, and treatment of chronic constipation, since the publication of the 2011 guidelines on chronic constipation diagnosis and treatment in Mexico from the Asociación Mexicana de Gastroenterología. AIMS: To present a consensus review of the current state of knowledge about chronic constipation, providing updated information and integrating the new scientific evidence. METHODS: Three general coordinators reviewed the literature published within the time frame of January 2011 and January 2017. From that information, 62 initial statements were formulated and then sent to 12 national experts for their revision. The statements were voted upon, using the Delphi system in 3 voting rounds (2 electronic and one face-to-face). The statements were classified through the GRADE system and those that reached agreement >75% were included in the consensus. RESULTS AND CONCLUSIONS: The present consensus is made up of 42 final statements that provide updated knowledge, supplementing the information that had not been included in the previous guidelines. The strength of recommendation and quality (level) of evidence were established for each statement. The current definitions of chronic constipation, functional constipation, and opioid-induced constipation are given, and diagnostic strategies based on the available diagnostic methods are described. The consensus treatment recommendations were established from evidence on the roles of diet and exercise, fiber, laxatives, new drugs (such as prucalopride, lubiprostone, linaclotide, plecanatide), biofeedback therapy, and surgery.