Diagnosis and management of chronic constipation in adults

Constipation is a heterogeneous, polysymptomatic, multifactorial disease. Acute or transient constipation can be due to changes in diet, travel or stress, and secondary constipation can result from drug treatment, neurological or metabolic conditions or, rarely, colon cancer. A diagnosis of primary chronic constipation is made after exclusion of secondary causes of constipation and encompasses several overlapping subtypes. Slow-transit constipation is characterized by prolonged colonic transit in the absence of pelvic floor dysfunction. This subtype of constipation can be identified using either the radio-opaque marker test or wireless motility capsule test, and is best treated with laxatives such as polyethylene glycol or newer agents such as linaclotide or lubiprostone. If unsuccessful, subspecialist referral should be considered. Dyssynergic defecation results from impaired coordination of rectoanal and pelvic floor muscles, and causes difficulty with defecation. The condition can be identified using anorectal manometry and balloon expulsion tests and is best managed with biofeedback therapy. Opioid-induced constipation is an emerging entity, and several drugs including naloxegol, methylnaltrexone and lubiprostone are approved for its treatment. In this Review, we provide an overview of the burden and pathophysiology of chronic constipation, as well as a detailed discussion of the available diagnostic tools and treatment options.

Diagnosis and Treatment of Dyssynergic Defecation

Dyssynergic defecation is common and affects up to one half of patients with chronic constipation. This acquired behavioral problem is due to the inability to coordinate the abdominal and pelvic floor muscles to evacuate stools. A detailed history, prospective stool diaries, and a careful digital rectal examination will not only identify the nature of bowel dysfunction, but also raise the index of suspicion for this evacuation disorder. Anorectal physiology tests and balloon expulsion test are essential for a diagnosis. Newer techniques such as high-resolution manometry and magnetic resonance defecography can provide mechanistic insights. Recently, randomized controlled trials have shown that biofeedback therapy is more effective than laxatives and other modalities, both in the short term and long term, without side effects. Also, symptom improvements correlated with changes in underlying pathophysiology. Biofeedback therapy has been recommended as the first-line of treatment for dyssynergic defecation. Here, we provide an overview of the burden of illness and pathophysiology of dyssynergic defecation, and how to diagnose and treat this condition with biofeedback therapy.

2019 Seoul Consensus on Esophageal Achalasia Guidelines

Esophageal achalasia is a primary motility disorder characterized by insufficient lower esophageal sphincter relaxation and loss of esophageal peristalsis. Achalasia is a chronic disease that causes progressive irreversible loss of esophageal motor function. The recent development of high-resolution manometry has facilitated the diagnosis of achalasia, and determining the achalasia subtypes based on high-resolution manometry can be important when deciding on treatment methods. Peroral endoscopic myotomy is less invasive than surgery with comparable efficacy. The present guidelines (the "2019 Seoul Consensus on Esophageal Achalasia Guidelines") were developed based on evidence-based medicine; the Asian Neurogastroenterology and Motility Association and Korean Society of Neurogastroenterology and Motility served as the operating and development committees, respectively. The development of the guidelines began in June 2018, and a draft consensus based on the Delphi process was achieved in April 2019. The guidelines consist of 18 recommendations: 2 pertaining to the definition and epidemiology of achalasia, 6 pertaining to diagnoses, and 10 pertaining to treatments. The endoscopic treatment section is based on the latest evidence from meta-analyses. Clinicians (including gastroenterologists, upper gastrointestinal tract surgeons, general physicians, nurses, and other hospital workers) and patients could use these guidelines to make an informed decision on the management of achalasia.

Effect of Structural Individual Low-FODMAP Dietary Advice vs. Brief Advice on a Commonly Recommended Diet on IBS Symptoms and Intestinal Gas Production

A low fermentable oligosaccharide, disaccharide, monosaccharide, and polyol (FODMAP) diet has been recommended for irritable bowel syndrome (IBS) patients. This study compared the efficacy of two types of dietary advice: (1) brief advice on a commonly recommended diet (BRD), and (2) structural individual low-FODMAP dietary advice (SILFD). Patients with moderate-to-severe IBS were randomized to BRD or SILFD groups. Gastrointestinal symptoms, 7-day food diaries, and post-prandial breath samples were evaluated. The SILFD included (1) identifying high-FODMAP items from the diary, (2) replacing high-FODMAP items with low-FODMAP ones by choosing from the provided menu. The BRD included reducing traditionally recognized foods that cause bloating/abdominal pain and avoidance of large meals. Responders were defined as those experiencing a ≥30% decrease in the average of daily worst abdominal pain/discomfort after 4 weeks. Sixty-two patients (47 F, age 51 ± 14 years), BRD (n = 32) or SILFD (n = 30), completed the studies. Eighteen (60%) patients in SILFD vs. 9 (28%) in the BRD group fulfilled responder criteria (p = 0.001). Global IBS symptom severity significantly improved and the number of high-FODMAP items consumed was significantly decreased after SILFD compared to BRD. Post-prandial hydrogen (H₂) breath production after SILFD was significantly lower than was seen after BRD (p < 0.001). SILFD was more effective than BRD. This advice method significantly reduced FODMAP intake, improved IBS symptoms, and lowered intestinal H₂ production.

Primary Care Management of Chronic Constipation in Asia: The ANMA Chronic Constipation Tool

Chronic constipation (CC) may impact on quality of life. There is substantial patient dissatisfaction; possible reasons are failure to recognize underlying constipation, inappropriate dietary advice and inadequate treatment. The aim of these practical guidelines intended for primary care physicians, and which are based on Asian perspectives, is to provide an approach to CC that is relevant to the existing health-care infrastructure. Physicians should not rely on infrequent bowel movements to diagnose CC as many patients have one or more bowel movement a day. More commonly, patients present with hard stool, straining, incomplete feeling, bloating and other dyspeptic symptoms. Physicians should consider CC in these situations and when patients are found to use laxative containing supplements. In the absence of alarm features physicians may start with a 2-4 week therapeutic trial of available pharmacological agents including osmotic, stimulant and enterokinetic agents. Where safe to do so, physicians should consider regular (as opposed to on demand dosing), combination treatment and continuous treatment for at least 4 weeks. If patients do not achieve satisfactory response, they should be referred to tertiary centers for physiological evaluation of colonic transit and pelvic floor function. Surgical referral is a last resort, which should be considered only after a thorough physiological and psychological evaluation.

Update on the Pathophysiology and Management of Anorectal Disorders

Anorectal disorders are common and present with overlapping symptoms. They include several disorders with both structural and functional dysfunction(s). Because symptoms alone are poor predictors of the underlying pathophysiology, a diagnosis should only be made after evaluating symptoms and physiologic and structural abnormalities. A detailed history, a thorough physical and digital rectal examination and a systematic evaluation with high resolution and/or high definition three-dimensional (3D) anorectal manometry, 3D anal ultrasonography, magnetic resonance defecography and neurophysiology tests are essential to correctly identify these conditions. These physiological and imaging tests play a key role in facilitating a precise diagnosis and in providing a better understanding of the pathophysiology and functional anatomy. In turn, this leads to better and more comprehensive management using medical, behavioral and surgical approaches. For example, patients presenting with difficult defecation may demonstrate dyssynergic defecation and will benefit from biofeedback therapy before considering surgical treatment of coexisting anomalies such as rectoceles or intussusception. Similarly, patients with significant rectal prolapse and pelvic floor dysfunction or patients with complex enteroceles and pelvic organ prolapse may benefit from combined behavioral and surgical approaches, including an open, laparoscopic, transabdominal or transanal, and/or robotic-assisted surgery. Here, we provide an update on the pathophysiology, diagnosis, and management of selected common anorectal disorders.

Prediction of Delayed Colonic Transit Using Bristol Stool Form and Stool Frequency in Eastern Constipated Patients: A Difference From the West

Background/Aims

The correlation between the Bristol stool form scale (BSFS) and colonic transit time (CTT) has been reported in Western populations. Our study aims to study the relationship between BSFS, stool frequency, and CTT in Eastern patients with chronic constipation.

Methods

A total of 144 chronic functional constipation patients underwent colonic transit study by using radio-opaque markers, anorectal manometry, and balloon expulsion test. Stool diary including stool forms and frequency was recorded. Delayed CTT was defined as the retention of more than 20.0% of radio-opaque markers in the colon on day 5.

Results

Twenty-five patients (17.4%) had delayed colonic transit. Mean 5-day BSFS (OR, 0.51; 95% CI, 0.34–0.79; P = 0.021) and stool frequency (OR, 0.60; 95% CI, 0.44–0.83; P = 0.002) were independently associated with delayed CTT by logistic regression analysis. Mean 5-day BSFS (area under the curve [AUC], 0.73; 95% CI, 0.62–0.84; P < 0.001) and stool frequency (AUC, 0.75; 95% CI, 0.63–0.87; P < 0.001) fairly predicted delayed CTT. The optimal mean 5-day BSFS of ≤ 3 provided 68.0% sensitivity, 69.7% specificity, and 69.4% accuracy, and the optimal stool frequency ≤ 2 bowel movements in 5 days provided 64.0% sensitivity, 83.1% specificity, and 84.0% accuracy for predicting delayed CTT.

Conclusions

Both stool form and frequency were significantly associated with delayed CTT. Stool frequency ≤ 2 and BSFS 1–3 rather than BSFS 1–2 that was used in the Westerners could be used as surrogate for delayed CTT in Eastern patients with constipation.

Technique of functional and motility test: how to perform antroduodenal manometry

Antroduodenal manometry is one of the methods to evaluate stomach and duodenal motility. This test is a valuable diagnostic tool for gastrointestinal motility disorders especially small intestinal pseudo-obstruction which is difficult to make definite diagnosis by clinical manifestations or radiologic findings. Manometric findings that have no evidence of mechanical obstruction and suggestive of pseudo-obstruction with neuropathy or myopathy can avoid unnecessary surgery and the treatment can be directly targeted. Moreover, among patients who have clinically suspected small intestinal pseudo-obstruction but with normal manometric findings, the alternative diagnosis including psychiatric disorder or other organic disease should be considered. The application of this test to the patients with functional gastrointestinal symptoms especially to find the association of motor abnormalities to the symptom has less impressive yield. Antroduodenal manometry is now readily available only in some tertiary care centers. The aim of this review is to describe the antroduodenal manometry technique, interpretation and clinical utility.

Gastroesophageal reflux symptoms in typical and atypical GERD: roles of gastroesophageal acid refluxes and esophageal motility

BACKGROUND/AIM

To determine the roles of gastroesophageal acid reflux (GER) and esophageal dysmotility on typical and atypical GERD symptoms.

METHODS

Two hundred thirty-six patients (159 females, age 47 ± 14 years) with typical and atypical GERD symptom(s) for > 3 months underwent standard water perfused esophageal manometry (EM) and 24 h esophageal pH studies during off therapy.

RESULTS

Eighty seven and 93 patients had positive lower esophageal pH tests and abnormal EM, respectively. Patients with positive lower esophageal pH test were significantly older (50 ± 13 vs 45 ± 13 years, P < 0.005) and had higher prevalence of acid regurgitation symptoms than patients with negative test (56/87 vs 72/149, P < 0.05). Patients with positive upper esophageal pH test (n = 67) also had significantly higher prevalence of acid regurgitation symptoms (43/67 vs 74/152, P < 0.05). Prevalence of other upper gastrointestinal and respiratory symptoms were similar between patients with positive and negative upper and lower pH test. Patients with abnormal EM were significantly older (49 ± 14 vs 45 ± 13 years, P < 0.05) and had higher prevalence of chronic cough than patients with normal EM(30/93 vs 26/143, P < 0.05). In patients with positive pH tests, the prevalence of dysphagia, chronic cough, and hoarseness of voice were significantly higher in patients with abnormal than those with normal EM (18/31 vs 18/56, P < 0.05; 12/31 vs 6/56, P < 0.005 and 19/31 vs 18/56, P < 0.01, respectively). Whereas in patients with negative lower pH tests, only the prevalence of heartburn was significantly lower in patients with normal than those with abnormal EM (26/87 vs 30/62, P < 0.05).

CONCLUSIONS

Acid regurgitation but not heartburn was associated with GER. Esophageal dysmotility had no significant effect on acid regurgitation symptom but associated with chronic cough, hoarseness of voice, and dysphagia only in patients with abnormal esophageal acid exposure.

Fecal microbiota transplantation for irritable bowel syndrome: An intervention for the 21st century

Irritable bowel syndrome (IBS) affects about 12% of the global population. Although IBS does not develop into a serious disease or increase mortality, it results in a considerable reduction in the quality of life. The etiology of IBS is not known, but the intestinal microbiota appears to play a pivotal role in its pathophysiology. There is no effective treatment for IBS, and so the applied treatments clinically focus on symptom relief. Fecal microbiota transplantation (FMT), an old Chinese treatment, has been applied to IBS patients in seven randomized controlled trials (RCTs). Positive effects on IBS symptoms in various degrees were obtained in four of these RCTs, while there was no effect in the remaining three. Across the seven RCTs there were marked differences in the selection processes for the donor and treated patients, the transplant dose, the route of administration, and the methods used to measure how the patients responded to FMT. The present frontier discusses these differences and proposes: (1) criteria for selecting an effective donor (superdonor); (2) selection criteria for patients that are suitable for FMT; (3) the optimal FMT dose; and (4) the route of transplant administration. FMT appears to be safe, with only mild, self-limiting side effects of abdominal pain, cramping, tenderness, diarrhea, and constipation. Although it is early to speculate about the mechanisms underlying the effects of FMT, the available data suggest that changes in the intestinal bacteria accompanied by changes in fermentation patterns and fermentation products (specifically short-chain fatty acids) play an important role in improving the IBS symptoms seen after FMT. FMT appears to be a promising treatment for IBS, but further studies are needed before it can be applied in everyday clinical practice.

Randomised clinical trial: linaclotide vs placebo-a study of bi-directional gut and brain axis

BACKGROUND

Linaclotide, a guanylate cyclase C agonist relieves irritable bowel syndrome with predominant constipation (IBS-C) symptoms, but how it improves pain in humans is unknown.

AIMS

To investigate the effects of linaclotide and placebo on the afferent and efferent gut-brain-gut signalling in IBS-C patients, in a randomised clinical trial.

METHODS

Patients with IBS-C (Rome III) and rectal hypersensitivity were randomised (2:1) to receive linaclotide (290 µg) or placebo for 10 weeks and undergo bi-directional gut and brain axis assessment using anorectal electrical stimulations and transcranial/transspinal-anorectal magnetic stimulations. Rectal sensations were examined by balloon distention. Assessments included abdominal pain, bowel symptoms and quality of life (QOL) scores. Primary outcomes were latencies of recto-cortical and cortico-rectal evoked potentials.

RESULTS

Thirty-nine patients participated; 26 received linaclotide and 13 received placebo. Rectal cortical evoked potentials latencies (milliseconds) were significantly prolonged with linaclotide compared to baseline (P1:Δ 19 ± 6, P < 0.005; N1:Δ 20 ± 7, P < 0.02) but not with placebo (P1:Δ 3 ± 5; N1:Δ 4.7 ± 5,P = 0.3) or between groups. The efferent cortico-anorectal and spino-anorectal latencies were unchanged. The maximum tolerable rectal volume (cc) increased significantly with linaclotide compared to baseline (P < 0.001) and placebo (Δ 29 ± 10 vs 4 ± 20, (P < 0.03). Abdominal pain decreased (P < 0.001) with linaclotide but not between groups. Complete spontaneous bowel movement frequency increased (P < 0.001), and IBS-QOL scores improved (P = 0.01) with linaclotide compared to baseline and placebo. There was no difference in overall responders between linaclotide and placebo (54% vs 23%, P = 0.13).

CONCLUSIONS

Linaclotide prolongs afferent gut-brain signalling from baseline but both afferent and efferent signalling were unaffected compared to placebo. Linaclotide significantly improves rectal hypersensitivity, IBS-C symptoms and QOL compared to placebo. These mechanisms may explain the effects of linaclotide on pain relief in IBS-C patients. ClinicalTrials.Gov: Registered at Clinical trials.gov no NCT02078323.

Identification of a novel gut microbiota signature associated with colorectal cancer in Thai population

Colorectal cancer (CRC) is the third most common cancer worldwide. Dysbiosis of human gut microbiota has been linked to sporadic CRC. This study aimed to compare the gut microbiota profiles of 80 Thai volunteers over 50 years of age among 25 CRC patients, 33 patients with adenomatous polyp, and 22 healthy controls. The 16S rRNA sequencing was utilized to characterize the gut microbiome in both mucosal tissue and stool samples. The results revealed that the luminal microbiota incompletely represented the intestinal bacteria at the mucus layer. The mucosal microbiota in beta diversity differed significantly among the three groups. The stepwise increase of Bacteroides and Parabacteroides according to the adenomas-carcinomas sequence was found. Moreover, linear discriminant analysis effect size showed a higher level of Erysipelatoclostridium ramosum (ER), an opportunistic pathogen in the immunocompromised host, in both sample types of CRC patients. These findings indicated that the imbalance of intestinal microorganisms might involve in CRC tumorigenesis. Additionally, absolute quantitation of bacterial burden by quantitative real-time PCR (qPCR) confirmed the increasing ER levels in both sample types of cancer cases. Using ER as a stool-based biomarker for CRC detection by qPCR could predict CRC in stool samples with a specificity of 72.7% and a sensitivity of 64.7%. These results suggested ER might be a potential noninvasive marker for CRC screening development. However, a larger sample size is required to validate this candidate biomarker in diagnosing CRC.

Chromogranin A cell density in the large intestine of Asian and European patients with irritable bowel syndrome

OBJECTIVE

Patients with irritable bowel syndrome (IBS) in Asia show distinctive differences from those in the western world. The gastrointestinal endocrine cells appear to play an important role in the pathophysiology of IBS. The present study aimed at studying the density of chromogranin A (CgA) cells in the large intestine of Thai and Norwegian IBS patients.

METHODS

Thirty Thai IBS patients and 20 control subjects, and 47 Norwegian IBS patients and 20 control subjects were included. A standard colonoscopy was performed in both the patients and controls, and biopsy samples were taken from the colon and the rectum. The biopsy samples were stained with hematoxylin-eosin and immunostained for CgA. The density of CgA cells was determined by computerized image analysis.

RESULTS

In the colon and rectum, the CgA cell densities were far higher in both IBS and healthy Thai subjects than in Norwegians. The colonic CgA cell density was lower in Norwegian IBS patients than in controls, but did not differ between Thai IBS patients and controls. In the rectum, the CgA cell densities in both Thai and Norwegian patients did not differ from those of controls.

CONCLUSIONS

The higher densities of CgA cells in Thai subjects than Norwegians may be explained by a higher exposure to infections at childhood and the development of a broad immune tolerance, by differences in the intestinal microbiota, and/or differing diet habits. The normal CgA cell density in Thai IBS patients in contrast to that of Norwegians may be due to differences in pathophysiology.

Effect of Rice, Wheat, and Mung Bean Ingestion on Intestinal Gas Production and Postprandial Gastrointestinal Symptoms in Non-Constipation Irritable Bowel Syndrome Patients

The aim of this study is to evaluate the effect of rice, mung bean, and wheat noodle ingestion on intestinal gas production and postprandial gastrointestinal (GI) symptoms in non-constipation irritable bowel syndrome (IBS) patients. Methods: Twenty patients (13 F, 46 ± 11 y) underwent 8 h breath test studies and GI symptom evaluations after standard rice, wheat, or mung bean noodle meals at 8:00 a.m. in a randomized crossover study with a 1-week washout period. The same meal was ingested at 12:00 p.m. Results: The H₂ and CH₄ concentration in the breath samples were similar at baseline (rice:wheat:mung bean, H₂ = 3.6 ± 0.5:4.1 ± 0.5:4.0 ± 0.7 ppm, CH₄ = 1.3 ± 0.3:2.1 ± 0.4:1.9 ± 0.4 ppm, p > 0.05). Beginning at the fifth hour after breakfast, H₂ and CH₄ concentrations significantly increased after wheat compared to rice and mung bean (8 h AUC H₂ = 4120 ± 2622:2267 ± 1780:2356 ± 1722, AUC CH₄ = 1617 ± 1127:946 ± 664:943 ± 584 ppm-min, respectively) (p < 0.05). Bloating and satiety scores significantly increased after wheat compared to rice (p < 0.05), and increased but did not reach statistical significance compared to mung bean (p > 0.05). A higher bloating score after wheat compared to rice and mung bean was observed clearly after lunch but not after breakfast. Conclusion: Wheat ingestion produced more intestinal gas and more bloating and satiety scores compared to rice and mung bean, especially after lunch. This provides insight into the role of intestinal gas in the development of bloating symptoms in IBS.

The Therapeutic and Diagnostic Value of 2-week High Dose Proton Pump Inhibitor Treatment in Overlapping Non-erosive Gastroesophageal Reflux Disease and Functional Dyspepsia Patients

Background/Aims

To evaluate the value of a 2-week high dose proton pump inhibitor (PPI) treatment on patients with overlapping non-erosive gastroesophageal reflux disease (NERD) and functional dyspepsia (FD).

Methods

Sixty overlapping NERD and FD patients with symptom onset > 3 months prior underwent 24-hour esophageal pH monitoring studies. All patients received rabeprazole 20 mg b.i.d. for 2 weeks. The reflux and dyspeptic symptoms were evaluated using a symptom questionnaire with 4-point Likert scales before and at the end of treatment. A positive PPI test was defined as score improvement in ≥ 50% from the baseline in the typical reflux symptoms.

Results

The prevalence of each reflux and dyspeptic symptom did not differ significantly between patients with positive and negative pH tests. After the PPI treatment, epigastric burning, acid regurgitation, heartburn, nausea, vomiting and chest discomfort scores were significantly improved compared to pretreatment values (P < 0.05), whereas postprandial abdominal fullness, early satiation, belching and food regurgitation were not. The proportion of patients who responded to the PPI treatment did not differ significantly between patients with positive and negative pH tests. The sensitivity, specificity, PPV, NPV and accuracy of 2-week high dose rabeprazole treatment for diagnosing gastroesophageal reflux disease were 47%, 38%, 50%, 35% and 43%, respectively.

Conclusions

The two-week high dose PPI treatment was not effective for early satiation, postprandial abdominal fullness, regurgitation or belching symptoms in patients with overlapping NERD and FD. Acid exposure in the distal esophagus could not predict the response of symptoms to PPI. In addition, the 2-week PPI test provided limited value for gastroesophageal reflux disease diagnosis in patients with overlapping NERD and FD.

Fecal microbiota transplantation in irritable bowel syndrome: A meta-analysis of randomized controlled trials

Introduction

Fecal microbiota transplantation (FMT) has been proposed as a potential treatment for irritable bowel syndrome (IBS); however, the consensus regarding its efficacy and safety is limited.

Materials and Methods

We performed a systematic search of the literature using PubMed, EMBASE, Ovid MEDLINE, and Cochrane. Meta-analyses were conducted in relative risk (RR) or standard mean difference (SMD) using 95% confidence intervals (CI). Cochrane risk-of-bias 2 tool (RoB2) was employed to evaluate the study quality.

Result

Of 2,589 potential records, 7 studies with 9 cohorts involving 505 participants were included. Meta-analyses showed no significant difference in the short-term (12 weeks) and long-term (12 months) global improvement of IBS symptoms of FMT vs. placebo (RR 0.63, 95% CI 0.39-1.00 and RR 0.88, 95% CI 0.53-1.45, respectively). There were statistically significant differences of short-term IBS-SSS improvement (SMD -0.58, 95% CI -1.09 to -0.88) and short-term IBS-QoL improvement (SMD 0.67, 95% CI 0.43-0.91). Eight from 9 studies (88.9%) had a low risk of bias. The subgroup analysis revealed the short-term global symptoms improvement in studies with low-risk of bias (RR 0.53, 95% CI 0.35-0.81), studies with well-defined donors (RR 0.31, 95% CI 0.14-0.72), and studies with FMT using colonoscopy (RR 0.66, 95% CI 0.47-0.92). Major FMT adverse events are transient and rapidly self-limiting.

Conclusion

FMT significantly improved IBS-SSS and IBS-QoL in the short-term period in IBS patients. However, global symptom improvement showed no significance. Well-defined donors and appropriate fecal administration routes appear to be important factors for the successful outcomes of FMT in IBS.

Systematic review registration

[www.crd.york.ac.uk/prospero], identifier [CRD42021246101].

The Practice of Gastrointestinal Motility Laboratory During COVID-19 Pandemic: Position Statements of the Asian Neurogastroenterology and Motility Association (ANMA-GML-COVID-19 Position Statements)

During the Coronavirus Disease 2019 (COVID-19) pandemic, practices of gastrointestinal procedures within the digestive tract require special precautions due to the risk of contraction of severe acute respiratoy syndrome coronavirus-2 (SARS-CoV-2) infection. Many procedures in the gastrointestinal motility laboratory may be considered moderate to high-risk for viral transmission. Healthcare staff working in gastrointestinal motility laboratories are frequently exposed to splashes, air droplets, mucus, or saliva during the procedures. Moreover, some are aerosol-generating and thus have a high risk of viral transmission. There are multiple guidelines on the practices of gastrointestinal endoscopy during this pandemic. However, such guidelines are still lacking and urgently needed for the practice of gastrointestinal motility laboratories. Hence, the Asian Neurogastroenterology and Motility Association had organized a group of gastrointestinal motility experts and infectious disease specialists to produce a position statement paper based-on current available evidence and consensus opinion with aims to provide a clear guidance on the practices of gastrointestinal motility laboratories during the COVID-19 pandemic. This guideline covers a wide range of topics on gastrointestinal motility activities from scheduling a motility test, the precautions at different steps of the procedure to disinfection for the safety and well-being of the patients and the healthcare workers. These practices may vary in different countries depending on the stages of the pandemic, local or institutional policy, and the availability of healthcare resources. This guideline is useful when the transmission rate of SARS-CoV-2 is high. It may change rapidly depending on the situation of the epidemic and when new evidence becomes available.

Randomized controlled trial of home biofeedback therapy versus office biofeedback therapy for fecal incontinence

BACKGROUND

Biofeedback therapy is useful for treatment of fecal incontinence (FI), but is not widely available and labor intensive. We investigated if home biofeedback therapy (HBT) is non-inferior to office biofeedback therapy (OBT).

METHODS

Patients with FI (≥1 episode/week) were randomized to HBT or OBT for 6 weeks. HBT was performed daily using novel device that provided resistance training and electrical stimulation with voice-guided instructions. OBT consisted of six weekly sessions. Both methods involved anal strength, endurance, and coordination training. Primary outcome was change in weekly FI episodes. FI improvement was assessed with stool diaries, validated instruments (FISI, FISS, and ICIQ-B), and anorectal manometry using intention-to-treat analysis.

KEY RESULTS

Thirty (F/M = 26/4) FI patients (20 in HBT, 10 in OBT) participated. Weekly FI episodes decreased significantly after HBT (Δ ± 95% confidence interval: 4.7 ± 1.8, compared with baseline, p = 0.003) and OBT (3.7 ± 1.6, p = 0.0003) and HBT was non-inferior to OBT (p = 0.2). The FISI and FISS scores improved significantly in HBT group (p < 0.02). Bowel pattern, bowel control, and quality of life (QOL) domains (ICIQ-B) improved significantly in HBT arm (p < 0.023). Resting and maximum squeeze sphincter pressures significantly improved in both HBT and OBT groups and sustained squeeze pressure in HBT, without group differences.

CONCLUSIONS & INFERENCES

Home biofeedback therapy is non-inferior to OBT for FI treatment. Home biofeedback is safe, effective, improves QOL, and through increased access could facilitate improved management of FI.

Knowledge, Attitude, and Practice Survey of Gastroparesis in Asia by Asian Neurogastroenterology and Motility Association

Background/Aims

Gastroparesis is identified as a subject that is understudied in Asia. The scientific committee of the Asian Neurogastroenterology and Motility Association performed a Knowledge, Attitude, and Practices survey on gastroparesis among doctors in Asia.

Methods

The questionnaire was created and developed through a literature review of current gastroparesis works of literature by the scientific committee of Asian Neurogastroenterology and Motility Association.

Results

A total of 490 doctors from across Asia (including Bangladesh, China, Hong Kong, Indonesia, Japan, Malaysia, Myanmar, the Philippines, Singapore, South Korea, Taiwan, Thailand, and Vietnam) participated in the survey. Gastroparesis is a significant gastrointestinal condition. However, a substantial proportion of respondents was unable to give the correct definition and accurate diagnostic test. The main reason for lack of interest in diagnosing gastroparesis was "the lack of reliable diagnostic tests" (46.8%) or "a lack of effective treatment" (41.5%). Only 41.7% of respondents had access to gastric emptying scintigraphy. Most doctors had never diagnosed gastroparesis at all (25.2%) or diagnosed fewer than 5 patients a year (52.1%).

Conclusions

Gastroparesis can be challenging to diagnose due to the lack of instrument, standardized method, and paucity of research data on normative value, risk factors, and treatment studies in Asian patients. Future strategies should concentrate on how to disseminate the latest knowledge of gastroparesis in Asia. In particular, there is an urgent need to estimate the magnitude of the problems in high risk and idiopathic patients as well as a standardized diagnostic procedure in Asia.

Enteroendocrine, Musashi 1 and neurogenin 3 cells in the large intestine of Thai and Norwegian patients with irritable bowel syndrome

OBJECTIVES

The prevalence, gender distribution and clinical presentation of IBS differ between Asian and Western countries. This study aimed at studying and comparing enteroendocrine, Musashi 1 (Msi 1) and neurogenin 3 (neurog 3) cells in Thai and Norwegian IBS patients.

MATERIAL AND METHODS

Thirty Thai and 61 Norwegian IBS patients as well as 20 Thai and 24 Norwegian controls were included. Biopsy samples were taken from each of the sigmoid colon and the rectum during a standard colonoscopy. The samples were immunostained for serotonin, peptide YY, oxyntomodulin, pancreatic polypeptide, somatostatin, Msi 1 and neurog 3. The densities of immunoreactive cells were determined with computerized image analysis.

RESULTS

The densities of several enteroendocrine cell types were altered in both the colon and rectum of both Thai and Norwegian IBS patients. Some of these changes were similar in Thai and Norwegian IBS patients, while others differed.

CONCLUSIONS

The findings of abnormal densities of the enteroendocrine cells in Thai patients support the notion that enteroendocrine cells are involved in the pathophysiology of IBS. The present observations highlight that IBS differs in Asian and Western countries, and show that the changes in large-intestine enteroendocrine cells in Thai and Norwegian IBS patients might be caused by different mechanisms.

Treatment outcomes and validation of the stopping rule for response to peginterferon in chronic hepatitis B: A Thai nationwide cohort study

BACKGROUND AND AIMS

Peginterferon has demonstrated effectiveness in clinical trials in patients with chronic hepatitis B (CHB). However, its efficacy in real-life settings remains unclear. We investigated the efficacy of peginterferon for CHB and validated the performance of previously identified response predictors in clinical practice.

METHODS

We analyzed prospectively collected data from a Thai nationwide cohort of CHB patients treated with peginterferon alfa-2a (180 µg/week, 48 weeks).

RESULTS

Among a total of 233 patients, mostly with genotype B or C, sustained response was observed in 23% of 135 hepatitis B e antigen (HBeAg)-positive patients (HBeAg seroconversion with hepatitis B virus [HBV] DNA < 2000 IU/mL) and 42% of 98 HBeAg-negative patients (HBV DNA < 2000 IU/mL with aminotransferase normalization) at 24 weeks after treatment. Age, sex, presence of cirrhosis, genotype, and pretreatment levels of aminotransferase, HBV DNA, and hepatitis B surface antigen (HBsAg) were not identified as significant predictors of sustained response. In HBeAg-positive patients, HBsAg > 20 000 IU/mL at week 12 provided a good stopping rule, with a negative predictive value of 96%. In HBeAg-negative patients, the performance of 12-week stopping rules of no decline in HBsAg with a < 2log₁₀ decline in HBV DNA and a < 10% log₁₀ decline in HBsAg showed modest negative predictive values of 80% and 66%, respectively, for achieving sustained response.

CONCLUSION

Outcomes in CHB patients treated with peginterferon in a clinical setting are similar to those demonstrated in clinical trials. Application of the early stopping rule based on HBsAg quantification may allow individualization of therapy, particularly in HBeAg-positive patients.

Thailand guideline 2020 for medical management of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is one of the most prevalent and bothersome functional gastrointestinal disorders worldwide, including in Thailand. After a decade of the first Thailand GERD guideline, physician and gastroenterologist encountered substantially increase of patients with GERD. Many of them are complicated case and refractory to standard treatment. Concurrently, the evolution of clinical characteristics as well as the progression of investigations and treatment have developed and changed tremendously. As a member of Association of Southeast Asian Nations, which are developing countries, we considered that the counterbalance between advancement and sufficient economy is essential in taking care of patients with GERD. We gather physicians from university hospitals, as well as internist and general practitioners who served in rural area, to make a consensus in this updated version of GERD guideline focusing in medical management of GERD. This clinical practice guideline was constructed adhering with standard procedure. We categorized the guideline in to four parts including definition, investigation, treatment, and long-term follow up. We anticipate that this guideline would improve physicians' proficiency and help direct readers to choose investigations and treatments in patients with GERD wisely. Moreover, we wish that this guideline would be applicable in countries with limited resources as well.

The role of diet in the pathophysiology and management of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a chronic gastrointestinal (GI) disorder that reportedly affects 5% to 20% of the world population. The etiology of IBS is not completely understood, but diet appears to play an important role in its pathophysiology. Asian diets differ considerably from those in Western countries, which might explain differences in the prevalence, sex, and clinical presentation seen between patients with IBS in Asian and Western countries. Dietary regimes such as a low-fermentable oligo-, di-, monosaccharides, and polyols (FODMAP) diet and the modified National Institute for Health and Care Excellence (NICE) diet improve both symptoms and the quality of life in a considerable proportion of IBS patients. It has been speculated that diet is a prebiotic for the intestinal microbiota and favors the growth of certain bacteria. These bacteria ferment the dietary components, and the products of fermentation act upon intestinal stem cells to influence their differentiation into enteroendocrine cells. The resulting low density of enteroendocrine cells accompanied by low levels of certain hormones gives rise to intestinal dysmotility, visceral hypersensitivity, and abnormal secretion. This hypothesis is supported by the finding that changing to a low-FODMAP diet restores the density of GI cells to the levels in healthy subjects. These changes in gut endocrine cells caused by low-FODMAP diet are also accompanied by improvements in symptoms and the quality of life.

Detection of reflux-symptom association in children with esophageal atresia by video-pH-impedance study

BACKGROUND

Children with esophageal atresia (EA) have risk of gastroesophageal reflux disease (GERD), suggesting reflux monitoring for prompt management.

AIM

To evaluate GERD in children with EA and specific symptom association from combined Video with Multichannel Intraluminal Impedance and pH (MII-pH) study.

METHODS

Children diagnosed with EA with suspected GERD and followed up at King Chulalongkorn Memorial Hospital between January 2000 and December 2018 were prospectively studied. All underwent esophagogastroduodenoscopy with esophageal biopsy and Video MII-pH study on the same day. Symptoms of GERD which included both esophageal and extra-esophageal symptom were recorded from video monitoring and abnormal reflux from MII-pH study based on the statement from the European Paediatric Impedance Group. Prevalence of GERD was also reported by using histopathology as a gold standard. Endoscopic appearance was recorded using Los Angeles Classification and esophagitis severity was graded using Esohisto criteria.

RESULTS

Fifteen children were recruited with age of 3.1 (2.2, 9.8) years (40%, male) and the common type was C (93.3%). The symptoms recorded were cough (75.2%), vomiting (15.2%), irritability or unexplained crying (7.6%) and dysphagia (1.9%) with the symptom-reflux association of 45.7%, 89%, 71% and 0%, respectively. There were abnormal endoscopic appearance in 52.9%, esophagitis in 64.7% and high reflux score in 47.1%. Video MII-pH study has high diagnostic value with the sensitivity, specificity and accuracy of 72.7%, 100% and 82.4%, respectively.

CONCLUSION

Prevalence of GERD in children with EA was high. Video MII-pH study to detect GERD in children with EA had high diagnostic value with the trend of specific symptom association.