Myelodysplastic Syndrome: Diagnosis and Screening.

Myelodysplastic syndromes (MDS) are heterogeneous groups of clonal myeloid disorders characterized by unexplained persistent peripheral blood (PB) cytopenia(s) of one or more of the hematopoietic lineages, or bone marrow (BM) morphologic dysplasia in hematopoietic cells, recurrent genetic abnormalities, and an increased risk of progression to acute myeloid leukemia (AML). In the past several years, diagnostic, prognostic, and therapeutic approaches have substantially improved with the development of Next Generation Sequencing (NGS) diagnostic testing and new medications. However, there is no single diagnostic parameter specific for MDS, and correlations with clinical information, and laboratory test findings are needed to reach the diagnosis.

Clinical trial: seven-day vonoprazan- versus 14-day proton pump inhibitor-based triple therapy for first-line Helicobacter pylori eradication.

BACKGROUND: One-week triple therapy with vonoprazan is endorsed by Japanese guidelines as an alternative to proton pump inhibitor (PPI)-based triple therapy for first-line Helicobacter pylori eradication. This contrasts with Western guidelines recommending 2-week PPI-based triple therapy. AIM: To verify the non-inferiority of 1-week vonoprazan-based triple therapy versus 2-week PPI-based triple therapy as first-line H. pylori eradication in a multiracial Asian cohort. METHODS: Randomised controlled trial of treatment-naïve patients with H. pylori infection assigned 1:1 to either 7 days amoxicillin 1 g + clarithromycin 500 mg + vonoprazan 20 mg twice per day or 14 days amoxicillin 1 g + clarithromycin 500 mg + omeprazole OR esomeprazole OR rabeprazole 20 mg twice/day. Subjects were randomly assigned to each PPI 1:1:1 Demographics, H. pylori resistance, CYP 2C19 genotype, eradication success and safety profiles were compared between groups. RESULTS: Between June 2019 and June 2021, 252 of 1097 subjects screened were randomised. 244 (age [SD] 51.7 [14.6]) received vonoprazan- (n = 119) or PPI-based (n = 125) triple therapy. Eradication rates by intention-to-treat analysis were 87.4% (vonoprazan-based triple therapy) versus 88.0% (PPI-based triple therapy. By per protocol analysis: 96.3% (vonoprazan-based triple therapy) versus 94.0% (PPI-based triple therapy). Clarithromycin resistance predicted treatment failure on multivariate analysis: RR 11.4; 95% CI [1.4-96.3], p = 0.025. No significant differences in CYP 2C19 genotypes or adverse events occurred between groups. CONCLUSION: One-week vonoprazan-based triple therapy achieved comparable efficacy to 2-week PPI-based triple therapy and was well tolerated.

Evaluation of a six-probe cocktail (caffeine, tolbutamide, omeprazole, dextromethorphan, midazolam, and digoxin) approach to estimate hepatic drug detoxification capability and dosage requirements after a single oral dosing in healthy Chinese volunteers.

The primary objectives of this study were to investigate the suitability of a 6-probe cocktail (caffeine, tolbutamide, omeprazole, dextromethorphan, midazolam, and digoxin) to be used as a tool for assessing the activity of drug metabolizing enzymes and transporters, and examine differences in the way drugs are handled among groups with different genetic regulation of these processes. This was a single-center, open-label, phase I clinical study involving 20 young, healthy Chinese volunteers (equal gender distribution). The subjects were administered a single, oral dose of the 6-probe cocktail and serum samples were collected to assess the disposition of the different probe substrates and produced metabolites. The serum samples were analyzed using ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry technology. The DNA samples were subjected to whole exome sequencing. Nineteen healthy volunteers completed the study. The 6-probe cocktail was safe and well-tolerated by all the subjects. The parent substrates and metabolites-caffeine (paraxanthine), dextromethorphan (dextrorphan), digoxin, midazolam (1-hydroxy-midazolam), omeprazole (5-hydroxy-omeprazole), and tolbutamide (4-hydroxy-tolbutamide)-were within the detectable window. Genetic variations known to alter drug metabolism (CYP2D6*10, CYP2C19*2, CYP2C19*3, and CYP2C9*3) were identified and generally correlated with phenotypic status. The 6-probe cocktail appeared to be suitable for assessing drug metabolizing activities. This, in conjunction with individual genetics, will pave the way for the implementation of personalized medicine in clinical practice. This will hopefully improve efficacy and reduce the incidence of adverse drug reactions.

The present and future of gastroenterology and hepatology: an international SWOT analysis (the GASTROSWOT project).

GASTROSWOT is a strategic analysis of the current and projected states of the different subspecialties in gastroenterology that aims to provide guidance for research, clinical, and financial planning in gastroenterology. We executed a consensus-based international strengths, weaknesses, opportunities, and threats (SWOT) analysis. Four general coordinators, six field coordinators, and 12 experts participated in the study. SWOTs were provided for the following fields: neurogastroenterology, functional gastrointestinal disorders, and upper gastrointestinal diseases; inflammatory bowel disease; pancreatology and biliary diseases; endoscopy; gastrointestinal oncology; and hepatology. The GASTROSWOT analysis highlights the following in the current state of the field of gastroenterology: the incidence and complexity of several gastrointestinal diseases, including malignancies, are increasing; the COVID-19 pandemic has affected patient care on several levels; and with the advent of technical innovations in gastroenterology, a well trained workforce and strategic planning are required to optimise health-care utilisation. The analysis calls attention to the following in the future of gastroenterology: artificial intelligence and the use of big data will speed up discovery and smarter health-care provision in the field; the growth and diversification of gastroenterological specialties will improve specialised care for patients, but could promote fragmentation of care and health system inefficiencies; and furthermore, thoughtful planning is needed to reach an effective balance between the need for subspecialists and the value of general gastroenterology services.

Clinical audit of current Helicobacter pylori treatment outcomes in Singapore.

Introduction: H. pylori eradication reduces the risk of gastric malignancies and peptic ulcer disease. First-line therapies include 14-day PAC (proton pump inhibitor [PPI], amoxicillin, clarithromycin) and PBMT (PPI, bismuth, metronidazole, tetracycline). Second-line therapies include 14-day PBMT and PAL (PPI, amoxicillin, levofloxacin). This clinical audit examined current treatment outcomes in Singapore. Methods: Clinical data of H. pylori-positive patientswho underwent empirical first- and second-line eradication therapies from 1 January 2017 to 31 December 2018 were reviewed. Treatment success was determined by 13C urea breath test performed at least 4 weeks after treatment and 2 weeks off PPI. Results: A total of 963 patients (862 PAC, 36 PMC [PPI, metronidazole, clarithromycin], 18 PBMT, 13 PBAC [PAC with bismuth], 34 others) and 98 patients (62 PMBT, 15 PAL, 21 others) received first-and second-line therapies respectively. A 14-day treatment duration was appropriately prescribed for first- and second-line therapies in 65.2% and 82.7% of patients, respectively. First-line treatment success rates were noted for PAC (seven-day: 76.9%, ten-day: 88.3%, 14-day: 92.0%), PMC (seven-day: 0, ten-day: 75.0%, 14-day: 69.8%), PBMT (ten-day: 100%, 14-day: 87.5%) and PBAC (14-day: 100%). 14-day treatment was superior to seven-day treatment (90.8% vs. 71.4%; P = 0.028). PAC was superior to PMC (P < 0.001) but similar to PBMT (P = 0.518) and PBAC (P = 0.288) in 14-day therapies. 14-day second-line PAL and PBMT had similar efficacy (90.9% vs. 82.4%; P = 0.674). Conclusion: First-line empirical treatment using PAC, PBMT and PBAC for 14 days had similar efficacy. Success rates for second-line PBMT and PAL were similar.

Redundancy in the International Anorectal Physiology Working Group Manometry Protocol: A Diagnostic Accuracy Study in Fecal Incontinence.

BACKGROUND: Anorectal manometry (ARM) is essential for identifying sphincteric dysfunction. The International Anorectal Physiology Working Group (IAPWG) protocol and London Classification provide a standardized format for performing and interpreting ARM. However, there is scant evidence to support timing and number of constituent maneuvers. AIMS: To assess the impact of protocol modification on diagnostic accuracy in patients with fecal incontinence. METHODS: Retrospective analysis of high-resolution ARM recordings from consecutive patients based on the current IAPWG protocol and modifications thereof: (1) baseline rest period (60 vs. 30 vs. 10 s); (2) number of abnormal short squeezes (SS) out of 3 (SS1/SS2/SS3) based on maximal incremental squeeze pressures over 5 s; (3) resting anal pressures (reflecting recovery) at 25-30 versus 15-20 s after SS1. RESULTS: One hundred patients (86 F, median age 55 [IQR: 39-65]; median St. Mark's incontinence score 14 [10-17]) were studied. 26% and 8% had anal hypotonia and hypertonia, respectively. Compared with 60-s resting pressure, measurements had perfect correlation (κ = 1.0) over 30 s, and substantial correlation (κ = 0.85) over 10 s. After SS1, SS2, and SS3, 43%, 49%, and 46% had anal hypocontractility, respectively. Correlation was substantial between SS1 and SS2 (κ = 0.799) and almost perfect between SS2 and SS3 (κ = 0.9). Compared to resting pressure of 5 s before SS1, pressure recordings at 25-30 and 15-20 s after SS1 were significantly correlated. CONCLUSIONS: A 30-s resting anal pressure, analysis of 2 short-squeezes with a 20-s between-maneuver recovery optimizes study duration without compromising diagnostic accuracy. These findings indicate the IAPWG protocol has redundancy.

Guidance on performance and reporting of high-resolution oesophageal manometry and ambulatory pH monitoring in Singapore.

INTRODUCTION: We aimed to provide a practical and evidence-based guide on the indications, performance and reporting of high-resolution oesophageal manometry (HRM) and ambulatory pH monitoring (PHM) in adult patients in Singapore. METHODS: The guideline committee comprised local gastroenterologists from public and private sectors with particular expertise in aspects of HRM and PHM, and it was tasked to produce evidence-based statements on the indications, performance and reporting of these tests. Each committee member performed literature searches to retrieve relevant articles within the context of domains to which they were assigned. RESULTS: Twelve recommendation statements were created and summarised. CONCLUSION: Standardising key aspects of HRM and PHM is imperative to ensure the delivery of high-quality care. We reported the development of recommendations for the performance and interpretation of HRM and ambulatory reflux monitoring in Singapore.

Helicobacter pylori Treatment Strategies in Singapore.

The management of Helicobacter pylori infection in Singapore remains a clinical challenge. Similar to other regions, there has been an increase in antibiotic resistance rates through the years. Nonetheless, over the past two decades, clarithromycin-based triple therapy has continued to be used as the first line treatment option, with an eradication rate exceeding 90%, although the accepted treatment duration must now be lengthened from 1 to 2 weeks to maintain efficacy. Concomitant and sequential therapies did not demonstrate superiority over standard triple therapy. Current empiric second line treatment utilizes either bismuth-based quadruple therapy or levofloxacin-based triple therapy, but outcomes remain less than ideal. Identifying options to further improve treatment success rates is challenging. Strategies being considered include the use of potent acid suppressants, such as vonoprazan, and H. pylori culture and antibiotic susceptibility testing-guided therapy.

Altered anal slow-wave pressure activity in low anterior resection syndrome: short case series in two independent specialist centres provide new mechanistic insights.

AIM: Conventional parameters (anal resting and squeeze pressures) measured with anorectal manometry (ARM) fail to identify anal sphincter dysfunction in many patients with low anterior resection syndrome (LARS). We aimed to assess whether there are differences in anal canal slow-wave pressure activity in LARS patients and healthy individuals. METHOD: High-resolution ARM (HR-ARM) traces of 21 consecutive male LARS patients referred to the Royal London Hospital, UK (n = 12) and Aarhus University Hospital, Denmark (n = 9) were compared with HR-ARM data from 37 healthy men. RESULTS: Qualitatively (by visual inspection of HR-ARM recordings), the frequency of slow-wave pressure activity was strikingly different in 11/21 (52.4%) LARS patients from that observed in all the healthy individuals. Quantitative analysis showed that peaks of the mean spectrum in these 11 LARS patients occurred at approximately 6-7 cycles per minute (cpm), without activity at higher frequencies. An equivalent pattern was found in only 2/37 (5.4%) healthy individuals (P < 0.0001). Peaks of the mean spectrum in healthy individuals were concentrated at 16 cpm and 3-4 cpm. CONCLUSION: Over half of the male LARS patients studied had altered anal slow-wave pressure activity based on analysis of HR-ARM recordings. Further studies could investigate the relative contributions of sex, human baseline variance and neoadjuvant/surgical therapies on anal slow waves, and correlate the presence of abnormal activity with symptom severity.

Diagnosis of gastroesophageal reflux: an update on current and emerging modalities.

Gastroesophageal reflux disease (GERD) is a common condition characterized by troublesome symptoms or esophageal mucosal lesions attributed to excessive esophageal acid exposure. Various pathophysiological mechanisms account for GERD, including impaired esophageal peristalsis and anatomical or physiological defects at the esophagogastric junction (EGJ). Endoscopy identifies GERD complications and detects potential alternative diagnoses. However, if symptoms persist despite proton pump inhibitor therapy, functional esophageal tests are useful to characterize reflux burden and define the symptom association profile. Ambulatory pH or pH-impedance monitoring measures the 24-h acid exposure time, which remains the most reproducible reflux metric and predicts response to antireflux therapy. Apart from identifying peristaltic dysfunction, esophageal high-resolution manometry defines the morphology and contractile vigor (EGJ-CI) of the EGJ. Novel metrics obtained from pH-impedance monitoring include the postreflux swallow-induced peristaltic wave index and mean nocturnal baseline impedance, which augment the diagnostic value of pH-impedance testing. Mucosal impedance can also be recorded using a probe inserted through a gastroscope, or a novel balloon catheter with arrays of impedance electrodes inserted following sedated endoscopy. The latest developments in functional esophageal tests define the GERD phenotype based on pathogenesis, reflux exposure, structural or motility disorders, and symptom burden, facilitating appropriate treatment.

Prospective serial diagnostic study: the effects of position and provocative tests on the diagnosis of oesophageal motility disorders by high-resolution manometry.

BACKGROUND: Standard high-resolution manometry (HRM) protocols are based on 10 single water swallows acquired in the supine position. AIMS: To assess the impact of position, rapid drink challenge and solid test meal on the diagnosis of oesophageal motility disorders. METHODS: Seventy-two healthy volunteers (20-76 years) and 366 consecutive patients (18-90 years) completed HRM with 10 single water swallows in the supine and upright positions. Rapid drink challenge was performed twice, before and after the solid test meal. Diagnosis based on single water swallows in the supine position (Chicago Classification v3.0) was compared with results in the upright position and with provocative tests. RESULTS: Overall, diagnostic agreement in the supine and upright positions was present in 296/438 (67.6%) subjects. This increased to 90.0% when ineffective oesophageal motility was considered with normal motility. Integrated relaxation pressure was 4 mm Hg higher in the supine position. There was a higher prevalence of inconsistent, likely false positive, diagnoses of outlet obstruction in the supine compared to the upright position (16/20 vs 1/4 patients, P = 0.0007). Similarly, the difference in concordance for the diagnosis of oesophago-gastric junction obstruction or achalasia between single water swallows in the supine and upright positions with solid test meal was significant (12/29 (41.4%) vs 12/14 (85.7%), P = 0.0087). CONCLUSION: Diagnostic agreement for oesophageal motility disorders based on single water swallows in the upright and supine positions was moderate, with frequent discordant findings for ineffective motility and outlet obstruction. HRM studies can be performed in either position, using appropriate reference values. Rapid drink challenge or solid test meal can resolve diagnostic discrepancies.

A prospective randomized study of colonoscopy using blue laser imaging and white light imaging in detection and differentiation of colonic polyps.

Background and study aims Published data on blue laser imaging (BLI) for detection and differentiation of colonic polyps are limited compared to narrow band imaging (NBI). This study investigated whether BLI can increase the detection rate of colonic polyps and adenomas when compared to white light imaging (WLI), and examined use of NICE (NBI International Colorectal Endoscopic) and JNET (Japan NBI Expert Team) classifications with BLI. Patients and methods Patients aged 50 years and above referred for colonoscopy were randomized to BLI or WLI on withdrawal. Detected polyps were characterized using NICE and JNET classifications under BLI mode and correlated with histology. Primary outcome was adenoma detection rate. Secondary outcomes were utility of NICE and JNET classifications to predict histology using BLI. Results A total of 182 patients were randomized to BLI (92) or WLI (90). Comparing BLI with WLI, the polyp detection rate was 59.8 % vs 40.0 %, P  = 0.008, and the adenoma detection rate was 46.2 % vs 27.8 %, P  = 0.010. NICE 1 and JNET 1 diagnosed hyperplastic polyps with sensitivity of 87.18 % and specificity of 84.35 %. NICE 2 diagnosed low- (LGD) or high-grade dysplasia (HGD) with sensitivity of 92.31 % and specificity of 77.45 %. JNET 2A diagnosed LGD with sensitivity of 91.95 %, and specificity of 74.53 %. Four cases of focal HGD all had JNET 2A morphology. Conclusion BLI increased adenoma detection rate compared to WLI. NICE and JNET classifications can be applied when using BLI for endoscopic diagnosis of HP and LGD but histological confirmation remains crucial.

High Preponderance of BRAF V600E Mutation in Papillary Thyroid Carcinoma Among Filipinos: A Clinicopathologic Study.

PURPOSE: BRAF mutation in papillary thyroid carcinoma (PTC) is associated with an aggressive phenotype, with varying incidence. We evaluated the prevalence of BRAF mutations in PTC among Filipino patients and their correlation with clinicopathologic characteristics. PATIENTS AND METHODS: Clinicopathologic data were retrieved from 64 sequential patients who underwent thyroidectomy from June 2016 to December 2016. BRAF mutation testing was performed using Sanger sequencing. RESULTS: Eighteen (28%) of 64 patients were diagnosed with PTC; 12 (70.59%) of 17 harbored a BRAF V600E mutation (no amplification in one patient). Demographics of patients with PTC were as follows: 13 women and five men, with median age of 46 years (range, 25 to 74 years). Fourteen patients had conventional subtype PTC; two, follicular variant; one, oncocytic variant; and one, tall-cell features. Tumor size ranged from 0.8 to 7.0 cm (median, 2.4 cm); extrathyroidal extension was present in seven (38.9%) of 18 patients, multifocality in six (33.33%) of eight, and lymph node involvement in eight (44.4%) of 18. Significant association between presence of a BRAF mutation and presence of extrathyroidal extension or lymph node involvement was not determined due to the limited sample size. CONCLUSION: The high preponderance of BRAF mutation (70.59%) suggests some correlation with the previously reported lower 5-year survival among Filipinos. This warrants further investigation in a larger-cohort prospective study.

Effects of proton pump inhibitor on the human gut microbiome profile in multi-ethnic groups in Singapore.

INTRODUCTION: The objectives of this study were to examine the effects of ethnicity, gender and a proton pump inhibitor (PPI), omeprazole, on the human gut microbiome. PPIs are commonly used for the treatment of acid-related disorders. We hypothesised that PPI therapy might perturb microbial communities and alter the gut microbiome. METHODS: Healthy subjects of Chinese (n = 12), Malay (n = 12) and Indian (n = 10) ancestry, aged 21-37 years, were enrolled. They provided a baseline stool sample (Day 1) and were then given a course of omeprazole at therapeutic dose (20 mg daily) for seven days. Stool samples were collected again on Day 7 and 14 (one week after stopping omeprazole). Microbial DNA was extracted from the stool samples, followed by polymerase chain reaction, library construction, 16S rRNA sequencing using Illumina MiSeq, and statistical and bioinformatics analyses. RESULTS: The findings showed an increase in species richness (p = 0.018) after omeprazole consumption on Day 7, which reverted to baseline on Day 14. There were significant increases in the relative abundance of Streptococcus vestibularis (p = 0.0001) and Veillonella dispar (p = 0.0001) on Day 7, which diminished on Day 14. Faecalibacterium prausnitzii, Sutterella stercoricanis and Bacteroides denticanum were characteristic of Chinese, Malays and Indians, respectively. Lactobacillaceae and Bacteroides xylanisolvens were the signature taxa of male and female subjects, respectively. CONCLUSION: The study demonstrated alterations in the gut microbiome following omeprazole treatment. This may explain the underlying pathology of increased risk of Clostridium difficile infections associated with omeprazole therapy.

Abnormal esophageal motility during a solid test meal in systemic sclerosis-detection even in very early disease and association with disease progression.

OBJECTIVE: This study assessed whether high-resolution manometry (HRM) with a test meal can detect clinically relevant, abnormal motility already in very early systemic sclerosis (SSc) and whether this finding is associated with subsequent disease progression. METHODS: This prospective, longitudinal cohort study recruited 68 consecutive SSc patients (group #1: 32 established disease (ACR, American College of Rheumatology /EULAR, The European League against Rheumatism 2013 and ACR 1980 criteria fulfilled); group #2: 24 early disease (only ACR/EULAR 2013 fulfilled); group #3: 12 very early disease (clinical expert diagnosis of SSc) and 72 healthy controls. HRM evaluated esophageal motility for water swallows and a solid test meal. RESULTS: Systemic sclerosis patients had less frequent effective esophageal contractions during the test meal compared to healthy controls even in very early disease (0.15, 1.0, 2.1 per minute for groups #1, #2, and #3, vs 2.5 per minute in health; P < 0.001, P < 0.001, and P < 0.0085, respectively). Ineffective motility at HRM was associated with a higher modified Rodnan skin score at baseline. Moreover, at mean 18 (10-31) months of follow-up, the presence of ineffective motility at baseline was associated with progression of skin disease (P = 0.01). Cox proportional hazard regression analysis identified hypotensive peristalsis in the test meal (<15% effective solid swallows) and low distal contractile integral (DCI; <400 mm Hg·cm·s) as predictors for skin aggravation, but not for new organ involvement. CONCLUSION: Ineffective motility during a test meal is present already in patients with very early SSc. Findings on HRM studies are associated with disease severity at baseline, and low percentage of effective swallows in test meal and low mean DCI are both predictors of skin progression during follow-up.

Diagnostic yield of ambulatory oesophageal studies on versus off proton pump inhibitors: a systematic review and meta-analysis.

BACKGROUND: Patients with persistent gastroesophageal reflux disease symptoms despite proton pump inhibitors are increasingly encountered. It remains controversial if proton pump inhibitors should be stopped before functional oesophageal tests. AIM: This meta-analysis compares the positive yield of oesophageal studies performed off versus on proton pump inhibitors. METHODS: Pubmed, Embase and the Cochrane Library were searched for eligible studies. Outcomes assessed were the number of subjects with: elevated oesophageal acid exposure time when studied off versus on proton pump inhibitors; positive symptom index (≥50%) and/or positive symptom association probability (≥95%) for acid reflux; and/or non-acid reflux events off versus on proton pump inhibitors. The random effects model was applied. RESULTS: Fifteen studies (n = 5033 individuals; 33% on proton pump inhibitors; 32% men; mean age 52.1 years) were analysed. Pooled risk ratio for the comparison of high oesophageal acid exposure time off versus on proton pump inhibitors was 2.16 (95% confidence interval (CI) 1.42-3.28). The risk ratio of a positive symptom index (acid reflux) was 2.64 (95% CI 1.52-4.57) and the risk ratio of a positive symptom association probability (acid reflux) was 2.94 (95% CI 2.31-3.74). Conversely, the risk ratio of a positive symptom index (non-acid reflux) was 0.96 (95% CI 0.49-1.88) and risk ratio of a positive symptom association probability (non-acid reflux) was 0.54 (95% CI 0.30-0.99). CONCLUSIONS: Oesophageal studies after proton pump inhibitor cessation improve the positive yield for acid reflux-related events but reduce the detection of symptomatic non-acid reflux events.