Small Intestinal Bacterial Overgrowth In Various Functional Gastrointestinal Disorders: A Case-Control Study.

INTRODUCTION: Small intestinal bacterial overgrowth (SIBO) is prevalent in irritable bowel syndrome (IBS), but its' association with other functional gastrointestinal disorders (FGIDs) is less certain. This study aimed to explore SIBO in a multi-racial Asian population with various FGIDs compared to non-FGID controls. METHODOLOGY: Consecutive Asian adults with Rome III diagnosed common FGIDs (functional dyspepsia/FD, IBS and functional constipation/FC) and non-FGID controls were subjected to glucose breath testing, with hydrogen (H2) and methane (CH4) levels determined. RESULTS: A total of 244 participants (FGIDs n = 186, controls n = 58, median age 45 years, males 36%, Malay ethnicity 76%) were recruited. FGIDs had a higher prevalence trend of SIBO compared to controls (16% FGIDs vs. 10% controls, p = 0.278) with 14% in FD, 18% in IBS and 17% in FC. Compared to controls, SIBO was associated with diarrhoea-predominant IBS (IBS-D) (24% vs. 10%, P = 0.050) but not with other types of FGIDs. IBS-D remained an independent predictor of SIBO (OR = 2.864, 95% CI 1.160-7.071, p = 0.023) but not PPI usage nor history of diabetes (both p > 0.050) at multivariate analysis. Compared to controls, SIBO in IBS-D was associated with an elevated H2 level (≥ 20 ppm from baseline) (18% vs. 3%, p = 0.017), but not CH4 levels (≥ 10 ppm) (9% vs. 7%, p = 0.493). In addition, no difference was found in the prevalence of methane-positive SIBO between chronic constipation (constipation-predominant IBS and FC) compared to controls (9% vs. 7%, P = 0.466). CONCLUSION: SIBO is prevalent amongst multi-ethnic Asian adults with and without FGIDs. Amongst various FGIDs, only IBS-D is significantly associated with SIBO.

Is There an Increasing Incidence of Gastroesophageal Junctional Adenocarcinoma and Barrett Esophagus in Asia? A Review of Diagnostic Conundrums.

BACKGROUND: Epidemiology data of gastroesophageal junction (GEJ) cancers in Asia are extremely scarce. It is hardly registered by any cancer registry in the region, and only a few reports are available. Based on existing literature works, the overall trend indicates similar or gradually increasing GEJ cancers in Asia but comparably less than the West. The increasing trend in Asia is likely a result of rising risk factors, especially of gastroesophageal reflux disease and obesity. SUMMARY: However, epidemiology data may be misleading due to several contentious diagnostic issues. The diagnostic conundrums are due to inherent complexity of the GEJ as a functional and pathological unit. Challenging diagnostic issues in Asia include the following: nonstandardized landmark of the GEJ, misclassification of Barrett esophagus, targeted versus nontargeted tissue sampling, histopathology disagreement and challenges in screening or surveillance of dysplastic BE and early GEJ cancer. The recent Asian-Pacific survey led by the Asian Barrett Consortium (ABC) has provided useful insights into these contentious issues. A key learning point from these diagnostic limitations is that the awareness of the disease and adherence to existing recommendations or guidelines are poor in the region. Key Messages: Standardization in diagnostic methodology is vital for accurate epidemiology data, and this can only come from better awareness and adherence through educational and international efforts. Last, surveillance strategy may need a paradigm shift from a purely diagnostic approach to a combined targeted surveillance and treatment approach using novel endoscopic techniques.

Is Gut Involvement a Cause or Effect of COVID-19?

Digestive disorder symptoms in COVID-19 may be similar in form to post-infectious functional gastrointestinal disorder (PI-FGID). To cause clinical effects, SARS-CoV-2 must reach the bowels and gastric hypochlorhydria may facilitate such transit. Asian elderly are predisposed to greater infection rate and severity of COVID-19, and the high prevalence of gastric atrophy and intake of proton-pump inhibitor in this aged group might explain the risk. Persistence shedding of SARS-CoV-2 in stools indicates that faecal transmission should not be disregarded. Gut involvement in COVID-19 is mediated by angiotensin-converting enzyme 2 (ACE2) receptor, which serves as the entry point for SARS-CoV-2 in the small bowel. ACE2 dysregulation has an impact on the homeostasis of gut microbiota and altered inflammatory response. Liver injury is variable in COVID-19 and is likely a result of by-stander effects rather than actual viropathic process. Further research is needed to understand if gut involvement is a cause or effect of SARS-CoV-2.

Diagnosis and management of fatty liver.

Globally, the prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing rapidly and constitutes a significant healthcare burden due to associated complications including hepatic (cirrhosis and hepatocellular cancer) and non-hepatic (cardiovascular deaths) disorders. It is closely linked to insulin resistance and metabolic syndrome but moderate alcohol consumption frequently coexists. Recently, genetic polymorphisms were implicated in the development of non-obese NAFLD. Apart from liver biopsy, in order to assess for steatosis, fibrosis and non-alcoholic steatohepatitis (NASH), advances in non-invasive serum tests and elastography have provided similarly accurate, more accessible and safer alternatives for risk stratification. As for treatment in 2020, weight loss and lifestyle modification remain the central strategy. Unfortunately, no pharmacological agents have been approved thus far, but there are a number of potential therapies in the pipeline for fibrosis and NASH. Treatment of underlying metabolic disorders is important. While the term NAFLD was coined in the 1980s, more recent understanding may support a change in nomenclature highlighting its strong metabolic roots.