Yeong Yeh Lee

Central Obesity in Asymptomatic Volunteers Is Associated With Increased Intrasphincteric Acid Reflux and Lengthening of the Cardiac Mucosa

BACKGROUND & AIMS In the West, a substantial proportion of subjects with adenocarcinoma of the gastric cardia and gastroesophageal junction have no history of reflux. We studied the gastroesophageal junction in asymptomatic volunteers with normal and large waist circumferences (WCs) to determine if central obesity is associated with abnormalities that might predispose individuals to adenocarcinoma. METHODS We performed a study of 24 healthy, Helicobacter pylori-negative volunteers with a small WC and 27 with a large WC. Abdominal fat was quantified by magnetic resonance imaging. Jumbo biopsy specimens were taken across the squamocolumnar junction (SCJ). High-resolution pH-metry (12 sensors) and manometry (36 sensors) were performed in upright and supine subjects before and after a meal; the SCJ was visualized fluoroscopically. RESULTS The cardiac mucosa was significantly longer in the large WC group (2.5 vs 1.75 mm; P = .008); its length correlated with intra-abdominal (R = 0.35; P = .045) and total abdominal (R = 0.37; P = .034) fat. The SCJ was closer to the upper border of the lower esophageal sphincter (LES) in subjects with a large WC (2.77 vs 3.54 cm; P = .02). There was no evidence of excessive reflux 5 cm above the LES in either group. Gastric acidity extended more proximally within the LES in the large WC group, compared with the upper border (2.65 vs 4.1 cm; P = .027) and peak LES pressure (0.1 cm proximal vs 2.1 cm distal; P = .007). The large WC group had shortening of the LES, attributable to loss of the distal component (total LES length, 3 vs 4.5 cm; P = .043). CONCLUSIONS Central obesity is associated with intrasphincteric extension of gastric acid and cardiac mucosal lengthening. The latter might arise through metaplasia of the most distal esophageal squamous epithelium and this process might predispose individuals to adenocarcinoma.

Helicobacter pylori Infection – A Boon or a Bane: Lessons from Studies in a Low-Prevalence Population

Helicobacter pylori (H. pylori) infection is etiologically associated with gastric cancer and peptic ulcer diseases which are both important public health burdens which could be largely eliminated by H. pylori eradication. However, some investigators urge caution based on the hypothesis that eradication of H. pylori may result in an increase in the incidence of gastroesophageal reflux disease, esophageal adenocarcinoma, and childhood asthma. The ethnic Malays of northeastern Peninsular Malaysia have long had a low prevalence of H. pylori infection and, as expected, the incidence of gastric cancer and its precursor lesions is exceptionally low. The availability of a population with a low H. pylori prevalence and generally poor sanitation allows separation of H. pylori from the hygiene hypothesis and direct testing of whether absence of H. pylori is associated with untoward consequence. Contrary to predictions, in Malays, erosive esophagitis, Barretts esophagus, distal esophageal cancers, and childhood asthma are all of low incidence. This suggests that H. pylori is not protective rather the presence of H. pylori infection is likely a surrogate for poor hygiene and not an important source of antigens involved in the hygiene hypothesis. Helicobacter pylori in Malays is related to transmission from H. pylori‐infected non‐Malay immigrants. The factors responsible for low H. pylori acquisition, transmission, and burden of H. pylori infection in Malays remain unclear and likely involves a combination of environmental, host (gene polymorphisms), and strain virulence factors. Based on evidence from this population, absence of H. pylori infection is more likely to be boon than a bane.

Sociocultural and Dietary Practices Among Malay Subjects in the North-Eastern Region of Peninsular Malaysia: A Region of Low Prevalence of Helicobacter pylori Infection

Background and Aim:  The prevalence of Helicobacter pylori infection is exceptionally low among the Malays in the north‐eastern region of Peninsular Malaysia. The reasons are unknown. Our aim was to compare environmental factors that differed in relation to H. pylori prevalence among Malays born and residing in Kelantan.

Mechanism of association between BMI and dysfunction of the gastro-oesophageal barrier in patients with normal endoscopy

Introduction The association between body mass index (BMI) and gastro-oesophageal pressure gradient (GOPG) is incompletely understood. We examined the association between BMI and gastro-oesophageal (GO) barrier function and the effect of mechanically increasing intra-abdominal pressure on GO physiology. Methods (A) 103 dyspeptic patients with normal endoscopy underwent 24 h pH-metry and upper gastrointestinal manometry. Relationships between BMI and acid reflux, intragastric pressure (IGP), GOPG and lower oesophageal sphincter (LOS) pressure were calculated using bivariate correlations. (B) In 18 healthy volunteers, the effects of increasing IGP by abdominal belt on GO manometry were studied. Results (A) There was a linear correlation between BMI and oesophageal acid exposure in erect (R=0.35, p<0.001) and supine (R=0.40, p<0.001) positions. BMI was strongly associated with IGP (inspiration: R=0.66, p<0.001; expiration: R=0.78, p<0.001) and inspiratory GOPG (R=0.50, p<0.001). There were a positive correlation between BMI and inspiratory LOS pressure relative to atmospheric pressure (R=0.29, p=0.016) and a negative correlation with LOS pressure relative to IGP on expiration (R=−0.25, p=0.018). Logistic regression models using all significant manometric variables and relevant interactions revealed marked decline in the magnitude and significance of relationship between BMI and oesophageal acid exposure in supine (from OR 1.12 (95% CI 1.03 to 1.22), p=0.009, to 1.00 (0.86 to 1.17), p=0.999) and upright positions (from 1.11 (1.02 to 1.20), p=0.020, to 1.03 (0.89 to 1.18), p=0.717). (B) Application of the constricting abdominal belt produced similar manometric changes to those associated with increased BMI. However, the belt did not reproduce the reduced LOS pressure relative to IGP. Conclusion The association between reflux and BMI may be largely explained by effects of increased intra-abdominal pressure. However, the reduced LOS pressure associated with BMI may be mediated by another mechanism or effects of chronic rather than acute elevation of intra-abdominal pressure.

An Open-Label Pilot Study to Assess the Efficacy and Safety of Virgin Coconut Oil in Reducing Visceral Adiposity

Introduction. This is an open-label pilot study on four weeks of virgin coconut oil (VCO) to investigate its efficacy in weight reduction and its safety of use in 20 obese but healthy Malay volunteers. Methodology. Efficacy was assessed by measuring weight and associated anthropometric parameters and lipid profile one week before and one week after VCO intake. Safety was assessed by comparing organ function tests one week before and one week after intake of VCO. Paired t-test was used to analyse any differences in all the measurable variables. Results. Only waist circumference (WC) was significantly reduced with a mean reduction of 2.86 cm or 0.97% from initial measurement (P = .02). WC reduction was only seen in males (P < .05). There was no change in the lipid profile. There was a small reduction in creatinine and alanine transferase levels. Conclusion. VCO is efficacious for WC reduction especially in males and it is safe for use in humans.

WSES guidelines for management of Clostridium difficile infection in surgical patients

In the last two decades there have been dramatic changes in the epidemiology of Clostridium difficile infection (CDI), with increases in incidence and severity of disease in many countries worldwide. The incidence of CDI has also increased in surgical patients. Optimization of management of C difficile, has therefore become increasingly urgent. An international multidisciplinary panel of experts prepared evidenced-based World Society of Emergency Surgery (WSES) guidelines for management of CDI in surgical patients.

Small intestinal bacterial overgrowth: duodenal aspiration vs glucose breath test

The diagnosis of small intestinal bacterial overgrowth (SIBO) remains challenging. Our aim was to examine the diagnostic yield of duodenal aspiration/culture and glucose breath test (GBT), and effects of gender, race and demographics on prevalence of SIBO.

High Resolution and High Definition Anorectal Manometry and Pressure Topography: Diagnostic Advance or a New Kid on the Block?

The recent development of closely spaced circumferential solid state transducers has paved the way for novel technology that includes high resolution anorectal manometry and topography (HRAM) and 3-D high definition anorectal manometry (HDAM). These techniques are increasingly being used for the assessment of anorectal neuromuscular function. However, whether they constitute a diagnostic advantage or a mere refinement of an old technology is unknown. Unlike the traditional manometry that utilized 3 or 6 unidirectional sensors, the closely spaced circumferential arrangement facilitates superior spatiotemporal mapping of pressures at rest and during various dynamic maneuvers. HDAM can provide knowledge of the three muscles that govern the anal continence namely, the puborectalis, and the internal and external anal sphincters, and can show how they mediate the rectoanal inhibitory reflex and sensorimotor responses and the spatiotemporal orientation of these muscles. Also, anal sphincter defects can be mapped and readily detected using 3-D technology. Similarly, HRAM has facilitated confirmation and development of phenotypes of dyssynergic defecation. Recently, normative data have also been reported with HRAM and HDAM, together with the influence of age, gender, and test instructions. The greater yield of anatomical and functional information may supersede the limitations of costs, fragility, and shorter life-span associated with these new techniques. Thus, HDAM and HRAM are not just new gadgets but constitute a significant and novel diagnostic advance. However, more prospective studies are needed to better define anorectal disorders with these techniques and to confirm their superiority.

High-resolution esophageal manometry: addressing thermal drift of the manoscan system.

Background  The high resolution esophageal manometry system manufactured by Sierra Scientific Instruments is widely used. The technology is liable to ‘thermal drift’, a change in measured pressure due to change in temperature. This study aims to characterize ‘thermal drift’ and minimize its impact.

How to Assess Regional and Whole Gut Transit Time With Wireless Motility Capsule

Assessment of transit through the gastrointestinal tract provides useful information regarding gut physiology and patho-physiology. Although several methods are available, each has distinct advantages and limitations. Recently, an ingestible wireless motility capsule (WMC), similar to capsule video endoscopy, has become available that offers a less-invasive, standardized, radiation-free and office-based test. The capsule has 3 sensors for measurement of pH, pressure and temperature, and collectively the information provided by these sensors is used to measure gastric emptying time, small bowel transit time, colonic transit time and whole gut transit time. Current approved indications for the test include the evaluation of gastric emptying in gastroparesis, colonic transit in constipation and evaluation of generalised dysmotility. Rare capsule retention and malfunction are known limitations and some patients may experience difficulty with swallowing the capsule. The use of WMC has been validated for the assessment of gastrointestinal transit. The normal range for transit time includes the following: gastric emptying (2–5 hours), small bowel transit (2–6 hours), colonic transit (10–59 hours) and whole gut transit (10–73 hours). Besides avoiding the use of multiple endoscopic, radiologic and functional gastrointestinal tests, WMC can provide new diagnoses, leads to a change in management decision and help to direct further focused work-ups in patients with suspected disordered motility. In conclusion, WMC represents a significant advance in the assessment of segmental and whole gut transit and motility, and could prove to be an indispensable diagnostic tool for gastrointestinal physicians worldwide.