Kwong-Ming Fock

Review article: the epidemiology and prevention of gastric cancer

Gastric cancer can be divided into cardia and noncardia gastric adenocarcinoma (NCGA). Non cardia gastric cancer is a disease that has declined in global incidence but has remained as an extremely lethal cancer.

Gastro-oesophageal reflux disease in Asia

Gastro‐oesophageal reflux disease (GORD) occurs more frequently in Europe and North America than in Asia but its prevalence is now increasing in many Asian countries. Many reasons have been given for the lower prevalence of GORD in Asia. Low dietary fat and genetically determined factors, such as body mass index and maximal acid output, may be important. Other dietary factors appear to be less relevant. Increased intake of carbonated drinks or aggravating medicines may influence the increasing rates of GORD in some Asian countries but no strong evidence links other factors, such as the age of the population, smoking or alcohol consumption, to GORD. The management of GORD in Asia is similar to that in Europe and North America but the lower incidence of severe oesophagitis in Asia may alter the approach slightly. Also, because Asians tend to develop stomach cancer at an earlier age, endoscopy is used routinely at an earlier stage of investigation. Gastro‐oesophageal reflux disease is essentially a motility disorder, so short‐term management of the disease can usually be achieved using prokinetic agents (or histamine (H2)‐receptor antagonists). More severe and recurrent GORD may require proton pump inhibitors (PPI) or a combination of prokinetic agents and PPI. The choice of long‐term treatment may be influenced by the relative costs of prokinetic agents and PPI.

The neurological manifestations of Nipah virus encephalitis, a novel paramyxovirus

A novel Hendra‐like paramyxovirus named Nipah virus (NiV) was the cause of an outbreak among workers from one abattoir who had contact with pigs. Two patients had only respiratory symptoms, while 9 patients had encephalitis, 7 of whom are described in this report. Neurological involvement was diverse and multifocal, including aseptic meningitis, diffuse encephalitis, and focal brainstem involvement. Cerebellar signs were relatively common. Magnetic resonance imaging scans of the brain showed scattered lesions. IgM antibodies against Hendra virus (HeV) were present in the serum of all patients. Two patients recovered completely. Five had residual deficits 8 weeks later.

Racial differences in the prevalence of ulcerative colitis and Crohn's disease in Singapore.

Background : The aim of this study was to determine the prevalence rates of inflammatory bowel disease in the different races in Singapore.

Management consensus of inflammatory bowel disease for the Asia-Pacific region.

At the present there are no large‐scale epidemiologic data on inflammatory bowel disease (IBD) in the Asia–Pacific region, but several studies have shown an increased incidence and prevalence of IBD in this region. Compared to the West, there appears to exist a time lag phenomenon. With regard to the two main forms of IBD, ulcerative colitis (UC) is more prevalent than Crohns disease (CD). In addition to geographic differences, ethnic differences have been observed in the multiracial Asian countries. Moreover, the genetic backgrounds are different in the Asian compared to Western patients. For instance, NOD2/CARD15 variants have not been found in Asian CD patients. In general, the clinical course of IBD seems to be less severe in the Asia–Pacific region than in Western countries. Diagnosis of IBD in this region poses special problems. The lack of a gold standard for the diagnosis of IBD, and the existence of a variety of infectious enterocolitis with similar manifestations to those of IBD make the differential diagnosis particularly difficult. So far, Western diagnostic criteria have been introduced for the diagnosis of IBD. A stepwise approach to exclude non‐IBD enterocolitis also must be introduced, and a definite diagnosis must include typical histological features. In some patients, follow up and therapeutic trials might be necessary to obtain a definitive diagnosis. A better understanding of the pathogenesis of IBD will allow the development of better diagnostic markers. The management of IBD also poses some special problems in the Asia–Pacific Region. There is often a delay in using proper medications for IBD, and alternative local remedies are still widely used. With a combination of Western guidelines and regional experiences, similar principles can be used for induction and maintenance of remission. A stepwise selection of medications is advocated depending on the extent, activity and severity of the disease. Comprehensive and individualized approaches are suggested for different IBD patients. Deeper understanding of disease pathogenesis and the unique characteristics of IBD in the Asia–Pacific region, combined with reasonable and practical guidelines for drug management and the future use of biological agents would improve the therapeutic outlook of IBD in this region.

Endosonography‐ vs. endoscopic retrograde cholangiopancreatography‐based strategies in the evaluation of suspected common bile duct stones in patients with normal transabdominal imaging

Background  Endosonography (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) are highly accurate techniques for evaluating common bile duct stones.

Metronidazole-resistant Helicobacter pylori in an urban Asian population.

Background : Helicobacter pylori eradication is the mainstay in the treatment of H. pylori‐associated peptic ulcer disease. Metronidazole is an important component in most eradication regimens. However, the presence of metronidazole‐resistant H. pylori adversely affects the efficacy of such regimens. We aimed to study the prevalence of metronidazole resistance in our population, and the factors associated with its presence.

Unexplained Small-Bowel Obstruction in a Patient with Presumptive Achalasia: Need for Early Recognition of Chronic Intestinal Pseudo-obstruction (CIPO)

Chronic intestinal pseudo-obstruction (CIPO) is a rare condition characterized by impaired gastrointestinal propulsion associated with features of intestinal obstruction (IO) in the absence of any mechanical cause [1–5]. Although gut involvement may be isolated or diffuse [1], the clinical picture is dominated by small-bowel involvement [2]. In contrast, esophageal involvement is usually clinically silent despite achalasia-like features evident on barium studies [3] or on esophageal manometry [5–8]. We report a patient who was treated for achalasia 10 years prior to his first presentation for small-bowel IO, and emphasize the need to consider CIPO early in the differential diagnosis of a patient with underlying achalasia presenting with unexplained small-bowel IO. In July 1998, a 38-year-old Chinese male was referred for worsening dysphagia and regurgitation. Barium swallow and gastroscopy revealed a dilated esophagus with smooth tapering at the gastroesophageal junction. A presumptive diagnosis of achalasia was made. He responded well to serial esophageal dilatations between July 1998 and January 2003 and defaulted follow-up. He represented in January 2009 with severe abdominal distension, vomiting, and constipation. In the preceding 6 months, he had experienced intermittent episodes of abdominal bloating, weight loss, and reduced frequency of bowel movements. He did not complain of dysphagia. Clinical and radiological investigations established a diagnosis of small-bowel IO without a mechanical cause. He was treated conservatively. A colonoscopy was normal. His chest X-ray was clear. A laparotomy was performed 2 weeks later for recurrent IO. Intraoperative findings revealed multiple dilated smallbowel loops without any structural lesion. Enterotomy, evacuation of small intestinal bezoar, and appendicectomy were performed. The diagnosis of CIPO was entertained following another three admissions for subacute IO. Failure of conservative management on the third occasion led to a second laparotomy, revealing dilated small-bowel loops. Full-thickness intestinal biopsies were performed. Histology revealed a complete absence of ganglion cells and neural hypoplasia but intact smooth muscles (Fig. 1a, b), supporting a diagnosis of a neuropathic degenerative variant [9] of CIPO. Eight weeks later, a third laparotomy was required, whereby resection of a contained small-bowel perforation, adhesiolysis, and a venting ileostomy were performed. The case patient had no prior history of metabolic, neurological, cardiovascular, or pulmonary disease or history of travel to any Chaga-prone endemic areas. No The authors do not have any conflict of interests.

Editorial: risk stratification for endoscopic surveillance of metachronous gastric cancer after endoscopic resection

Patients with early gastric cancer (GC) treated by endoscopic resection (ER) are at risk of developing metachronous GC. Helicobacter pylori eradication reduces this risk. Once chronic atrophic gastritis (CAG) has occurred, patients will remain at risk despite H. pylori eradication. The current practice is to perform annual endoscopic surveillance. It would be ideal to risk stratify these patients such that the need for endoscopy can be reduced. The combination of serum pepsinogen (PG) and H. pylori serology has been proposed for use in risk stratifying patients for endoscopy during GC screening. PG I and II are produced by gastric chief cells and mucous neck cells. PG II is also produced by pyloric gland cells. As CAG develops, chief cells are replaced by pyloric glands, leading to a decrease in PG I without PG II change. Low PG I with low PG I: II ratio is a marker of CAG. In severe H. pylori-induced inflammation without atrophy, PG II can be elevated, resulting in normal PG I but low PG I:II ratio. This has been associated with higher GC risk. In the ABC method of categorising gastritis severity, group A is H. pylori negative with normal PG and minimal risk for GC. The risk progressively increases from group B (H. pylori positive; PG normal) to C (H. pylori positive; PG low) and D (H. pylori negative; PG low). Kwon examined whether PG can predict the risk for metachronous GC after ER and investigated the effects of H. pylori eradication on metachronous GC incidence. Persistent H. pylori infection and low PG I:II ratio were risk factors for metachronous GC. PG I:II ratio increased after successful H. pylori eradication but there was no relationship with metachronous GC occurrence. Iguchi previously also reported that low PG I:II ratio was significantly associated with metachronous GC. PG levels can normalise after successful H. pylori eradication in the absence of CAG, but this may take 1215 months. The sensitivity and specificity of low PG for CAG from a meta-analysis were 0.69 (95% CI: 0.55-0.80) and 0.88 (95% CI: 0.77-0.94) respectively, while that for GC screening were 0.70 (95% CI: 0.66-0.75) and 0.79 (95% CI: 0.79-0.80) respectively. Another meta-analysis reported that PG (hazard ratio [HR], 3.5; 95% CI: 2.74.7) and H. pylori serology (summary HR, 3.2; 95% CI: 2.0-5.2) could discriminate between asymptomatic adults at high and low risk of GC. PG is not a tumour marker. It indicates CAG occurrence and reflects cancer risk. It cannot be used for GC screening but can help risk stratification. There is uncertainty about how PG levels change and whether they accurately reflect gastric mucosa status after H. pylori eradication. Extensive intestinal metaplasia without CAG is a risk factor for GC but will not be reflected by PG levels. Patients hesitant about endoscopic surveillance after ER may be counselled of their risk based on PG levels but would need to be aware of the limitations in order to make an informed decision on repeat endoscopy.

Optimising the care of patients with cirrhosis and gastrointestinal haemorrhage

SIRS, The recent paper by Johnson et al. brought forth some important points in the management of a complex clinical situation. In the study, these practices were bundled together, and there was an improvement in clinical outcome with administration of prophylactic antibiotics within 24 h and somatostatin singly, and also as a composite measure. Although there was no decrease in the hospital length of stay, there was a significant decrease in 30-day readmissions. The study also confirmed the current guidelines that the use of PPI is not evidence-based. An intervention bundle is not a new concept. The bundle for clinical care put together a series of best practices to ensure improved outcomes for a group of patients who require complex management across various disciplines. This is to ensure consistency in instituting best practice for almost all patients. Various bundles have shown improvements in outcomes including prevention of ventilator associated pneumonia for intubated patients and septic shock resuscitation. 3 Most clinicians assume that a combination of best practices result in improved outcomes. However, this assumption needed to be proven before adoption can be strongly encouraged. Just like combining antibiotics, there can be additive, synergistic or even antagonistic effects. Looking at the results from the current study, it appears that the positive effect is, at best, additive. How do we push the frontiers from here? Although there are studies conducted on newer coagulating agents or other methods to secure haemostasis in patients with variceal bleeding, 5 and on extra-corporeal liver assist device with synthetic function, equally important are such studies that assess bundling best practices together to improve patient outcomes. The next step is to add on other best practices to the bundle to further optimise clinical outcomes. In this study, Johnson et al. did not analyse effect of timing of endotherapy on outcomes. The AASLD recommend performing endotherapy within 12 h of presentation, whilst patients in this study had their endotherapy performed within 24 h. It will be important to note if this factor affects outcome. To further improve the bundle, we suggest including the details of treatment modality as well as the time frame for each modality to be instituted. Once clearly stated, appropriate treatment can be provided upon establishment of the correct diagnosis. From the studies in septic shock patients, early administration of antibiotics is critical. Will the administration of i.v. prophylactic antibiotics within 1 h E. K. Teo & K. M. Fock Division of Gastroenterology, Department of Medicine, Changi General Hospital, Singapore. E-mail: eng_kiong_teo@cgh.com.sg