MyMedR

Fulltext Benign insulinoma--a diagnostic challenge: a case report

Fock KM, Nambiar R

Med J Malaysia, 1984 Jun;39(2):170-2.

A 22-year-old Malay man with recurrent hypoglycaemic fainting spells was found to have hyperinsulinism. Although the CT scan of the abdomen and arteriogram failed to demonstrate any tumour in the pancreas, three tumours were found in the body of the pancreas at laporatomy, An appraisal of the techinques currently available for diagnosis and localisation of insulinoma is presented.

Autophagy in Helicobacter pylori Infection and Related Gastric Cancer

Castaño-Rodríguez N, Kaakoush NO, Goh KL, Fock KM, Mitchell HM

Helicobacter, 2015 Oct;20(5):353-69.

PMID: 25664588 DOI: 10.1111/hel.12211

Autophagy, a degradation pathway in which cytoplasmic content is engulfed and degraded by lysosomal hydrolases, plays a pivotal role in infection and inflammation. Given that defects in autophagy lead to increased susceptibility to infection, we investigated the role of autophagy in Helicobacter pylori-related gastric cancer (GC).

Genetic polymorphisms in the Toll-like receptor signalling pathway in Helicobacter pylori infection and related gastric cancer

Castaño-Rodríguez N, Kaakoush NO, Pardo AL, Goh KL, Fock KM, Mitchell HM

Hum Immunol, 2014 Aug;75(8):808-15.

PMID: 24929142 DOI: 10.1016/j.humimm.2014.06.001

Gastric cancer (GC) is a progressive process initiated by Helicobacter pylori-induced inflammation. Initial recognition of H. pylori involves Toll-like receptors (TLRs), central molecules in the host inflammatory response. Here, we investigated the association between novel polymorphisms in genes involved in the TLR signalling pathway, including TLR2, TLR4, LBP, MD-2, CD14 and TIRAP, and risk of H. pylori infection and related GC.

Fulltext The NOD-like receptor signalling pathway in Helicobacter pylori infection and related gastric cancer: a case-control study and gene expression analyses

Castaño-Rodríguez N, Kaakoush NO, Goh KL, Fock KM, Mitchell HM

PLoS One, 2014;9(6):e98899.

PMID: 24901306 DOI: 10.1371/journal.pone.0098899

Currently, it is well established that cancer arises in chronically inflamed tissue. A number of NOD-like receptors (NLRs) form inflammasomes, intracellular multiprotein complexes critical for generating mature pro-inflammatory cytokines (IL-1β and IL-18). As chronic inflammation of the gastric mucosa is a consequence of Helicobacter pylori infection, we investigated the role of genetic polymorphisms and expression of genes involved in the NLR signalling pathway in H. pylori infection and related gastric cancer (GC).

Distinct cagA EPIYA motifs are associated with ethnic diversity in Malaysia and Singapore

Schmidt HM, Goh KL, Fock KM, Hilmi I, Dhamodaran S, Forman D, et al.

Helicobacter, 2009 Aug;14(4):256-63.

PMID: 19674129 DOI: 10.1111/j.1523-5378.2009.00684.x

In vitro studies have shown that the biologic activity of CagA is influenced by the number and class of EPIYA motifs present in its variable region as these motifs correspond to the CagA phosphorylation sites. It has been hypothesized that strains possessing specific combinations of these motifs may be responsible for gastric cancer development. This study investigated the prevalence of cagA and the EPIYA motifs with regard to number, class, and patterns in strains from the three major ethnic groups within the Malaysian and Singaporean populations in relation to disease development.

The cag PAI is intact and functional but HP0521 varies significantly in Helicobacter pylori isolates from Malaysia and Singapore

Schmidt HM, Andres S, Nilsson C, Kovach Z, Kaakoush NO, Engstrand L, et al.

Eur J Clin Microbiol Infect Dis, 2010 Apr;29(4):439-51.

PMID: 20157752 DOI: 10.1007/s10096-010-0881-7

Helicobacter pylori-related disease is at least partially attributable to the genotype of the infecting strain, particularly the presence of specific virulence factors. We investigated the prevalence of a novel combination of H. pylori virulence factors, including the cag pathogenicity island (PAI), and their association with severe disease in isolates from the three major ethnicities in Malaysia and Singapore, and evaluated whether the cag PAI was intact and functional in vitro. Polymerase chain reaction (PCR) was used to detect dupA, cagA, cagE, cagT, cagL and babA, and to type vacA, the EPIYA motifs, HP0521 alleles and oipA ON status in 159 H. pylori clinical isolates. Twenty-two strains were investigated for IL-8 induction and CagA translocation in vitro. The prevalence of cagA, cagE, cagL, cagT, babA, oipA ON and vacA s1 and i1 was >85%, irrespective of the disease state or ethnicity. The prevalence of dupA and the predominant HP0521 allele and EPIYA motif varied significantly with ethnicity (p < 0.05). A high prevalence of an intact cag PAI was found in all ethnic groups; however, no association was observed between any virulence factor and disease state. The novel association between the HP0521 alleles, EPIYA motifs and host ethnicity indicates that further studies to determine the function of this gene are important.

Racial differences in Helicobacter pylori, serum pepsinogen and gastric cancer incidence in an urban Asian population

Ang TL, Fock KM, Dhamodaran S, Teo EK, Tan J

J Gastroenterol Hepatol, 2005 Oct;20(10):1603-9.

PMID: 16174081

In Singapore, the highest incidence of gastric cancer occurs in the Chinese (C), with lower rates among Malay (M) and Indian (I) subjects. The purpose of the present paper was to examine whether racial differences in the prevalence of Helicobacter pylori and serum pepsinogen (PG) could account for this difference.

Gastro-oesophageal reflux disease in Asia

Goh KL, Chang CS, Fock KM, Ke M, Park HJ, Lam SK

J Gastroenterol Hepatol, 2000 Mar;15(3):230-8.

PMID: 10764021

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.

Fulltext Dysbiosis of the microbiome in gastric carcinogenesis

Castaño-Rodríguez N, Goh KL, Fock KM, Mitchell HM, Kaakoush NO

Sci Rep, 2017 11 21;7(1):15957.

PMID: 29162924 DOI: 10.1038/s41598-017-16289-2

The gastric microbiome has been proposed as an etiological factor in gastric carcinogenesis. We compared the gastric microbiota in subjects presenting with gastric cancer (GC, n = 12) and controls (functional dyspepsia (FD), n = 20) from a high GC risk population in Singapore and Malaysia. cDNA from 16S rRNA transcripts were amplified (515F-806R) and sequenced using Illumina MiSeq 2 × 250 bp chemistry. Increased richness and phylogenetic diversity but not Shannon's diversity was found in GC as compared to controls. nMDS clustered GC and FD subjects separately, with PERMANOVA confirming a significant difference between the groups. H. pylori serological status had a significant impact on gastric microbiome α-diversity and composition. Several bacterial taxa were enriched in GC, including Lactococcus, Veilonella, and Fusobacteriaceae (Fusobacterium and Leptotrichia). Prediction of bacterial metabolic contribution indicated that serological status had a significant impact on metabolic function, while carbohydrate digestion and pathways were enriched in GC. Our findings highlight three mechanisms of interest in GC, including enrichment of pro-inflammatory oral bacterial species, increased abundance of lactic acid producing bacteria, and enrichment of short chain fatty acid production pathways.

Variation in human genetic polymorphisms, their association with Helicobacter pylori acquisition and gastric cancer in a multi-ethnic country

Schmidt HM, Ha DM, Taylor EF, Kovach Z, Goh KL, Fock KM, et al.

J Gastroenterol Hepatol, 2011 Dec;26(12):1725-32.

PMID: 21649724 DOI: 10.1111/j.1440-1746.2011.06799.x

BACKGROUND AND AIM: The contribution of human genetic polymorphisms to Helicobacter pylori infection and gastric cancer (GC) development remains unclear due to geographic variation in the association between specific host genetic polymorphisms and GC. In the current study we investigated the association between polymorphisms related to immune and cancer-related pathways and H. pylori infection among the major ethnicities, Chinese, Malay and Indian, resident in Singapore and Malaysia as well as the association between these polymorphisms and GC development in ethnic Chinese patients.

METHODS: Thirty-four polymorphisms in 26 genes were typed by mass spectrometry in 422 patients undergoing endoscopy (162 Chinese, 113 Indian and 87 Malay controls and 60 Chinese GC cases). Patients were assessed for evidence of H. pylori infection. Odds ratios (OR) and confidence intervals (CI) were obtained using logistic regression models.

RESULT: The prevalence of 16 polymorphisms varied significantly among the ethnicities. In the Chinese subgroup, nominally significant associations were shown between (i) EBBR2+1963G (rs1801200) and H. pylori infection (per-allele OR: 0.48, 95% CI 0.23, 0.98, P = 0.04), (ii) PTGS2-1195G (rs689466) and an increased risk of GC on adjusting for H. pylori status (OR: 1.53, 95% CI 0.99, 2.37, P = 0.05), and (iii) IL1B-1473C (rs1143623) and a decreased risk of GC (OR: 0.64, 95% CI 0.41, 0.99, P = 0.05). Borderline significant associations were seen between IL2-330G (rs2069762) (OR 1.45, 95% CI 0.95, 2.15, P = 0.06) and IL13-1111T (rs1800925) (OR 0.65, 95% CI 0.42, 1.01, P = 0.06) and H. pylori infection.

CONCLUSION: These findings contribute to the understanding of the genetic variation between ethnicities, which may influence H. pylori susceptibility and the outcome of infection.

The neurological manifestations of Nipah virus encephalitis, a novel paramyxovirus

Lee KE, Umapathi T, Tan CB, Tjia HT, Chua TS, Oh HM, et al.

Ann Neurol, 1999 Sep;46(3):428-32.

PMID: 10482278 DOI: 10.1002/1531-8249(199909)46:3<428::AID-ANA23>3.0.C

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.

Fulltext The prevalence of the duodenal ulcer promoting gene (dupA) in Helicobacter pylori isolates varies by ethnic group and is not universally associated with disease development: a case-control study

Schmidt HM, Andres S, Kaakoush NO, Engstrand L, Eriksson L, Goh KL, et al.

Gut Pathog, 2009;1(1):5.

PMID: 19338650 DOI: 10.1186/1757-4749-1-5

The putative H. pylori pathogenicity-associated factor dupA has been associated with IL-8 induction in vitro, and duodenal ulcer (DU) and gastric cancer (GC) development in certain populations, but this association is inconsistent between studies. We aimed to investigate dupA prevalence in clinical isolates from Sweden, Australia and from ethnic Chinese, Indians and Malays resident in Malaysia and Singapore and to examine the association with DU and GC. In addition we investigated the sequence diversity between isolates from these diverse groups and compared the level of IL-8 secretion in isolates possessing and lacking dupA.

Asia-Pacific consensus on the management of gastro-oesophageal reflux disease: an update focusing on refractory reflux disease and Barrett's oesophagus

Fock KM, Talley N, Goh KL, Sugano K, Katelaris P, Holtmann G, et al.

Gut, 2016 Sep;65(9):1402-15.

PMID: 27261337 DOI: 10.1136/gutjnl-2016-311715

OBJECTIVE: Since the publication of the Asia-Pacific consensus on gastro-oesophageal reflux disease in 2008, there has been further scientific advancement in this field. This updated consensus focuses on proton pump inhibitor-refractory reflux disease and Barrett's oesophagus.

METHODS: A steering committee identified three areas to address: (1) burden of disease and diagnosis of reflux disease; (2) proton pump inhibitor-refractory reflux disease; (3) Barrett's oesophagus. Three working groups formulated draft statements with supporting evidence. Discussions were done via email before a final face-to-face discussion. We used a Delphi consensus process, with a 70% agreement threshold, using Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria to categorise the quality of evidence and strength of recommendations.

RESULTS: A total of 32 statements were proposed and 31 were accepted by consensus. A rise in the prevalence rates of gastro-oesophageal reflux disease in Asia was noted, with the majority being non-erosive reflux disease. Overweight and obesity contributed to the rise. Proton pump inhibitor-refractory reflux disease was recognised to be common. A distinction was made between refractory symptoms and refractory reflux disease, with clarification of the roles of endoscopy and functional testing summarised in two algorithms. The definition of Barrett's oesophagus was revised such that a minimum length of 1 cm was required and the presence of intestinal metaplasia no longer necessary. We recommended the use of standardised endoscopic reporting and advocated endoscopic therapy for confirmed dysplasia and early cancer.

CONCLUSIONS: These guidelines standardise the management of patients with refractory gastro-oesophageal reflux disease and Barrett's oesophagus in the Asia-Pacific region.

A multicenter randomized comparison between high-definition white light endoscopy and narrow band imaging for detection of gastric lesions

Ang TL, Pittayanon R, Lau JY, Rerknimitr R, Ho SH, Singh R, et al.

Eur J Gastroenterol Hepatol, 2015 Dec;27(12):1473-8.

PMID: 26426836 DOI: 10.1097/MEG.0000000000000478

Narrow band imaging (NBI) is generally considered to be useful for lesion characterization, but not enhanced detection of gastric lesions, because of the dark endoscopic view. We tested whether the new generation of NBI (190-NBI or 290-NBI), which is twice as bright as the previous version, would improve detection of premalignant gastric lesions compared with high-definition white light endoscopy (HD-WLE).

Asia Pacific Consensus Statements on Crohn's disease. Part 1: Definition, diagnosis, and epidemiology: (Asia Pacific Crohn's Disease Consensus--Part 1)

Ooi CJ, Makharia GK, Hilmi I, Gibson PR, Fock KM, Ahuja V, et al.

J Gastroenterol Hepatol, 2016 Jan;31(1):45-55.

PMID: 25819140 DOI: 10.1111/jgh.12956

Inflammatory bowel disease (IBD) was previously thought to be rare in Asia, but emerging data indicate rising incidence and prevalence of IBD in the region. The Asia Pacific Working Group on Inflammatory Bowel Disease was established in Cebu, Philippines, at the Asia Pacific Digestive Week conference in 2006 under the auspices of the Asian Pacific Association of Gastroenterology with the goal of developing best management practices, coordinating research, and raising awareness of IBD in the region. The consensus group previously published recommendations for the diagnosis and management of ulcerative colitis with specific relevance to the Asia-Pacific region. The present consensus statements were developed following a similar process to address the epidemiology, diagnosis, and management of Crohn's disease. The goals of these statements are to pool the pertinent literature specifically highlighting relevant data and conditions in the Asia-Pacific region relating to the economy, health systems, background infectious diseases, differential diagnoses, and treatment availability. It does not intend to be all comprehensive and future revisions are likely to be required in this ever-changing field.

Asia-Pacific consensus statements on Crohn's disease. Part 2: Management

Ooi CJ, Makharia GK, Hilmi I, Gibson PR, Fock KM, Ahuja V, et al.

J Gastroenterol Hepatol, 2016 Jan;31(1):56-68.

PMID: 25819311 DOI: 10.1111/jgh.12958

The Asia Pacific Working Group on Inflammatory Bowel Disease was established in Cebu, Philippines, at the Asia Pacific Digestive Week conference in 2006 under the auspices of the Asian Pacific Association of Gastroenterology (APAGE) with the goal of developing best management practices, coordinating research and raising awareness of IBD in the region. The consensus group previously published recommendations for the diagnosis and management of ulcerative colitis (UC) with specific relevance to the Asia-Pacific region. The present consensus statements were developed following a similar process to address the epidemiology, diagnosis and management of Crohn's disease (CD). The goals of these statements are to pool the pertinent literature specifically highlighting relevant data and conditions in the Asia-Pacific region relating to the economy, health systems, background infectious diseases, differential diagnoses and treatment availability. It does not intend to be all-comprehensive and future revisions are likely to be required in this ever-changing field.

Helicobacter pylori management in ASEAN: The Bangkok consensus report

Mahachai V, Vilaichone RK, Pittayanon R, Rojborwonwitaya J, Leelakusolvong S, Maneerattanaporn M, et al.

J Gastroenterol Hepatol, 2018 Jan;33(1):37-56.

PMID: 28762251 DOI: 10.1111/jgh.13911

Helicobacter pylori (H. pylori) infection remains to be the major cause of important upper gastrointestinal diseases such as chronic gastritis, peptic ulcer, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. H. pylori management in ASEAN: the Bangkok consensus report gathered key opinion leaders for the region to review and evaluate clinical aspects of H. pylori infection and to develop consensus statements, rationales, and grades of recommendation for the management of H. pylori infection in clinical practice in ASEAN countries. This ASEAN Consensus consisted of 34 international experts from 10 ASEAN countries, Japan, Taiwan, and the United States. The meeting mainly focused on four issues: (i) epidemiology and disease association; (ii) diagnostic tests; (iii) management; and (iv) follow-up after eradication. The final results of each workshop were presented for consensus voting by all participants. Statements, rationale, and recommendations were developed from the available current evidence to help clinicians in the diagnosis and treatment of H. pylori and its clinical diseases.

Uniting the global gastroenterology community to meet the challenge of climate change and non-recyclable waste

Leddin D, Omary MB, Veitch A, Metz G, Amrani N, Aabakken L, et al.

Gut, 2021 11;70(11):2025-2029.

PMID: 34620696 DOI: 10.1136/gutjnl-2021-325789

Uniting the Global Gastroenterology Community to Meet the Challenge of Climate Change and Non-Recyclable Waste

Leddin D, Omary MB, Veitch A, Metz G, Amrani N, Aabakken L, et al.

Gastroenterology, 2021 11;161(5):1354-1360.

PMID: 34629165 DOI: 10.1053/j.gastro.2021.08.001

Uniting the Global Gastroenterology Community to Meet the Challenge of Climate Change and Nonrecyclable Waste

Leddin D, Omary MB, Veitch A, Metz G, Amrani N, Aabakken L, et al.

J Clin Gastroenterol, 2021 10 8;55(10):823-829.

PMID: 34617932 DOI: 10.1097/MCG.0000000000001619

Climate change has been described as the greatest public health threat of the 21st century. It has significant implications for digestive health. A multinational team with representation from all continents, excluding Antarctica and covering 18 countries, has formulated a commentary which outlines both the implications for digestive health and ways in which this challenge can be faced.

Displaying publications 1 - 20 of 21 in total