E Kwok

Differential Helicobacter pylori infection rates in two contrasting gastric cancer risk regions of South China

Background: Carriers of Helicobacter pylori are believed to have a three‐ to six‐fold increased risk of developing gastric cancer. We have recently conducted a simultaneous cross‐sectional population study on the prevalence of H. pylori infection in a cohort of asymptomatic adult volunteers in two contrasting gastric cancer risk regions of South China, Hong Kong and Changle of Fujian. Their mean annual gastric cancer mortality has been approximately 7.5 and 75/100 000 population, respectively, since the beginning of the last decade. The aim of this study was to evaluate if H. pylori prevalence bears any relationship to gastric cancer mortality rates in these two southern regions of China.

Helicobacter pylori and upper gastrointestinal symptoms in bronchiectasis.

The recently reported increase in seroprevalence of Helicobacter pylori, the causative pathogen in peptic ulceration, in bronchiectasis is unexplained. Therefore, the association of antibodies directed against cytotoxin-associated gene A(CagA), whose expression indicates virulence of H. pylori, and upper gastrointestinal symptoms in patients with stable bronchiectasis and healthy volunteers evaluated. One hundred patients (mean +/- SD age 55.1+/-16.7 yrs) and 94 healthy asymptomatic subjects (54.6+/-7.6 yrs) underwent clinical and physiological assessment and serum levels of anti-H. pylori CagA were determined using standard clinical and enzyme-linked immunosorbent assay techniques. Samples were positive for anti-H. pylori CagA in 11.7% of controls and 24% of bronchiectatic subjects (p = 0.03). There was, however, no association between serum H. pylori CagA immunoglobulin G level and forced expiratory volume in one second (FEV1), forced vital capacity (FVC), sputum volume, respiratory symptoms or upper respiratory gastrointestinal symptoms (p>0.05). Patients who suffered from acid regurgitation or upper abdominal distension had significantly lower FEV1 and FVC (as a percentage of the predicted value) compared to their counterparts. The results of anticytotoxin-associated gene A measurements in this study contrasted with the previous finding that anti-Helicobacter pylori immunoglobulin G correlated with sputum volume. These findings, therefore, suggest that Helicobacter pylori, should it have a pathogenic role in bronchiectasis, could act via noncytotoxin-associated gene A-mediated mechanisms, and, in this context, gastro-oesophageal reflux might be of importance in bronchiectasis.

CagA positive strains increase the risk of gastric cancer in Hong Kong with moderate prevalence of Helicobacter pylori infection and gastric cancer mortality

This journal suppl. entitled: The American Gastroenterological Association and Digestive Disease Week

CagA does not increase the prevalence of atrophic gastritis and intestinal metaplasia in a high gastric cancer risk region in China

Second Western Pacific Helicobacter Congress, Kota Kinabalu, Sabah, Malaysia, 25-27 June 1998. In Journal of Gastroenterology and Hepatology, 1998, v. 13 no. 7, p. A94, abstract no. D15

Age is a predicting factor for the association between CagA positive Helicobacter pylori (Hp) infection and serum pepsinogen I:II ratio in a high gastric cancer risk region in China

• G1359 AGE IS A PREDICTING FACTOR FOR THE ASSOCIATION BETWEEN CagA POSITIVE HELICOBACTER PYLORI (Hp) INFECTION AND SERUM PEPSINOGEN I:II RATIO IN A HIGH GASTRIC CANCER RISK REGION IN CHINA. BCY Wone. SK Lam, CK Ching, J Ho, ST Yuen, E Kwok, WHC Hu, KC Lai, LY Ong, Z Gao, JS Chen, BW Chen, XW Jiang, XH Hou, JY Lu, WH Wang, K Miki, A Covacci. Department of Medicine & Pathology, University of Hong Kong, Hong Kong; Public Health Bureau, Changle, and Changle Institute for Cancer Research, Fujian, China, First Dept of Internal Medicine, University of Tokyo, Japan, and *Immunobiological Research Institute, Siena, Italy.