An evaluation of factors affecting Helicobacter pylori prevalence in Tibetans exiled in India

Helicobacter pylori infection is found world-wide although the epidemiology of infection has not been well defined in many geographical areas. The aims of this study were to determine the prevalence of H. pylori infection and chronic gastritis and the demographic correlates of infection in a single racial group in southern India. The sample population was selected randomly from the male population register of a Tibetan refugee settlement. Demographic data and results of endoscopy with antral mucosal biopsy were evaluated in 197 subjects (median age 28, range 21-81 years). H. pylori was present in 77.2% of subjects by histology and/or urease test. Chronic gastritis and H. pylori were closely related and there was an association between the number of bacteria present and the severity of the gastritis (P < 0.04). Infection with H. pylori was inversely associated with socio-economic factors, specifically educational level (P < 0.02) and occupation (P < 0.02). Unlike other studies, the prevalence of H. pylori was not found to rise with age, being lower in those older than 40 years (P < 0.005). This difference was still apparent when adjusted for socio-economic status. The major demographic difference between younger and older subjects of low socio-economic status was the greater proportion of early life spent outside India (and in Tibet) by older subjects. Among younger subjects, residence in India for 20 years or more was associated with a greater risk of H. pylori infection (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Field evaluation of a rapid, simple and inexpensive urease test for the detection of Helicobacter pylori

A modified rapid urease test (MRU test) for the detection of Helicobacter pylori was evaluated under field conditions during an endoscopic survey in rural India and compared with a commercially available urease test (CLO test) and with histology. Of 195 consecutive subjects who underwent upper gastrointestinal endoscopy, 153 (78.5%) were positive for Helicobacter pylori when tested by the CLO test and/or histology. The sensitivity and specificity of the MRU test relative to this was 97.4 and 95.2%, respectively when the test was read over a 3 h period. The MRU test was positive in 77.4, 89.0, 93.8 and 96.6% of cases at 1, 5, 20 and 60 min, respectively, compared with 2.7, 14.4, 48.6 and 71.2% of cases for the CLO test at the same time. The accuracy of the MRU test was thus similar to that of other methods for the detection of Helicobacter pylori. Furthermore, it gave a positive diagnosis more rapidly than other tests, in most cases before the subject had left the endoscopy suite. The MRU test is extremely simple to prepare and read and costs less than 0.05 pounds per test compared with 2.26 pounds for a CLO test. It is suitable for use in clinical or epidemiological work and especially where cost factors are critical.

Dyspepsia, Helicobacter pylori, and peptic ulcer in a randomly selected population in India

There seems to be a worldwide geographic variation in the prevalence of peptic ulcer disease, although there are few reliable population based studies. This study aimed to determine the prevalence of peptic ulcer disease in a community in southern India and to evaluate the relationship between dyspeptic symptoms, Helicobacter pylori infection, gastritis, and peptic ulcer disease. A sample population was selected randomly from a rural monastic settlement in southern India. Subjects were interviewed using a standardised symptom and demography questionnaire then underwent upper endoscopy and antral biopsy for histology and CLO rapid urease test. Altogether 197 subjects from a population of 1499 (13.1%) were studied. All were male monks and ethnically Tibetan. The median age was 28 years (range: 21-81). None smoked or took NSAIDs. The six month period prevalence of dyspeptic symptoms was 68.5%. Current symptoms were present in 58.9% of subjects. Dyspepsia was more common in subjects aged 40 years or younger (p < 0.0001). H pylori was detected in 77.2% subjects. There was no association between dyspepsia and the presence of H pylori or histological gastritis, although there was a strong correlation between symptoms and ulcer (p < 0.003). The point prevalence of active peptic ulcer was 6.6% (13/197). All ulcers detected were either prepyloric or pyloroduodenal in location. A further 6.6% of subjects had definite evidence of scarring or deformity indicative of ulceration in the past. Subjects with past or present ulcers comprised 17.8% of dyspeptic subjects. H pylori was present in all subjects with active ulcers and in 12/13 of those with scarring. Dyspepsia, H pylori infection, gastritis, and peptic ulcer are all more common in this population than in those from developed countries. Ulcer disease, however, accounts for only a small proportion of subjects with symptoms and neither H pylori infection nor gastritis are significantly associated with the presence of dyspepsia.