Yutaka Yoshimizu

Seroprevalence of Helicobacter pylori infection in Nepal: Low prevalence in an isolated rural village

Objective To determine the seroprevalence of Helicobacter pylori infection in Nepal. Design H. pylori infection was identified using a specific and sensitive enzyme-linked immunosorbent assay for anti-H. pylori immunoglobulin G. Study population Serum samples were collected from 1142 inhabitants (age range 4–93 years) from two villages: Kotyang, a rural isolated village (250 men, 210 women) and Bhadrakali, a suburban village of Kathmandu (334 men, 348 women). Results The overall prevalence of H. pylori infection was 56.8%, while a significantly higher prevalence was found in the suburban village (Bhadrakali; 67.2%) than in the rural village (Kotyang; 41.5%). This difference was generally reflected by the infection rate in the 10–14-year-old age-group (Bhadrakali, 60% compared with Kotyang, 22.2%). The prevalence of infection significantly increased with age, while no significant difference was found in the prevalence of infection by gender. There was no difference in H. pylori positivity between individuals with and without upper abdominal symptoms in both villages. Conclusion There was a significant regional difference in the seroprevalence of H. pylori within Nepal, which showed lower prevalence in an isolated rural village. This difference was mainly caused by the different acquisition rate in teenagers, thus indicating that the teenage lifestyle of this particular environment seemed to be the major determinant in the acquisition of H. pylori infection in the population.

Angiotensin-converting enzyme gene polymorphism in Nepal

It has recently been found that there were very few hypertensives in the inhabitants of one Nepalese village, even though their salt consumption, per capita, was as high as citizens in many western countries. To evaluate the genetic factors involved in this phenomenon, we studied whether they had a special genotype distribution of angiotensin-converting enzyme (ACE) gene I/D polymorphism, which was recently reported to be involved in salt sensitivity.One hundred and thirty-eight subjects were evaluated in Nepal. Only nine subjects (6.5%) in this population were hypertensives (over 140/90 mm Hg) while consuming 11 g salt/day, which confirmed the previous results. The distribution of genotypes and alleles of ACE gene I/D polymorphism was similar to that in the Japanese and Chinese, who had five-times more hypertensives while consuming almost as much salt as Nepalese, but significantly different from those in Caucasians.The present study reports, for the first time, the genotype distribution of ACE gene I/D polymorphism in Nepalese subjects. Furthermore, the results suggest ACE gene polymorphism may not be involved in the ‘salt-resistance’ in this population.