BacteriologyEnzyme immunoassay and immunoblotting analysis of Helicobacter pylori infection in Turkish asymptomatic subjects
Introduction
Infection with Helicobacter pylori is prevalent worldwide. Reports from developing countries indicate higher infection rates than those from developed countries. The pattern of infection in developing countries is an early childhood infection that reaches over 90% during adulthood (Megraud, 1992, Bardhan, 1997), whereas infection in developed countries is less common in young children and reaches 60% in higher age groups (Axon, 1996, Go, 2002, Frenck and Clemens, 2003), suggesting rapidly improving socioeconomic conditions. Recently, Frenck and Clemens (2003) reported a 20% infection rate among adolescents in the United States in comparison to rates exceeding 90% by 5 years of age in parts of the developing world. Although the World Health Organization estimates indicate that approximately 50% of the world populations are infected with H. pylori, the majority of infected subjects develop no clinical symptoms or peptic ulceration and continue their life with superficial chronic gastritis (Hunt, 1996, Blaser, 1997, Rothenbacher and Brenner, 2003). Several factors are involved in the pathogenesis of peptic ulcer diseases; among these are the expression of the putative virulence markers, the cytotoxin-associated gene (cagA), and the vacuolating cytotoxin gene (vacA), which are shown to have a significant association with the disease (Ching et al., 1996).
The detection of H. pylori infection has been performed using either biopsy-based tests (Campylobacter-like organisms, culture, histology) and/or non–biopsy-based tests (serology, urea breath test) (Hunt, 1996). Among several serological tests, the ELISA test is widely used for the detection of H. pylori antibodies in epidemiological and post-treatment studies (Megraud, 1996, The EUROGAST Study Group, 1993, Laheij et al., 1998). Immunoblotting is another sensitive serologic test that enables the detection of antibodies against specified H. pylori antigens, such as CagA and VacA antigens (Nilsson et al., 1997, Rocha et al., 2000).
In Turkey, no detailed study is being reported. In one earlier report, it was shown that 53% of the subjects tested were seropositive for H. pylori, and more than 30% acquired the infection before age 13 (Us and Hascelik, 1998).
Because of limited data on the epidemiology of H. pylori and its associated risk factors in Turkey, our objectives were to serologically analyze H. pylori infection in asymptomatic Turkish subjects by the ELISA test, correlate infection with age, gender, education, socioeconomic and marital status, smoking, and nonsteroidal anti-inflammatory drug intake, and to evaluate the CagA status and other H. pylori antigens by immunoblotting.
Section snippets
Subjects
Three hundred nine apparently healthy asymptomatic Turkish subjects with no complaints of upper abdominal pain and no medication for the last three months were enrolled. They were a group of university students and staff members, blood donors, businessmen, nursery homers, housewives, nurses, laborers, school children, preschoolers, and infants. The age range of the subjects was 1–82 years (average: 31 years); the subjects were grouped into eight different age groups, as depicted in Fig. 1. One
Results
The IgG anti–H. pylori antibodies were detected by the ELISA test in 216 (70%) of the total of 309 asymptomatic subjects tested. Of these, 132 (61%) were male, and 84 (39%) were female. The H. pylori infection rates in these subjects were shown according to their age group (Table 1).
Subjects over 45 years of age had significantly higher antibody response to H. pylori (odds ratio = 0.16 [95% confidence interval: 0.07–0.37]) than those less than 45 years of age (p < 0.05) (Table 2). Anti–H.
Discussion
The overall H. pylori infection rate of 70% detected in our subjects appeared to be similar to our findings (76%) in a study conducted previously on Libyan asymptomatic subjects (Bakka and Salih, 2002) and to reports from Saudi Arabia and India (70%, 79%), respectively (Al-Moagel et al., 1990, Graham et al., 1991). Acquisition of infection appears obviously as an early infection during childhood with transmission modes of oral–oral and fecal–oral routes being described (Rothenbacher et al., 1999
Acknowledgements
The authors would like to thank Ms. Serap Findik and Ms. Rahsan Sahin for their technical assistance.
References (33)
- et al.
Prevalence of Helicobacter pylori infection in asymptomatic subjects in Libya
Diagn Microbiol Infect Dis
(2002) - et al.
Helicobacter in the developing world
Microbes Infect
(2003) - et al.
Antibody response to specific H pylori antigens in functional dyspepsia, duodenal ulcer disease, and health
Am J Gastroenterol
(1998) - et al.
Childhood living conditions and Helicobacter pylori seropositivity in adult life
Lancet
(1992) - et al.
Burden of Helicobacter pylori and H. pylori-related diseases in developed countries: Recent developments and future implications
Microbes Infect
(2003) - et al.
Seroprevalence of Helicobacter pylori infection in an asymptomatic Turkish population
J Infect
(1998) - et al.
Intrafamilial clustering of Helicobacter pylori infection in Saudi Arabia
Can J Gastroenterol
(2000) - et al.
Prevalence of Helicobacter (formerly Campylobacter) pylori infection in Saudi Arabia, and comparison of those with and without upper gastrointestinal symptoms
Am J Gastroenterol
(1990) The transmission of Helicobacter pylori: which theory fits the facts?
Eur J Gastroenterol Hepatol
(1996)Epidemiological features of Helicobacter pylori infection in developing countries
Clin Infect Dis
(1997)
Helicobacter pylori infection in patients consulting gastroenterologists in Franceprevalence is linked to gender and region of residence
Eur J Gastroenterol Hepatol
Prevalence of CagA-bearing Helicobacter pylori strains detected by the anti-CagA assay in patients with peptic ulcer disease and in controls
Am J Gastroenterol
When is Helicobacter pylori infection acquired?
Gut
Familial clustering of Helicobacter pylori infectionpopulation based study
BMJ
Determinants of ethnic or geographical differences in infectivity and transmissibility of Helicobacter pylori
Can J Gastroenterol
Cited by (20)
Potential link between Helicobacter pylori seropositivity and macrophage migration inhibitory factor in patients with myocardial infarction underwent primary percutaneous coronary intervention
2019, International Journal of Pharmaceutical ResearchEvaluating the relationship between serum immunoglobulin G (IgG) and A (IgA) anti-cagA antibody and the cagA gene in patients with dyspepsia
2017, Iranian Journal of Microbiology