• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.2 no.2
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• pp.147-152
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• 1999

Purpose: The aim of this study was to evaluate the prevalence of H. pylori infection in normal preschool children. Methods: Study population consisted of 220 preschool children aged 2 to 5 years in Seoul, Korea. We measured H. pylori specific IgG antibody using the GAP test IgG kit, and samples with concentrations greater than 20 U/ml were considered positive. Results: Of the 220 children, 5 (2.3%) were positive, and thirteen (5.9%) of 220 were equivocally probable positive. Conclusion: The positive rate of H. pylori infection detected by specific IgG antibody in normal preschool children aged 2 to 5 years was approximately 2.3% to 8.2%. This prevalence rate is still high, compared to that of the West. A better knowledge of the transmission of H. pylori is crucial to formulate recommendations for lowering the rate.

• Parasites, Hosts and Diseases
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• v.21 no.2
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• pp.246-256
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• 1983

As epidemiological parameters of human paragonimiasis, the positive rates of intradermal test and the sputum/stool ekaminations have long been employed in population surveys. However, both the specificity of the intradermal test and the sensitivity of sputumjstool examination have been gradually declined as the endemicity was lowered; thus the gap between above two parameters widened. In such context, the development of a new epidemiologic parameter or tool which makes it possible to accurately discriminate the active paragonimiasis cases was necessary. In the present study, the detection rate of Paragonimus-speclac IgG antibody by micro-ELISA was evaluated as an indicator of epidemiologic status of human paragonimiasis in a population. A total of 4, 285 students and inhabitants living in Bukpyeong Myeon and Bukil Myeon, Haenam Gun, Jeonlanam Do was surveyed in October, 1983 by intradermal test first. Out of them, 244 cases (5.7%) were found positively reacted to VBS antigen of F. westermani. Out of 168 positive reactors, 7 cases (4.2%) were egg positive either by two times of sputum examination or by one stool examination. That indicated that only 0. 16% of total surveyed were confirmed as active paragonimiasis by egg detection. When sera collected from 239 positive reactors of Intradermal test were tested by micro-ELISA for their specific IgG antibody, 40 cases(16.7%) were found to be positive. All of 7 egg positive cases were again positive for specific IgG antibody. Among remaining 232 intradermal test positive cases, 33 cases were positive for IgG antibody. In contrast to those, none of 42 positive reactors to intradermal test for Cloncrchis and of 128 intradermal test negative cases showed positive for Paragcnimus-specIfic IgG antibody. The rate of specific IgG antibody as detected by micro-ELISA appeared to be increased with the wheal size of the intradermal test. When the wheal sixte was over 13mm in diameter, about 50% of them were positive for specific IgG antibody. Thirty-one specific antibody positive cases were clinically evaluated by laboratory examinations (repeated sputum examination, peripheral eosinophil count and chest roentgenogram) and by history taking. Out of them 24 cases were associated with one or more positive laboratory findings: thus considered as active paragonimiasis cases. Out of 7 lab. finding-free cases 3 revealed past history of typical paragonimiasis symptoms, suggesting that they were in chronic or in convalescent stages. The remaining 4 cases were considered as either mild or ectopic infection cases; the possibility of cross-reaction with other helminthiases could not be ruled out. From the above results, it was inferred that the detection of Paragonimus-specIfic IgG antibody by micro-ELISA was very much helpful in detecting the active cases as well as in proper evaluation of the endemicity of human paragonimiasis in a population. The convenience of mass haildling of sera in micro-ELISA was considered another superiority as an epidemiologic tool.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.4 no.1
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• pp.10-17
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• 2001

Purpose: We measured anti-H. pylori IgG in Korean elementary school children living in Shinchon area of Seoul, Korea to evaluate the influence of environmental living standards on H. pylori infection. Methods: IgG antibodies to H. pylori were measured in plasma using a commercial ELISA kit (GAP IgG Helicobacter pylori, Bio-Rad Laboratories Inc., Hercules, CA, USA). Information on environmental status such as place of birth, parental income, type of housing, number of persons in the household, parents' occupation, family history of peptic ulcer disease and gastric cancer was obtained. Statistical analysis was done by Chi-square and logistic regression test using SPSS $7.0^{TM}$ for Windows. Results: Study subjects consisted of 571 children, and the age distribution ranged from 6.0 to 13.6 years with a mean of $9.6{\pm}1.8$ years. Male-to-female ratio was 1.1:1. The seropositive rates of H. pylori infection ranged from 10.4% in children aged 6 years to 30.9% in 12 year-old group, overall 16.8%. The prevalence of H. pylori infection progressively increased with age, but there was no significant difference in seropositive rates among children in different age groups (p=0.06). Seropositive rates of anti-H. pylori IgG on the basis of gender, place of birth, parental income, type of housing, parents' occupation, family history of peptic ulcer disease and gastric cancer showed no statistically significant difference. Interestingly, however, seropositive rate of anti-H. pylori IgG showed statistical significance in relation to number of persons in the household (p=0.003; Odds ratio 1.50 by logistic regression test). Conclusion: These results suggest that number of persons in the household is the most important factor among environmental living standards, and that risk of H. pylori infection increases by increment of 1.5 times as the number of persons in the household increases by one.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.15 no.2
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• pp.85-90
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• 2012

Purpose: Commercial enzyme-linked immunosorbent assay (ELISA) kits have been considered less reliable for children than for adults. The aim of this study was to compare four ELISA kits and in-house immunoblotting based on the analysis of anti-H. pylori-IgG antibody reactivity. Methods: A total of 399 serum samples were collected at the GNU Hospital during 1998-1999. All sera were tested using ELISA and immunoblotting. Statistically significant differences were determined by the $x^2$ test. Results: The overall seropositivity rates using GAP IgG, Genedia IgG, HM-CAP, Pyloriset EIA-G, and immunoblotting were 13.0%, 25.1%, 18.3%, 15.8%, and 62.9%, respectively. Immunoblotting showed a higher seropositivity rate than did all four ELISA kits in all age groups. Genedia IgG had the highest seropositivity among the ELISA kits. The seropositivity rate for children aged 13 to 18 months was lowest, and that of children aged 15 years was highest (90.0%). The seropositivity rate for children aged 7 months to 5 years was significantly lower than that for children aged 6 to 15 years among the four ELISA kits (p<0.0001) and immunoblotting (p=0.02). Conclusion: Immunoblotting is the most sensitive test for detection of anti-Helicobacter pylori IgG antibodies among the serological tests in this study. These results emphasize the need for standardization when commercial ELISA tests are used in different nations or in young age groups. Immunoblotting could be a suitable noninvasive assay for serodiagnosis and seroepidemiologic study of H. pylori infection in Korean children.

• Journal of Gastric Cancer
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• v.3 no.2
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• pp.97-103
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• 2003

Purpose: This study aims to determine the infection rate of Helicobacter pylori (H. pylori) in gastric cancer patients who received gastrectomies, and to compare the rates of H.pylori infection detected by serological test and that of histopathological test, and to evaluate its clinical meaning. Materials and Methods: Fifty two patients were selected from those who underwent gastrectomies at the Department of Surgery, Samsung Medical Center, from March 1997 to May 1997. The control group consisted of healthy 103 persons visited the center for health promotion in Samsung Medical Center. In both groups, we quantitatively checked serum level of IgG anti H. pylori antibody titer by ELISA using GAP IgG test kit (BioRad, USA) for the serological test, and we microscopically examined the surgical specimen stained by Warthin-Starry silver staining method for the histopathological test. Results: The seropositive rate of H. pylori in the patients' group was $71.2\%$ (37/52), and the control group was $65.0\%$ (67/103). The difference between two groups was statistically significant. However the histopathological study showed that the overall detection rate of H. pylori was $61.5\%$ (32/52) in the patients' group and $61.2\%$ (63/103) in the control group; nd this difference was not statistically significant Conclusion: We could confirm that H.pylori infection rate in the gastric cancer resected patients was statistically higher than in the normal healthy persons even in small population. And the detection method for the H. pylori infection by serological test was presumed to be better than that of histopathological test using surgical specimen. Further study for the larger population by well-organized multicenters will be needed.

• Journal of Life Science
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• v.10 no.6
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• pp.630-639
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• 2000

The gastric pathogen Helicobacter pylori(H. pylori) establishes long-term chronic infection that can lead to atrophic gastritis, intestinal metaplasia, and gastric cancer. H. pylori, which express cytotoxic genes is now recohnized as a cause of peptic ulcer and is also a major risk factor for the development of gastric adenocarcinoma. We performed this study 1) to assess the detection rate of H. pylori according to direct investigation of bacteria of gastric biopsy specimen and two serologic tests of GAP test and Helico blot 2.0 system in the symptomatic and non-symptomatic group 2) to evaluate and compare the efficacy of two serologic tests of GAP test and Helico blot 2.0 system for the diagnosis of H. pylori infection. Forty-nine patients were positive for H pylori infection based on direct investigation of bacteria by histology. The detection rates of H. pylori infection based on direct investigation of bacteria by histology. The detection rates of H. phlori were significantly lower in gastric cancer than in other gastroduodenal disease(p<0.05). The concordance of two serologic tests of GAP test and Helico blot 2.0 system is poor. There was no statistically significant difference between the expression rate of CagA and VacA in the symptomatic and non-symptomatic group. Although Helico blot 2.0 system may not displace GAP test, it was a very sensitive serologic test for the diagnosis of H. pylori infection and it was used to detect IgG antibodies to H. pylori-specific antigens, including CagA, VacA and the various urease subunit. Our data suggest that further investigation is needed to determine whether or not the serologic expression of cytotoxic gene may be clinical usefulness of diagnostic methods in the gastroduodenal disease.