Diagnostic accuracy of serological kits for Helicobacter pylori infection with the same assay system but different antigens in a Japanese patient population

Abstract

Helicobacter pylori infection is thought to be a causal risk factor for gastric carcinoma. Recently, diagnostic accuracy of serological kits for H. pylori infection that were made in Western countries has been reported to be lower when used among Oriental populations. Diagnostic accuracy of two serological kits [HM-CAP and HM-CAP with antigens extracted from clinically isolated Japanese H. pylori strains (J-HM-CAP)] was investigated in 440 samples from a Japanese patient population by using the 13 C-urea breath test as gold standard. According to the original optimal cut-off value, HM-CAP provided 87·5 % sensitivity and 84·8 % specificity with 86·8 % accuracy and J-HM-CAP provided 95·5 % sensitivity and 81·9 % specificity with 92·3 % accuracy. This study suggests that antigens from HM-CAP are satisfactory for examining a Japanese patient population, but that using local antigens improves accuracy.

Association between serum pepsinogens and polymorphismof PTPN11 encoding SHP‐2 among Helicobacter pylori seropositive Japanese

“…In any case, we were certain that the gastric cancer cases used in this study were all infected with H. pylori infection as we utilized 2 serology kits, including the J-HM-CAP ELISA kit (Kyowa Medex), which is sensitive to Japanese H. pylori-infected subjects. 35 Furthermore, we confirmed all gastric cancer cases to be infected with H. pylori by culture and bacteriologic tests (Gram-negative, oxidase, catalase and urease testpositive spiral curved rods) using biopsy specimens before gastric resection. Our finding that all gastric cancer cases had evidence of H. pylori infection is different from other published studies, where the proportion tends to be lower.…”

Antigenic Proteins of Helicobacter pylori of Potential Diagnostic Value

“…It can be expected that if more isolates or more geographical regions are sampled, more subpopulations of H. pylori and populations can be identified (Tay et al, 2009). As mentioned earlier, the diagnostic accuracy of serology kits for detection of H. pylori antibodies may be influenced by strain differences in different regions of the world (Leung et al, 1999;Miwa et al, 2000;Obata et al, 2003). Thus in this study a local isolate of H. pylori from a duodenal ulcer patient and serum samples from patients with various clinical presentations and from three major ethnic groups in Malaysia were used to identify antigens of potential diagnostic value.…”

“…Many ELISA kits for detection of H. pylori antibodies have been reported to provide reliable results when used in Western countries (Evans et al 1989;Crabtree et al 1991;Jensen et al, 1993;Marchildon et al 1996;Meijer et al 1997;Leung et al 1999). However, when these kits were tested in Asian countries, the diagnostic accuracy was significantly lower (Leung et al, 1999;Miwa et al, 2000;Obata et al, 2003). These differences may be due to several reasons, such as strain heterogeneity in different geographic regions (Ohtsuka et al, 1997;Miwa et al, 2002); cross-reactivity with other intestinal pathogens, which vary in different parts of the world ; and varying immunological responses to H. pylori antigens in different patient populations (Khanna et al, 1998).…”

Serum Pepsinogen Values and Helicobacter pylori Status among Control Subjects of a Nested Case-Control Study in the JACC study

“…However, it seems to be impossible to explain the difference in seroprevalence only by the used kits, because differences in sensitivity and specificity between the two kinds of kits are at most 10% and 6%, respectively. 13,14 Another explanation is that prevalence of H. pylori is different between in rural areas and urban areas. 15 Actually, the subjects from a large city with a population of a million people showed similar seroprevalence to our previous study.…”

“…In this study, H. pylori antibody was measured using a domestic kit, which has shown better accuracy than imported kits. 13,14 Our previous study used an imported kit "Pilika-Plate G Helicobacter" which is the same kit as "IgG-GAP." However, it seems to be impossible to explain the difference in seroprevalence only by the used kits, because differences in sensitivity and specificity between the two kinds of kits are at most 10% and 6%, respectively.…”