First Department of Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan.
BMC Infect Dis. 2012 Sep 21;12:223. doi: 10.1186/1471-2334-12-223.
Infection with cagA-positive, cagA EPIYA motif ABD type, and vacA s1, m1, and i1 genotype strains of Helicobacter pylori is associated with an exacerbated inflammatory response and increased risk of gastroduodenal diseases. However, it is unclear whether the prevalence and virulence factor genotypes found in Southeast Asia are similar to those in Western countries. Here, we examined the cagA status and prevalence of cagA EPIYA motifs and vacA genotypes among H. pylori strains found in Southeast Asia and examined their association with gastroduodenal disease.
To determine the cagA status, cagA EPIYA motifs, and vacA genotypes of H. pylori, we conducted meta-analyses of 13 previous reports for 1,281 H. pylori strains detected from several Southeast Asian countries.
The respective frequencies of cagA-positive and vacA s1, m1, and i1 genotypes among examined subjects were 93% (1,056/1,133), 98% (1,010/1,033), 58% (581/1,009), and 96% (248/259), respectively. Stratification showed significant variation in the frequencies of cagA status and vacA genotypes among countries and the individual races residing within each respective country. The frequency of the vacA m-region genotype in patients infected with East Asian-type strains differed significantly between the northern and southern areas of Vietnam (p < 0.001). Infection with vacA m1 type or cagA-positive strains was associated with an increased risk of peptic ulcer disease (odds ratio: 1.46, 95%CI: 1.01-2.12, p = 0.046 and 2.83, 1.50-5.34, p = 0.001, respectively) in the examined Southeast Asian populations.
Both Western- and East Asian-type strains of H. pylori are found in Southeast Asia and are predominantly cagA-positive and vacA s1 type. In Southeast Asia, patients infected with vacA m1 type or cagA-positive strains have an increased risk of peptic ulcer disease. Thus, testing for this genotype and the presence of cagA may have clinical usefulness.
感染含有 cagA 阳性、cagA EPIYA 基序 ABD 型和 vacA s1、m1、i1 基因型的幽门螺杆菌与炎症反应加剧和胃十二指肠疾病风险增加有关。然而，目前尚不清楚在东南亚发现的流行率和毒力因子基因型是否与西方国家相似。在这里，我们研究了在东南亚发现的幽门螺杆菌菌株的 cagA 状态和 cagA EPIYA 基序的流行率，并检查了它们与胃十二指肠疾病的关系。
为了确定幽门螺杆菌的 cagA 状态、cagA EPIYA 基序和 vacA 基因型，我们对来自几个东南亚国家的 13 项先前研究报告进行了荟萃分析，共涉及 1281 株幽门螺杆菌菌株。
在所检查的对象中，cagA 阳性和 vacA s1、m1、i1 基因型的频率分别为 93%（1056/1133）、98%（1010/1033）、58%（581/1009）和 96%（248/259）。分层分析显示，cagA 状态和 vacA 基因型在国家之间以及每个国家内的不同种族之间存在显著差异。感染东亚型菌株的患者中 vacA m 区基因型的频率在越南北部和南部地区之间存在显著差异（p<0.001）。感染 vacA m1 型或 cagA 阳性菌株与东南亚人群患消化性溃疡病的风险增加相关（比值比：1.46，95%CI：1.01-2.12，p=0.046 和 2.83，1.50-5.34，p=0.001）。
在东南亚地区既存在西方型也存在东亚型的幽门螺杆菌菌株，且主要为 cagA 阳性和 vacA s1 型。在东南亚地区，感染 vacA m1 型或 cagA 阳性菌株的患者患消化性溃疡病的风险增加。因此，检测这种基因型和 cagA 的存在可能具有临床意义。
