Differences in virulence markers between Helicobacter pylori strains from the Brazilian Amazon region

Introduction This study compares virulence markers of Helicobacter pylori isolated from patients in 2 cities in the Brazilian Amazon. Methods The study analyzed 168 patients with chronic gastritis from Belém and 151 from Bragança, State of Pará, Brazil. Levels of bacterial DNA associated with cagA and vacA alleles were checked by PCR, and hematoxylin-eosin staining was used for histologic diagnosis. Results In Bragança 87% of patients were genotype s1m1 cagA-positive (s1m1 cagA+), compared with 76% in Belém. In samples from patients in both cities, there was an association between s1m1 cagA+ strains and gastric mucosal damage. Conclusions Both cities have a high frequency of s1m1 cagA+ strains of H. pylori.

引言 本研究对比分析了从巴西亚马逊地区两座城市的患者体内分离的幽门螺杆菌（Helicobacter pylori）毒力标志物。
方法 本研究共纳入巴西帕拉州贝伦市的168例慢性胃炎患者与布拉干萨市的151例慢性胃炎患者。采用聚合酶链反应（PCR）检测与cagA基因、vacA等位基因相关的细菌DNA水平，并通过苏木精-伊红染色法开展组织病理学诊断。
结果 布拉干萨市有87%的患者感染s1m1 cagA阳性（s1m1 cagA+）基因型菌株，而贝伦市该比例为76%。两座城市的患者样本均显示，s1m1 cagA阳性菌株与胃黏膜损伤存在关联。
结论 两座城市均存在高频率的幽门螺杆菌s1m1 cagA阳性菌株流行。