Chiarini A, Calà C, Bonura C, Gullo A, Giuliana G, Peralta S, D'Arpa F, Giammanco A
Department of Sciences for Health Promotion, University of Palermo, Italy.
Eur J Clin Microbiol Infect Dis. 2009 May;28(5):437-46. doi: 10.1007/s10096-008-0644-x. Epub 2008 Oct 29.
In a bacterium like Helicobacter pylori, which is characterized by a recombinant population structure, the associated presence of genes encoding virulence factors might be considered an expression of a selective advantage conferred to strains with certain genotypes and, therefore, a potentially useful tool for predicting the clinical outcome of infections. However, differences in the geographical and ethnic prevalence of the H. pylori virulence-associated genotypes can affect their clinical predictive value and need to be considered in advance. In this study we carried out such an evaluation in a group of patients living in Sicily, the largest and most populous island in the Mediterranean Sea. cagA, vacA, babA2, hopQ, oipA, sabA, and hopZ were the H. pylori virulence-associated genes assayed; their presence, expression status or allelic homologs were detected in H. pylori DNA samples and/or isolated strains, obtained by gastric biopsy from 90 Sicilian patients with chronic gastritis, inactive (n = 37), active (n = 26), or active with peptic ulcer (n = 27). Genotypes cagA (+), vacAs1, vacAm1, babA2 (+), and hopQ I, I/II were identified in 51.8, 80.4, 35.2, 47.3, and 67.7% of the different samples respectively. Only these genotypes were associated with each other and with the active form of chronic gastritis, irrespective of the presence of a peptic ulcer. In our isolates their prevalence was more similar to values observed in the north of Italy and France than to those observed in Spain or other Mediterranean countries that are closer and climatically more similar to western Sicily.
在幽门螺杆菌这样具有重组群体结构特征的细菌中，编码毒力因子的基因的相关存在可能被认为是赋予某些基因型菌株的选择性优势的一种表现，因此是预测感染临床结果的潜在有用工具。然而，幽门螺杆菌毒力相关基因型在地理和种族上的流行差异会影响其临床预测价值，需要提前加以考虑。在本研究中，我们对居住在西西里岛（地中海最大且人口最多的岛屿）的一组患者进行了这样的评估。检测了幽门螺杆菌毒力相关基因cagA、vacA、babA2、hopQ、oipA、sabA和hopZ；通过对90例患有慢性胃炎（非活动期，n = 37；活动期，n = 26；或伴有消化性溃疡的活动期，n = 27）的西西里患者进行胃活检获得的幽门螺杆菌DNA样本和/或分离菌株中，检测了它们的存在、表达状态或等位同源物。在不同样本中，分别有51.8%、80.4%、35.2%、47.3%和67.7%的样本鉴定出cagA(+)、vacAs1、vacAm1、babA2(+)和hopQ I、I/II基因型。只有这些基因型相互关联，并且与慢性胃炎的活动形式相关，无论是否存在消化性溃疡。在我们的分离菌株中，它们的流行率与在意大利北部和法国观察到的值更相似，而与在西班牙或其他与西西里岛西部距离更近且气候更相似的地中海国家观察到的值不同。
