Busolo F, Bertollo G, Bordignon G, Madia D, Camposampiero D
Institute of Microbiology of Padua University, Faculty of Medicine, Italy.
Diagn Microbiol Infect Dis. 1998 Aug;31(4):531-6. doi: 10.1016/s0732-8893(98)00055-8.
Polymerase chain reaction and cytotoxin assays were performed to identify as Helicobacter pylori type I (cagA+/tox+) or type II (cagA-/tox-) 56 (59.6%) strains from 94 patients. Of these patients 64 were affected by nonulcer dyspepsia (NUD), 10 by gastric ulcer (GU), 19 by duodenal ulcer (DU), and 1 by both GU and DU. H. pylori strains were tested for cagA using two sets of primers; target sequences were detected in 40-42/56 (71.4-75%) depending on the set of primers used, while cytotoxin-producing strains (tox +) were 26/56 (46.4%). Tox+ strains were isolated in 13/32 (40.6%), 2/7 (28.6%), and 11/17 (64.7%) in NUD, GU, and DU patients, respectively. However, the different percentage between cagA+ strains from NUD patients (13/32; 40.6%) and patients with ulcerative diseases (13/23; 54.2%) is not statistically significant (p = 0.462). Because the two sets of primers employed for amplification of cagA target sequences give different results, we concluded that cagA alone could not be taken as predictive factor for severity of gastroduodenal disease. It has been found that H. pylori type I is associated with duodenal ulcer disease.
对94例患者的菌株进行聚合酶链反应和细胞毒素检测，以鉴定幽门螺杆菌I型（cagA+/tox+）或II型（cagA−/tox−）。其中，64例患者患有非溃疡性消化不良（NUD），10例患有胃溃疡（GU），19例患有十二指肠溃疡（DU），1例同时患有GU和DU。使用两组引物检测幽门螺杆菌菌株的cagA；根据所用引物组的不同，在40 - 42/56（71.4 - 75%）的菌株中检测到目标序列，而产生细胞毒素的菌株（tox+）为26/56（46.4%）。在NUD、GU和DU患者中，tox+菌株的分离率分别为13/32（40.6%）、2/7（28.6%）和11/17（64.7%）。然而，NUD患者（13/32；40.6%）和溃疡性疾病患者（13/23；54.2%）中cagA+菌株的不同百分比无统计学意义（p = 0.462）。由于用于扩增cagA目标序列的两组引物给出了不同的结果，我们得出结论，单独的cagA不能作为胃十二指肠疾病严重程度的预测因素。已发现幽门螺杆菌I型与十二指肠溃疡疾病有关。
