Bindayna Khalid Mubarak, Al Mahmeed Ali
Departments of Microbiology, Immunology and Infectious Diseases, College of Medicine and Medical Sciences, Arabian Gulf University, P.O. Box 26671, Manama, Kingdom of Bahrain.
Indian J Gastroenterol. 2009 Sep-Oct;28(5):175-9. doi: 10.1007/s12664-009-0069-1. Epub 2010 Jan 27.
The vacuolating cytotoxin and the cytotoxinassociated protein, encoded by vacA and cagA, respectively, are important virulence determinants of Helicobacter pylori.
The aim of this study was to perform vacA genotyping and evaluate its association with cagA genotype and clinical outcome.
One hundred and twenty H. pylori strains were isolated from dyspeptic patients (29 with peptic ulcer, 91 with non-ulcer dyspepsia). Genotype was determined by PCR.
Seventy-nine (66%) of 120 strains had the vacA signal sequence genotype s1 and 41 (34%) had the type s2. The vacA middle-region types m1 and m2 were detected in 56 (47%) and 64 (53%) strains, respectively. The combinations s1-m1 (n=56 [47%] and s2-m2 (41 [34%]) occurred more frequently than s1-m2 (23 [19.2%]; p=0.001). No strain with the combination s2-m1 was found. All patients with peptic ulcers harbored type s1 strains compared to 75 (82.4%) of 91 patients with non-ulcer dyspepsia (p=0.01). The vacA genotype s1 was associated with the presence of cagA (p <0.0001). The cagA gene was detectable in 38 (31.6%) of 120 isolates and present in all 29 patients with ulcer compared to nine of 91 with non-ulcer dyspepsia (p <0.001).
Helicobacter pylori strains of vacA type s1 and the combination of s1-m1 were associated with peptic ulceration and the presence of cagA gene.
空泡毒素和细胞毒素相关蛋白分别由vacA和cagA编码，是幽门螺杆菌重要的毒力决定因素。
本研究旨在进行vacA基因分型，并评估其与cagA基因型及临床结局的相关性。
从消化不良患者中分离出120株幽门螺杆菌菌株（29例患有消化性溃疡，91例患有非溃疡性消化不良）。通过聚合酶链反应确定基因型。
120株菌株中，79株（66%）具有vacA信号序列基因型s1，41株（34%）具有s2型。分别在56株（47%）和64株（53%）菌株中检测到vacA中间区域类型m1和m2。s1-m1组合（n = 56 [47%]）和s2-m2组合（41 [34%]）比s1-m2组合（23 [19.2%]）出现得更频繁（p = 0.001）。未发现s2-m1组合的菌株。所有消化性溃疡患者均携带s1型菌株，相比之下，91例非溃疡性消化不良患者中有75例（82.4%）携带s1型菌株（p = 0.01）。vacA基因型s1与cagA的存在相关（p < 0.0001）。在120株分离株中有38株（31.6%）可检测到cagA基因，所有29例溃疡患者均携带该基因，相比之下，91例非溃疡性消化不良患者中有9例携带（p < 0.001）。
vacA s1型幽门螺杆菌菌株以及s1-m1组合与消化性溃疡和cagA基因的存在相关。
