Korean J Gastroenterol.  2003 Feb;41(2):101-110.

The Role of the Helicobacter pylori Virulence Factor Gene Subtype and IS605 in Duodenal Ulcer

• Keum DJ
• Han SY
• Kim KJ
• Jee SR
• Lee JH
• Choi SR
• Shin WW
• Kim JM
• Hong SH
• Kim DH

Abstract

BACKGROUND/AIMS: The Helicobacter pylori (H. pylori) cagA, vacA, and iceA are considered to be important virulence factors that have been implicated in the development of duodenal ulcers. It was reported that the presence of IS605 elements might be responsible for rearrangements and partial or total deletion of the cag pathogenicity island (PAI), which might change the virulence of cag PAI. This study evaluated the relationship between H. pylori virulence factors and duodenal ulcer. METHODS: Among 38 patients with duodenal ulcer and 66 controls, we confirmed H. pylori infection in 57 subjects (duodenal ulcer 27, control 30) by PCR using ureC gene and 16S rRNA. For H. pylori isolates obtained from the 57 H. pylori-infected subjects, PCR was performed to examine the cagA, vacA, iceA, and IS605 genotypes. RESULTS: The positive rate of H. pylori in duodenal ulcer group (81.6%) was significantly higher than that of controls (48.5%, p<0.001). The positive rate of cagA in duodenal ulcer group (88.9%) was also significantly higher than that in controls (66.7%, p=0.046). The positive rates of IS605 in all genomes were 59.3% in duodenal ulcer group and 36.7% in controls (p>0.05). In duodenal ulcer group, the positive rate of cagA+/IS605+ was about two times higher than that in controls (51.9% vs. 26.7%) and the positive rate of cagA-/IS605- was lower than that in controls (3.7% vs. 23.3%, p=0.033). CONCLUSIONS: We could confirm the relationship between cagA+ and duodenal ulcer. However, other virulence factors were not related significantly with duodenal ulcer. Further studies are needed to examine the specificity of H. pylori strains in Korea.

Keyword

Helicobacter pylori; cagA; vacA; iceA; IS605