Distribution of cagG gene in Helicobacter pylori isolates from Chinese patients with different gastroduodenal diseases and its clinical and pathological significance.
OBJECTIVE
To determine the distribution of cagG gene of Helicobacter pylori (H pylori) isolates cultured from patients with various digestive diseases and its relationship with gastroduodenal diseases.


METHODS
cagG was amplified by polymerase chain reaction in 145 H pylori isolates cultured from patients with chronic gastritis (n=72), duodenal ulcer (n=48), gastric ulcer (n=17), or gastric and duodenal ulcer (n=8), and the relationship between cagG status and the grade of gastric mucosal inflammation was determined.


RESULTS
cagG was present in 91.7% of the 145 H pylori isolates, with the rates were 90.3%, 93.8%, 88.2% and 100.0%, respectively, in those from patients with chronic gastritis, duodenal ulcer, gastric ulcer, and gastric and duodenal ulcer. There was no significant difference among the four groups (P>0.05). The average grade of gastric mucosal inflammation in the antrum and corpus was 1.819+/-0.325 and 1.768+/-0.312, respectively in cagG positive patients, whereas the average inflammation grade was 1.649+/-0.297, 1.598+/-0.278 respectively in cagG negative cases (P>0.05).


CONCLUSIONS
cagG gene of H pylori was quite conservative, and most H pylori strains in Chinese patients were cagG positive. cagG status was not related to clinical outcome or the degree of gastric mucosal inflammation. Therefore, cagG can not be used as a single marker for discrimination of H pylori strains with respect to a specific digestive disease.
Xu
Can
C
Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China. xucan9@hotmail.com
Li
Zhao-Shen
ZS
Tu
Zhen-Xing
ZX
Xu
Guo-Ming
GM
Gong
Yan-Fang
YF
Man
Xiao-Hua
XH
D000230:Adenocarcinoma / Q000382:microbiology / Q000473:pathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D044466:Asian People; D005260:Female; D005753:Gastric Mucosa / Q000382:microbiology / Q000473:pathology; D005756:Gastritis / Q000382:microbiology* / Q000473:pathology*; D016481:Helicobacter Infections / Q000382:microbiology* / Q000473:pathology*; D016480:Helicobacter pylori / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000382:microbiology / Q000473:pathology; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D013274:Stomach Neoplasms / Q000382:microbiology / Q000473:pathology