Helicobacter pylori strains and histologically-related lesions affect the outcome of triple eradication therapy: a study from southern Italy


Correspondence to: Dr F. Russo, Laboratory of Biochemistry, IRCCS ‘Saverio de Bellis’, 70013 Castellana Grotte, Bari, Italy. E-mail: irccsbiochimica@libero.it


Background : Certain evidence suggests that Helicobacter pylori strains expressing genes for cytotoxin production show a higher sensitivity than non-cytotoxic organisms to eradication treatment. No data are available on the involvement of bacterium-related lesions in different therapeutic outcomes.

Aims : (i) To investigate whether differences in eradication rates may be related to the different expression of virulent strains (cagA, vacA, iceA) in patients undergoing proton pump inhibitor-based triple therapy, and (ii) to evaluate whether therapeutic outcome may be affected by bacterium-induced gastric lesions.

Methods : One hundred and ten H. pylori-positive subjects were enrolled. H. pylori was genotyped by polymerase chain reaction. Treatment consisted of lansoprazole–amoxicillin–clarithromycin, twice daily for 1 week. Eradication was checked by urea breath test.

Results : The eradication rate was 70%, and the absence of cagA was associated with unsuccessful treatment. No difference between the groups with successful and unsuccessful eradication was found with regard to vacA and iceA. Lympho-epithelial lesions and fibrosis were associated with unsuccessful treatment.

Conclusions : The present data confirm the importance of cagA (but not vacA and iceA) as a predictor of successful eradication. When fibrosis and lympho-epithelial lesions are present, therapy appears to be less effective. Therefore, these histological features may be involved in an unsuccessful therapeutic outcome.