Reviewer's report 
 Analysis of antimicrobial susceptibility and virulence factors in Helicobacter pylori clinical Title: 
isolates. 
Authors: 
Anita P.O Godoy ( anita@helicobacter.com.br )
Dr Marcelo L Ribeiro ( marceloribeiro@saofrancisco.edu.br )
Yune H.B Benvengo ( yune@helicobacter.com.br )
Lea Vitiello ( lea@helicobacter.com.br )
Maira C.B Miranda ( maira@helicobacter.com.br )
Sergio Mendonca ( sergiomendonca@saofrancisco.edu.br )
Jose Pedrazzoli Jr ( pedrazzoli@saofrancisco.edu.br )
 1  15 Jul 2003 Version: Date: 
 Dulciene M Queiroz Reviewer: 
 A paper of considerable general medical or scientific interest Level of interest: 
 Accept after discretionary revisions Advice on publication: 
The authors investigated if primary resistance of Brazilian H. pylori isolates to metronidazole, 
clarithromycin, amoxicillin, tetracicline and furazolidone was associated with bacterium virulence markers. In accordance with other studies, no association was seen. The authors have also evaluated the association between the presence of virulence markers of the strains and H. pylori 
related diseases.They demonstrated that vacAs1/cagA-positive strains was positively associated 
with peptic ulcer and negatively associated with GERD. Although there are studies on this subject in 
Brazil, since the country has a continental dimension and differences in geographical distribution of 
H. pylori virulence markers have been demonstrated, the study has important data, but it does not 
add new conceptual information to literature. I recommend this article for publication, after some 
corrections: 
1)Abstract, background and aims, : the authors did not performed correlation test, so they have to 
change "correlation" to "association". 
2)Backgound page 3, line 4: change ...superficial gastritis and peptic ulceration. to ...superficial gastritis, peptic ulcertion and gastric cancer. 3)Methods page 5: subtitle H. PYLORI CULTURE...has to be changed to H. pylori CULTURE... 
4)Statistical analysis: The authors have to clarify how have they constructed the logistic model: What 
were the independent variables? How was the adopted p value in univariate analysis? How did they 
evaluate the fitness of the model? 
5)I strongly agree with the authors' conclusions that more virulent H. pylori 
strains(vacAs1/cagA-positive strains) may protect against GERD. However, in all other sections of 
the manuscript, they showed this result in an inverse way (vacAs2/cagA-negative strains positively 
associated with GERD, with a positive OR).They have to repeat the statistical analysis, ammend the 
text and the last phrase, page 8 has to be better discussed. 
6)Results and discussion, page 10: the authors have to modify the discussion of the last paragraph, 
since they evaluated "primary" resistance and so the patients with duodenal ulcer they evaluated 
were not previously treated. Furthermore, they made conclusions based on treatment failure (cited 
references number 15, 35) more than antimicrobial resistance. 
Competing interests: 
None declared. 
Reviewer's report 
 Analysis of antimicrobial susceptibility and virulence factors in Helicobacter pylori clinical Title: 
isolates. 
Authors: 
Anita P.O Godoy ( anita@helicobacter.com.br )
Dr Marcelo L Ribeiro ( marceloribeiro@saofrancisco.edu.br )
Yune H.B Benvengo ( yune@helicobacter.com.br )
Lea Vitiello ( lea@helicobacter.com.br )
Maira C.B Miranda ( maira@helicobacter.com.br )
Sergio Mendonca ( sergiomendonca@saofrancisco.edu.br )
Jose Pedrazzoli Jr ( pedrazzoli@saofrancisco.edu.br )
 1  15 Jul 2003 Version: Date: 
 Dulciene M Queiroz Reviewer: 
 A paper of considerable general medical or scientific interest Level of interest: 
 Accept after discretionary revisions Advice on publication: 
The authors investigated if primary resistance of Brazilian H. pylori isolates to metronidazole, 
clarithromycin, amoxicillin, tetracicline and furazolidone was associated with bacterium virulence markers. In accordance with other studies, no association was seen. The authors have also evaluated the association between the presence of virulence markers of the strains and H. pylori 
related diseases.They demonstrated that vacAs1/cagA-positive strains was positively associated 
with peptic ulcer and negatively associated with GERD. Although there are studies on this subject in 
Brazil, since the country has a continental dimension and differences in geographical distribution of 
H. pylori virulence markers have been demonstrated, the study has important data, but it does not 
add new conceptual information to literature. I recommend this article for publication, after some 
corrections: 
1)Abstract, background and aims, : the authors did not performed correlation test, so they have to 
change "correlation" to "association". 
2)Backgound page 3, line 4: change ...superficial gastritis and peptic ulceration. to ...superficial gastritis, peptic ulcertion and gastric cancer. 3)Methods page 5: subtitle H. PYLORI CULTURE...has to be changed to H. pylori CULTURE... 
4)Statistical analysis: The authors have to clarify how have they constructed the logistic model: What 
were the independent variables? How was the adopted p value in univariate analysis? How did they 
evaluate the fitness of the model? 
5)I strongly agree with the authors' conclusions that more virulent H. pylori 
strains(vacAs1/cagA-positive strains) may protect against GERD. However, in all other sections of 
the manuscript, they showed this result in an inverse way (vacAs2/cagA-negative strains positively 
associated with GERD, with a positive OR).They have to repeat the statistical analysis, ammend the 
text and the last phrase, page 8 has to be better discussed. 
6)Results and discussion, page 10: the authors have to modify the discussion of the last paragraph, 
since they evaluated "primary" resistance and so the patients with duodenal ulcer they evaluated 
were not previously treated. Furthermore, they made conclusions based on treatment failure (cited 
references number 15, 35) more than antimicrobial resistance. 
Competing interests: 
None declared. 
Please review this paper.
user
Reviewer's report 
 Analysis of antimicrobial susceptibility and virulence factors in Helicobacter pylori clinical Title: 
isolates. 
Authors: 
Anita P.O Godoy ( anita@helicobacter.com.br )
Dr Marcelo L Ribeiro ( marceloribeiro@saofrancisco.edu.br )
Yune H.B Benvengo ( yune@helicobacter.com.br )
Lea Vitiello ( lea@helicobacter.com.br )
Maira C.B Miranda ( maira@helicobacter.com.br )
Sergio Mendonca ( sergiomendonca@saofrancisco.edu.br )
Jose Pedrazzoli Jr ( pedrazzoli@saofrancisco.edu.br )
 1  15 Jul 2003 Version: Date: 
 Dulciene M Queiroz Reviewer: 
 A paper of considerable general medical or scientific interest Level of interest: 
 Accept after discretionary revisions Advice on publication: 
The authors investigated if primary resistance of Brazilian H. pylori isolates to metronidazole, 
clarithromycin, amoxicillin, tetracicline and furazolidone was associated with bacterium virulence markers. In accordance with other studies, no association was seen. The authors have also evaluated the association between the presence of virulence markers of the strains and H. pylori 
related diseases.They demonstrated that vacAs1/cagA-positive strains was positively associated 
with peptic ulcer and negatively associated with GERD. Although there are studies on this subject in 
Brazil, since the country has a continental dimension and differences in geographical distribution of 
H. pylori virulence markers have been demonstrated, the study has important data, but it does not 
add new conceptual information to literature. I recommend this article for publication, after some 
corrections: 
1)Abstract, background and aims, : the authors did not performed correlation test, so they have to 
change "correlation" to "association". 
2)Backgound page 3, line 4: change ...superficial gastritis and peptic ulceration. to ...superficial gastritis, peptic ulcertion and gastric cancer. 3)Methods page 5: subtitle H. PYLORI CULTURE...has to be changed to H. pylori CULTURE... 
4)Statistical analysis: The authors have to clarify how have they constructed the logistic model: What 
were the independent variables? How was the adopted p value in univariate analysis? How did they 
evaluate the fitness of the model? 
5)I strongly agree with the authors' conclusions that more virulent H. pylori 
strains(vacAs1/cagA-positive strains) may protect against GERD. However, in all other sections of 
the manuscript, they showed this result in an inverse way (vacAs2/cagA-negative strains positively 
associated with GERD, with a positive OR).They have to repeat the statistical analysis, ammend the 
text and the last phrase, page 8 has to be better discussed. 
6)Results and discussion, page 10: the authors have to modify the discussion of the last paragraph, 
since they evaluated "primary" resistance and so the patients with duodenal ulcer they evaluated 
were not previously treated. Furthermore, they made conclusions based on treatment failure (cited 
references number 15, 35) more than antimicrobial resistance. 
Competing interests: 
None declared. 
assistant