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  1 Jul 2003 Version: Date: 
 Leen-Jan van Doorn Reviewer: 
 A paper whose findings are important to those with closely related research Level of interest: 
interests 
 Accept after discretionary revisions Advice on publication: 
This paper is a nice and comprehensive study on H. pylori isolates in Brazil. The experimental 
design and results are straightforward. Genotyping of the virulence-associated genes has been performed adequately and the results confirm earlier findings. 
I have little comments, except on the high resistance rates observed to amoxicillin and tetracyclin. 
These rates are so high, that I would urge the authors to provide more evidence since they can have 
an important impact on treatment efficacy in the near future in Brazil. Therefore, I would like to 
further support their observations. The following 3 approaches could be used. 
1. Did the authors try to obtain resistant reference strains for each antibiotic resistance. This would 
be very helpful to demonstrate the accuracy of the MIC determinations. 2. Alternative techniques to the agar dilution method could be used, such as the E-test. 3. Since the authors are obviously very capable in genotyping H. pylori strains, I would suggest that 
they analyse some of the resistant strains for the presence of specific mutations. For instance, it 
would be easy to assess the presence of the 23S rDNA mutations in clarithromycin resistant strains. 
Also, some mutations have been described for other resistances. It would be valuable information to 
add to this paper. 
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  1 Jul 2003 Version: Date: 
 Leen-Jan van Doorn Reviewer: 
 A paper whose findings are important to those with closely related research Level of interest: 
interests 
 Accept after discretionary revisions Advice on publication: 
This paper is a nice and comprehensive study on H. pylori isolates in Brazil. The experimental 
design and results are straightforward. Genotyping of the virulence-associated genes has been performed adequately and the results confirm earlier findings. 
I have little comments, except on the high resistance rates observed to amoxicillin and tetracyclin. 
These rates are so high, that I would urge the authors to provide more evidence since they can have 
an important impact on treatment efficacy in the near future in Brazil. Therefore, I would like to 
further support their observations. The following 3 approaches could be used. 
1. Did the authors try to obtain resistant reference strains for each antibiotic resistance. This would 
be very helpful to demonstrate the accuracy of the MIC determinations. 2. Alternative techniques to the agar dilution method could be used, such as the E-test. 3. Since the authors are obviously very capable in genotyping H. pylori strains, I would suggest that 
they analyse some of the resistant strains for the presence of specific mutations. For instance, it 
would be easy to assess the presence of the 23S rDNA mutations in clarithromycin resistant strains. 
Also, some mutations have been described for other resistances. It would be valuable information to 
add to this paper. 
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  1 Jul 2003 Version: Date: 
 Leen-Jan van Doorn Reviewer: 
 A paper whose findings are important to those with closely related research Level of interest: 
interests 
 Accept after discretionary revisions Advice on publication: 
This paper is a nice and comprehensive study on H. pylori isolates in Brazil. The experimental 
design and results are straightforward. Genotyping of the virulence-associated genes has been performed adequately and the results confirm earlier findings. 
I have little comments, except on the high resistance rates observed to amoxicillin and tetracyclin. 
These rates are so high, that I would urge the authors to provide more evidence since they can have 
an important impact on treatment efficacy in the near future in Brazil. Therefore, I would like to 
further support their observations. The following 3 approaches could be used. 
1. Did the authors try to obtain resistant reference strains for each antibiotic resistance. This would 
be very helpful to demonstrate the accuracy of the MIC determinations. 2. Alternative techniques to the agar dilution method could be used, such as the E-test. 3. Since the authors are obviously very capable in genotyping H. pylori strains, I would suggest that 
they analyse some of the resistant strains for the presence of specific mutations. For instance, it 
would be easy to assess the presence of the 23S rDNA mutations in clarithromycin resistant strains. 
Also, some mutations have been described for other resistances. It would be valuable information to 
add to this paper. 
Competing interests: 
None declared. 
assistant