Review for 10.1186/s12876-021-01905-3 (2021)

Reviewer’s report
Title: 
SARS-CoV-2 identified by transmission electron microscopy in
lymphoproliferative and ischemic intestinal lesions of COVID-19 patients with
acute abdominal pain: two case reports
Version: 
1 
Date: 
17 Jun 2021
Reviewer's report:
"PEER REVIEWER ASSESSMENTS: 
OBJECTIVE - Full research articles: is there a clear objective that addresses one
or several testable research questions? (Brief or other article types: is there a
clear objective?)
Yes - there is a clear objective
DESIGN - Is the current approach (including controls and analysis protocols)
appropriate for the objective?
No - there are major issues
EXECUTION - Are the experiments and analyses performed with sufficient
technical rigor to allow confidence in the results?
Yes - experiments and analyses were performed appropriately
STATISTICS - Is the use of statistics in the manuscript appropriate?
N/A - there are no statistics in this study
INTERPRETATION - Is the current interpretation/discussion of the results
reasonable and not overstated?
No - there are major issues
OVERALL MANUSCRIPT POTENTIAL - Has the author addressed your
concerns sufficiently for you to now recommend the work as a technically sound
contribution? If not, can further revisions be made to make the work technically
sound?
Yes - current version is technically sound
PEER REVIEWER COMMENTS: 
GENERAL COMMENTS: This manuscript is well presented and assembled.
The topic of SarsCov2 is really hot at present and the possible involvement of
intestine is of interest. The description of the two case reports is detailed, and it
appears that the authors have followed the Editor's and reviewers' suggestions.
The identification of SarsCov2 particles is performed applying transmission
electron microscopy (TEM) 
but the confirmation of the results shown is not
performed with the identification of virus RNA and expression of viral proteins.
This is a strong limitation for the exact interpretation of the findings reported.
Furthermore, the identification of the presence of the virus is not determined in
the patients' stool.
REQUESTED REVISIONS: 
The lack of the identification of the virus with complementary techniques beside
the TEM is a strong limitation of this work. The Authors have replied very well
to the reviewers' queries and I agree with some interpretation of the result, but I
would advise to be more cautious to state that the infection is due to the
SarCov2. Indeed, if I am not wrong, the data 
shown indicate the presence of a
coronavirus in some patients infected with SarsCov2 at another place."
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