Review for 10.1186/s12876-020-01301-3 (2020)

Reviewer ’s report  
 
Title: Ischemic colitis induced by indigo naturalis in a patient with ulcerative colitis: A case 
report  
 
Version: 0 Date: 06 Apr 2020  
 
Reviewer: Christian Selinge r 
 
Reviewer's report:  
 
The authors describe a case of ischemic colitis in a 44y old woman with ulcerative colitis. 
They attribute tindigo naturalis as the cause. The article is well writt en and of interest as 
many UC patients use alternative medical therapies and clinicians need to be aware of 
potential risk of these. The main area to address is that the authors need to consider other 
causes of ischemic colitis and describe why they consid er these not be the case.  This 
includes arterothrombotic disease, embolic disease and vasculitis.  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necess ary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Yes 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
 
Yes 
 
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please specify what aspects require further  
assessment in your comments to the editors.  
 
Not relevant to this manuscript  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Acceptable  
 
 
 
 
 
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, funding, or salary from 
an organisation that may in any way gain or lose financially from the publication of 
this manuscript, either now or in the future?  
 
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financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents relating to the content of 
the manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that  
holds  or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in r elation to this paper?  
 
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below.  If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests.  
 
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