Review for 10.1186/s12876-020-01226-x (2020)

Reviewer ’s report  
 
Title: Endoscopic stent placement above the sphincter of Oddi for biliary strictures after living 
donor liver transplantation.  
 
Version: 2 Date: 15 Jan 2020  
 
Reviewer: Zhijun Zhu  
 
Reviewer's report:  
 
The manuscript entitled "Endoscopic stent placement above the sphincter of Oddi for biliary 
strictures after living donor liver transpl antation" reported 98 ERC sessions for 16 LDLT 
recipients with biliary strictures. The effects and complications of outside and inside stent 
placement were compared. However the number of cases were small and the baseline 
characteristics of biliary strictu res were not showed, both of which compromised the reliability 
of conclusion. Therefore, a major revise is needed, before it is considered for publication.  
 
 
Questions and recommendations:  
 
1. Baseline data, especially characteristics of biliary strictures, s hould be supplemented.  
 
2. The rationale by which outside and inside stent were selected should be elucidated and well 
discussed.  
 
3. Was the schedule of ERC were reasonable? Can stent migration be found timely according to 
this schedule? The frequency or i ncidence of symptoms such as fever, jaundice should be 
described.  
 
4. Stent occlusion should be suspected when jaundice or cholangitis recurred with the stent 
across the biliary stricture. However it should be diagnose by ERC.  
 
5. Were endoscopic sphinctero tomy made in these cases? And were there any patients suffered 
from reflux cholangitis after the inside or outside stent treatments?  
 
6. The "success rate of 88%" should be corrected as "be placed successfully in 88% patients".  
 
7. As 2 cases of biliary anas tomotic biliary stricture were not treat by ERC, the total rate of 
patient improved by ERC among all the patient indicated for ERC should be calculated (7/16). 
The indication of biliary stricture for ERC should be clarified.  
 
8. Were the period of follow -up enough to conclude "no patient suffering from recurrence after 
removal of plastic stent"?  
 
9. Was metallic stent ever used for anastomotic biliary stricture in LDLT?  
10. In the conclusion, "The stent patency period was significantly longer for inside sten t than for 
outside stent placement, excluding stent migration in our study", why stent migration was 
excluded?  
 
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 necessary controls?  
If not, please specify which controls are r equired 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 manus cript or would you recommend an 
additional statistical review?  
If an additional statistical review is recommended, please speci fy what aspects require further 
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate the qua lity 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 salar y 
from an organisation that may in any way gain or lose financial ly from the 
publication of this manuscript, either now or in the future?  
 
2.  Do you hold any stocks or shares in an organisation t hat may in any way gain or 
lose financially from the publicati on 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 relation to this paper?  
 
If you can answer no to all of the above, write 'I decla re that I have  no competing interests' 
below. If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests  
 
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