Title: Biliary obstruction and pancreatitis after duodenal stent placement in the descending
duodenum: a retrospective study
Version: 2 Date: 24 Mar 2022
Reviewer's report:
This is a clinically interesting study investigating duodenal stent-related risk factors for
cholangitis and/or pancreatitis. However, there are several issues in this paper that need to be
reconsidered.
1. The authors considered that the risk factors for cholangitis/pancreatitis obtained from this
study might mainly result in the orifice obstruction of duodenal major papilla, which may
increase intraductal pressure of biliary tract and/or pancreatic ducts.
A) In pancreatitis, I agree with the mechanism. However, it is questionable whether a similar
mechanism could be the cause in cholangitis. The diagnosis of cholangitis was described as
"fever lasting >24 hours with cholestasis”. There was no description whether biliary infection
was presented or not, so the details are not available. Although presumably aseptic cholangitis
was not common in this cohort, the fever was caused by infection combined with cholestasis.
Increased intraductal pressure of biliary tract may cause cholestasis, resulting in pain and/or
jaundice, but not always accompanied by fever. Thus, the question arises against combining
cholangitis and pancreatitis together and considering risk factors.
B) There are also significant clinical differences between cholangitis and pancreatitis, including
drainage methods and outcomes in severe cases. It was mentioned as limitation of this study that
there was a problem with the number of cases, but it seems that there is not much difference
between 11 cases of cholangitis and/or pancreatitis and 9 cases of cholangitis. It would be of
more clinical value to examine risk factors for each group, separately.
C) When considering cholangitis, it would be more meaningful if not only risk factors for
cholestasis but also for biliary infection (e.g., inflammatory findings prior to duodenal stent
placement) could be taken into account.
2. Were all cases of pancreatitis cancers other than pancreatic cancer? Pancreatic cancer located
in groove lesion or uncinate process are not always accompanied by obstruction of the MPD,
and how is the evaluation of dilated MPD handled in pancreatic cancer cases?
#.  In which primary diseases was tumor invasion to the major duodenal papilla most frequently
observed?
Title: Biliary obstruction and pancreatitis after duodenal stent placement in the descending
duodenum: a retrospective study
Version: 2 Date: 24 Mar 2022
Reviewer's report:
This is a clinically interesting study investigating duodenal stent-related risk factors for
cholangitis and/or pancreatitis. However, there are several issues in this paper that need to be
reconsidered.
1. The authors considered that the risk factors for cholangitis/pancreatitis obtained from this
study might mainly result in the orifice obstruction of duodenal major papilla, which may
increase intraductal pressure of biliary tract and/or pancreatic ducts.
A) In pancreatitis, I agree with the mechanism. However, it is questionable whether a similar
mechanism could be the cause in cholangitis. The diagnosis of cholangitis was described as
"fever lasting >24 hours with cholestasis”. There was no description whether biliary infection
was presented or not, so the details are not available. Although presumably aseptic cholangitis
was not common in this cohort, the fever was caused by infection combined with cholestasis.
Increased intraductal pressure of biliary tract may cause cholestasis, resulting in pain and/or
jaundice, but not always accompanied by fever. Thus, the question arises against combining
cholangitis and pancreatitis together and considering risk factors.
B) There are also significant clinical differences between cholangitis and pancreatitis, including
drainage methods and outcomes in severe cases. It was mentioned as limitation of this study that
there was a problem with the number of cases, but it seems that there is not much difference
between 11 cases of cholangitis and/or pancreatitis and 9 cases of cholangitis. It would be of
more clinical value to examine risk factors for each group, separately.
C) When considering cholangitis, it would be more meaningful if not only risk factors for
cholestasis but also for biliary infection (e.g., inflammatory findings prior to duodenal stent
placement) could be taken into account.
2. Were all cases of pancreatitis cancers other than pancreatic cancer? Pancreatic cancer located
in groove lesion or uncinate process are not always accompanied by obstruction of the MPD,
and how is the evaluation of dilated MPD handled in pancreatic cancer cases?
#.  In which primary diseases was tumor invasion to the major duodenal papilla most frequently
observed?
Please review this paper.
user
Title: Biliary obstruction and pancreatitis after duodenal stent placement in the descending
duodenum: a retrospective study
Version: 2 Date: 24 Mar 2022
Reviewer's report:
This is a clinically interesting study investigating duodenal stent-related risk factors for
cholangitis and/or pancreatitis. However, there are several issues in this paper that need to be
reconsidered.
1. The authors considered that the risk factors for cholangitis/pancreatitis obtained from this
study might mainly result in the orifice obstruction of duodenal major papilla, which may
increase intraductal pressure of biliary tract and/or pancreatic ducts.
A) In pancreatitis, I agree with the mechanism. However, it is questionable whether a similar
mechanism could be the cause in cholangitis. The diagnosis of cholangitis was described as
"fever lasting >24 hours with cholestasis”. There was no description whether biliary infection
was presented or not, so the details are not available. Although presumably aseptic cholangitis
was not common in this cohort, the fever was caused by infection combined with cholestasis.
Increased intraductal pressure of biliary tract may cause cholestasis, resulting in pain and/or
jaundice, but not always accompanied by fever. Thus, the question arises against combining
cholangitis and pancreatitis together and considering risk factors.
B) There are also significant clinical differences between cholangitis and pancreatitis, including
drainage methods and outcomes in severe cases. It was mentioned as limitation of this study that
there was a problem with the number of cases, but it seems that there is not much difference
between 11 cases of cholangitis and/or pancreatitis and 9 cases of cholangitis. It would be of
more clinical value to examine risk factors for each group, separately.
C) When considering cholangitis, it would be more meaningful if not only risk factors for
cholestasis but also for biliary infection (e.g., inflammatory findings prior to duodenal stent
placement) could be taken into account.
2. Were all cases of pancreatitis cancers other than pancreatic cancer? Pancreatic cancer located
in groove lesion or uncinate process are not always accompanied by obstruction of the MPD,
and how is the evaluation of dilated MPD handled in pancreatic cancer cases?
#.  In which primary diseases was tumor invasion to the major duodenal papilla most frequently
observed?
assistant