Review for 10.1186/s12876-025-04114-4 (2025)

Title: IgG4-related cholangitis – distinguishing from other benign biliary strictures: clinical
features, imaging, and response to treatment: a retrospective study
Version: 1 Date: 29 Apr 2025
Reviewer's report:
The authors retrospectively compared the baseline characteristics, laboratory test results,
imaging findings, and treatment responses between IgG4-related cholangitis (IRC) and other
benign biliary strictures (BBS). They concluded that IRC could be distinguished from other BBS
through specific clinical and imaging features. I have several comments for the authors.
Major
1. The authors used the 2012 Japanese diagnostic criteria for the diagnosis of IRC in this
study (Page9, line296). However, the latest one is the 2020 Japanese diagnostic criteria (J
Hepatobiliary Pancreat Sci. 2021; 28:235-242. doi: 10.1002/jhbp.913.).
2. The authors used the 2020 Amendment of the Japanese consensus guidelines for the
diagnosis of AIP in this study. However, this is the clinical guideline, and not diagnostic
criteria for AIP. The latest Japanese diagnostic criteria for AIP are Japanese Clinical Diagnostic
Criteria for Autoimmune Pancreatitis, 2018: Revision of Japanese Clinical Diagnostic
Criteria for Autoimmune Pancreatitis, 2011 (Pancreas. 2020; 49: e13-e14. doi: 10.1097/
MPA.0000000000001443.)
3. Please show the detailed causes of other BBS such as stone-induced bile duct stricture, chronic
pancreatitis, indeterminate biliary stricture, etc.
4. What was the definition of obstructive jaundice in this study?
5. What is the reason of lower prevalence of ascending cholangitis in IRC compared to other
BBS?
6. The association of AIP was observed in 63% of patients with IRC in this study. As the authors
described in discussion section, this incidence is lower than those of previous reports. It is
challenging to diagnose IRC without AIP in general. This study consists of 9 IRC cases without
AIP. Did all 9 patients meet the 2012 Japanese diagnostic criteria for IgG4-related sclerosing
cholangitis?
7. In table1, the number of patients with AIP was 10. However, in table2, the number of patients
with AIP was 12. Please confirm and revise.
8. IRC sometimes shows multiple biliary strictures. In which part of biliary stricture did the
authors measure as the stricture lengths in these cases?
9. What diameter of biopsy forceps did the authors use in the histological examination?
10. Did the authors use an elastic stain for the evaluation of obliterative phlebitis in this study?
An elastic stain is useful to identify obliterative phlebitis especially in biopsy specimens.
11. Complete response to steroid therapy was observed in 10.5% of patients with other BBS.
What were the final diagnoses of these BBS patients showing good response to steroid therapy?
12. The authors should mention the methos of induction and maintenance steroid therapy in this
study although they mentioned in the discussion section.
13. Please describe the judgement criteria between continuation and discontinuation of stent
placement.
14. Plastic stents were used for a long duration in some cases of IRC group (Figure3). What were
the reasons for long duration of stent placements in these cases? Biliary stricture is commonly
improved in 2-4 weeks after steroid administration in patinets with IRC because IRC usually
show good response to steroid therapy.
Minor
1. Please show the number at risk in Kaplan-Meier analysis (Figure3).