Review for 10.1186/s12876-023-02836-x (2023)

Title: Endoscopic injection sclerotherapy for treating recurrent bleeding of small bowel
angioectasias
Version: 0 Date: 24 Nov 2022
Reviewer's report:
This study is a retrospective and single-center case-control study in China to evaluate
effectiveness and safety of endoscopic injection sclerotherapy (EIS) for treating recurrent
bleeding of small bowel angioectasias (SBAs). The authors concluded that EIS could be regard
as the preferred endoscopic therapy for SBAs. This topic is interesting, but I have some
comments as indicated below.
Major comments:
1) There seems to be a bias between the control and EIS group. Especially, I am anxious
about the significant difference of age between control and EIS groups. As patients grow old,
complications might increase. There is a possibility that the difference of age affects rebleeding
rates. Could you please explain this point?
2) Active bleeding observed in the control group chose conservative treatment. In the EIS
group, the re-bleeding rate may have decreased because the responsible lesion was identified
and treatment intervention was possible. Is there a rationale for deciding which of treatments
to choose? Because the choice can be a serious bias, the authors should have some kind of
indication. In addition, I want to know the characteristics of lesions in the control and EIS group
(e.g., type of SBAs, number of lesions, number of treated lesions, presence of active bleeding
etc.).
3) This study included patients with bleeding at least twice in 12 months before admission. It
should be mentioned how to deal with the first bleeding. The authors also described that the
re-bleeding rate of patients underwent EIS treatment was 22.58% (7/31). Please describe the
treatment of re-bleeding in these 7 cases.
4) Let me know the progress during hospitalization? In control group, did the patients stayed
longer in the hospital because re-bleeding occurred or other events?
5) There was comparison between EIS and APC in the discussion. It should also mention the
comparison between EIS and clip in the discussion.
6) Reference 12 is a report of the efficacy of EIS for hemangioma and is ineligible for comparison
with SBA in this paper. The authors should use the literature describing the effectiveness of
EIS for SBA.
7) As can be said throughout, this content shows the effectiveness of the EIS, but it does not
compare APC. Some representations could be misleading as better than APC, such as “the
rate of re-bleeding in our study was far lower than that of APC reported by Romagnuolo, et
al. [7] and Sakai, et al. [22], further indicating effectiveness of EIS to treat SBAs”(page10)
and “In EIS treatment, local submucosal injection with sclerosing agent did not cause
small bowel perforation in any case. In contrast, APC is a technique of noncontact thermal
therapy; and the close contact with intestinal wall of thermal probe could lead to perforation,
which is a life-threatening adverse event for those patients with advanced age and multiple
complications.” (Page 11). I would suggest modifying the sentence.
Minor comments:
1) In table 1, “length of stay” seems to be a result rather than patients characteristics. It may
indicate that treatment intervention with EIS significantly shortened the length of stay.
2) I point out a spelling mistake. In “Introduction” of line 7, “small angioectasias (SBAs)” should
be corrected to “small bowel angioectasias (SBAs)”.
3) “RBC transfusion before admission, multiple lesions (# 3) and EIS treatment were
significantly associated with re-bleeding in patients with SBAs (all P <0.05, Table 4)..” There
is one more period in this sentence.