Review for 10.1186/1471-230X-11-96 (2011)

Reviewer's report
Title:The Frequency Of Microscopic And Focal Active Colitis In Patients With
Irritable Bowel Syndrome
Version: 2Date:18 May 2011
Reviewer: Darren Brenner
Reviewer's report:
Dear Authors:
Thank you for the submission of your paper entitled: The Frequency of
Microscopic and Focal Active Colitis in Patients with Irritable Bowel Syndrome.
This is a very interesting and improtant topic which requires further study. The
following are my comments regarding yoru manuscript.
-->Major Compulsory Revisions
1. Could you please comment whether the study was performed prospectively or
retrospectively. I could not find this information.
2. Why did you chose to use Rome II Criteria given that collection of data was
initiated in 2007 (after Rome III was released)?
3. The controls that were chosen for comparison turned out to be neither
matched for age nor sex. There were significant differences between the IBS and
control groups and most importantly, the control group was significantly older.
Given that you are making a comparison between IBS and a disorder which is
age based and has a higher prevalence in females (collagenous colitis), it
appears that you tried to statistically account for these differences using logisitic
regression? I do not belive this can be done as the comparison group for a
prevalence study such as this one should be matched for at least age.
4. Did you control for other factors associated with the development of
Microscopic Colitis (Meds/Tobacco use..)
5. Backgroup section: last sentence. I am not sure this is the exact purpose of
the study. The goal was to define the prevalence of histopatholoigc changes
consistent with current definitions of MC and FAC in a cohort of patients meeting
IBS criteria. Subsets of IBS patients have been shown to have inflammatory
changes in colonic biopsies which have not been completely elucidated. There
may be some overlap.
6. Why was the celiac assessment performed using Gliaden antibodies when
USA and European Celiac Societies recommend tissue tranglutaminase. This is
important given the increased prevalence of celiac in patients with either IBS or
microscopic colitis.
7. The IBS population used in this study was only 55% female. Is this typical of
the IBS piopulation in Turkey?
8. As far as I can tell the histologic definition you used for focal active colitis was
never described. Please add this to the methods section.
9. Results section: last paragraph: You comment that LC differed among IBS
subtypes (p<0.01) was this for IBS-D vs M and C or D+M vs C. Please describe
where the significant differences are b/t groups. This also needs to be made
clear in Figure II.
10. Discussion: 2nd sentence. This statement needs a citation as does the study
by Chey et al which is not cited in the bibliography.
11. Discussion: Paragraph starting with "MC is a rare disease" you comment that
Tuncer et al., found a prevalence of MC in 23.3% of IBS patients but the study
actually looked at patients with symptoms consistent with IBS. This should be
clarified.
12. Discussion section: You must discuss the limitations of your study and
including #3 above.
13. Discussion section: Paragraph on FAC. I am not sure of the take home
message. Are you stating that all patients should be biopsied b/c there may be
microscopic changes. Please clarify further.
14. Conclusion; You comment asy ou did in the abstract that MC can be
identified in pts w/IBS-D and women but I did not see any stats in the article
regarding the increased prevalence in women. Please comment or add this data.
15. Table I: Based on the currently available data, this list appeares extremely
restricture. Can you comment how you chose these factors to include as "alarm
features."
-->Minor Essential Revisions
1. Material and Methods: 2nd paragrapg 1st sentence change "Roma II" to
"Rome II"
2. Disucssion paragraph starting with "MC" I wouldn't use the shorthand at the
beginning of a paragraph. Spell out Microscopic Colitis.
3. Conclusion: Instead of stating the "It may be reasonable" consider changing to
"It appears reasonable."
4. Tables II and III and Figure I: please change "lymphositic" to "lymphocytic"
-->Discretionary revisions
1. In the conclusion portion of the abstract: you comment upon the fact that MC is
more common in older women. I would consider adding some data in the results
section to validate this finding.
2. Background Section:
1st sentence: consdier changing "disease" to "disorder"
2nd and 3rd sentences: I would consider restructuring these sentences. You
could consider something like the following: This disorder is characterized by
abdominal pain ro dicomfort associated with altered bowel habits.
2nd paragraph sentence starting with collagenous colitis: I would remove this
removing this statement as it comes before your differentiation of MC as 2
subtypes. I think the explanation of the 2 subtypes as you have explained them is
sufficient.
3. Results section paragraph starting with "The control group subjects did not
have..." Consider removing this paragraph as it is likely unnecessary.
4. Results section sentence beginning with "However, lymphocytic colitis
differed..." This flows better if placed before your disussion on FAC as it directly
related to the MC portion of the findings. Then the final sentence regarding the
incidence of FAC can be added to the paragraph ending with "FAC was found in
6.6%...)
5. Discussion: 2 paragraphs starting with "A retropective study
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare I have no competing interests.