Review for 10.1186/1471-230X-11-58 (2011)

Reviewer's report
Title:Low bone mass in microscopic colitis
Version: 1Date:18 July 2010
Reviewer: Kazuhiro Ishiguro
Reviewer's report:
Major Compulsory Revision
1. Is the question posed by authors well defined?
Yes.
2. Are the methods appropriate and well described?
No.
3. Are the data sound?
No. Not impressive.
4. Does the manuscript adhere to the relevant standards for reporting and data
deposition?
N/A.
5. Are the discussion and conclusions well balanced and adequately supported
by data?
No.
6. Are limitaiton of the work clearly stated?
Yes. However, a small number of collected cases can be fatal to this study.
7. Do the authours clearly acknowledge any work upon which they are building,
both published and unpublished?
Yes.
8. Do the title and abstract accurately convey what has been found?
Title, Yes; Abstract, No.
9. Is the writing acceptable?
No.
Abstract
1) There is no solid evidence proving the association between microscopic colitis
and IBDs (UC & CD). Therefore, "Microscopic colitis can be a member of the IBD
group" is not correct.
2) What is "above" the lumbar spine, femoral neck and the radius?
3) Although the authors concluded that low bone mass is frequent, they did not
analyse the incidence of cases with low bone mass.
Introduction
1) There are too many paragraphs.
2) The authors must describe the definition of microscopic colitis with appropriate
references, and also the pathology and pathogenesis of collangenous colitis and
lymphocytic colitis more in detail.
3) Although both collangenous colitis and lymphocytic colitis exhibit minor
findings under colonoscopy and colon X-ray examination (this is why they are
referred to as microscopic colitis), these diseases show different pathological
findings. Therefore, the authors have to present some reasons explaining why
collangenous colitis and lymphocytic colitis could be treated in the same group
for statistical analysis. Otherwise, the authors should treat them in different
groups, for example, collangenous colitis or lymphocytic colitis vs. healthy control
or Crohn's disease, and collangenous colitis vs. lymphocytic colitis.
Methods
1) Why did the authors collect data when all of the patients were symptomless for
six weeks? Why did they not collect data when patients had symptoms,
especially before starting treatments to avoid the effects of the treatments on
bone metabolism?
2) Biological significances of osteocalcin and beta-crosslaps should be described
with some references.
3) It is well known that bone absorption is increased from the middle of night to
early morning, and then decreased. Therefore, blood samples must be taken at a
certain period of the day (early morning is the best) to measure and compare
markers for bone metabolism in the serum. The authors have to make sure that
they took blood samples from patients at the certain timing. This is very critical.
4) Osteocalcin reflects vitamin K content in the bone. The authors must clarify if
patients were taking medicine that could affect vitamin K content in the bone.
5) The authors must present some reasons explaining why low bone mass and
osteoporosis can be defined as a BMD t-score below -1 and below -2.5,
respectively.
Results
1) The authors must present a list showing clinical characteristics of each case,
such as diagnosis, pathology, severity/duration of symptoms, treatments.
2) Figures 1 and 2 should be combined as one figure.
3) Is the value of p on lumbal BMD really correct? The table indicates Lumbal
BMD, HC > MC > CD; there is a statistically significant difference between MC
and CD although there is no difference between HC and CD.
5) The authors must describe statistical methods not only in the Methods section
but also in the table and figure legends to show the appropriate application of
them in each analysis.
6) Which factors affect bone metabolism in MC, duration/severity of diarrhea,
treatments or something else? Statistical analyses were not performed enough,
so that presented results were not impressive.
Discussion
1) There are too many paragraphs.
2) Both markers for bone formation and absorption are increased in MC and CD.
However, bone density is decreased in MC and CD. Why? How is the balance of
bone metabolism disturbed?
Conclusion
1) "Low bone mass was detected above the bones...." What is above the bones?
2) "Taking the epidermiological data...."
Is the aim of this study to show MC and associated osteopenia can be a problem
in patients with chronic diarrhea? If so, the authors should collect cases with
chronic diarrhea and then analyse the incidences of MC and associated
osteopenia.
Writing
Writing must be improved.
For example, abbreviations are repeatedly defined. Results should be described
following appropriate headlines. What is "resp."? Spell it correctively.
Level of interest: An article of limited interest
Quality of written English: Not suitable for publication unless extensively edited
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.