Review for 10.1186/s12876-025-03975-z (2025)

Title: Red cell distribution width as a potential new biomarker to predict the clinical severity
of acute diverticulitis
Version: 1 Date: 24 Feb 2025
Reviewer:  Anwar Ashraf Abouelnasr
Reviewer's report:
Dear Authors, please address the following points below
-A brief mention of how RDW might be linked to the inflammatory processes in diverticulitis
could help provide context. For example, RDW could be reflective of the body's response to
systemic inflammation or oxidative stress.
-Since RDW’s association with gastrointestinal diseases is mentioned but not detailed, providing
examples or citations from relevant studies could further bolster the rationale.
-Although the cross-sectional design is suitable for exploring associations, a longitudinal follow-
up would help determine the prognostic value of RDW over time. This would address whether
RDW can predict long-term outcomes or recurrent episodes of diverticulitis.
-The mention of using Spearman correlation coefficients is good, but further clarification on
why it is used specifically (for non-parametric relationships) might enhance the clarity of the
methodology. A mention of how missing data was handled would also be useful.
-It would be helpful to elaborate on the potential confounders that could affect RDW levels, such
as iron deficiency or chronic diseases (besides diverticulitis), which could impact the results.
-While the study highlights RDW's predictive capabilities, it would be beneficial to explore
potential mechanisms that explain RDW’s association with diverticulitis severity. For example,
could the anisocytosis seen in RDW be reflective of systemic inflammation or oxidative stress in
diverticulitis? Offering some biological explanations would further strengthen the discussion’s
insight into how RDW correlates with disease severity.
-RDW can be influenced by multiple factors, such as anemia or nutritional status, which may
not be fully addressed in the discussion. A deeper dive into how these confounding factors were
controlled or their potential impact on the results would be valuable. For example, could patients
with anemia have skewed RDW values, and if so, how does the study account for this?
-While RDW's relationship with disease severity is highlighted, it would be useful to contrast
RDW more explicitly with other inflammatory markers. For example, how does RDW perform
relative to other established markers like neutrophil-to-lymphocyte ratio (NLR) or platelet-to-
lymphocyte ratio (PLR)? This comparison would help better position RDW within the broader
landscape of clinical markers for diverticulitis.
-The discussion could consider whether RDW might have implications beyond the initial
management of diverticulitis, such as predicting long-term outcomes, including recurrence or
complications. This would extend the utility of RDW as a biomarker and help establish its
broader clinical relevance.
-While the sensitivity and specificity of RDW in predicting the need for invasive treatment are
presented (75.86% sensitivity, 63.87% specificity), these values suggest that the marker is not
perfect. It would be beneficial to discuss these values in more in-depth. Could RDW be used
in conjunction with other parameters to improve its diagnostic accuracy? How do these values
compare to existing clinical markers, such as CRP?