Title: Alteration of stool pH and its association with biomarkers of gut enteropathy among slum-
dwelling women of reproductive age in Bangladesh
Version: 1 Date: 28 Sep 2023
Reviewer's report:
Overall comment:
The authors aimed to quantify the potential of fecal pH as a biomarker of gut enteropathy in
reproductive-aged women to develop cost-effective and non-invasive tests to diagnose EED.
Through multiple linear regression modeling of data obtained from a previous study conducted
in the Mirpur area of Dhaka city, Bangladesh, the authors concluded that alkaline stool pH was
significantly associated with a decrease in fecal IAP levels, and acidic stool pH was significantly
associated with an increase in fecal LCN-2 levels, both of which affect intestinal inflammation.
This study provides progress in the characterization of EED in LMIC countries and offers a
potential field-useful diagnostic tool that is accessible to people living in resource-limited areas.
I offer the following comments as suggestions to strengthen the manuscript:
Major comments:
Line 48-51: It is unclear whether the negative impact of gut microbial diversity is due to high
diversity or low diversity; clarifying which would assist in understanding linkages between EED,
gut microbiota, and fecal pH.
Lines 73-76: What is the range of LCN-2 in which intestinal inflammation is considered severe,
and how does this overlap with the diagnosis for EED? Include the ranges of LCN-2 for each
category of intestinal inflammation.
Lines 100-106: How are slums or resource-limited environments defined in this study? Including
the definition provides a better picture as to what resources are available for treatment or
diagnostic treatment.
Lines 109-110: What is the percentage or ratio of women who were not enrolled in this follow-
up study? Was the loss of these mothers in this study considered in determining bias, particularly
if they were still pregnant or lactating?
Table 1: What does “Toilet facility (improve)” entail? Include the qualifications for improved
sanitation facilities in a footnote.
Lines 177-185: This background information may be more suited for the introduction section,
as it creates confusion as to the intent of this study. The highlighting of “maternal education,
maternal age, and maternal health status” appears to indicate that these are the key factors in
this study instead of fecal pH.
Lines 189-196: Consistent with the previous comment, the information provided about the
purpose of the study is somewhat redundant to the introduction paragraph specifying the purpose
and the significance. Either condensing the paragraph or moving it to the introduction will
provide more focus in the discussion section.
Discussion section: Given that cost-effectiveness is a key consideration in the development of
an applicable diagnostic tool for EED, what is the cost of the current standard, and what would
the cost be for the stool pH probe in these settings? Describing the difference between the two
may highlight the significance of these findings.
Discussion section: The manuscript may benefit from more interpretation of the results and how
it ties to the diagnostic of EED. Much of the discussion section further explained the background
necessary to understand the study, but the findings of the study were very briefly mentioned.
More explicitly listing out the results from the figures and emphasizing how this fills in the
knowledge gaps of EED may strengthen this manuscript.
Minor comments:
Line 107: Typo, remove “the” in “Mothers of the all the children…”
Line 176: Spell out the abbreviated words (LBW and SGA) at first use.
Line 203: Replace “lipocalin 2” with “LCN-2” for consistency with the rest of the manuscript.
Line 241: Remove “69” from “…a 69costly setup.”
Line 246: Replace “even though” with “since” in “should be interpreted in light of its limitations
even though they are anticipated…” Currently, the wording indicates that the findings of these
study are incompatible with high public health importance.
Line 201: Gut should be lowercase.