Review for 10.1186/s12876-025-03693-6 (2025)

Title: Clinical and Microbiological Profile of Patients with Diarrhea Evaluated Using the
Gastrointestinal Panel in a High-Complexity Center
Version: 3 Date: 10 Nov 2024
Reviewer's report:
The title says "optimization of diagnosis" and therefore implies the assumption that with the
application of a gastrointestinal panel the diagnosis is better, therefore, in this order of ideas,
the methodology would be expected to deal with a study comparing conventional diagnostic
methods (fecal cultures) vs. molecular tests (gastrointestinal panel). However, the words of
the title are not consistent with the methodology. In the methodology section, it is explicitly
mentioned to compare immunocompetent vs. immunocompromised patients. But in the text, a
general description of many other variables and statistical associations is made.
Regarding the meaning of the title, the manuscript only mentions that the differences in
test positivity were seen only by gender, but there were no differences in the chronological
classification of diarrhea, nor differences related to the patients' diseases or immunosuppression
status.
It is well known in the literature that molecular panels favor etiological diagnosis in terms of
sensitivity, specificity and diagnostic accuracy in different clinical scenarios, including patients
with acute diarrhea. We know that molecular panels help in optimizing antibiotic prescription.
Following these ideas, one could then imagine that what is wanted to be explored in this
research with the methodology is whether gastrointestinal panels favor etiological diagnosis in
immunosuppressed patients with diarrhea. In this regard, what is mentioned in the manuscript
is that enterotoxigenic E. coli (ETEC) was more prevalent in immunosuppressed patients (4.7%
vs. 1.4%; P=0.097). But, this does not justify the publication of the manuscript.
Also, it must be said that many ideas and results are explored in the manuscript, but it does not
focus on a single research objective.
After reading it, it is clear that this is a descriptive study. However, in the wording of the
results, they report that only 53% of the patients had a positive molecular GI panel. So, one
wonders, what exactly is being investigated? Based on this result, one would now think that
they are comparing patients with a positive test vs. patients with a negative test, to evaluate
the factors associated with a positive test vs. the factors associated with a negative test. Or
they want to compare the benefits of having a positive test (accurate etiologic diagnosis) vs. a
conventional diagnostic method ("optimization of diagnosis"), in which case, clinical outcomes
(days of hospital stay, mortality, etc.) should be reported.
Again, it is not clear from reading the manuscript what the objective of the research is. This is
evidenced above all by the lack of coherence between the title, the methodology proposed and
developed, and the results reported and discussed.
The results report "Inflammatory diarrhea was present in 60.1%", so one may wonder what other
pathophysiological types of diarrhea did the remaining 39.1% of patients have? If they did not
have inflammatory diarrhea, why were they tested with a gastrointestinal molecular panel? Why
were they doing an exhaustive microbiological etiological search? The question also arises about
what was the clinical selection criteria at the study center to establish which patients are tested
with a gastrointestinal molecular panel. This is important because the title highlights that the
study is being conducted in Colombia, a country with a high level of inequality and in which most
study centers do not have diagnostic molecular gastrointestinal panels available. It is mentioned
that a certain percentage of patients were from the outpatient setting, therefore, one imagines
that the population is quite heterogeneous, decreasing external validity.
The clinical indication for a GI panel is most evident in patients with some form of
immunosuppression (who were 39.1% of the patients) and in patients with sepsis, in whom the
use of antibiotics may be accelerated and in whom obtaining an accurate diagnosis may be crucial
for the outcomes. Despite this, the prevalence of sepsis is not reported in the study. Infectious
etiologies are more common in acute diarrhea. In chronic diarrhea (14% of the patients in the
study) the diarrhea may be watery, fatty (malabsorption), or infectious.
The segment that discusses the impact of the diagnostic test is very interesting. The diagnostic
test only had an impact on 56.7% of the population and in these patients, the impact consisted
in that 45.6% remained WITHOUT antibiotics, therefore, in the Colombian context of limited
economic resources, an expensive test was done to confirm that clinically the patient did not have
an infection and did not need antibiotics (this is important from the point of view of antimicrobial
resistance). If one analyzes this information contrasted with the fact that 41% of the population
only received empirical antimicrobial treatment, the first thing that comes to mind is that the
gastrointestinal panel test was possibly overused. The question remains again as to what are the
clinical criteria for performing this diagnostic test in the study center. If one wants to analyze
the Colombian context, this becomes very relevant. The manuscript says "It was found that the
initiation of initial treatment was more frequent in immunosuppressed patients" but the reported
P value is greater than 0.05 (p=0.082). This should be corrected.
The article contains very interesting data and addresses a clinically relevant topic. I recommend
that the authors reorganize the ideas and the wording of the title and methodology, because from
my point of view, it seems to be a purely descriptive study, but throughout the writing of the
manuscript ideas are expressed that are not related to the methodology or the title. This has to do
precisely with the fact of clearly expressing a specific objective, a clear question to be answered
with the research.
It is mentioned in the title that the study locates patients from the "Colombian context" but the
study is carried out in a highly complex center with many resources, and nothing special is
discussed in the manuscript about the social or economic implications of the study being from
Colombia. This expression "Colombian context" could be omitted.
Was the gastrointestinal panel FilmArray? I think this should be specified in the methodology.
As a suggestion, the authors could focus only on one aspect, for example: 1) on the clinical
impact of the gastrointestinal panel in terms of the prescription of antimicrobials; 2) factors
associated with a positive test vs. factors associated with a negative test (gastrointestinal panel);
3) impact of the gastrointestinal panel on acute diarrhea, or on persistent or chronic diarrhea, or
on immunosuppressed patients with diarrhea, on a specific outcome, etc.