Review for 10.1186/s12876-024-03208-9 (2024)

Title: Patients with chronic hepatitis B who have persistently normal alanine aminotransferase
or aged < 30 years may exhibit significant histologic damage
Version: 0 Date: 02 Jan 2024
Reviewer:  Leon Louis Seifert
Reviewer's report:
Wei et al. present an interesting study which indicates that liver damage occurs already at young
age and in the absence of ALT elevations in CHB patients. This is of importance, as age and
ALT levels in addition to HBV DNA levels are used as the main determinants to decide whether
antiviral therapy is initiated or not. The results of this study are somewhat unexpected and can
contribute to ongoing discussions that generally aim at lowering the bar for treatment initiation.
A major advantage of this study is the large size of the patient including a large proportion of
patients <30.
I believe that the data from this patient cohort is precious and ultimately merits attention,
nonetheless several major and many minor issues have to addressed before I can recommend
the acceptance of this manuscript for publication.
Major comments:
Table 1:
1. In table 1 the range of patient ages is 21 to 36, unless the authors state the SD which would
be uncommon for the variable age and wrong. Looking at the figures, especially figure 1,
several patients included seem to be much older than 30 and up to 60. This is puzzling and
incomprehensive.
2. I would suggest to include the following variables if available: HBs and HBe status. % of
HBs positive cells. % of HBc positive cells, % of steatosis, AP, albumin, INR.
It would be very interesting to know the (estimated) duration of HBV infection as well as the
route of transmission (especially whether vertical transmission is suspected).
Patient cohorts:
I highly recommend to not only compare HBe-positive and negative patients, but more precisely
compare the 4 phases of CHB. The histological findings of the immunotolerant and inactive
carrier phase are similar, and likewise the immune-active phase and HBe negative hepatitis
phase show similar characteristics. Just comparing HBe-positive and negative combines these
(histologically) very different phases in larger cohorts and thereby prevents the authors from
observing any differences. I suggest to describe the entire cohort first and then provide a more
granular presentation with the 4 phases.
Multivariate analysis:
I see several issues with the multivariate regression analysis. First of all, the authors do not
clearly state how this was performed (what method, forward- or backward selection etc.).
Also, the authors make the common mistake to only include variables that are significantly
associated in the univariate analysis into their multivariate analysis, thereby potentially ignoring
confounding effects. Also, AST, ALT and GGT are likely all closely correlated. This represents
an issue as variables with close such correlation should be avoided in multivariate analysis,
especially if they account for 75% of variables. Mechanistically, I don’t really understand why
AST but not ALT should be associated with inflammation and fibrosis. As ALT is more liver
specific, I suggest to focus on ALT. Sex and age should be included in the multivariate analysis
despite not being significantly associate in univariate analysis.
Figure 1:
The authors do not indicate what the grey areas indicate. SD, SM etc.? A careful description of
all figures is necessary to allow adequate interpretation.
Figure 2:
Since ALT levels are used to determine whether treatment is initiated or not, it is appropriate to
use ALT for comparisons in this figure. On the other hand, the authors present that AST but not
ALT is associated with inflammation and fibrosis in their multivariate analysis in tables 2 and 3.
It would thus make sense to provide a similar analysis using AST levels. Anyhow, as I pointed
out above, I do not think that the multivariate analysis and thus the association with AST instead
of ALT is really reliable. But usage of ALT here is somewhat contradictory regarding the flow
of the manuscript in its current form.
Figure 2A: I understand that the statistical comparison are made between G0-1 and G2 and
higher and no significance is observed comparing ages. Looking more granular at the percentage
of G4 (~9.2 vs. ~19.5%) I assume a very significant statistical difference between age groups
(above and below 30) would be observed. This appears to be like a little bit of ‘statistical cherry-
picking’. Also, to me in appears incomprehensive to plot G0-4 and than only compare merged
subgroups. I suggest to either plot G0-1 and G2-4 or provide statistical differences throughout
the distribution. Same applies to other sub-elements of Figure 2.
Figure 3:
The title ‘distribution’ is misleading as the figure does not present a distribution but just
compares single values (I suppose mean or median). It would much more interesting to see an
actual distribution though, thus for example a separated scatter plot + median/mean or something
similar.
Figure 1:
Minor comments:
Page 3, line 53: BMC Gastro readers would care not only about the HBV health burden in China,
but all over the world. I suggest to add the number of CHB cases worldwide
Line 72: I suggest to add in the text that you are referring to AASLD guidelines
Line 89: Please give a more precise definition of what you consider ‘voluntariyly undergoing
liver histology’. I guess the authors are talking about liver biopsy. I sincerely hope that all
patients and your institution undergo biopsies ‘voluntarlly’, otherwise this would be an ethical
disaster.
Line 90: Are all patients untreated and treatment-naïve at the time of inclusion? Prior therapies
with NAs or IFN might impact histology
Line 92: hepatic sclerosis is not known to me. Also, if talking about hepatic decompensation,
this is NOT a malignancy!
Line 93: What about PBC, PSC, aA1, Wilson and Hemochromatosis?
Line 112: Why Scheuer and not METAVIR or Ishak? Also, G0 and G1 are often not called
‘necroinflammation’ but just inflammation.
Line 124: What kind of multivariate logistic regression? Specifications needed
Lines 249-265: The authors nicely point out that their findings are different from other previous
published studies, indicating more liver damage even in the absence of ALT elevations.
Unfortunately the authors fail to provide an explanation for that. In my opinion, HBV genotypes,
duration of infection and other confounding factors should be dicussed.
Line 274-277: This is already extensively and detailed explained in the results part and the
figures.
Line 329: I do not think that ‘aggressive’ it the right term here. Rephrase.