Review for 10.1186/s12876-023-03105-7 (2024)

Title: Evaluation of autoimmune liver disease natural history in patients referred to Middle East
Liver Diseases (MELD) center
Version: 1 Date: 14 Oct 2023
Reviewer's report:
In this revised version, the authors added some informations  however, other important points
needing to be addressed still remain.
1) The authors stated that Autoantibody detection for ANA was done by solid-phase
enzyme immunoassay (ELISA). ASMA, AMA, and Anti-LKM1, were assessed using indirect
immunofluorescence assays. However, it is well-known that the first step for autoantibody
detection, particularly for ANA detection, is represented by indirect immunofluorescence, as
previously recommended in a pivotal paper of the International Autoimmune Hepatitis Group
(J Hepatol. 2004;41(4):677-83. doi: 10.1016/j.jhep.2004.08.002). On the contrary, solid-phase
enzyme immunoassay (ELISA) may result in lower sensitivity/specificity. This is an important
issue since the authors found a frequency of ANA positivity in AIH and PBC patients (41.9%
and 18.9, respectively) lower than that reported in previous literature studies.The authors should
therefore recognize this difference and comment their findings at the light of the laboratory tests
used for autoantibody detection.
2) Diagnosis of AIH: regarding the diagnostic scoring systems, the authors stated that “for
routine clinical practice, we utilized the simplified criteria instead of the Revised Score System
for Diagnosis of Autoimmune Hepatitis (1999) scoring system”. However, this statement should
be supported by appropriate references since no previous studies had validated the diagnostic
accuracy of the simplified score in Iranian patients . If available, the authors should provide
also the result of the original revised score. Otherwise, If the results of the original score are
not available, the authors should state that they routinely use the AIH simplified score in light
of previous studies that have validated the diagnostic accuracy of the simplified AIH score
(2008) as previously demonstrated (Validation of simplified diagnostic criteria for autoimmune
hepatitis in Italian patients. Hepatology. 2009 May;49(5):1782-3. doi: 10.1002/hep.22825; J
Hepatol. 2011;54(2):340-7. doi: 10.1016/j.jhep.2010.06.032. Epub 2010 Sep 15).
3) PBC patients: according to table 2 results, only 67% of patients were AMA positive, and
only 18.9% were ANA positive. According to previously described autoantibody detection
details provided in the revised manuscript, it is not clear how the authors can explain the lower
rate of AMA positive PBC patients as well as the low rate of ANA positivity. According to
literature data, 90-95% of PBC patients are AMA positive and nearly 50% are ANA positive.
PBC patients lacking AMA are mostly positive for the so-called “PBC-specific ANA” as
previously demonstrated in a large study of more than 4000 sera (Aliment Pharmacol Ther.
2006;24(11-12):1575-83. doi: 10.1111/j.1365-2036.2006.03172.x.).
The authors should further specify which antinuclear autoantibodies IIF patterns were
detected and whether ANAs were those recommended for the diagnosis of AMA-negative
PBC as described (EASL 2017 guidelines: J Hepatol. 2017;67(1):145-172. doi: 10.1016/
j.jhep.2017.03.022). To further improve the manuscript and add clinical significance of the
study, the authors should discuss this point according to the above-mentioned literature data to
compare their findings with previous studies from other geographical areas.
4) acute AIH: diagnosis of acute AIH is challenging since it has been previously reported
that AIH patients with “acute” presentation are more frequently autoantibody seronegative and
display normal gamma-globulin serum levels thus making the diagnostic performance of the
simplified AIH score lower than that of the original (1999) score, as recently demonstrated
(Limitation of the simplified scoring system for the diagnosis of autoimmune Hepatitis with
acute onset. Liver Int. 2021 Mar;41(3):529-534. doi: 10.1111/liv.14778.).
5) Discussion: the authors discuss the impact of genetic background in clinical/autoantibody
profiles worldwide. However, no reference supporting such a difference is included. While
ANA and SMA prevalence have more homogeneous value worldwide, LKM prevalence is
significantly affected by genetic background as previously demonstrated (Dig Dis Sci. 2007
Jan;52(1):179-84. doi: 10.1007/s10620-006-9495-4). In this regard, a significant findings of this
study, worth underscored is the low rate of LKM-positive AIH patients (3% as reported in (Table
2).