Comparison of four histological scoring systems for autoimmune hepatitis to improve diagnostic sensitivity

Abstract

Background/Aims: The histological criteria in the 1999 and 2008 scoring systems proposed by the International Autoimmune Hepatitis Group (IAIHG) have their inherent limitations in diagnosing autoimmune hepatitis (AIH). In this study, we evaluated the histology components of four scoring systems (1. revised original scoring system [“1999 IAIHG”], 2. simplified scoring system [“2008 IAIHG”], 3. modified histologic criteria [“2017 UCSF”], and 4. a new histologic criteria proposed by the International AIH Pathology Group [“2022 IAHPG”]) in AIH patients.Methods: Medical records and liver biopsies were retrospectively reviewed for 68 patients from two independent medical institutions, diagnosed with AIH based on the 1999 IAIHG system between 2006 and 2016. The histological features were reviewed in detail, and the four histological scoring systems were compared.Results: Out of the 68 patients, 56 (82.4%) patients met the “probable” or “definite” AIH criteria of the 2008 IAIHG system, and the proportion of histologic score 2 (maximum) was 40/68 (58.8%). By applying the 2017 UCSF criteria, the number of histology score 2 increased to 60/68 (88.2%), and “probable” or “definite” AIH cases increased to 61/68 (89.7%). Finally, applying the 2022 IAHPG histology score resulted in the highest number of cases with histologic score 2 (64/68; 94.1%) and with a diagnosis of “probable” or “definite” AIH (62/68; 91.2%).Conclusions: The recently proposed UCSF/IAHPG histological criteria increased the histology score of AIH. Substituting the histology component of the 2008 IAIHG system with the 2022 IAHPG criteria increased the sensitivity for diagnosing AIH (≥“Probable AIH”) from 82.4% to 91.2%.

Evaluation of the histological scoring systems of autoimmune hepatitis: A significant step towards the optimization of clinical diagnosis

“…In this issue, Ahn et al [ 8 ] retrospectively evaluate the utility of the two modified histological scorings among patients originally diagnosed with at least probable AIH according to 1999 IAIHG by performing a comparison among four sets of diagnostic criteria, namely 1999 IAIHG, 2008 IAIHG, and 2008 IAIHGs, with the updated histological scorings of 2017 UCSF and 2022 IAHPG, respectively (2008 IAIHG+2017 UCSF and 2008 IAIHG+2022 IAHPG).…”

“…The need to do additional staining to identify Kupffer cells is a drawback of its routine implementation in clinical practice. So far, again, understanding the specific context of AIH inflammation in situ is the gold standard in AIH diagnosis, as in the findings by Ahn et al [ 8 ]; there is likely room for improvement in the future with assistance from artificial intelligence.…”

“…The study by Ahn et al [ 8 ] was a retrospective study with only a relatively small number of Korean AIH patients in the absence of a control group with other etiologies. In the future, multinational evaluation to validate the sensitivity and assess the specificity of the four diagnostic systems will be important, especially one that considers acute drug-induced liver injury, a most prominent disease entity that requires careful differentiation from AIH with acute presentation [ 12 ].…”

Reply to: “Evaluation of the histological scoring systems of autoimmune hepatitis: A significant step towards the optimization of clinical diagnosis”

“…We would like to thank Dr. Atsumasa Komori for his interest in our study entitled “Comparison of four histological scoring systems for autoimmune hepatitis (AIH) to improve diagnostic sensitivity” and for the kind comments [ 1 , 2 ].…”