Letter to Editor Re: Spectrum of Autoimmune Liver Disease and Real-World Treatment Experience From a Tertiary Care Hospital

We note, in Taneja et al’s interesting review of real world experience in autoimmune liver disease, the proportion with cross over syndromes (AIH-PSC, n=18; or AIH-PBC, n=18, among a total number of autoimmune patient of 275) [1Taneja S. Mehtani R. De A. Mitra S. Rathi S. Verma N. Premkumar M. Minz R. Duseja A. Das A. Singh V. Dhiman R.K. Chawla Y.K. Spectrum of Autoimmune Liver Disease and Real-World Treatment Experience from a Tertiary Care Hospital.J Clin Exp Hepatol. 2023 Mar-Apr; 13: 241-251https://doi.org/10.1016/j.jceh.2022.11.002Abstract Full Text Full Text PDF Scopus (0) Google Scholar]. Thinking about these conditions has developed recently, and we refer readers to Ricciuto et al’s opinion article in the Journal of Hepatology [2Ricciuto A. Kamath B.M. Hirschfield G.M. Trivedi P.J. Primary sclerosing cholangitis and overlap features of autoimmune hepatitis: a coming of age or an age-ist problem?.J Hepatol. 2023 Mar 2; S0168-S8278 (Epub ahead of print. PMID: 36870613): 00162-00169https://doi.org/10.1016/j.jhep.2023.02.030Abstract Full Text Full Text PDF Scopus (0) Google Scholar]. They counsel caution in commencing immunosuppressive therapy, postulating that the AIH component is part of the PSC spectrum, and not a separable entity that will reliably respond to treatment. Or, if the AIH does, the cholangiopathy may not. We note that in this cohort, 61% of the AIH-PSC group showed complete response to treatment, though long term follow-up data is not available. Regarding the AIH-PBC cohort, expert guidance has highlighted that ‘true’ overlap is rare, and it is more common to see inflammatory features accompanying PBC, possibly indicating a more aggressive course but not requiring immunosuppression [3Hirschfield G.M. Dyson J.K. Alexander G.J.M. et al.The British Society of Gastroenterology/UK-PBC primary biliary cholangitis treatment and management guidelinesGut. 2018; 67: 1568-1594Google Scholar]. Applicable to both situations, at times the phenotypic of one disease may dominate over the other. It is well observed that response to treatment is less satisfactory when there are two apparent phenotypes. Ricciuto at al’s call to understand PSC/AIH and AISC as part of a continuum speaks to our need, as clinicians, to place patients and their conditions into categories. The 'representiveness heuristic' sees humans recognise certain salient features and make the assumption that an unfamiliar phenotypic pattern will behave according to their expectations of the reference condition (AIH in this case) [3Hirschfield G.M. Dyson J.K. Alexander G.J.M. et al.The British Society of Gastroenterology/UK-PBC primary biliary cholangitis treatment and management guidelinesGut. 2018; 67: 1568-1594Google Scholar]. We know AIH, and we are comfortable with it. In AISC, hepatologists are provided with a more attractive condition – a sub-type of PSC that may respond to immune suppression. This can influence the way we speak to young patients and their parents. In challenging the current terminology they encourage us to widen our perspective, accept that treating immune activity may not be justified, and explore uncertainty with our patients. While we counsel families and initiate immunosupressive therapy in some cases, it is important not to allow concrete concepts to develop, for as it stands we are not able to offer confident prognoses, and certainly cannot translate our experience in older cohorts to teenagers and younger adults without remaining aware of the risks. 4Kahneman Daniel Tversky Amos "Subjective probability: A judgment of representativeness" (PDF).Cognitive Psychology. 1972; 3: 430-454https://doi.org/10.1016/0010-0285(72)90016-3Crossref Scopus (2508) Google Scholar. none.