Immunomediated Non-alcoholic SteaTohepatitis; Prevalence and Characterization. INSTInCT Study

NAFLD is a common comordidity in patients with IMID, including inflammatory bowel disease and psoriasis.

Nevertheless, the prevalence of NAFLD and NASH in the IMID population is not clear, and the risk factors are not completely understood. Interestingly, NASH and most of IMIDs share main molecular and immunological mechanisms of disease, as the inflammatory pathways depending on TNFa or imbalance in T cell subtypes like Th17/Treg. This common pathogenesis may explain, at least in a subset of patients, the development of NASH in the absence of classic metabolic risk factor.

Thus, our main hypothesis is that in the NASH assciated to IMIDs two different phenotypes co-exist.

First, a predominantly inflammatory phenotype, and not associated to the metabolic syndrome ande second, a predominantly metabolic phenptype, strongly associated to he metabolic syndrome.

In this way, we believe that in a particular subset of NAFLD patients, NASH could be considered as an IMID, as most of the definiting features of IMIDs are present. To demonstrate our hypothesis, we consider a two-stage study. First, we will determine the NAFLD and NASH prevalence in a cohort of well-characterized IMID patients and controls. Second, we will adress the molecular and immunophenotype characterization in liver biopsies of NASH patients with and without the co-existence of IMIDs.