A disease-specific decline of the relative abundance of Bifidobacterium in patients with autoimmune hepatitis.

Background: The pathogenesis of autoimmune hepatitis (AIH) is poorly understood and little is known about enteric microbiota in AIH.

Aim: To investigate disease-specific microbiome alterations in AIH.

Methods: The V1-V2 variable regions of the 16S rRNA gene were sequenced in faecal samples from 347 patients with AIH and controls (AIH n = 72, healthy controls (HC) n = 95, primary biliary cholangitis (PBC) n = 99 and ulcerative colitis (UC) n = 81).