Concurrent oral lichen planus and primary sclerosing cholangitis.

Four patients with concomitant oral lichen planus (OLP) and primary sclerosing cholangitis (PSC) are presented. Associations have been made between OLP and chronic liver disease, namely hepatitis C and primary biliary cirrhosis, but the aetiology and commonality between the diseases has yet to be confirmed. An immunological link is currently favoured. PSC may be a further association with OLP, possibly involving the immune system.