Epidemiological features of immunoglobulin G4‐related sclerosing cholangitis in Japan

Background/Purpose Epidemiological data on immunoglobulin G4‐related sclerosing cholangitis (IgG4‐SC) are scarce. Method We randomly selected healthcare facilities from a list of all facilities in Japan. The selection rate was determined according to a stratification based on the facility characteristics and scale. We sent questionnaires to the selected facilities enquiring about the number and sex of patients with IgG4‐SC in 2018. Among...