Primary sclerosing cholangitis (PSC) is a disease of unknown cause that effects the biliary tree and is closely associated with inflammatory bowel disease. We did a retrospective analysis of the risk factors associated with recurrence of PSC in an allograft after liver transplantation. Recurrence of disease, assessed by liver histology or imaging the biliary tree, occurred in 56 of 152 patients (37%) at a median of 36 months (range 1.4-120 months). Multivariate analysis showed that being male (relative risk 1.2, 95% CI 0.73-2.15) and an intact colon before transplantation (8.7, 1.19-64.48) were associated with recurrence. These observations could help elucidate the pathogenesis of the disease.