Primary sclerosing cholangitis in genetically diverse populations listed for liver transplantation: unique clinical and human leukocyte antigen associations

Abstract

Primary sclerosing cholangitis (PSC) is well characterized in European populations. We aimed to characterize clinical characteristics and human leukocyte antigen (HLA) associations in a population of European American, Hispanic, and African American PSC patients listed for liver transplantation (LT). Population-stratified demographic, clinical, and HLA data from 6767 LT registrants of the United Network for Organ Sharing who had a diagnosis of PSC (4.7% of the registrants) were compared to data from registrants with other diagnoses. Compared to European Americans and Hispanics, African Americans were significantly younger (46.6 ± 13.7, 42.3 ± 15.9, and 39.7 ± 13.1 years, respectively; P = 0.002) and were listed with a higher Model for End-Stage Liver Disease score (15.2 ± 7.5, 14.9 ± 7.6, and 18.1 ± 9.3, respectively; P = 0.001); they were also less frequently noted to have inflammatory bowel disease in comparison with European Americans (71.4% versus 60.5%, P < 0.01). In multivariate analysis, African origin was a significant factor associated with listing for LT with PSC (odds ratio with respect to European Americans = 1.325, 95% confidence interval = 1.221-1.438). HLA associations in European Americans, Hispanics, and African Americans with PSC versus alcoholic liver disease were detected for HLA-B8, HLA-DR13, and protective HLA-DR4. However, HLA-DR3, which is in linkage disequilibrium with HLA-B8, showed associations only in European Americans and Hispanics. In conclusion, African Americans with PSC who are listed for LT differ clinically from European Americans and Hispanics. The association with HLA-B8 but not HLA-DR3 in African Americans should make possible the refinement of the HLA associations in PSC.