Lower Incidence of Biliary Carcinoma in Patients With Primary Sclerosing Cholangitis and High Serum Levels of Immunoglobulin E

Background & Aims High serum levels of immunoglobulin (Ig)E often are detected in patients with primary sclerosing cholangitis (PSC), but the clinical significance is not known. Methods We analyzed data from 44 patients with PSC and known serum levels of IgE. They were divided into groups called high IgE (>170 IU/mL; n=17) or normal IgE (n = 27). We compared occurrence of biliary carcinoma including cholangiocellular and gallbladder carcinoma, liver transplantation, and death between groups. Results The high IgE group had a later age of onset of PSC than the normal IgE group (54 ± 20 y vs 39 ± 16 y; P = .010); they also had a higher serum level of IgG (2078 ± 638 vs 1517 ± 475 mg/dL; P = .002) and IgG4 (104 ± 102 vs 38 ± 16 mg/dL; P = .002). Association with inflammatory bowel disease did not differ significantly between groups (5 of 17 vs 11 of 27; P = .661). No patient had biliary carcinoma in the high IgE group, but biliary carcinoma was observed during the follow-up period in 8 patients in the normal IgE group (0 of 17 vs 8 of 27; P = .016). The occurrence of biliary carcinoma, liver transplantation, or death did not differ between groups (4 of 17 vs 13 of 27; P = .124). Conclusions High serum levels of IgE often are observed in older patients with PSC and are associated with a reduced incidence of biliary carcinoma.