Sclerosing cholangitis associated with chronic cryptosporidiosis in a child with a congenital immunodeficiency disorder.

Primary sclerosing cholangitis (PSC) in children is a rare and incurable disorder of unknown etiology. We report an immunodeficient child with chronic cryptosporidiosis of the biliary tract leading to clinical, pathological, and radiographic findings consistent with PSC. This case documents the ability of Cryptosporidium to disseminate to extraintestinal organs, and suggests that chronic cryptosporidial infection of the biliary tract may be one etiological mechanism producing sclerosing cholangitis in immunodeficient children. The increased incidence of PSC in immunodeficient children may in part be due to their inability to resolve infections of the biliary tract, which may result in sclerosing cholangitis mimicking PSC. We submit that an aggressive diagnostic workup should be performed to rule out an infectious etiology of sclerosing cholangitis in immunodeficient patients who have findings of PSC, because specific chemotherapy against the infecting organism would potentially arrest progressive biliary obliteration.