Autoanti-C in a patient with primary sclerosing cholangitis and autoimmune hemolytic anemia: a rare presentation

Primary sclerosing cholangitis (PSC) is rarely associated with autoimmune hemolytic anemia (AIHA), and the presence of specific autoantibodies has not been reported previously. We present a unique case report of PSC associated with AIHA implicating autoanti-C. A 17-year-old girl was admitted to our hospital with PSC along with AIHA. Her blood sample demonstrated a positive direct antiglobulin test and a positive autocontrol in the antihuman globulin phase, confirming the patient had warm-reactive AIHA. Further testing showed the possibility of anti-C. The patient’s Rh phenotype was C+D+E–c–e+. Further testing with select cells, serial alloadsorption, and an elution confirmed anti-C specificity. The patient was transfused with two C–, crossmatch-compatible packed red blood cell units. The patient’s hemoglobin level and general condition showed improvement. This unique case report shows PSC associated with AIHA caused by autoanti-C. Usually, warm AIHA presents with a panreactive pattern, and it is difficult to find compatible blood. In this rare case, we could determine the specific antibody; efforts should always be made in cases of AIHA to identify the specificity of autoantibody.