[Chronic cold agglutinin disease occurring after a diagnosis of aplastic anemia].

We report herein a 61-year-old man with chronic cold agglutinin disease which occurred after a diagnosis of aplastic anemia. The patient's pancytopenia was recognized upon visiting a local doctor because of high fever and cough on December 21, 1985. He was subsequently admitted to our hospital because of anasarca on January 31, 1986, and was diagnosed as having aplastic anemia. He was treated with prednisolone, and was discharged after his anemia improved. He was readmitted on October 23, 1988, because of icterus. Laboratory data on the patients second admission revealed increased reticulocyte count, hyperplastic bone marrow with a predominance of erythroblasts, increased serum indirect bilirubin, increased serum LDH1 value and decreased serum haptoglobin. Moreover, cold agglutinin titer was increased, anti-IF antibody was positive, and anti-IgM antibody was recognized with direct anti-globulin test. There was no precedent infection such as mycoplasma pneumonia or infectious mononucleosis. Hence, this patient was diagnosed as having chronic cold agglutinin disease.