[Autoimmune hemolytic anemia in a patient with idiopathic interstitial pneumonia].

We report a rare case of autoimmune hemolytic anemia (AIHA) complicated by idiopathic interstitial pneumonia (IIP). A sixty-year-old man was diagnosed as having IIP in January 2009. In March, when he was hospitalized for the introduction of home oxygen therapy, severe anemia was detected. Based on the findings showing elevated levels of lactate dehydrogenase and indirect bilirubin, a decreased level of haptoglobin, positive Coombs test, and splenomegaly, a diagnosis of AIHA was made. Although anti-DNA antibody was found, diagnostic criteria for systemic lupus erythematosus and other collagen diseases were not fulfilled. Therefore, we concluded that AIHA coexisted with IIP. Treatment with prednisolone led to improvement of both AIHA and IIP. There has not been any exacerbation even after a gradual reduction of prednisolone to 7.5 mg/day. Coexistence of AIHA and IIP is rare, and accumulation of case reports is needed to gain a better understanding of this condition.