Ulcerative Colitis Associated with Aplastic Anemia; A Case Report

Anemia is the most common hematologic disorder in patients with ulcerative colitis (UC). In some cases, normochromic anemia results from the presence of chronic disease; however blood loss or malabsorption may lead to an iron deficiency anemia with hypochromic appearance. Other rare hematologic manifestations associated with UC include myelodysplastic syndromes and leukemia. Several investigators have suggested a clinical association between inflammatory bowel disease and myelodysplastic syndrome, which may they share an immune dysfunction and impairment of T-lymphocytes activities. UC is an inflammatory bowel disease of unknown etiology that mainly affects the mucosa of the colon. Immune mechanisms play an important role in UC, and immunogenetic factors have been implicated in the development of the disease. Aplastic anemia is a bone marrow stem cell disorder characterized by ineffective hematopoiesis, leading to pancytopenia. Although aplastic anemia is frequently idiopathic, the immune-mediated suppression of hematopoiesis may be implicated in at least half of patients, since more than half of these patients achieve hematological remission in response to immunosuppressive therapy. We report here a rare case of UC associated with pancytopenia requiring a blood transfusion in which a bone marrow examination showed aplastic anemia. A common pathogenic link between UC and aplastic anemia is suggested in this patient on the basis of the shared immunologic impairment underlying both diseases.