Ulcerative colitis associated with aplastic anemia; a case report

Anemia is the most common hematologic disorder in patients with ulcerativecolitis (UC). In some cases, normochromic anemia results from the presenceof chronic disease; however blood loss or malabsorption may lead to aniron deficiency anemia with hypochromic appearance. Other rare hematologicmanifestations associated with UC include myelodysplastic syndromes andleukemia. Several investigators have suggested a clinical association betweeninflammatory bowel disease and myelodysplastic syndrome, which may theyshare an immune dysfunction and impairment of T-lymphocytes activities.UC is an inflammatory bowel disease of unknown etiology that mainly affectsthe mucosa of the colon. Immune mechanisms play an important role in UC,and immunogenetic factors have been implicated in the development of thedisease. Aplastic anemia is a bone marrow stem cell disorder characterized byineffective hematopoiesis, leading to pancytopenia. Although aplastic anemiais frequently idiopathic, the immune-mediated suppression of hematopoiesismay be implicated in at least half of patients, since more than half of thesepatients achieve hematological remission in response to immunosuppressivetherapy. We report here a rare case of UC associated with pancytopenia requiringa blood transfusion in which a bone marrow examination showed aplasticanemia. A common pathogenic link between UC and aplastic anemia is suggestedin this patient on the basis of the shared immunologic impairment underlyingboth diseases.