Anemia in inflammatory bowel disease: A neglected issue with relevant effects

Abstract

Anemia, a common complication associated with inflammatory bowel disease (IBD), is frequently overlooked in the management of IBD patients. Unfortunately, it represents one of the major causes of both decreased quality of life and increased hospital admissions among this population. Anemia in IBD is pathogenically complex, with several factors contributing to its development. While iron deficiency is the most common cause, vitamin B₁₂ and folic acid deficiencies, along with the effects of pro-inflammatory cytokines, hemolysis, drug therapies, and myelosuppression, have also been identified as the underlying etiology in a number of patients. Each of these etiological factors thus needs to be identified and corrected in order to effectively manage anemia in IBD. Because the diagnosis of anemia in IBD often presents a challenge, combinations of several hematimetric and biochemical parameters should be used. Recent studies underscore the importance of determining the ferritin index and hepcidin levels in order to distinguish between iron deficiency anemia, anemia due to chronic disease, or mixed anemia in IBD patients. With regard to treatment, the newly introduced intravenous iron formulations have several advantages over orally-administered iron compounds in treating iron deficiency in IBD. In special situations, erythropoietin supplementation and biological therapies should be considered. In conclusion, the management of anemia is a complex aspect of treating IBD patients, one that significantly influences the prognosis of the disease. As a consequence, its correction should be considered a specific, first-line therapeutic goal in the management of these patients.

Keywords: Anemia, Inflammatory bowel disease, Iron deficiency, Anemia of chronic disease, Erythropoietin

Core tip: Anemia represents one of the major causes of both decreased quality of life and increased hospital admissions among inflammatory bowel disease (IBD) patients. This paper analyses the complex etiological and pathophysiological mechanisms underlying anemia in IBD, including iron and micronutrients deficiency, effects of proinflammatory mediators and bone marrow insufficiency secondary to the disease by itself and IBD therapy. By a comprehensive review of the current diagnostic and therapeutic evidences on anemia in IBD, an state-of-the-art approach will be provided to effectively manage this challenging and common condition.