Hemolytic Anemia in Inflammatory Bowel Disease: Our "Gut" Tells Us to Blame the Drug

Background: Several studies determined that autoimmune hemolytic anemia (AIHA) is a rare extraintestinal IBD manifestation, related to the underlying disease activity. However, evidence linking biologic therapy to AIHA is sparse. Methods: This article reviews the evidence on the association of these clinical phenomena. Results: There are two retrospective studies and a few case reports linking biologic therapies to AIHA. Conclusions: While some autoimmune phenomenon triggered by our biologic therapies have been well recognized, we do not find the evidence associating these therapies to AIHA sufficiently compelling. Lay Summary This article reviews the association of hemolytic anemia and inflammatory bowel diseases and determines if they are secondary to an uncommon extraintestinal manifestation of the underlying disease, or do they simply represent an infrequent side effect of our therapies.