Hypersplenism is an overactive spleen. The spleen is an organ found in the upper left side of your abdomen. The spleen helps filter old and damaged cells from your bloodstream. If your spleen is overactive, it removes the blood cells too early and too quickly.
The spleen plays a key role in helping your body fight infections. Problems with the spleen can make you more likely to develop infections.
Connell NT, Shurin SB, Schiffman FJ. The spleen and its disorders. In: Hoffman R, Benz EJ Jr, Silberstein LE, Heslop HE, Weitz JI, Anastasi J, eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, PA: Elsevier; 2013:chap 162.
Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.