Splenic Sequestration

**Semantic type:** Finding

**Definition:** A complication of sickle cell conditions that is characterized by splenomegaly due to vaso-occlusion and pooling of red blood cells within the spleen. A splenic sequestration crisis is an acute, life-threatening episode that is characterized by a severe drop in serum hemoglobin, usually by more than 2g/dL from baseline.