Rapidly involuting congenital hemangioma associated with profound, transient thrombocytopenia.

Rapidly involuting congenital hemangioma (RICH) is an uncommon, often high-flow vascular tumor that presents at birth and involutes within the first year of life. It is clinically and histologically distinct from infantile hemangioma, kaposiform hemangioendothelioma, and tufted angioma, the latter two being associated with Kasabach-Merritt phenomenon. We present a female infant with RICH and profound, transient thrombocytopenia and review the extent and clinical course of thrombocytopenia in the context of congenital vascular tumors.