Kaposiform hemangioendothelioma presenting antenatally with a pericardial effusion.

We describe an infant presenting with fetal pericardial effusion requiring in utero pericardiocentesis. Important postnatal clinical features included recurrent pericardial effusion, progressive stridor, thrombocytopenia, anemia, and a mediastinal mass surrounding the heart and coronary arteries. Investigations and management consisted of repeat pericardiocentesis, platelet and red blood cell transfusions, laryngoscopy, creation of a pericardial window, and biopsy of the mediastinal mass. Diagnosis was made of Kaposiform hemangioendothelioma surrounding the base of the heart, trachea, and esophagus as well as Kasabach-Merritt phenomenon. The infant responded well to treatment with vincristine and prednisone.