Transient leukemia-associated pericardial tamponade in a neonate with Down syndrome.

Approximately 10% of neonates with Down syndrome may develop a form of megakaryoblastic leukemia that usually disappear spontaneously during the first months of the life. Although it seems to have a benign course, it may also be lethal and severe in some cases, especially in the form of hydrops and/or cardiopulmonary failure. Herein, we report a male infant with Down syndrome who was admitted with respiratory distress due to severe pericardial effusion leading to pericardial tamponade in the first 2 weeks of life.