CD7 positive acute myeloblastic leukemia exhibiting pleural and pericardial involvement as an initial manifestation

A 12-year-old girl was admitted to our hospital because of cardiac tamponade and pleural effusion. Her pericardial and pleural fluid contained myeloblasts and a diagnosis of acute myeloblastic leukemia was made from the findings of a bone marrow smear. She was classified as M4 acute myeloblastic leukemia according to French-American-British classification. The surface marker analysis of the blasts was positive for CD7, CD33, CD14, CD34 and HLA-DR. Leukemic pericardial effusion with cardiac tamponade and pleural involvement is very rare as an initial manifestation of acute myeloblastic leukemia. We report a case with a diagnosis of CD7+ acute myeloblastic leukemia presenting initially with pericardial effusion complicated with cardiac tamponade and pleural involvement as an unusual presentation.