1. From the Departments of Pathology (Drs Mansoor and DePalma), Medicine (Dr Wagner), and Anatomy and Cell Biology (Dr DePalma), George Washington University Hospital and School of Medicine, Washington, DC.
2. Reprints: Louis DePalma, MD, Division of Clinical Pathology, George Washington University Medical Center, 901 23rd St NW, Washington, DC 20037 (e-mail: LDP@gwu.edu).