Infectious Mononucleosis - Tonsils

Comments:
Infectious Mononucleosis - Tonsils: Binucleated, Reed-Sternberg (RS)-like immunoblasts in a tonsil from a 17 y/o patient with infectious mononucleosis. The patient presented with sore throat, difficulty breathing, and dysphagia of 2 weeks' duration. A monospot test was positive.

RS-like cells (seen in the center of this image) usually co-express CD30 and CD20 but are CD15-negative.