Infectious mononucleosis and severe thrombocytopenia.

Two patients with infectious mononucleosis who presented with severe thrombocytopenia at diagnosis are described. Anti-platelet antibody was demonstrated in one patient. Both responded well to a short course of prednisone therapy. These cases are of interest in view of their rarity and illustrate the need for screening patients who present with thrombocytopenia for infectious mononucleosis.