Presence of Monoclonal and Oligoclonal B-Cell Proliferation in Fatal Infectious Mononucleosis
Epstein-Barr virus (EBV) is the causative agent of infectious mononucleosis (IM) and has been etiologically linked with endemic African Burkitt’s lymphoma, carcinomas originating in Waldeyer’s ring, thymus and B cell lymphomas in immunosuppressed patients. While IM is a polyclonal B cell proliferative disease in organ transplant recipients, polyclonal oligoclonal or monoclonal lymphoproliferative lesions carrying EBV genome can occur. Congenitally immunodeficient males with X-linked lymphoproliferative syndrome (XLP) usually develop fatal IM (FIM), acquired hypogammaglobulinemia or malignant lymphoma (ML) following infection with EBV. We examined immunoglobulin gene rearrangement in necropsy-derived tissue specimens from 7 patients with FIM occurring sporadically and 5 with XLP.