Human herpesvirus 8 and Epstein-Barr virus-related monotypic large B-cell lymphoproliferative disorder coexisting with mixed variant of Castleman's disease in a lymph node of a renal transplant recipient.

Human herpesvirus 8 (HHV8) has been related to some malignant lymphoproliferations, including post-transplant lymphoproliferative disorders (PTLD). We describe a case of a HHV8 and Epstein-Barr virus (EBV) positive large B-cell lymphoproliferation coexisting with Castleman's disease in the same lymph node of a long-term renal transplant recipient. Biopsy revealed mixed type of Castleman's disease and anaplastic cells showing IgA restriction, although molecular analysis failed to detect monoclonality. Only large cells were co-infected by both EBV and HHV8. After reduction of immunosuppression, the lesion partially regressed. After 1 yr, local evolution required surgery followed by irradiation. The present case represents a unique form of localized monotypic but polyclonal large cell PTLD associated with Castleman's disease. It can be added to PTLD with HHV8 and EBV co-infection.