Castleman's disease is a rare disorder characterized by two distinct entities with similar histology but different time course and therapeutic response. Multicentric plasma cell variant is highly associated with infection by human herpesvirus 8 (HHV-8), but the pathogenesis of the hyaline vascular variant is currently unknown. We report a pregnant patient who develops a localized axillary hyaline-type Castleman's disease in which HHV-8 DNA sequences were detected in the lymph node lesions by nested PCR. In addition, the PCR multiplex also showed positivity for EBV. Immunohistochemical studies confirmed the presence of both viruses. Our results provide the first evidence of the presence of HHV-8 and EBV sequences in localized Castleman's disease, suggesting a possible role of the association of these herpes virus in the pathogenesis of this type of disorder. This case highlights that searching for HHV-8 and EBV sequences in cases of localized Castleman's disease is strongly advised.