HHV-8-Associated Lymphoproliferative Disorders and Pathogenesis in an HIV-Positive Patient.

Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus, is a DNA oncovirus known for its role in the development of Kaposi's sarcoma (KS) and several lymphoproliferative disorders (LPDs). HHV-8 promotes lymphoproliferation via the activation of the interleukin-6 receptor signaling pathway, as well as a host of other regulatory mechanisms. The spectrum of HHV-8-associated LPDs is increasing. The World Health Organization has recently updated the classification of HHV-8-associated LPDs by introducing HHV-8-positive germinotropic LPD (GLPD) in addition to the previously recognized entities of HHV-8-positive diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS), primary effusion lymphoma (PEL), and HHV-8-positive multicentric Castleman's disease (MCD). We present here a case of an HIV-positive woman with a history of KS, who later developed three HHV-8-associated LPDs, including HHV-8-positive MCD, PEL, and GLPD. To the best of our knowledge, this is the first reported case of a patient with this combination of individually rare HHV-8-associated LPDs. This case illustrates the spectrum and the sequential development of the different clinical manifestations of HHV-8-associated diseases. Detection of HHV-8 can have clinical significance in the diagnosis and management of certain HHV-8-associated conditions. Recently discovered variants of HHV-8-associated LPDs indicate that this group represents a diverse spectrum of disorders, whose classification may require further refinement beyond the currently recognized entities.