title: Infection of mesothelial cells with human herpes virus 8 in human immunodeficiency virus-infected patients with Kaposi's sarcoma, Castleman's disease, and recurrent pleural effusions.
abstract: Recurrent pleural effusions are common complications of hospitalized patients with human immunodeficiency virus (HIV) infection and may pose difficult diagnostic dilemmas. A common cause of recurrent pleural effusions in up to 30% of HIV-seropositive patients is pulmonary involvement by Kaposi's sarcoma, a human herpesvirus 8 (HHV 8)-related neoplasm. The pathogenesis of these effusions is unclear. These recurrent effusions, although benign, have shown significant mesothelial atypia/reactive changes of uncertain etiology. We attempted to evaluate these effusions morphologically and molecularly for the presence of HHV 8, with particular attention to mesothelial cells. All recurrent pleural effusions, as defined by any effusion tapped for cytological examination on more than two occasions, in HIV-positive patients at the National Institutes of Health were examined from 1998 to the present. Cases were stratified according to patients with and without histologically confirmed HHV 8 disease manifestations. Five patients with HHV 8 diseases (four with disseminated Kaposi's sarcoma and one with Castleman's disease) were identified. As a control group, five effusions from HIV-seropositive patients without known HHV 8-related diseases were identified. Cytological examination of effusions in patients with HHV 8-related diseases demonstrated atypical/markedly reactive mesothelial cells accompanied by a polymorphous background of lymphocytes. Molecular studies for B- and T-cell clonality in microdissected whole samples showed no definitive clones in these cases. Conversely, polymerase chain reaction (PCR) studies for the HHV 8 virus was positive in these samples. PCR studies on pure populations of microdissected mesothelial cells from the HHV 8-related effusions were positive for HHV 8 sequences, whereas those from HIV patients with non-HHV 8 related diseases were negative. Immunohistochemistry for HHV 8 (monoclonal antibody to latent nuclear antigen (LNA-1; ORF-73) on cellblock material demonstrated scattered positive mesothelial cells in three of the five cases of HHV 8-associated effusions. HHV 8 has been recently implicated in the pathogenesis of Kaposi's sarcoma and primary effusion lymphoma. Mesothelial cells in recurrent pleural effusions from patients with Kaposi's sarcoma and Castleman's disease appear to be infected with HHV 8. Additional studies need to be done to define the role of mesothelial cell infection in the pathogenesis of these HHV 8-associated effusions and define the prognostic significance.
authors.affiliation: Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Building 10, Room 2A19, Bethesda, MD, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Bryant-Greenwood
authors.forename: Lynn
authors.initials: L
authors.lastname: Sorbara
authors.forename: Armando C
authors.initials: AC
authors.lastname: Filie
authors.forename: Richard
authors.initials: R
authors.lastname: Little
authors.forename: Robert
authors.initials: R
authors.lastname: Yarchoan
authors.forename: Wyndham
authors.initials: W
authors.lastname: Wilson
authors.forename: Mark
authors.initials: M
authors.lastname: Raffeld
authors.forename: Andrea
authors.initials: A
authors.lastname: Abati
mesh_terms: D001402:B-Lymphocytes / Q000276:immunology; D005871:Castleman Disease / Q000209:etiology / Q000821:virology; D004279:DNA, Viral / Q000032:analysis; D004848:Epithelium / Q000821:virology*; D015658:HIV Infections / Q000150:complications; D006566:Herpesviridae Infections / Q000150:complications*; D019288:Herpesvirus 8, Human; D006801:Humans; D007150:Immunohistochemistry; D010996:Pleural Effusion / Q000209:etiology* / Q000276:immunology / Q000821:virology*; D016133:Polymerase Chain Reaction; D012514:Sarcoma, Kaposi / Q000209:etiology / Q000821:virology; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D004279:DNA, Viral