title: Estimation of human herpesvirus 8 prevalence in high-risk patients by analysis of humoral and cellular immunity.
abstract: BACKGROUND
  Immunocompromized individuals, such as patients with end-stage renal disease, transplant recipients, and HIV-infected patients, are at increased risk of acquiring human herpesvirus (HHV)-8 associated infectious complications. The prevalence of HHV-8 infection generally is determined by detection of immunoglobulin G. However, because serological assays differ greatly, estimations on the actual HHV-8 prevalence vary considerably.
  
  
  METHODS
  HHV-8-specific cellular and humoral immunity were analyzed in 128 controls, 73 patients on dialysis, 67 transplant recipients, and 69 HIV-infected patients with the use of flow cytometry and indirect immunofluorescence microscopy.
  
  
  RESULTS
  A higher seroprevalence (from 13.7% to 44.9%) was confirmed for all groups of immunocompromised individuals as compared with healthy controls (3.9%). Among immunocompetent individuals, as little as 12.5% had HHV-8 reactive T-cell frequencies greater than the detection limit. In line with a higher seroprevalence in immunosuppressed patients, HHV-8-specific T cells were detectable in 30.1% of dialysis patients, 20.9% of transplant recipients, and 24.6% of HIV-infected individuals. When combining the individual presence of either HHV-8-specific antibodies or T cells or both, the prevalence of HHV-8 infection approached 15.6% in healthy individuals and 41.1%, 40.3%, and 55.1% in dialysis patients, transplant recipients, and HIV-infected individuals, respectively.
  
  
  CONCLUSIONS
  The exclusive serological analysis considerably underestimates the prevalence of HHV-8 infection in all study groups. Thus, the combined quantitation of both humoral and cellular immunity may instead be a superior method to assign the individual HHV-8 status. Moreover, this study suggests that the relative contributions of humoral and cellular immunity in control of HHV-8 may be different depending on the type of immunodeficiency.
authors.affiliation: Department of Internal Medicine IV, University of Saarland, Homburg/Saar, Germany.
authors.forename: Brigitta M
authors.initials: BM
authors.lastname: Lönard
authors.forename: Martina
authors.initials: M
authors.lastname: Sester
authors.forename: Urban
authors.initials: U
authors.lastname: Sester
authors.forename: Hans W
authors.initials: HW
authors.lastname: Pees
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Mueller-Lantzsch
authors.forename: Hans
authors.initials: H
authors.lastname: Köhler
authors.forename: Barbara C
authors.initials: BC
authors.lastname: Gärtner
mesh_terms: D000328:Adult; D000368:Aged; D000917:Antibody Formation; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D005260:Female; D006566:Herpesviridae Infections / Q000453:epidemiology* / Q000821:virology*; D019288:Herpesvirus 8, Human / Q000276:immunology*; D006801:Humans; D007111:Immunity, Cellular; D016867:Immunocompromised Host / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D015995:Prevalence