DISTRIBUTION OF HUMAN-HERPESVIRUS-8 DNA IN TUMOROUS AND NONTUMOROUS TISSUE OF PATIENTS WITH ACQUIRED-IMMUNODEFICIENCY-SYNDROME WITH AND WITHOUT KAPOSIS-SARCOMA

Human herpesvirus 8 (HHV-8) DNA is present in virtually all Kaposi's s arcomas (KSs), Conflicting results, however, exist with respect to the presence of HHV-8 in nontumorous tissue samples, To define the specif icity and predictive value of HHV-8 DNA detection in KS, we analyzed a utopsy-derived tissue samples from patients with acquired immunodefici ency syndrome (AIDS) with and without KS for the presence of HHV-8 DNA , using single-step and nested polymerase chain reaction. Semiquantita tive analysis of HHV-8 DNA was performed by endpoint dilution assays. HHV-8 DNA was detected in 41 (100%) tumor tissue samples of KSs. Accor ding to nested polymerase chain reaction results, HHV-8 DNA tvas also present in 16 (32%) of 50 nontumorous specimens of patients with AIDS patients with KS and in 3 (2.7%) of 113 specimens of patients with AID S without KS; it was absent in 26 autopsy tissues and 15 transurethral resected prostatic specimens of patients without AIDS. By use of a se cond, unrelated primer set, the presence of HHV-8 DNA was confirmed in 12 (63.2%) of 19 nontumorous samples and detected in another 6 (17.7% ) of 34 samples tested. Significantly higher titers of HHV-8 DNA were found in tumorous than in nontumorous tissues samples (1.9 x 10(4) vs, 1.2 x 10(2); P < .05), Specificity and positive predictive values for the diagnosis of KS by detecting HHV-8 DNA in a given tissue sample w ere 56 and 65.1% in patients with manifest KS and 97.4 and 100% in pat ients without previously known KS. An increased specificity and a posi tive predictive value were observed when the presence of KS anywhere i n a given patient was considered (92.9 and 77.8%, respectively). In co nclusion, the detection of HHV-8 DNA is a sensitive test for the diagn osis of KS. Its specificity, however, might be lower because HHV-8 can be detected in histologically unaffected tissue of patients with KS.