Heterosexual transmission of Kaposi's sarcoma-associated herpes virus between two patients developing AIDS-Kaposi's sarcoma.

Abstract

Kaposi's sarcoma-associated herpes virus (KSHV), also known as human herpes virus 8, has been closely related to all types of Kaposi's sarcoma (KS) [1]. In western countries KS is much more common in homosexual men with AIDS than in other risk groups, and different serological studies [2] suggest that KSHV can be transmitted through homosexual contacts. In contrast, little is known about other possibilities of KSHV transmission. Weansmitted through homosexual contacts. In contrast, little is known about other possibilities of KSHV transmission. We report here a biological and clinical observation of the heterosexual transmission of KSHV. Two married, heterosexual partners were followed up for their HIV-1 infection at the Bordeaux University Hospital. Both patients developed AIDS-associated KS concomitantly. At the time of AIDS–KS diagnosis, the man had a CD4 cell count of 0; he developed extensive KS including multivisceral localizations and died 4 months later. The woman had a CD4 cell count of 256 cells/μl at the time of KS, which also evolved with cutaneous and visceral symptoms. A retrospective serological study was carried out, using frozen sera samples. KSHV serology was determined with an indirect immunofluorescence assay using the KS-1 cell line (Biotrin, Ireland). The sensitivity of the test had previously been shown to be 98%, using 50 sera samples from AIDS–KS patients (data not shown). The serological data for the two patients are shown in Table 1.Table 1: Evolution of anti-Kaposi's sarcoma-associated herpes virus antibodies in the two patients before Kaposi's sarcoma. The woman seroconverted to anti-KSHV antibodies at approximately one year before the time of KS outcome, whereas her husband had a positive KSHV serology at least 2 years before the diagnosis of KS. In order to document the molecular characteristics of the viruses infecting the two patients, DNA was extracted from frozen KS cutaneous biopsies from both patients. A 330 bp DNA fragment encoding for the KSHV minor capsid protein was then amplified using the polymerase chain reaction. The nucleotide sequence analysis showed a complete identity of the KSHV sequences from the two patients; the viral genotype corresponded to the subtype B of KSHV, which had previously been shown to be predominant in France [3]. The same sequence homology was found when the KSHV ORF 75 nucleotide sequences from the two patients were compared. Taken together, these serological and molecular findings strongly suggest the heterosexual transmission of KSHV from the man to his wife, although transmission through saliva might also have occurred; the seroconversion of the woman was then followed by KS outcome. AIDS–KS is not frequent in women from western countries, and is generally observed in patients who have sexual relations with bisexual men; these circumstances cannot be excluded in this report. The possibility of a wider heterosexual transmission of KSHV has, however, to be considered, especially in subsaharan Africa, where the prevalence of KSHV is high [4]. Heterosexual transmission of KSHV should also be studied in patients with iatrogenic immunodeficiency, in whom KSHV seroconversion has been shown to be predictive of KS [5]. Bernard Masquelier Franck Boralevi Patrick Mercié Michel Dupon Hervé J. A. Fleury