Background:  Kaposi’s sarcoma-associated herpesvirus is associated with Kaposi’s sarcoma, primary effusion lymphoma, and HIV-associated Castleman disease. Purported associations with other diseases, such as multiple myeloma, have now largely been disproved. Recently, a study suggested an association between KSHV and idiopathic pulmonary arterial hypertension (PAH). The aim of this study was to evaluate the prevalence of KSHV antibodies in plasma samples from HIV and non-HIV infected patients with PAH.

Methods:  We enrolled 93 patients in this study:  34 HIV-infected patients with PAH and 59 non-HIV-infected patients (47 with idiopathic PAH and 12 with PAH associated with other conditions). Antibodies to a latent nuclear antigen of KSHV were detected using an immunofluorescence assay on the PEL BC-3 cell line. Positive samples for KSHV antibodies were confirmed using an immunofluorescence assay that detect antibodies to KSHV lytic antigens (KSHV IgG IFA, Biotrin).

Results:  KSHV antibodies were detected in 8 of 34 (23.5%; 95% CI 9.3 to 37.8%) among HIV-infected patients with PAH. Using the same IFA assays, this prevalence is similar to that reported among HIV-infected patients without PAH. KSHV antibodies were detected in 3 of 59 (5.1%; 95% CI 0.0 to 10.7%) among non-HIV-infected patients (1 with idiopathic PAH and 2 with other form of PAH). This prevalence is similar to that reported among non-HIV-infected patients without PAH and especially among healthy blood donors.

Conclusions:  These results suggest that there is no association between KSHV and PAH in both HIV- and non-HIV-infected patients. The concomitant presence of KSHV antibodies and PAH seems rather due to the natural distribution of the virus.

Keywords: KSHV; antibodies; pulmonary arterial hypertension