International Society of Dermatology - Palm Coast, FL - USA

Author: Nicolas Dupin
nicolas.dupin@cch.aphp.fr

ABSTRACT

KSHV/HHV-8 is associated with all epidemiologic forms of Kaposi sarcoma (KS), with the multicentric plasma cell type of Castleman’s disease and with primary effusion lymphoma. The prevalence of KSHV is variable with 3 different profiles (low, intermediate and high-profile). The virus may be transmitted sexually in MSM. It can be transmitted from mother to child or from child to child suggesting horizontal transmission and it could be transmitted via solid organ transplants while transmission via blood products seems to be marginal. The value of KSHV viremia is demonstrated in HIV infected patients with KS and in patients with Castleman while the place of monitoring KSHV viral load in blood from patients with HIV unrelated KS is still controversial.
In KS lesions, most of the infected cells are latently infected while a subset of cells of unknown origin may be lytically infected. The preferential target cells of KSHV are endothelial cells and recent studies suggest that these cells may derive from lymphatic endothelial cells although some works suggest that KSHV infection of microvascular
endothelial cells may drive these cells to a lymphatic genotypic and phenotypic profile.
KS is very sensitive to immunosuppression and is one of the best example of what we can call an opportunistic tumor. This is illustrated by the resolution of KS in the setting of HIV with antiretroviral combination therapy which is mainly due to immune restoration. Some of the antiretroviral drugs as the protease inhibitors (PI) may have anti-angiogenic activities that could participate to KS resolution.