Human herpesvirus 8 (HHV-8) and the etiopathogenesis of Kaposi's sarcoma

Abstract

OBJECTIVE: To review the current literature on human herpesvirus 8 with particular attention to the aspects related to the etiopathogenesis of Kaposi's sarcoma. MATERIALS AND METHODS: The authors searched original research and review articles on specific aspects of human herpesvirus 8 infection, including virology, epidemiology, transmission, diagnosis, natural history, therapy, and Kaposi's sarcoma etiopathogenesis. The relevant material was evaluated and reviewed. RESULTS: Human herpesvirus 8 is a recently discovered DNA virus that is present throughout the world but with major geographic variation. In the Western world, the virus, transmitted mainly by means of sexual contact, is strongly associated with Kaposi's sarcoma and body cavity-based lymphoma and more controversially with multiple myeloma and other non-proliferative disorders. There is no specific effective treatment, but HIV protease inhibitors may play an indirect role in the clearance of human herpesvirus 8 DNA from peripheral blood mononuclear cells of HIV-infected patients. Human herpesvirus 8 DNA is present in saliva, but there are as yet no documented cases of nosocomial transmission to health care workers. The prevalence of human herpesvirus 8 among health care workers is probably similar to that in the general population. CONCLUSION: Human herpesvirus 8 appears to be, at least in Western Europe and United States, restricted to a population at risk of developing Kaposi's sarcoma. Human herpesvirus 8 certainly has the means to overcome cellular control and immune responses and thus predispose carriers to malignancy, particularly Kaposi's sarcoma. The wide diffusion of Human herpesvirus 8 in classic Kaposi's sarcoma areas appears to represent an important factor in the high incidence of the disease. However, additional co-factors are likely to play a role in the development of Kaposi's sarcoma.

Disseminated classic Kaposi's sarcoma

“…The aetiology of this variant has been scarcely studied and has been related to infectious agents like cytomegalovirus, human papilloma virus and hepatitis A and B viruses, HHV-6 and -8 (HHV-8 viral DNA is detected in over 90% of KS lesions [6,7]). Other hormonal and vascular factors have been related.…”

Successful treatment with liposomal doxorubicin for widespread Kaposi’s sarcoma and human herpesvirus-8 related severe hemophagocytic syndrome in a patient with acquired immunodeficiency syndrome

“…The most common sites of extra-mucocutaneous KS involvement in AIDS patients are the lymph nodes, the gastro-intestinal tract, and the lungs [2]. Infection with human herpesvirus-8 (HHV-8) has been consistently associated with the development of KS [3]. HHV-8 is also linked to primary effusion lymphoma, and multicentric Castleman's disease [3].…”

“…Infection with human herpesvirus-8 (HHV-8) has been consistently associated with the development of KS [3]. HHV-8 is also linked to primary effusion lymphoma, and multicentric Castleman's disease [3]. In addition, a few cases of hemophagocytic syndrome (HPS), which is associated with KS or HHV-8-infection in AIDS [4][5][6] and post-transplantation patients [7] have been reported.…”

Avaliação da resposta tecidual "in situ" do fenótipo, da expressão de HHV-8/LANA e de citocinas em lesões cutâneas de sarcoma de Kaposi clássico e sarcoma de Kaposi associado à AIDS na era pré e pós-terapia anti-retroviral combinada

“…Desde o advento da terapia antiretroviral combinada (HAART) houve uma diminuição da incidência de SK-AIDS, no entanto, esse tumor ainda é considerado o mais prevalente em indivíduos com AIDS (Leão et al, 2002; Tese de Doutorado -Fernanda Guedes Luiz Monini et al, 2004, Torre et al, 2005. Essa terapia compreende a combinação de drogas que incluem os inibidores da transcriptase reversa análogos de nucleosídeo (ITRNs) com um inibidor da protease (IP), dois…”

“…O sarcoma de Kaposi (SK) é o tumor mais freqüente em indivíduos infectados pelo vírus da imunodeficiência adquirida (HIV) (Leão et al, 2002;Torre et al, 2005). É definido como uma neoplasia vascular, caracterizado por neoangiogênese, proliferação de células fusiformes "spindle-shaped", presença de infiltrado inflamatório linfomononuclear e edema (Ensoli et al, 2001).…”