Chapter 249 Human Herpesvirus 8 Mary T. Caserta Human herpesvirus 8 (HHV-8) was first identified in tissue specimens from patients with Kaposi sarcoma (KS). Because of this association it is also known as Kaposi sarcoma–associated herpesvirus (KSHV). HHV-8 has since been recognized as the etiologic agent of two additional lymphoproliferative disorders: primary effusion based lymphoma (PEL) and multicentric Castleman disease. Etiology HHV-8 is a γ-2-human herpesvirus genetically most similar to Epstein-Barr virus. The virus contains a large DNA genome encoding for 85-95 unique proteins. Infection is followed by both lytic and latent viral states with different degrees of viral replication associated with distinct disease manifestations. Epidemiology The prevalence of infection with HHV-8 varies both geographically and by population and roughly matches the epidemiology of KS. HHV-8 is endemic in Africa and parts of South America, with infection rates of up to 30-60% by adolescence. Seroprevalence >20% has also been found in regions bordering the Mediterranean. In contrast, infection rates <5% are noted in North America, central Europe, and Asia. However, within geographical regions, the prevalence of infection varies with risk behaviors, rates of 30-75% being found among men who have sex with men in North America and Europe. HHV-8 DNA can be detected in saliva and genital tract secretions. Taken together, these findings lead to the recognition that saliva is the major mode of transmission to children in areas where HHV-8 infection is endemic, whereas sexual contact is a source of infection among adults in low-prevalence areas. Other less common routes of HHV-8 transmission include blood transfusion, bone marrow transplantation, and solid organ transplantation. Vertical transmission may occur in regions where HHV-8 is highly endemic, but the risk appears low. Pathology/Pathogenesis Only gold members can continue reading. Log In or Register to continue Share this: Share on X (Opens in new window) X Share on Facebook (Opens in new window) Facebook Related Related posts: Rumination, Pica, and Elimination (Enuresis, Encopresis) Disorders Adolescent Pregnancy Neisseria gonorrhoeae (Gonococcus) Blastomycosis (Blastomyces dermatitidis) Stay updated, free articles. Join our Telegram channel Join Tags: Nelson Textbook of Pediatrics Expert Consult Jun 18, 2016 | Posted by admin in PEDIATRICS | Comments Off on Human Herpesvirus 8 Full access? Get Clinical Tree
Chapter 249 Human Herpesvirus 8 Mary T. Caserta Human herpesvirus 8 (HHV-8) was first identified in tissue specimens from patients with Kaposi sarcoma (KS). Because of this association it is also known as Kaposi sarcoma–associated herpesvirus (KSHV). HHV-8 has since been recognized as the etiologic agent of two additional lymphoproliferative disorders: primary effusion based lymphoma (PEL) and multicentric Castleman disease. Etiology HHV-8 is a γ-2-human herpesvirus genetically most similar to Epstein-Barr virus. The virus contains a large DNA genome encoding for 85-95 unique proteins. Infection is followed by both lytic and latent viral states with different degrees of viral replication associated with distinct disease manifestations. Epidemiology The prevalence of infection with HHV-8 varies both geographically and by population and roughly matches the epidemiology of KS. HHV-8 is endemic in Africa and parts of South America, with infection rates of up to 30-60% by adolescence. Seroprevalence >20% has also been found in regions bordering the Mediterranean. In contrast, infection rates <5% are noted in North America, central Europe, and Asia. However, within geographical regions, the prevalence of infection varies with risk behaviors, rates of 30-75% being found among men who have sex with men in North America and Europe. HHV-8 DNA can be detected in saliva and genital tract secretions. Taken together, these findings lead to the recognition that saliva is the major mode of transmission to children in areas where HHV-8 infection is endemic, whereas sexual contact is a source of infection among adults in low-prevalence areas. Other less common routes of HHV-8 transmission include blood transfusion, bone marrow transplantation, and solid organ transplantation. Vertical transmission may occur in regions where HHV-8 is highly endemic, but the risk appears low. Pathology/Pathogenesis Only gold members can continue reading. Log In or Register to continue Share this: Share on X (Opens in new window) X Share on Facebook (Opens in new window) Facebook Related Related posts: Rumination, Pica, and Elimination (Enuresis, Encopresis) Disorders Adolescent Pregnancy Neisseria gonorrhoeae (Gonococcus) Blastomycosis (Blastomyces dermatitidis) Stay updated, free articles. Join our Telegram channel Join Tags: Nelson Textbook of Pediatrics Expert Consult Jun 18, 2016 | Posted by admin in PEDIATRICS | Comments Off on Human Herpesvirus 8 Full access? Get Clinical Tree
