The epidemiology of Kaposi sarcoma (KS), a rare malignancy prior to the advent of the AIDS epidemic, suggested a link between the development of disease and a transmissible agent. In 1994, a novel gamma herpesvirus was subsequently identified in KS biopsies. After sequence analysis of the genome and characterization of the viral life cycle, this virus was subsequently named human herpesvirus 8 (HHV-8), or Kaposi sarcoma associated herpesvirus (KSHV).
The first disease associated with HHV-8 infection was KS. However, it soon became appreciated that several other conditions, especially body cavity based lymphoma (also known as primary effusion lymphoma or PEL) and Castleman's disease, were also linked to this virus. Host factors influence disease expression, since HHV-8 seroprevalence is relatively common. The onset of disease typically occurs several years after acquisition of infection.
The diseases that are or may be associated with HHV-8 infection will be reviewed here. The epidemiology, mode of transmission, diagnosis, and treatment of HHV-8 infection are discussed separately. (See "Virology, epidemiology, and transmission of human herpesvirus 8 infection" and "Diagnosis and antiviral therapy of human herpesvirus 8 infection".)
The symptoms and signs of primary infection with subsequent HHV-8 seroconversion have been described in children, men who have sex with men (MSM), and immunocompromised hosts.
Children — Primary HHV-8 infection may be associated with fever and a maculopapular rash in immunocompetent children. Evidence of HHV-8 infection was determined by serology and polymerase chain reaction (PCR) of blood and saliva in a prospective study of 86 children who presented to an emergency department with a febrile syndrome of uncertain origin . Thirty-six (42 percent) were seropositive; 14 of these patients had PCR evidence of HHV-8 DNA (mostly in saliva), but only six had evidence supporting primary HHV-8 infection.