Clinical types:
(1) classic, in adult males from Eastern Europe and around the Mediterranean
(2) African (endemic)
(3) AIDS-related
(4) immunosuppression-related (iatrogenic)
Classic type:
(1) It tends to follow a slow and indolent course.
(2) Some cases have been associated with exposure to volcanic dust containing silicates. Silicosis is associated with immune dysfunction. Silicosis also can be an occupational disorder which may explain the frequency in adult males.
(3) Some cases are associated with lymphopenia (Brown et al.)
African or endemic:
(1) It is seen in central Africa and can be more serious in children.
(2) HHV-8 may be transmitted by blood-sucking arthropods.
AIDS-related:
(1) It is an AIDS-defining condition in HIV disease and is associated with worsening immunodeficiency.
Immunosuppression-related:
(1) It is reported in organ transplant recipients but can occur in anyone who is sufficiently immunosuppressed.
How the type is assigned:
(1) If the person is HIV-positive, then the case is HIV-related.
(2) If the person is immunosuppressed, then the cause is immunosuppression.
(3) If the person is African or Mediterranean/Eastern European then the location defines the type.
(4) If none of these are found then the case is idiopathic. It is important in these cases to look for an underlying immune defect.
