Causes

It's not clear what causes Castleman disease. However, infection by a virus called human herpesvirus 8 (HHV-8) is associated with multicentric Castleman disease.

The HHV-8 virus has also been linked to the development of Kaposi's sarcoma, a cancerous tumor that can be a complication of HIV/AIDS. Studies have found that HHV-8 is present in nearly all HIV-positive people who have Castleman disease, and in about half of HIV-negative people with Castleman disease.