Castleman's disease is a heterogeneous group of lymphoproliferative disorders of unknown aetiology. Recently, human herpesvirus type 8 (HHV-8) has been associated with various diseases in individuals with HIV infection, including Kaposi's sarcoma, B cell non Hodgkin's lymphomas, and Castleman's disease. In Castleman's disease it has been hypothesized that HHV-8, encoding a number of various virokines, can be responsible for clinical manifestations of the disease. Previously, two reports have described a clinical recovery from HIV-associated Castleman's disease: by administration of a monoclonal antibody neutralizing human IL-6 in one case, and in another case by treatment with highly antiretroviral therapy and anti-herpesvirus therapy, following splenectomy. We report two cases where HAART alone led to clinical recovery from Castleman's disease. In both the cases reported here, although follow-up biopsy was not performed, it is likely that the inhibition of HHV-8 replication and of virokine release, through the restoration of immunity by HAART, was the basis for the disappearance of the clinical symptoms, (C) 2000 The British Infection Society.