Background

Human herpesvirus-8 (HHV-8) infection is endemic in Uganda and has an estimated 36%-60% seroprevalence. This virus is in the oropharynx and peripheral blood of Ugandans with Kaposi’s sarcoma, and viremia is increased in those with HIV-1. While Kaposi’s sarcoma is widely recognized as both endemic and with HIV epidemic, HHV-8 associated lymphoproliferative disorders have not been previously reported in Uganda. Evidence for these disorders was sought in lymphoma surveys conducted by sub-Saharan African Lymphoma Consortium (SSALC) consortium members in Uganda.

Materials and methods

Samples of 456 malignant lymphoma and adenopathy cases in formalin-fixed paraffin-embedded (FFPE) blocks from the Uganda SSALC and the Uganda AIDS and Cancer Specimen Resource (ACSR) were examined for morphology and Lana-1 (immunohistochemical, IHC) for diagnosis of HHV-8 lymphoproliferative disorders. Samples were also tested (IHC and in situ hybridization, ISH) using 20 monoclonal antibodies for common NHL antigens, ISH for EBV-encoded RNA, and kappa/lambda light chains (ISH, Ventana, Tucson).

Results

Many but not all of reported HHV-8-related proliferative disorders were identified in this sample population. Those identified and remaining to be identified are listed in Table 1.

Table 1 Subtypes.
Full size table

Conclusions

HHV-8 proliferative disorders excluding Kaposi’s sarcoma are present but generally not recognized by Ugandan clinicians and pathologists. Disorders are present in Uganda, especially in HIV-positive patients, in association with the high infection rates of both HIV-1 and HHV-8. Recognition is important because HHV-8 infection in HIV-1-positive patients associates with poor prognosis. Familiarity with the clinical presentation and tissue morphology of these disorders will likely result in recognition of the full range of reported HHV-8 proliferative complications. HHV-8-related lymphoma has increased prevalence in the HIV-1 infected. It arises and progresses in the face of highly active antiretroviral therapy immune reconstitution, making recognition of these disorders critical to patient care. We participate in the Sub-Saharan Africa Lymphoma Consortium [http://www.ssalc.org] to expand the understanding of HIV/AIDS-related malignancies and viral proliferative disorders in this region of the world.