Detection of Human Herpesvirus 8 in Australian HIV-Positive Patients

1School of Dentistry and Oral Health, Griffith University, Southport, Australia. 2School of Medicine, Griffith University, Southport, Australia

Objectives: HHV-8, regarded as the aetiological agent of Kaposi’s sarcoma (KS), multicentric Castleman’s disease (MCD) and primary effusion lymphoma (PEL) has been extensively characterized worldwide but overlooked in Australia as HAART has greatly reduced the incidence of KS as an AIDS-defining condition. Globally, there is marked variability in the prevalence of KS. In Australia the prevalence of both HIV (0.1%) and of HHV-8 appears to be low, but there are no population data for the latter. Our overall objective is to fully characterize HHV-8 in Australia, as part of a multinational study which includes high-prevalence parts of the world. In the latter, oral KS is common. This pilot study describes HHV-8 in KS and MCD biopsies from both HIV-positive and –negative Australian patients.

Methods: 21 biopsies from 16 patients (males:females, 15:1) with a mean age of 55.7 years (28.2-88.6 years) with KS or MCD diagnosed between 2004 and 2008 were examined by haematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) targeting the HHV-8 LANA-1 protein (NCL-HHV8-LNA; Novacastra). Positive controls were sections from embedded BCBL-1 cell lines. Confirmation of HHV-8 IHC staining was sought by polymerase chain reaction (PCR) targeting ORF73 and ORF26.

Results: HHV-8 was detected in two HIV-negative elderly males (78 and 88 years) with classic KS nodules on lower extremities and 10 HIV-positive males with a mean age of 4510 years. Biopsies of AIDS-KS positive for HHV-8 were taken from the epidermis except one from the duodenum. HHV-8 was also detected in a cervical lymph node from an HIV-positive male with MCD. PCR for HHV-8 ORF73 and ORF26 was confirmational in tissue positive by IHC.

Conclusions: HHV-8 was detected in KS and MCD biopsies in Australia by IHC and confirmed by PCR. This study reports the presence of HHV-8 from Australia and lays the foundation for determining the Australian HHV-8 strain and seroprevalence. Our ongoing collaborative studies in Africa include many oral lesions: those in India none, as KS is extremely rare in the subcontinent.