Human herpesvirus-8 (HHV-8) sero-detection and HIV association in Kaposi's sarcoma (KS), non-KS tumors and non-neoplastic conditions

Amos R Mwakigonja¹^,2 , Pawan Pyakurel¹ , Parviz Kokhaei³^,4 , Fatemeh Pak¹^,3 , Leonard K Lema⁵ , Ephata E Kaaya¹^,2 and Peter Biberfeld¹

¹Immunopathology Laboratory, Department of Oncology-Pathology, Cancercentrum Karolinska (CCK), Karolinska University Hospital Solna/Karolinska Institutet, Stockholm, Sweden

²Department of Pathology, Muhimbili University of Health and Allied Sciences (MUHAS), Dar es Salaam, Tanzania

³Department of Immunology, Semnan Medical University, Semnan, Iran

⁴Immune and Gene Therapy Lab., Cancercentrum Karolinska (CCK) Karolinska University Hospital Solna/Karolinska Institutet, Stockholm, Sweden

⁵Department of Surgery, MUHAS and Muhimbili National Hospital (MNH), Dar es Salaam, Tanzania

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Infectious Agents and Cancer 2008, 3:10doi:10.1186/1750-9378-3-10


Published:	30 June 2008

Abstract

Background

The association of the human herpesvirus-8/Kaposi's sarcoma (KS)-associated herpesvirus (HHV-8/KSHV) serology with various malignancies in Tanzania is not currently well established while previous studies were based on either PCR or immunofluorescence assays [IFA] but not with a sensitive enzyme-linked immunosorbent assay (ELISA). Selected archival diagnostic biopsies (n = 184) and sera from indigenous patients with KS (n = 120), non-KS tumors (n = 24) and non-neoplastic lesions (n = 40) at Muhimbili National Hospital (MNH), Tanzania, were evaluated by diagnostic histopathology, immunohistology [anti-HHV-8 latency-associated nuclear antigen (LANA)] and serology for HIV (ELISA) and HHV-8 (IFA and ELISA).

Results

About 66.3% (n = 122) cases including AIDS-associated Kaposi's sarcoma (AKS) (n = 93), reactive conditions (n = 28) and only one non-KS tumour were HIV positive. Endemic KS (EKS) patients were mostly males (96.3%, 26/27) who were less (69.9%, 65/93) predominant in AIDS-associated (AKS). A high (89%) percentage of patients with anti-HHV-8 antibodies was found in the cohort including the HIV positive (92%) cases, males (81.2%), KS patients (93%), non-KS tumors (92%), and reactive conditions (75%). All HHV-8 seronegative KS cases were nodular stage whereas both sera and corresponding biopsies from early stage KS were HHV-8+. Assay sensitivity, positive predictive value (PPV) and specificity were 98.6%, 93.5% and 16.7% for IFA and 93.5%, 98.6% and 50.0% for ELISA respectively.

Conclusion

HHV-8 seroprevalence at MNH appears high as expected among AKS cases and males but also in non-KS patients. ELISA showed a combination of high HHV-8 sensitivity as well as higher PPV and specificity than IFA which however, showed higher sensitivity. The apparent stage-dependent, inverted serum HHV-8 immunoreactivity supports a notion of viral immune-segregation during KS development. Routine HHV-8 screening should be considered particularly in patients at risk of KS and for selection of blood/organ donations.