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Abstract Background Human herpesvirus 8 (HHV-8), the aetiological agent of Kaposi’s sarcoma (KS), multicentric Castleman’s disease (MCD), and primary effusion lymphoma (PEL) is rare in Australia, but endemic in Sub-Saharan Africa, parts of South-east Asia and Oceania. While the treatment of external KS lesions can be monitored by clinical observation, the internal lesions of KS, MCD and PEL require extensive and expensive internal imaging, or autopsy. In patients with MCD and PEL, if HHV-8 viraemia is not reduced quickly, ~50% die within 24 months. HHV-8 qPCR is a valuable tool for monitoring HHV-8 viraemia, but is not available in many parts of the world, including those with high prevalence of KS and HHV-8. Methods A new molecular facility with stringent three-phase workflow was established, adhering to NPAAC and CLSI guidelines. Three fully validated quantitative assays were developed: two for detection and quantification of HHV-8; one for GAPDH, necessary for normalisation of viral loads in tissue and peripheral blood. Results The HHV-8 ORF73 and ORF26 qPCR assays were 100% specific. All qPCR assays, displayed a broad dynamic range (102 to 1010 copies/μL TE Buffer) with a limit of detection of 4.85x103, 5.61x102, and 2.59x102 copies/μL TE Buffer and a limit of quantification of 4.85x103, 3.01x102, and 1.38x102 copies/μL TE Buffer for HHV-8 ORF73, HHV-8 ORF26, and GAPDH respectively. The assays were tested on a panel of 35 KS biopsies from Queensland. All were HHV-8 qPCR positive with average viral load of 2.96x105 HHV-8 copies/μL DNA extract (range: 4.37x103 to 1.47x106 copies/μL DNA extract): When normalised these equate to an average viral load of 2.44x104 HHV-8 copies/103 cells (range: 2.20x102 to 7.38x105 HHV-8 copies/103 cells). Conclusions These are the first fully optimised, validated and MIQE compliant HHV-8 qPCR assays established in Australia. They worked well for qualitative detection of HHV-8 in archival tissue, and are well-suited for quantitative detection in whole blood. They are now available for research, for clinical diagnosis of HHV-8 infection, and for monitoring treatment efficacy.

Storing saliva for nucleic acid diagnostics is problematic in resource-constrained settings. DNA Genotek's OMNIgene™ · DISCOVER kit aims to stabilise microbial DNA at room temperature. We evaluate this for long-term storage, determining DNA quantity/purity and human herpesvirus 8 (HHV-8) load as indicator. Viral loads and DNA degradation were assayed over 14 months in HHV-8–negative saliva spiked with cell-associated and cell-free virus and saliva collected fresh frozen and into kits from 10 HIV-positive patients. Viral loads remained constant for 6–9 months, yielding high quantities of DNA: subsequent losses were ≤48%. Patient samples, frozen or kit stored, produced pure DNA of comparable concentration. Higher HHV-8 detection in frozen saliva resulted from losses during ethanol precipitation using kits. After 14 months, DNA degradation was significant in frozen saliva, but that in kits had integrity similar to fresh samples. Storing frozen saliva is detrimental. This kit is well suited for collection, long-term storage, and assay of viral DNA in resource-constrained settings. [ABSTRACT FROM AUTHOR]

Abstract: Background: Kaposi's sarcoma (KS) continues to be the most common human immunodeficiency virus (HIV)-associated neoplasm with considerable morbidity and mortality. While lesions normally resolve upon initiation of antiretroviral therapy (ART), recrudescence or unmasking of KS lesions may occur as part of immune reconstitution inflammatory syndrome (IRIS). Treatment of unmasking KS-IRIS is not yet standardised. Objectives: To report the successful treatment of a patient with fulminating mucocutaneous unmasking KS-IRIS by maintaining ART and using pegylated liposomal doxorubicin (PLD). Study design: The patient, a 39-year-old HIV-positive male with no previous history of KS presented with a 2-week history of cutaneous and oral KS lesions that had disseminated rapidly over the preceding 4 days. The KS lesions appeared 8 weeks after recommencing ART. At the time of this presentation, his CD4+ count was 742cells/mm3 with a HIV viral load <400copies/ml. ART was maintained and treatment with PLD commenced. Results: Despite the rapid dissemination of KS lesions, virus was undetectable in plasma. In a late-stage vasoformative lesion, immunohistochemistry (IHC) for human herpesvirus 8 (HHV-8) antigen was light and diffuse, with stippled deposits within endothelial cell nuclei. Virus extracted from the lesion was HHV-8 subtype A. The patient responded well to PLD, relapsed a year later, but after further PLD, has remained well for the following 5 years. Conclusion: Despite the absence of HHV-8 viraemia, this is clearly a case of unmasking KS-IRIS. It demonstrates that this entity can be successfully treated by maintaining ART and administering PLD. [Copyright &y& Elsevier]