Longitudinal analysis of human herpesvirus-8 DNA and antibodies in an Italian allogeneic stem cell transplant recipient

Abstract

Background Changes of HHV-8 antibody reactivity and intermittent detection of HHV-8 DNA have been observed in subjects with Kaposis's Sarcoma and/or HIV infection. Little is known about the longitudinal dynamics of HHV-8 DNA and antibody response in allografted stem cell transplant (SCT) patients without Kaposis's Sarcoma. Objectives To report the natural history of a HHV-8 seropositive patient with chronic lymphocytic leukemia who developed an active HHV-8 infection after SCT. Study design HHV-8 antibodies were measured by IFA and ELISA assays. HHV-8 DNA was detected by real-time PCR quantitative assay in serum and peripheral blood leukocytes (PBL). Results Twenty-two out of 26 (85%) serum samples had detectable HHV-8 antibodies: 21/26 (80%) samples were positive by both IFA and ELISA assays, while 1 sample was ELISA positive-IFA negative. The remaining 4 samples (15%) were negative by both assays. Five out of 6 (83%) serum-PBL samples pairs had detectable HHV-8 DNA: a median of 934 genomes/ml (range 254–6316 genomes/ml) in the serum and a median of 10,000 genomes/10 5 (range 1472–93,460 gen/10 5) in PBL. An active HHV-8 infection occurred early within the first 30 days after the transplant, extended up to day +180 and occurred without evidence of HHV-8-related neoplastic or non neoplastic diseases. Conclusions This study provides evidence that a patient infected with HHV-8 before SCT can be either intermittently HHV-8 DNA-positive and/or seropositive for HHV-8 after SCT. A high and persistent HHV-8 replication may be ongoing even in the absence of overt HHV-8-associated diseases.