Association of human herpesvirus 7 with cytomegalovirus disease in renal transplant recipients

Background. Recent studies have linked human herpesviruses 6 (HHV-6) and 7 (HHV-7) with posttransplant cytomegalovirus (CMV) disease. Methods. Thirty-seven renal transplant recipients were monitored weekly for CMV, HHV-6, and HHV-7 DNA and serological responses for 12 weeks after tra nsplantation. Plasma CMV load and the occurrence of CMV disease was related to HHV-6 and -7 detection. Results. CMV disease was identified in 12 patients. In a logistic regressio n analysis, factors significantly associated with CMV disease were the dete ction of HHV-7 DNA in peripheral blood leucocytes and donor-recipient CMV s erostatus. Patients with detectable HHV-7 DNA had significantly higher peak plasma CMV loads (P=0.01). Conclusions. An association was found between HHV-7, but not HHV-6, DNA det ection and CMV disease, suggesting a possible role of HHV-7 in its pathogen esis.