LYMPHOTROPIC HERPESVIRUSES IN ALLOGENEIC BONE-MARROW TRANSPLANTATION

Human herpesvirus-6 (HHV-B), human herpesvirus-7 (HHV-7), Epstein-Barr virus (EBV), and human cytomegalovirus (CMV) DNA were repeatedly assa yed in peripheral blood leukocytes from 37 allogeneic bone marrow tran splant (BMT) patients by polymerase chain reaction. Before BMT, HHV-B DNA was detected in 8 (22%) patients. HHV-7, EBV, and CMV DNA were det ected in 21 (57%), 10 (27%), and 1 (3%) patient, respectively. After B MT, HHV-6 DNA was detected in 26 (70%), HHV-7 in 21 (57%), EBV in 28 ( 76%), and CMV in 21 (57%) patients. Thirty-two (87%) patients were pos itive with more than one virus. HHV-6, HHV-7, and EBV DNA were found e arlier than CMV DNA in most patients after BMT, The proportions of HHV -6-positive samples during the first 3 months after BMT were higher in the patients with either delayed granulocyte engraftment (P = .04, Fi sher's exact test) or delayed platelet engraftment (P = .001, Fisher's exact test). The HHV-6 DNA in samples from the patients with delayed engraftment was confirmed to be variant B. The detection of any lympho tropic herpesvirus was not related to the development of acute graft-v ersus-host disease (aGVHD). High-dose acyclovir (ACV) prophylaxis sign ificantly (P < .01) reduced the proportion of HHV-6-positive samples a nd tended to lower HHV-6 DNA levels (P = .06). Our data indicate that HHV-6 variant B can inhibit marrow engraftment and that high-dose ACV may be beneficial to engraftment after BMT by preventing HHV-6 reactiv ation. No relation between the proportions of HHV-7-, EBV-, and CMV-po sitive samples in the first 3 months and engraftment or aGVHD was foun d. (C) 1996 by The American Society of Hematology.