title: Association of HHV-6 and HHV-7 reactivation with the development of chronic allograft nephropathy.
abstract: BACKGROUND
  The long-term effect of HHV-6 and HHV-7 infections on chronic allograft nephropathy (CAN) development after renal transplantation is uncertain.
  
  
  OBJECTIVE
  To determine HHV-6 and HHV-7 reactivation during the post-transplantation period and to evaluate its effect on CAN development in renal transplant patients.
  
  
  METHODS
  Eighty-one renal allograft recipients (28 with CAN, 53 with normal transplant function) were studied to determine the frequency of HHV-6 and HHV-7 reactivation during 36.4+/-7.8 months after renal transplantation using nested PCR. HHV-6 variants were identified using restriction endonuclease analysis. Patients were monitored for the development of CAN.
  
  
  RESULTS
  The frequency of HHV-6 and/or HHV-7 plasma DNA was significantly higher in CAN patients (25/28, 89.3%) compared to control patients (15/50, 30.0%, p=0.0001). CAN patients also had an increased incidence of dual active infections (20/25, 80% and 2/15, 13.3%, p=0.007, respectively). In all 34 HHV-6 positive cases, the HHV-6B variant was identified. The presence of HHV-7 DNA in plasma preceded the presence of HHV-6 DNA. Early development of CAN and graft loss was detected only in patients with simultaneous HHV-6 and HHV-7 plasma DNA.
  
  
  CONCLUSIONS
  Reactivation of HHV-6 and HHV-7 in renal graft recipients is a risk factor for CAN development. The presence of concurrent HHV-6 and HHV-7 DNA in the plasma is an unfavorable prognostic factor.
authors.affiliation: August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, Ratsupites St. 5, LV-1067 Riga, Latvia. scapenko@latnet.lv
authors.forename: S
authors.initials: S
authors.lastname: Chapenko
authors.forename: I
authors.initials: I
authors.lastname: Folkmane
authors.forename: I
authors.initials: I
authors.lastname: Ziedina
authors.forename: M
authors.initials: M
authors.lastname: Chistyakovs
authors.forename: R
authors.initials: R
authors.lastname: Rozentals
authors.forename: A
authors.initials: A
authors.lastname: Krumina
authors.forename: M
authors.initials: M
authors.lastname: Murovska
mesh_terms: D000328:Adult; D005260:Female; D015654:Herpesvirus 6, Human / Q000502:physiology*; D016199:Herpesvirus 7, Human / Q000502:physiology*; D006801:Humans; D015994:Incidence; D007674:Kidney Diseases / Q000453:epidemiology* / Q000209:etiology; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012307:Risk Factors; D019349:Roseolovirus Infections / Q000821:virology*; D014184:Transplantation, Homologous / Q000009:adverse effects*; D014775:Virus Activation