Tissue viral DNA is associated with chronic allograft nephropathy

: Viral infections post‐renal transplant (Tx) impact on outcome. Increased rejection rates and decreased renal function secondary to acute CMV, EBV and HHV‐6 infections are well described. However, the clinical significance of a mere presence of these viruses on kidney tissue biopsy remains questionable. Thirty‐six kidney biopsies obtained from 17 renal transplants (five females) and two combined liver–kidney recipients (one female) were retrospectively evaluated. Age at Tx ranged from 1.7 to 17.2 yr (median = 7.4). Biopsies were performed as protocol biopsies or when renal function deteriorated, between 6 weeks and 11 yr post‐Tx (median = 1.2 yr). Immunosuppression included steroids and combination of tacrolimus/cyclosporin, mycophenolate mofetil/azathioprin and induction therapy. Fourteen patients received antiviral prophylaxis (ganciclovir/valganciclovir/acyclovir). Renal tissue was classified according to Banff ’97 criteria. Tissue CMV, EBV, HHV‐6 and HHV‐7 was analyzed by PCR. We used an estimation of GFR from average plasma Cystatin C (CysC) and slopes of 1/CysC to assess renal function. The 16/36 biopsies were positive for one virus; 5/36 biopsies were positive for two viruses. In the infected group, Banff ’97 scores for interstitial fibrosis (ci) and tubular degeneration/atrophy (ct) were significantly higher (p