Surveillance of viral infections in renal transplant recipients - A prospective observational study

Background: There has been significant advancement in the field of renal transplantation in the last few decades. However, the long-term graft survival has not dramatically increased. Among all the infections, viral infections continue to be a major contributor to graft failure as well as severe mortality and morbidity in renal transplant recipients. Materials and Methods: It was a prospective, nonrandomized, observational study of the duration of 1 year that was conducted in live donor renal transplant recipients (n = 96). Blood samples were collected from all live renal allograft recipients at specified intervals and investigated for the viral infections. Glomerular filtration rate (GFR) and tacrolimus levels were measured at follow-ups. Results: Prior to renal transplant, the hepatitis C prevalence was the highest accounting for viral infection in 7.3% of the total study population. The study had pretransplant cytomegalovirus (CMV) and BK virus (BKV) infection rates of 1.04% each. CMV infection had the highest incidence rate occurring in 29.1% of the total population posttransplantation. There was significant incidence of CMV infection (CMV+) after rejection (P = 0.016). The incidence of BKV infection in our study through 1 year was 8.3%. The incidence of CMV infection correlated well with mean tacrolimus trough level of 10.58 +/- 1.25 ng/mL. The mean estimated GFR (eGFR) at 12 months in infected patients was 65.12 +/- 5.31 ml/min/1.73 m2 which was significantly lower compared to controls which was 75.53 +/- 2.24 ml/min/1.73 m2 though they had comparable mean eGFR at baseline (P = 0.008). Conclusions: Hepatitis C was the dominant infection among all pretransplant viral infections. The highest incidence of CMV and BKV infection was after 6 months' posttransplant. Rejection was associated with CMV infection. All patients with BKV viremia had viruria. High level of tacrolimus was associated with CMV incidence. CMV infection was associated with lower eGFR at 1-year postrenal transplant.