Protocol Biopsies in High-risk Renal Transplant Recipients

This will be a prospective study undertaken at the Renal Transplant Unit of Hospital of Clinics of Porto Alegre. In addition to the routine evaluation commonly carried-out at this post-transplant period, protocol biopsies will be performed at the 10th-week post-transplantation in high-risk transplant recipients. Biopsy fragments will be evaluated for tissue immune aggression (mainly cellular and antibody-mediated rejections) and other conditions such as infections, particularly polyomavirus and cytomegalovirus and medication toxicities. The presence of donor-specific antibodies and graft-damaging infectious agents will also be searched in the peripheral blood at the time of biopsy.One hundred patients will be randomized to a protocol biopsy and noninvasive assessment or only for noninvasive assessment. The hypothesis of the study is that biopsies will lead to treatments that may allow better outcomes of renal transplants, related to lowering the progression of subclinical aggressions, avoiding or delaying graft loss and preserving or decreasing the rate of loss of the glomerular filtration rate. Therefore, this strategy has the possibility of reaching clinical practice routine and thus contribute positively to the management of renal transplant patients.