Article

Subclinical Inflammation and Chronic Renal Allograft Injury in a Randomized Trial on Steroid Avoidance in Pediatric Kidney Transplantation.

The BIOMARC Program for Personalized Medicine, California Pacific Medical Center Research Institute, Sutter Health Care, San Francisco, California, USA Department of Surgery, Stanford University Medical School, Stanford, CA, USA Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA Division of Pediatric Nephrology, Mattel Children's Hospital UCLA, Los Angeles, CA, USA Division of Pediatric Nephrology, University of Florida College of Medicine, Gainesville, FL, USA Department of Pediatrics, Harvard Medical School, Children's Hospital Boston, Boston, MA, USA Department of Pediatrics, University of California San Francisco (UCSF) Medical Center, San Francisco, CA, USA.
American Journal of Transplantation (Impact Factor: 6.19). 06/2012; 12(10):2730-2743. DOI: 10.1111/j.1600-6143.2012.04144.x
Source: PubMed

ABSTRACT Steroid avoidance is safe and effective in children receiving kidney transplants in terms of graft function and survival, but the effects on allograft histology are unknown. In this multicenter trial, 130 pediatric renal transplant recipients were randomized to steroid-free (SF; n = 60) or steroid-based (SB; n = 70) immunosuppression, and underwent renal allograft biopsies at the time of graft dysfunction and per protocol at implantation and 6, 12 and 24 months after transplantation. Clinical follow-up was 3 years posttransplant. Subclinical acute rejection was present in 10.6% SF versus 11.3% SB biopsies at 6 months (p = 0.91), 0% SF versus 4.3% SB biopsies at 1 year (p = 0.21) and 0% versus 4.8% at 2 years (p = 0.20). Clinical acute rejection was present in 13.3% SF and 11.4% SB patients by 1 year (p = 0.74) and in 16.7% SF and 17.1% SB patients by 3 years (p = 0.94) after transplantation. The cumulative incidence of antibody-mediated rejection was 6.7% in SF and 2.9% in SB by 3 years after transplantation (p = 0.30). There was a significant increase in chronic histological damage over time (p < 0.001), without difference between SF and SB patients. Smaller recipient size and higher donor age were the main risk factors for chronic histological injury in posttransplant biopsies.

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