The Histology of Solitary Renal Allografts at 1 and 5 Years After Transplantation

• Published in: American journal of transplantation Vol. 11; no. 4; pp. 698 - 707
• Main Authors: Stegall, M. D., Park, W. D., Larson, T. S., Gloor, J. M., Cornell, L. D., Sethi, S., Dean, P. G., Prieto, M., Amer, H., Textor, S., Schwab, T., Cosio, F. G.
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01-04-2011; Wiley
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Biological and medical sciences; Biopsy; Disease Progression; Female; Fibrosis; Fibrosis - pathology; Graft Rejection - pathology; Humans; Kidney Diseases - pathology; Kidney Transplantation; long‐term outcomes; Male; Medical sciences; Middle Aged; protocol renal allograft biopsies; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the urinary system; Time Factors; Tissue Donors; Transplantation, Homologous; Young Adult; Prognosis; Histology; Homotransplantation; Long term; Kidney; Anatomic pathology; Treatment; Urinary system; Biopsy; Surgery; Fibrosis; Graft; Evolution; long-term outcomes; protocol renal allograft biopsies; Kidney transplantation
• ISSN: 1600-6135; 1600-6143
• DOI: 10.1111/j.1600-6143.2010.03312.x

Previous studies suggest that the majority of renal allografts are affected by progressive, severe chronic histologic injury, yet studies using current protocols are lacking. The goal of this study was to examine the prevalence and progression of histologic changes using protocol allograft biopsies at 1 and 5 years after solitary kidney transplantation in patients transplanted between 1998 and 2004. Chronic histologic changes generally were mild at both 1 and 5 years and were similar in deceased and living donor kidneys. The overall prevalence of moderate or severe fibrosis was 13% (60/447) at 1 year and 17% (60/343) at 5 years. In a subgroup of 296 patients who underwent both 1‐ and 5‐year biopsies, mild fibrosis present at 1 year progressed to more severe forms at 5 years in 23% of allografts. The prevalence of moderate or severe arteriolar hyalinosis was similar in tacrolimus and calcineurin inhibitor‐free immunosuppression. These results in the recent era of transplantation demonstrate fewer, less severe and less progressive chronic histologic changes in the first 5 years after transplantation than previously reported.
This study of protocol renal allograft biopsies suggests that chronic histologic changes at 5 years are less severe than previously reported, and that mild fibrosis present at 1 year does not commonly progress to more severe forms. See editorial by Brouard et al on page 647.