Histologic and clinical findings in living donor allografts with long-term stable function

Protocol biopsy is an important strategy which assesses the histological changes that can occur in the renal allograft and adversely affect its outcome. We aimed to evaluate histological changes in long-term living donor transplants.

Elective biopsies were done for 120 live donor renal transplant recipients with well-functioning grafts and no rejection history at least 1 year or more after transplant. All patients had serum creatinine levels <2 mg/dl. The histopathological findings using the chronic allograft damage index score were correlated with different clinical and immunological parameters.

Chronic tubulointerstitial fibrosis was the most prevalent finding (85% of cases), mostly of mild degree. Normal biopsies were reported in only 7.5% of cases, whereas chronic cyclosporine nephrotoxicity was detected in 5.8% of biopsies. Posttransplant hypertension was significantly correlated with glomerulosclerosis, and posttransplant diabetes with glomerulosclerosis, mesangial matrix increase, tubular atrophy and interstitial fibrosis. The main risk factors associated with a high chronic allograft damage index score were DR mismatching, posttransplant diabetes and time of biopsy. All histopathological changes increased with advancing donor age and declining graft function.

Elective biopsies showed that histopathological findings do exist even with stable renal function that may pave the way for predicting long-term graft outcome.