Histological features with clinical impact in chronic allograft nephropathy: review of 66 cases

The histological features of chronic allograft nephropathy (CAN) are variable, since it is related to multiple donor and recipient factors. The main histological parameters in CAN are interstitial fibrosis, tubular atrophy, chronic vasculopathy and glomerulosclerosis. There have been many attempts to relate chronic deterioration of renal function with histologic features.

We reviewed 66 kidney transplant patients (43 men/23 women) with renal failure 6 months after transplant. The clinical data included donor and recipient age, cold ischemia time, delayed graft function (DGF), creatinine clearance, proteinuria, HLA compatibility, CMV infection, cholesterol levels, diastolic and systolic blood pressure. Banff criteria were used to grade histological parameters. The relation between clinical and histological data were analyzed using chi square, Student t, Mann Whitney and Kruskal-Wallis tests as appropriate. The cumulative graft and patient survival rates were calculated by the Kaplan-Meier method.

The survival rate of patients with creatinine clearances >3 mg/dL at the time of the biopsy was worse than that of patients with creatinine <3 mg/dL (P =.001; log rank 20.1). We found an association between the grade of arteriosclerosis and the diastolic blood pressure (P =.017). The creatinine level was greater among patients with tabulitis than those without tubulitis (P =.06). In addition to our results we review the literature especially related to the histological feature of CAN in an attempt to detect histological findings predictive of the long term outcome of kidney allografts.