Long-term graft outcome is not necessarily affected by delayed onset of graft function and early acute rejection.

BACKGROUND: Both acute rejection episodes and delayed graft function (DGF) have been shown to be associated with decreased 1-year renal allograft survival. In our center, the incidence and the intensity of acute rejection episodes have been reduced by cyclosporine-based triple-drug therapy. We have also shown that DGF alone is not a risk factor for long-term graft survival. METHODS: We have now investigated whether an acute rejection episode together with DGF significantly effects long-term graft outcome. This study involved 862 first cadaveric renal allografts and 182 regrafts. RESULTS: The incidence of DGF was 33% after first transplants and 44% after retransplants. The overall incidence of acute rejection episodes was 23% in first grafts and 28% in regrafts. After first grafts, there were no statistically significant differences in graft survival rates and half-lives between the early graft function (EGF) and DGF groups with or without acute rejection. In regrafts, graft survival was significantly higher in the EGF group without acute rejection than in the DGF group with acute rejection. However, if all other causes except chronic rejection were censored, the half-life in the EGF group without acute rejection was 17.3 years in first grafts, and in the DGF group with acute rejection, that number was 11.5 years in first grafts; for regrafts, the half-life was 12.3 years and 6.1 years, respectively. CONCLUSIONS: Acute rejection together with DGF could contribute to initial damage to the graft, and this might lead to later chronic allograft failure. In our study, this effect was evident only in the case of retransplants.

Long-term consequences of different immunosuppressive regimens for renal allografts.

The long-term effects of four different immunosuppressive regimens on renal allografts have been investigated up to four years. A total of 128 recipients of first cadaveric renal allograft were randomized, after an initial induction period, to receive either triple drug therapy--i.e., (low-dose) cyclosporine, azathioprine, and methylprednisolone, or any possible combination of two drugs--i.e., Aza plus CsA, Aza plus MP, and CsA plus MP. The actual four-year graft survival rates for the triple therapy, Aza plus CsA, Aza plus MP, and CsA plus MP groups were 72%, 69%, 75%, and 59%, and patient survival rates were 78%, 81%, 81%, and 84%, respectively, with no significant differences. The cumulative number of chronic rejections up to 4 years was 0.09, 0.29, 0.25, and 0.34 per patient per group (P = ns), respectively. At 2, 3, and 4 years posttransplantation, the graft function was significantly worse in the Aza plus MP group compared with the triple therapy group (P < .05). Of the 98 patients who did not have type I or II diabetes at the time of transplantation, 17 developed posttransplantation diabetes mellitus or an abnormal glucose tolerance test within 2 years posttransplantation. All these patients had received steroids and none of the patients without steroids had these abnormalities. At two years the mean cholesterol level was highest in the Aza plus MP group, 6.8 mmol/L and lowest in the group receiving triple therapy, 5.8 mmol/L (P = ns). The use of (low-dose) CsA was not associated with lipid abnormalities or with disturbances in glucose metabolism. A protocol graft biopsy was performed at two years on all functioning kidneys, and the histological changes were scored blindly. No CsA-specific changes, except isometric vacuolation in tubuli, were found. Histological alterations characteristic of chronic rejection were expressed as "chronic allograft damage index." Chronic allograft damage index was lowest in the triple therapy group, 1.5, compared with the other groups, 3.2-4.3 (P = .01), indicating the least histopathological change in the triple therapy group. In conclusion, this long-term study did not show any serious cyclosporine-related side-effects when used in low dose in combination with two other drugs. Some side-effects, such as posttransplant diabetes mellitus and probably some lipid abnormalities, could rather be traced to a higher dose of steroids. Moreover, the triple drug therapy was more efficacious than any double drug regimen in the prevention of chronic histological changes in renal allografts.

Acute vascular rejection in renal transplantation--diagnosis and outcome.

Thirty episodes of histologically verified acute vascular rejection in kidney transplant recipients were studied. In 11 grafts the rejection was mainly vascular, whereas in 19 grafts a concomitant cellular rejection was seen. Histological features prognostic for bad outcome were glomerular necrosis and thrombi in the arteries and arterioles. Characteristic findings in transplant cytology, i.e., high number of monocytes and low number of lymphocytes and blast cells were noted prior to the onset of clinical signs of rejection, and this finding was also persisting throughout the rejection episode. The numbers of lymphocytes and blast cells were significantly lower in grafts with a pure vascular rejection than in grafts with a concomitant cellular rejection. Vascular rejection was reversible in 15 cases. As rescue therapy plasmapheresis and added immunosuppression were often successful.