Kidney graft loss in children: implications for program development.

BACKGROUND: Graft survival in children who undergo kidney transplantation is lower than that in adults. The objective of the study was to review the experience of the first 22 years of operation of the regional pediatric kidney transplantation unit for Atlantic Canada, based at the IWK-Grace Health Centre, Halifax, and to use the results to improve graft survival. METHODS: All cases of kidney transplantation performed at the centre from 1971 to 1992 were reviewed and the data compiled with the use of a predetermined database outline. Data for first transplants were analysed and compared with those in North American databases. Of the 40 graft failures, 19 (48%) occurred within the first 3 months after transplantation, a rate similar to that at other centres. The overall survival rates tended to be slightly lower than those of international databases. The introduction of cyclosporine A as an immunosuppressant, in 1985, did not provide the expected marked improvement in survival. Infection frequently accompanied acute rejection, and there was a delay in treatment of infections and rejection after discharge home. On the basis of these preliminary findings, several program changes were made: 1) a sequential immunosuppression protocol was implemented, 2) the intensity of the medical surveillance was increased for the first 3 months after transplantation, with aggressive treatment of infections and rejections, 3) a dedicated pediatric transplantation team was established as a subset of the adult team and 4) pediatric-specific selection criteria for cadaver donors were formulated. After these changes were implemented, data were collected and analysed up to June 30, 1997. RESULTS: Graft survival rates at 1, 2 and 5 years improved dramatically. After the beginning of 1993, there were only 2 graft losses among 22 transplants. Only one of these occurred in the first 3 months, and it was due to recurrent disease. Twenty-four rejection episodes occurred (10 in the first 3 months after transplantation), but all were reversed easily with high-dose steroid therapy. INTERPRETATION: Sequential immunosuppression with close medical surveillance and early aggressive treatment of infection and rejection contribute to a marked improvement in kidney graft survival in children.

The interaction of the calcium channel blockers verapamil and nifedipine with cyclosporin A in pediatric renal transplant patients.

The elimination of cyclosporin A was assessed in eight pediatric renal transplant patients who received calcium channel blockers concomitantly with their immunosuppressive therapy. In three children, verapamil decreased the rate of elimination of cyclosporin A. In five children who received nifedipine, cyclosporin A elimination was also impaired, which contrasts with the reports in adult patients indicating that this calcium channel blocker has no effect on cyclosporin A elimination. When both calcium channel blockers were used on separate occasions in the same patient, nifedipine was less potent than verapamil in depressing cyclosporin A elimination. Although the number of subjects studied is small, these results likely indicate that nifedipine, as well as other calcium channel blocking drugs, must be used with caution in pediatric renal transplant patients.