Two-hour post-dose cyclosporin A levels in adolescent renal transplant recipients in the late post-transplant period

Although the success of renal transplantation is closely linked to the immunosuppression provided by cyclosporin A (CsA), the best way to monitor the blood levels of CsA is still not clear. Trough CsA levels (C-0) are commonly used, but the 2-h post-dose CsA levels (C-2) are reported to correlate better with area under the curve. The aim of this study was to evaluate the correlation of C-2 levels with allograft function in adolescent renal transplant recipients in the late post-transplant period (6 months after transplantation) compared with C-0 levels. The data of 17 adolescent renal transplant recipients (12 males, 5 females) were evaluated retrospectively. The mean age at the time of transplantation was 15.212+/-2.918 years and the mean follow-up period was 53.172+/-34.090 months. C-0 levels correlated with oral CsA and diltiazem doses, while C-2 levels exhibited no correlation. When C-2 levels were classified as 0-400, 401-800, and 801-1200 ng/ml, no statistically significant difference was found between these groups with respect to glomerular filtration rate (P=0.830). Although 82% of the patients had C-2 beneath the therapeutic level (<800 ng/ml), none had an acute rejection episode. In conclusion, optimum C-2 levels could be different from levels in the adult population. Furthermore, the correlation of C-2 levels with CsA dose seems to be weaker than in the adult population. Thus, further studies are needed to determine a more reliable predictor for CsA dose monitoring and target blood CsA levels in adolescent patients.