Absorption phase cyclosporine (C(2h)) monitoring in the first weeks after pediatric renal transplantation.

Cyclosporine (CsA) monitoring using abbreviated area under the curve or 2-h blood concentration (C(2h))has been shown to predict total drug exposure in adult renal transplantation. However, pediatric experience is limited. Since 1998, we have monitored C(2h) in 45 children (age 10.6+4.7 years) during the first 6 weeks after transplantation. In 22 a 4-h CsA profile (AUC(0-4h)) was available and C(2h) in the remaining 23 patients. In addition CsA profiles from 24 children transplanted before 1998 were used to calculate the correlation between single time points and AUC(0-4h). The best correlation between AUC(0-4h) and a single time point was seen with C(2h) (r(2)=0.89). Coh did not predict AUC(0-4h) reliably (r(2)=0.27). C(2h) showed the lowest prediction error (10.0+9.6%).No dependency on age could be detected. In the first 3 months following transplantation, rejection was ob-served in 9 of 45 patients (20%). Glomerular filtration rate remained stable within the first 5 years after trans-plantation. In conclusion, in the early phase after renal transplantation, C(2h) can be used to predict drug exposure within the whole pediatric age group and should be evaluated in prospective trials.