Long-term outcome after pediatric lung and heart-lung transplantation

Background: In total number of transplants and number of experienced centers, pediatric lung (LTx) and heart-lung transplantation (HLTx) lags behind adult LTx and HLTx. Therefore, long-term outcome information is available mainly from worldwide cumulative data (ISHLT registry). However, there may be clinically and therapeutically relevant outcome differences which are masked by cumulative evaluation. Therefore, we searched for mortality risk factors after pediatric LTx and HLTx with attention focused on regional and center-specific features with regard to long-term outcome. Methods: We evaluated all pediatric lung and heart-lung recipients (<18 years old at Tx) who were transplanted at our center between 3/1992 and 10/2001. Special attention was paid to recipient age and gender, donor-recipient interactions, indication for Tx, rejection treatment and post-Tx morbidity. Results: Up until 10/2001 a total of 21 pediatric patients (11 girls, 10 boys) with age at Tx of 14.4 ± 3.5 years underwent LTx (n = 10) or HLTx (n = 11). At the time of evaluation (10/2004) the first patient who was transplanted during the evaluation period (still alive) had reached a post-Tx time of 12.2 years, whereas the last, also still alive, had a post-Tx time of over 3 years. Survival rates at 3 and 5 years after transplantation were 66.0 ± 10.5% and 50.0 ± 11.3%, respectively. In those who survived the first post-Tx year, the 3 and 5 year survival rates were 92.9 ± 6.9% and 70.1 ± 12.6%, respectively. Survival was better in girls (age 15.4 ± 2.5 years) than in boys (age 13 ± 4.2 years) and survival was also better after HLTx than after LTx, but the differences were not significant. The most frequent indications for pediatric DLTx und HLTx were congenital systemic to pulmonary shunts (Eisenmenger syndrome) and cystic fibrosis (mucoviscidosis), which represented 66.7% of all indications. Bronchiolitis obliterans (BO) was diagnosed in all patients who died beyond the first 6 months after Tx and was also the main cause of death in 85.7% of these patients. All BO patients had had recurrent acute rejections, 44.4% were cytomegalovirus (CMV) mismatched and 89% had at least one clinically manifested CMV infection. Among those who survived >5 years after Tx, 71.4% had both donor and recipient CMV negative status (D-/R-). None of the CMV D-/R- patients died after the first 6 post-Tx months (mean survival at present 7.9 ± 2.2 years) and none of them has BO, although their post-Tx times range between 5 and 12 years. Conclusions: Our pediatric patients showed above average life expectancy after DLTx and HLTx. The good long-term survival time after HLTx (longest time so far 12.2 years) proves that, with adequate surgical experience, this procedure may be very successful. After the first post-Tx year, BO was the main cause of death and CMV infection appears to be a major cause of BO. Patients with CMV D-/R- showed excellent long-term outcome, even after acute rejection episodes during the early post-Tx period.