Liver transplantation offers excellent results for children with end-stage liver disease, and efforts should be directed toward maintaining long-term graft health. We evaluate graft pathology in healthy pediatric transplant recipients with low-maintenance immunosuppressive medications to assess whether protocol biopsies are helpful for adapting immunosuppression and protecting long-term graft function. Liver biopsies were performed on 60 healthy pediatric liver transplant recipients, and histological findings were correlated with laboratory, serological, and radiological results. Fourteen patients (23%) were diagnosed with acute or early chronic rejection, and immunosuppressive medications were increased in these children. Liver function tests did not correlate with histological findings. The incidence of fibrosis was 36% in transplant recipients five or more years after liver transplantation. We observed an unexpectedly high prevalence of rejection and fibrosis in children with no laboratory abnormalities, which led to changes in their immunosuppressive medications. Scheduled biopsies appear to be useful in pediatric transplant recipients with low immunosuppressive medications for early detection of morphological changes in liver transplants. Further studies are needed to evaluate whether adaption of immunosuppression helps to reduce tissue damage and the incidence of allograft dysfunction in the long term.

The prevalence of DSA was 33% for group 1 and 68% for group 2. Antibodies were predominantly HLA class II. Values of mean fluorescence intensity were comparable in both groups. Only one of the DSA+ ve patients from group 1 exhibited preformed antibodies. In conclusion, pediatric patients with chronic rejection revealed a higher rate of de novo DSA, especially of HLA-class II DSA. Further studies are necessary to confirm these data with a larger pediatric cohort.