Analysis of clinical variables associated with tolerance in pediatric liver transplant recipients

Tolerance has been defined as stable graft function off IMS. We reviewed the data of 369 pediatric liver transplant patients to examine demographic differences that may have a PV of pediatric LT tolerance. Of the 369 patients, 280 patients were stable with detectable blood levels of IMS agents and with good graft function without biopsy proven REJ > 1 yr posttransplantation, 18 patients were noted to be TOL off EMS, 27 patients were taking MIS with drug levels below detectable range by standard laboratory parameters, and 44 patients developed one or more episodes of biopsy proven acute or chronic REJ > 1 yr post-transplantation. Variables, including percentage of biliary atresia, type of transplanted organ, history of EBV infection, patient and donor gender, and ABO blood type mismatch between recipient and donor did not have PV of tolerance. Average age in years was 1.37 +/- 1.53 (0.3-4.9) for TOL, 1.14 +/- 0.89 (0.4-3.1) for MIS and 3.35 +/- 4.45 (0.3-16) for REJ. Age difference of TOL/MIS vs. REJ was significant (p = 0.002) and TOL vs. REJ was significant (0.01). Age at the time of transplantation is an important predictor in the development of pediatric LT tolerance.