Introduction

Pediatric liver transplant recipients are exposed to prolonged immunosuppression, increasing the risk of complications. Pediatric data on the efficacy and safety of immunosuppression minimization to undetectable tacrolimus trough levels remain limited. We report our center’s experience with immunosuppression minimization in pediatric liver transplant recipients

Methods

We retrospectively reviewed liver transplant recipients followed between 2014 and 2024 who underwent at least one surveillance liver biopsy. Patient, graft, and biochemical factors associated with successful versus failed immunosuppression minimization were analyzed.

Results

Of 70 patients, 31 (44%) initiated minimization. Among these, 20 (64%) were female, 23 (74%) received deceased donor grafts, and 19 (61%) were transplanted in infancy. Biliary atresia was the most common indication 15 (48%).

Of 30 children with follow-up data available, 20 (67%) achieved successful minimization; 10 (33%) failed. Median ALT at minimization was significantly lower in the successful 18 (IQR15-21) compared to 23 (20-26) those who failed, (p=0.01). Age, sex, time since transplant, graft type, ABO compatibility, transplant indication did not predict minimization success (Table 1)

Among the 20 successfully minimized, 14 remained minimized at a median follow-up period of 6.9 years (IQR 3.1,10). Six patients required immunosuppression escalation at a median of 5.7 years (IQR:4.6,6.9), due to repeat surveillance biopsy findings (n=4) or elevated liver enzymes (n=2).

Conclusion

Approximately half of eligible pediatric liver transplant recipients remained successfully minimized at a median of 6.9 years supporting the durability of immunosuppression minimization in carefully selected pediatric patients. Lower ALT at the time of surveillance biopsy predicted successful minimization.