Introduction: Liver transplantation(LT) has become an alternative treatment for Inborn Errors of Metabolism(IEM). This approach can significantly improve quality of life of patients who suffer from severe disease manifestations and/or life-threatening metabolic decompensations despite medical management. The aim of this article was to report a single-center experience of pediatric liver transplantation for IEM.

Methods: 922 LT were performed from March 1993 to December 2021 at Garrahan Hospital in Buenos Aires. Medical records of 45 patients who suffered IEM younger than 18 years were analyzed. The variables measures were: patient demographics, indications, cirrhotics or non cirrhotics, graft type, survival, postoperative complications, growth and schooling.

Results: IEM represented 5% of the LT in 28 years. 45 LT were performed(25 females, 20 males) at a median age of 69 months(range 1-217 months). The median follow up time was 4.4 years (range 0.01- 23yr). LT indications were: cirrhosis complications(14), quality of life(23) and acute liver failure(8). Twenty-five were cirrhotic and 20 non cirrhotic in the explants. The cumulative 1, 5 and 10-year graft survival rates were 84%, 84% and 77% respectively. 23 LT were performed in IEM that affect intermediate metabolism (glycogen storage disease 8 MSUD 1, argininosuccinic aciduria 3, OTC deficiency 4, citrulinemia I 2, methylmalonic aciduria 2, tyrosinemia I 4) at a median age of 91 months(range 18- 210 months). The median follow up time was 2.4 years(range 0.01- 23yr). LT indication were: cirrhosis complications in 4, quality of life in 17 and 2 acute liver failure.8 IEM were cirrhotic in the explants. 2 combined liver–kidney transplantation was performed. Biliary and vascular complications were 35% and 22% respectively. Six had a liver tumor: 3 adenomas and 3 hepatocellular carcinoma. The cumulative 1,5 and 10 years graft survival rates were 96% , 87% and 87% respectively. If we take into account transplant periods before and after the implementation of PELD/MELD system to categorize patients by severity, we can distinguish two groups: LT before 2005 and those after. If we compare graft survival at 1, 5 and 10 years in LT globally in the pre-PELD/MELD era, this was 66, 94%, 58.87% and 52.69, respectively (N=372), after 2005 the graft survival was 81.37%, 5 years 72.10%, 66.6% (N=550). Survival before 2005 in IEM was 58%, 58%, and 33%, respectively, while after 2005 it was 93%, 93%, and 93%.

Conclusion: Liver transplantation improves the survival and quality of life in IEM. Short- and long-term survival in LT improved considerably with the implementation of the PELD/MELD System and this was more evident in the IEM group, although the follow-up intervals were shorter. The improvement in surgical techniques, immunosuppression regimens and supportive treatment may explain these differences. In the IEM group, experience in other centers and early indications for LT may explain the increased survival.