Long-Term Amino Acid Homeostasis, Neurodevelopmental and Growth Profiles Following Liver Transplantation in Maple Syrup Urine Disease.

Abstract

Maple syrup urine disease (MSUD) is caused by the deficiency of branched-chain keto acid dehydrogenase (BCKAD) and, it is well described that BCKAD contributed by an allograft following liver transplantation (LT) phenotypically normalizes this inborn error of metabolism (IEM). There is, however, a paucity of data especially with regards to the neurodevelopmental aspects and catch-up growth profiles after LT in a resource-challenged setting. We present our series of children under 6 years of age who underwent LT for MSUD particularly focusing on their amino acid homeostasis, neurodevelopmental and somatic growth profiles. Of 580 consecutive pediatric LT (PLT) performed between January 2011 and December 2022, all children who underwent LT for MSUD were included for analysis. Data accrued included peri-LT details, pre- and post-LT metabolic profile, neurodevelopmental assessment, somatic growth evaluation, and long-term outcomes. Six children underwent LT for MSUD with a median age and weight at LT of 20.5 (IQR: 8-60) months and 10.1 (IQR: 6.7-15.8) kg, respectively. One explanted liver was used as a domino graft for Arginase deficiency. Median follow-up period was 52.5 (IQR: 27-94) months. None had vascular or biliary complications. Following LT, all children were started on an unrestricted protein diet and had normalization of BCAA levels. Post-LT height and weight improved by 1 SD but did not achieve the normal profile. None of the children had neuro-deterioration and have achieved new milestones. This is the first-report presenting the growth aspects, amino acid and neurodevelopmental profiles of children who underwent LT for MSUD within the socio-economic-cultural idiosyncrasies and constraints prevalent in our part of the world.