| Abstract: | Maple syrup urine disease (MSUD) is an autosomal recessive disease associated withhigh levels of branched-chain amino acids. Children with MSUD can present severeneurological damage, but liver transplantation (LT) allows the patient to resume anormal diet and avoid further neurological damage. The use of living related donorshas been controversial because parents are obligatory heterozygotes. We report a caseof a 2-year-old child with MSUD who underwent a living donor LT. The donor was thepatient''s mother, and his liver was then used as a domino graft. The postoperativecourse was uneventful in all three subjects. DNA analysis performed after thetransplantation (sequencing of the coding regions of BCKDHA,BCKDHB, and DBT genes) showed that the MSUDpatient was heterozygous for a pathogenic mutation in the BCKDHBgene. This mutation was not found in his mother, who is an obligatory carrier forMSUD according to the family history and, as expected, presented both normal clinicalphenotype and levels of branched-chain amino acids. In conclusion, our data suggestthat the use of a related donor in LT for MSUD was effective, and the liver of theMSUD patient was successfully used in domino transplantation. Routine donorgenotyping may not be feasible, because the test is not widely available, and, mostimportantly, the disease is associated with both the presence of allelic and locusheterogeneity. Further studies with this population of patients are required toexpand the use of related donors in MSUD. |
