Outcomes of liver transplantation for mitochondrial respiratory chain disorder in children

Aim: Mitochondrial respiratory chain disorder (MRCD) can cause acute liver failure (ALF), which may necessitate liver transplantation (LT). However, MRCD is often difficult to diagnose before LT and the indications of LT are controversial due to the likelihood of progressive neurological disease. The present study further characterized the patient population and described the outcomes. Methods: Thirteen patients who underwent LT for MRCD from November 2005 to May 2020 were enrolled in this study. Results: Six of 13 MRCD patients were diagnosed with a mitochondrial inner membrane protein 17-related mitochondrial DNA depletion syndrome (MTDPS). Overall, nine survived with a median follow-up of 1.8 years (IQR, 1.3–5.1 years); four died within 2 years. In the long-term, seven survivors showed no progression of hypotonia after LT and attended a normal kindergarten or primary school. Neurological abnormalities were observed in two survivors, including vison loss related to Leber's hereditary optic neuropathy in one patient and psychomotor retardation related to Leigh syndrome in the other. Three non-survivors after LT were diagnosed with MTDPS and died of severe pulmonary hypertension, which had developed at 8, 9, and 18 months after LT (n=1 each). The remaining patient died of postoperative respiratory infection with respiratory syncytial virus. Conclusion: The long-term results support the performance of LT in patients with MRCD, although a genetic diagnosis is preferable for determining the accurate indications for LT in these patients. Furthermore, care should be taken to avoid complications due to mitochondrial dysfunction during the long-term follow-up.