Liver Transplantation for Propionic Acidemia: Evidence From a Systematic Review and Meta-analysis

The worldwide experience of liver transplantation (LT) in the treatment of propionic acidemia (PA) remains limited and fragmented. This review aims to provide a comprehensive and quantitative understanding of posttransplant clinical outcomes in PA patients.

MEDLINE, Embase, and the Cochrane Library databases were searched for studies focusing on PA patients who underwent LT. The pooled estimate rates and 95% confidence intervals (CIs) were calculated using a random-effects model with Freeman-Tukey double arcsine transformation.

Twenty-one studies involving 70 individuals were included. The pooled estimate rates were 0.95 (95% CI, 0.80-1.00) for patient survival and 0.91 (95% CI, 0.72-1.00) for allograft survival. The pooled estimate rates were 0.20 (95% CI, 0.05-0.39) for rejection, 0.08 (95% CI, 0.00-0.21) for hepatic artery thrombosis, 0.14 (95% CI, 0.00-0.37) for cytomegalovirus/Epstein-Barr virus infection, and 0.03 (95% CI, 0.00-0.15) for biliary complications. The pooled estimate rates were 0.98 (95% CI, 0.88-1.00) for metabolic stability, 1.00 (95% CI, 0.79-1.00) for reversal of preexisting cardiomyopathy, and 0.97 (95% CI, 0.78-1.00) for improvement of neurodevelopmental delay. A large proportion of patients achieved liberalization of protein intake posttransplant (pooled estimate rate 0.66 [95% CI, 0.35-0.93]).

Despite the risk of transplant-related complications, LT is a viable therapeutic option in PA patients with satisfactory survival rates and clinical outcomes. Given the diversity in neurological assessment methods and the inconsistency in the achievement of dietary protein liberalization across different studies, consensus on neurological evaluation methods and posttransplant protein intake is necessary. Longer-term clinical outcomes of LT for PA warrants further investigation.