Liver regeneration after split liver transplantation

BACKGROUND: The number of split liver transplantations (SLT) has increased in the last 5 years. Regeneration after the loss of hepatic tissue is a fundamental response to liver injury. Because partial-liver grafts may not be an optimal size for recipients, the purpose of this study was to investigate the regeneration of graft liver after SLT. METHODS: Four recipients have undergone SLT at our hospital since 2002. The graft liver volume (GLV) in the postoperative day ( POD) was measured by computed tomography (CT) and the serum levels of aspartate amino-transferase (AST) , alanine aminotransferase (ALT) , total bilirubin ( TB ), prealbumin ( PA ) and albumin ( ALB ) were monitored. The GLV at different postoperative times was compared to the recipient’ s standard liver volume ( SLV) and the liver volume regeneration ratio ( LVRR) was calculated. In order to compare SLV in recipient 2, we measured the total liver volume including the graft and the residual native liver as the GLV. RESULTS: The GLV/SLV at POD120 and POD360 of recipient 1 was measured 114% (1159.32 cm3 71016.95 cm3) , 97% (986.44 cm371016.95 cm3 ) with the LVRR being -11.0%, -24.3%, respectively. For recipient 2, it was measured 96% (927.32 cm3 7965.96 cm3) and 100% (968. 98 cm37965. 96 cm3 ) , with the LVRR being 24. 4% , 30. 0% , respectively. The initial graft volume of segment Ⅱ ,Ⅲ was 265.36 cm3 and increased to 335.24 cm3 and 360.56 cm3 at POD120 and POD360, respectively, with the LVRR being 26.3% and 35.9%, respectively. The GLV/SLV at POD60 of recipient 3 was 86% (893. 04 cm3/ 1038. 42 cm3 ) and the LVRR was 12. 0%. For recipient 4, it was 90% (567. 48 cm3/630. 54 cm3 ) whereas the LVRR was 20. 0%. The serum levels of ALT, AST and TB in all recipients declined gradually and returned to normal while the serum levels of PA and ALB increased to normal. The serum levels of ALT and AST peaked within 3 days after SLT. The neurological symptoms of Wilson ’s disease in recipient 2 were improved markedly. The levels of serum copper and copper-protein decreased to 30 mg/L, 120 mg/L at POD 120 and the Kayser-Fleischer rings began to obliterate. CONCLUSIONS: The size of the transplanted liver after SLT tends to converge to the standard liver volume with time and it is adequate clinically for SLT to meet the need of the body’s metabolic demands. The functional recovery of the graft liver occurs earlier than the morphological restoration.