Liver transplantation for Type I Abernethy malformation with liver tumors in children: a report of two cases with contrasting portal vein reconstruction strategies.

BACKGROUND

Type I Abernethy malformation is a rare congenital portosystemic shunt with an absent intrahepatic portal vein (PV). It often presents with liver tumors or metabolic disorders. Liver transplantation (LT) is the only definitive treatment, but it poses unique technical challenges due to the absent native PV. Detailed surgical guidance for variable anatomies remains scarce.

CASE PRESENTATION: We report two children with Type I Abernethy malformation who underwent LT in 2023. Both presented with benign liver tumors, hyperammonemia and abnormal liver function. Case 1 (2.5 y/m) received a deceased-donor left-lobe LT. Owing to insufficient PV length, a deceased-donor iliac vein graft was used for PV reconstruction. Case 2 (5.7 y/f) underwent living-donor left-lateral-sector LT with direct anastomosis of the donor left PV to the recipient's shunt vessel. Graft-to-recipient weight ratios (GRWR) were 2.29% and 1.45%, respectively.

RESULTS

Both transplant procedures were successful. Postoperative liver function and ammonia normalized. Case 2 developed hepatic venous outflow obstruction (HVOO) postoperatively, which was successfully managed with balloon angioplasty on POD 24. At 18-month follow-up, both patients were alive with good graft function, without tumor recurrence or metabolic abnormalities. To our knowledge, this is among the few reports with 18-month follow-up for pediatric patients with this disease after LT using these techniques.

CONCLUSION

This report offers a practical and anatomy-based surgical framework for PV reconstruction in pediatric Type I Abernethy malformation: direct anastomosis when an adequate shunt vessel is present, or interposition grafting (e.g., with iliac vein) when the native portal stump is absent. These contrasting strategies achieved good early outcomes at 18 months, suggesting that LT can be a curative option for this challenging anomaly. These observations are primarily hypothesis-generating. Validation will require larger, multicenter cohorts.