Hepatic steatosis in organ donors: disparity between surgery and histology?

In times of organ shortage, use of marginal cadaveric livers has become increasingly important to reduce pressing organ demand and rising death rates while awaiting donations. Indisputably, fatty change in donor livers is a risk factor for poor initial function after orthotopic transplantation. However, identifying and rejecting marginal from good donor livers is one of the most difficult surgical tasks. Unfortunately, a liver biopsy with rapid histological diagnosis is rarely performed to identify marginal livers.

From 2005 to 2008, we investigated 36 livers of organ donors, which were explanted but not transplanted or underwent liver wedge biopsy during organ donation. All livers underwent standard surgical procedures and were allocated by Eurotransplant International Foundation. After unsuccessful allocation, explanted livers were photographically documented, formalin-fixed, and analyzed histopathologically.

Seven livers were classified as good organ quality by the surgeon (19.4%); 15 were acceptable (41.6%); and 14 poor (39%). In 63.8% of livers, a frozen section was performed; 6/36 cases (16.7%) showed macrovesicular and microvesicular steatosis of less than 30%. In addition, all six cases fulfilled two or less extended donor criteria, as defined by the German Medical Association.

More marginal livers from cadaveric organ donors could have been transplanted. To extend the transplant pool of liver grafts, liver biopsies should be performed in all cases of acceptable and poor livers. If frozen section analysis is performed, a wedge liver biopsy should be taken from at least two different segments of the liver to validate the histological results.