Living donor liver transplantation allows patients with end-stage liver disease the opportunity for treatment, in the face of a critical shortage of cadaveric organs.
However, hepatic steatosis decreases functional graft mass and may contribute to graft dysfunction.
Screening liver biopsy allows an accurate measure of hepatic fat, but is an invasive procedure that is not universally employed in the evaluation of living donors.
|BMI correlated only weakly with biopsy.|
In this study, a research team from Rochester, New York, studied 100 consecutive prospective right lobe living donors.
All prospective donors were evaluated using liver biopsy, imaging studies, and various clinical parameters.
The team then compared body mass index (BMI) and imaging with biopsy, to determine their accuracy in determining the amount of hepatic fat.
The researchers found no complications to biopsy, with 33% showing some degree of steatosis.
However, they also found that BMI correlated weakly with biopsy, with 73% of overweight (BMI > 25) donors having little or no hepatic fat.
Furthermore, imaging was only 12% sensitive to small amounts of fat, with increasing sensitivity to more severe steatosis.
In addition, imaging diagnosed steatosis in 2 donors without hepatic fat and failed to identify a candidate denied with biopsy-proven 30% steatosis.
Conversely, 9% of candidates with BMIs of 25 or less had 10% or greater steatosis, while 3 candidates were denied surgery because biopsy detected occult liver disease.
Dr Charlotte Ryan's team concluded, "Accurate quantification of hepatic fat is not afforded by BMI and imaging studies alone".
"Screening liver biopsy has a low complication rate and may serve to increase donor safety".
"Biopsy is essential in identifying donor grafts at risk for poor recipient outcome while maximizing the donor pool".
In a related article in the same publication, Drs Mary Rinella and Michael Abecassis, from Chicago, Illinios, debate the issues involved in selecting suitable liver donors.
They discuss the issues raised in the above article, concluding that, "Potential candidates who are obese should undergo hepatic tissue sampling".
However, "Liver biopsy is one of many diagnostic tools used to evaluate potential donors and should be used judiciously, weighing all other data available".