Delta and conjugated bilirubin as complementary markers of early rejection in liver-transplant recipients

For 51 liver allograft recipients, we evaluated whether serum profiles of delta (Bd) and conjugated bilirubine (Bc) could be used to diagnose rejection during the first 30-50 postoperative days, in comparison with histology as the "gold standard." Daily measurements of aspartate aminotransferase, alkaline phosphatase, total bilirubin, Bd, and Bc were made, the last two by liquid chromatography. In 34 patients without any biochemical or histological evidence of rejection, within seven to 10 postoperative days Bd increased to >40-50% of total bilirubin, while Bc decreased to <10%. In patients with severe rejections resulting in death, Bc increased rapidly to >50%, while Bd remained <30%. In 24 histologically proven episodes of rejection in 17 patients there was either a rapid decrease in Bd or its persistence at 30%, plus either a steep increase in Bc, or its remaining at >50% total bilirubin. Treatment of rejection resulted in a prompt reversal of these trends. Individually promising as prognostic adjuncts to existing liver-function markers, Bd and Bc also complemented each other, rendering the diagnosis of liver rejection much more incisive.