BackgroundHepatobiliary scintigraphy using 99mTc-mebrofenin has been used as an investigation to study liver function after liver transplantation (LTx). Hepatic extraction fraction (HEF) is a measurement of the hepatic extraction efficiency and hepatic extraction rate. With the purpose of evaluating a possible diverging effect of cyclosporin A (CSA) and tacrolimus (TAC) on the HEF, we compared the HEF with biochemical and histological parameters in LTx patients receiving either CSA or TAC.MethodsThirty-nine adult patients who underwent LTx due to hepatitis C virus (HCV) cirrhosis were evaluated. All patients underwent a 3-month and 1-year follow-up that included hepatobiliary scintigraphy and biochemistry tests. Liver biopsy was performed at 1 year. These clinical parameters were compared between the two groups, TAC (n = 15) and CSA (n = 24).ResultsThe average HEF was significantly lower in the CSA group compared to the TAC group both at 3 months and 1 year after LTx. The liver biochemistry tests, average donor and recipient age, average cold ischemia time (CIT), and a clearance were comparable in the two groups. The TAC group had more inflammation than the CSA group. Moreover, three patients who converted from CSA to TAC increased their HEF values.ConclusionsCSA-treated patients presented a lower HEF value on hepatobiliary scintigraphy in spite of comparable liver function by traditional measurements indicating a decrease on HEF values by CSA.