99m Tc-HEPIDA hepatic clearance as a diagnostic tool: usefulness of plasma and hepatic clearance for assessment of hepatic parenchyma performance

摘要

Plasma clearance of 99m Tc-HEPIDA (Cl Pl ) has been used for two decades for assessment of liver function in patients with diseases of this organ. A specific determination of 99m Tc-HEPIDA liver clearance (Cl Hp ) has been developed that provides more direct possibility to evaluate performance of liver parenchyma. Both tests have been studied in healthy volunteers of varying age (48 individuals) and in 83 patients with varying degree of liver damage. The liver damage has been evaluated on the basis of 5 biochemical tests (AspAT, ALAT, GGTP, bilirubine serum concentration, proteinogram) and a score system used for total impairment, which was calculated for each patient. Normal range of Cl Pl and Cl Hp was determined from a study on healthy individuals (volunteers). The results seem independent of age, but show sex differences. The following values (mean ± SD) of Cl Hp were found in males and females of: (181 ± 31) ml//min/1.73 m 2 and (158 ± 22) ml/min/1.73m 2 , and of Cl Pl were (224 ± 33) ml/min/1.73 m 2 and (202 ± 25) ml/min/1.73 m 2 respectively. Accepted lower boundaries of both quantities (mean –2SD) are 115 ml/min/1.73 m 2 and 150 ml/min/1.73 m 2 correspondingly. Negative correlation of individual values of both clearances in all patients with individual score of liver damage were highly significant and correlation coefficients obtained were higher for Cl Hp (r = –0.63) than those for Cl Pl (r= –0.56). Factorial analysis was performed with the intention of seeing which of the studied factors had the highest factor loading for parenchyma performance that was assumed as the common factor responsible for correlations. The highest value was obtained for hepatic clearance (Cl Hp ) of 99m Tc-HEPIDA. In conclusion this quantity seems highly promising as a clinically useful test for assessment of liver performance, both in screening for liver damage and for monitoring of organ conditions during therapy and follow-up of patients.