Anomalies in hepatobiliary excretion of Technetium-99m-MAG(3) preparations

Technetium-99m-MAG(3) is accepted as a renal tubular function agent. However, sporadic liver and gall bladder visualisation during its clinical use is clearly a disadvantage. HPLC-purified (99)mTc-MAG(3) samples exhibited appreciable hepatobiliary uptake (7%), and an elevated level of such uptake was observed in unpurified kit preparations, which was stated to be associated with the excretory property of the radiolabeled kit impurities. To verify this we attempted to quantitate the hepatobiliary uptake of the kit preparations with that of its radiolabeled components. The contribution of each component toward hepatobiliary uptake of the sample was calculated from their abundance in the chelate mixture and the individual biodistribution of the isolated components. However, the anticipated hepatobiliary uptake of different preparations of Tc-99m-MAG(3) calculated in this way was always lower than that of the experimental value determined directly. Further work is needed to explain the anomaly. Copyright (C) 1996 Elsevier Science Inc.