Abstract
A 27 year-old male with mild obesity was admitted for evaluation of slight abnormality in serum total bilirubin and serum transaminase activity. There was marked discrepancy between ICG clearance and bromsulphthalein (BSP) clearance rate: ICG R15 was 79.5%, KICG was 0.026 and BSP R15 was 3%. The transfer rate constants of ICG showed decreases in all of three components (a: the rate of leaving the plasma to enter the liver, b: the rate of passing back from the liver to the plasma, h: the rate of passing back from the liver to the bile), especially in a component. In this patient, a component was not changed but b component was clearly increased following the increase in ICG loading dose, while both components were clearly decreased in normal controls. The maximal removal rate of ICG (ICG R max) showed a marked decrease. Ultrastructural study of his hepatic biopsy showed that the smooth and rough endoplasmic reticulum of the hepatocytes was vesiculated, and in the enlarged cisterna of these organelles slight electron dense particles were observed, suggesting disturbance in intraccllular transport of ICG carring substances. By his familiar study, one of sisters showed prominent ICG clearance abnormality and the other sister showed slightly abnormal clearance of ICG. These findings suggested that the defect of ICG excretory mechanism could be due to, at least in part, a decrease in saturating index of receptor-carrier protein for ICG of hepatocytes and disturbance in intracellular transport of ICG.
