We carried out a retrospective study of 71 patients with congenital non-hemolytic
hyperbilirubinemia who had been treated at our institution over the 25 years from 1965 to 1990. Twenty patients had
Gilbert's syndrome, 1 had
Crigler-Najjar syndrome, 1 had new type unconjugated
hyperbilirubinemia, 21 had
Dubin-Johnson syndrome, and 28 had Rotor's syndrome. We also reviewed 20 patients with constitutional
indocyanine green (ICG) excretory defect. The study focused on the hepatic transport of serum
bilirubin, bromsulfophthalein (BSP), and ICG. In
Dubin-Johnson syndrome, a defect appeared in late-stage transport, while uptake and storage capacity were normal. In Rotor's syndrome, defects were found in the early stage, and storage capacity was reduced, while excretion into bile was slightly suppressed. A secondary rise in serum ICG was seen in 5 of the 10 patients with
Dubin-Johnson syndrome. The transport defect in
Gilbert's syndrome was unclear. It could not be considered to be homogeneous, but it may exist at multiple sites, from the conjugation with
serum proteins to excretion into bile. Following
phenobarbital administration, the ICG secondary rise in the 5 patients with
Dubin-Johnson syndrome disappeared, and ICG was rapidly cleared from blood. However, in patients with
Dubin-Johnson syndrome, BSP clearance in serum did not show any change before and after
phenobarbital administration. ICG excretion in patients with constitutional ICG excretory defect was due only to the impairment o ICG transport, and the defect was suggested to be hepatic uptake. These results indicate that studies of the hepatic transport of
bilirubin, BSP, and ICG are useful for determining the etiological factors involved in congenital
hyperbilirubinemia and constitutional ICG excretory defect.