Serum free fatty acids and bilirubin concentration during fasting in patients with Gilbert's syndrome and normal controls

The increments in serum concentrations of unconjugated bilirubin and free fatty acids (FFA) were measured 24 and 48h after reduction of the caloric intake (400 cal/day) in 17 patients with Gilbert’s syndrome (GS) and in 12 healthy control subjects. In males, both normal and with GS, the rise in serum bilirubin was statistically higher (P<0.01) as compared to females. On the contrary, no sex difference was found in FFA concentrations. A linear correlation (p<0.01) between bilirubin and FFA serum levels was present in normal males and in patients with Gilbert’s syndrome of both sexes. Because bilirubin and FFA partly share a common, bilitranslocase-mediated, hepatic uptake mechanism, data reported support the hypothesis that a bilitranslocase function may be one of the metabolic defects in Gilbert’s syndrome.