Glucuronidation of bilirubin and the occurrence of pigment gallstones in patients with chronic haemolytic diseases

Abstract

A group of 37 patients with increased heme catabolism was studied to gain insight into their bilirubin conjugating capacity. Bilirubin UDP-glucuronyl transferase activity (GlcATa) in the liver and bilirubin monoconjugates in bile were measured and the hepatic bilirubin clearance was calculated from the radio-Cr-survival data. In the present group, 41% of the patients clearly had a deficiency in bilirubin conjugation similar to what is classically found in Gilbert''s syndrome. The association may facilitate detection of these patients as serum bilirubin levels were higher (65.8 .mu.M .+-. 19) (m .+-. 1 SD) in the 15 patients with associated Gilbert''s syndrome vs. 13 having only hemolysis (43.6 .mu.M .+-. 15). A fair correlation was found between the percentage of monoconjugates in bile and the GlcATa levels in the liver as well as with the calculated hepatic bilirubin clearance, although some discrepancies exist. Using these determinations, a clearcut separation from normal values was not obtained, suggesting at least in the present group of patients that Gilbert''s syndrome represents only one end of a continuum of bilirubin conjugation rates and not a separate entity. Pigment stones in the gallbladder were documented in 51% of the patients and usually at an early age. There was no relationship to sex, serum bilirubin, GlcATa in liver, total bilirubin or monoconjugates in bile. Age played some role as well as the type of hemolysis, as all patients with congenital dyserythropoiesis (n = 4) or acquired hemolysis (n = 3) had lithiasis. Moderate chronic cholecystitis was present, whereas an accumulation of iron and bile pigment was evident in the liver.