Sedimentation of biliary sludge: effect on composition of gallbladder bile from patients with cholesterol, mixed, or pigment stones.
BACKGROUND
Ultracentrifugation of bile has been used extensively to remove insoluble material such as sludge from bile before further studies of cholesterol nucleation. Although it has been recognized that this procedure may affect the composition of gallbladder bile, it has not been studied systematically in different gallstone populations. Therefore, we investigated the concentration of biliary lipids, protein, mucin, and bilirubin before and after ultracentrifugation.


METHODS
Gallbladder bile samples were aspirated during laparoscopic surgery from 66 patients (35 with cholesterol, 16 with mixed, and 15 with pigment stones).


RESULTS
Whereas the concentrations of bile acids, phospholipids, protein, and bilirubin in gallbladder bile did not change significantly after ultracentrifugation, cholesterol (20.6 +/- 1.6 to 14.8 +/- 1.2 mmol/l) and mucin concentrations (0.99 +/- 0.2 to 0.67 +/- 0.1 mg/ml) and the cholesterol saturation index (1.68 +/- 0.12 to 1.31 +/- 0.10) decreased significantly in gallbladder bile from patients with cholesterol stones.


CONCLUSIONS
Sedimentation of biliary sludge may profoundly affect the composition of gallbladder bile, which has to be considered in studies of cholesterol saturation and nucleation. The cholesterol concentration difference between native and ultracentrifuged bile reflects the insoluble crystalline fraction of cholesterol and may be useful for quantitation of the mass of cholesterol crystals in gallstone-associated bile samples.
Jungst
D
D
Depts. of Medicine II, Ludwig-Maximilians University Munich, Germany.
Del Pozo
R
R
Christoph
S
S
Miquel
J F
JF
Eder
M I
MI
Lange
V
V
Frimberger
E
E
Von Ritter
C
C
Paumgartner
G
G
D001646:Bile / Q000737:chemistry*; D001647:Bile Acids and Salts / Q000032:analysis; D001654:Bile Pigments / Q000032:analysis; D001663:Bilirubin / Q000032:analysis; D002769:Cholelithiasis / Q000737:chemistry*; D002784:Cholesterol / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D009077:Mucins / Q000032:analysis; D010743:Phospholipids / Q000032:analysis; D011506:Proteins / Q000032:analysis; D014461:Ultracentrifugation
D001647:Bile Acids and Salts; D001654:Bile Pigments; D009077:Mucins; D010743:Phospholipids; D011506:Proteins; D002784:Cholesterol; D001663:Bilirubin