CHOLESTEROL SATURATION, NOT PROTEINS OR CHOLECYSTITIS, IS CRITICAL FOR CRYSTAL-FORMATION IN HUMAN GALLBLADDER BILE

Background & Aims: Biliary proteins are promoters of cholesterol cryst allization in artificial model bile. However, their pathogenic importa nce for cholesterol precipitation in native gallbladder bile (GB) is u ncertain. The aim of this study was to evaluate the significance of bi liary lipids and proteins on cholesterol crystal detection time (ChCDT ) of GB in patients with gallstones. Methods: ChCDT and concentrations of lipids, albumin, mucins, aminopeptidase N, alpha 1-acid glycoprote in, haptoglobin, and immunoglobulins (Igs) were measured in GB of 92 p atients, 52 of whom had cholesterol gallstones. Results: ChCDT was mar kedly reduced in gallstone patients. Compared with patients without ga llstones, they had a significant increase in cholesterol saturation an d total protein, albumin, mucin, and IgG biliary concentrations. In un ivariate analysis, ChCDT of GB was significantly correlated with chole sterol saturation and total lipid, protein, Ig, aminopeptidase N, and alpha 1-acid glycoprotein concentrations. However, stepwise logistic r egression analysis showed that only cholesterol saturation independent ly correlated to ChCDT. Gallbladder inflammation correlated with the c oncentration of Igs, but subtraction of IgG from GB did not modify the ChCDT. Conclusions: Biliary cholesterol transport and saturation, but not proteins, appear critical for the cholesterol crystallization abn ormality observed in native bile from patients with gallstones.