The identification of urinary bile alcohols by gas chromatography–mass spectrometry in patients with liver disease and in healthy individuals

Abstract. The neutral steroid fractions in the urine of eleven patients suffering from various forms of liver disease with cholestasis and of ten healthy individuals were studied by glass capillary gas chromatography-mass spectrometry. The steroid conjugates in urine were enzymatically solvolysed, the liberated steroids extracted and transformed into the trimethylsilylether for measurements.
The excretion rates of androstane and pregnane metabolites of patients with liver disease were far lower than those of healthy persons. The main compounds in the urine of the former were the bile alcohols 27 - nor -3α, 7α, 12α, 24, 25 - pentahydroxy - 5β - cholestane and 3α, 7α, 12α, 25, 26 - pentahydroxy - 5β - cholestane. Our data suggest a correlation between the excretion rates of these bile alcohols and the serum levels of bilirubin. While the excretion rate of the two bile alcohols in the urine of healthy individuals was approximately 0.24 mg/24 h (0.6 μmol/24 h) a patient with a serum bilirubin of 841 μmol/1 excreted 4 mg/24 h (9 μmol/24 h). The accumulation of bile alcohols described in this study possibly indicates alternative pathways of cholic acid formation in liver disease.