ANALYSIS OF FECAL NEUTRAL STEROLS IN PATIENTS WITH FAMILIAL ADENOMATOUS POLYPOSIS BY GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

Previous studies have suggested that patients with familial adenomatou s polyposis (FAP) have increased faecal excretion of cholesterol but a reduction in cholesterol metabolites. It was consequently proposed th at the degree of faecal cholesterol degradation could be used as a mea ns of diagnosis. Developments in the extraction and analysis of faecal neutral sterols as well as the accurate means of diagnosing FAP by DN A analysis and indirect ophthalmoscopy has necessitated a re-examinati on of this proposal. Faecal neutral sterols were analysed in 10 patien ts with untreated FAP following a complete 5-day stool collection and compared with 9 healthy control subjects (including 4 siblings) closel y matched for age and sex. The median [25 and 75, percentiles] stool w et weights were similar between the FAP (97.5 [69, 192] g.24 h(-1)) an d the control (116 [61.5, 137] g.24 h(-1)) groups. Faecal cholesterol concentration was similar in the two groups (FAP=2.3 [1.4, 4.2]; contr ol=3.5 [1.0, 6.0] mu mol .g(-1) dry wt) as was the concentration of to tal neutral sterols not including plant sterols (FAP=17.2 [13.4, 21.0] ; control=18.2 [7.4, 21.6] mu mol.g(-1) dry wt). There were no signifi cant differences in the proportions of cholesterol metabolised between the FAP (82.3 [74.2, 93.5]%) and control(72.1 [5.7, 81.3]%) groups. T his study does not support the notion that faecal neutral sterol metab olism is uniquely different in patients with FAP.