Chemometric study and analytical enzymatic methods for diagnosis of cholesterol gallstones.

The lithogenic index (IL) provides an estimate of cholesterol saturation in gallbladder bile and is of possible value for prediction of gallstone formation. A package for pattern recognition of analytical chemical data, known as "Parvus", was used to study the different values of IL obtained experimentally using common enzymic methods for cholesterol and bile salts and other analytical techniques for phospholipids. Ten patients were investigated and some interesting conclusions were drawn, both on the equivalence of various analytical methods for the determination of phospholipids and on the contribution of pattern recognition analysis to the diagnosis of gallstones.