Gas chromatography-mass spectrometry profiling of steroids in times of molecular biology.

This review's aim is to outline the potential of gas chromatography-mass spectrometry profiling of steroids in the diagnosis of endogenous human steroid disorders. Mass spectrometry currently provides the highest specificity in clinical steroid analysis. The non-invasive and non-selective GC-MS urinary steroid profiling technique enables diagnosis of almost any adrenal enzyme defects in steroid biosynthesis. While enzymatic defects can be diagnosed from spot urine samples in most cases, analysis of 24-hr urinary samples permits determination of hormonal excretion rates or enables diagnostic or therapeutic monitoring of steroid related diseases. Profiling plasma steroids by isotope dilution/GC-MS is particularly suitable where only minimal plasma samples are available and/or the highest specificity is required; therefore, GC-MS steroid profiling presents a complementary analytical technique whenever highest specificity is required. Clinical GC-MS profiling of steroids is also highly recommended as a reasonable initial diagnostic approach--especially in unclear situations--avoiding uncritical and expensive attempts at molecular diagnostic testing.