Systematic laboratory diagnosis of human metabolic disorders

A multicomponent analytical system for diagnosis of human metabolic disorders is overviewed. After preliminary analysis of the urine with simple chemical tests and standard clinical chemistry methods, the samples undergo a variety of chromatographic separations. Paper chromatography and thin-layer chromatography determine carbohydrates and mucopolysaccharides. Amino acids are analysed by automatic ionexchange chromatography. Gas chromatography - mass spectrometry with computerized library search is used to separate and identify organic acids, and high performance liquid chromatography with computerized diodearray detector is used to analyse metabolites of nucleic acids and other non-volatile or labile constituents. The system, gradually developed during the past two decades, is routinely used to diagnose, via its detection of pathological metabolites, around 100 different metabolic disorders. The methods may also be used to monitor the efficacy of therapeutic treatment in some of the cases where this is possible.