The challenge of breath analysis for clinical diagnosis and therapeutic monitoring.

The potential of breath analysis for clinical diagnosis and the strengths and weaknesses of the analytical methods used are discussed. Special attention is given to selected ion flow tube mass spectrometry, SIFT-MS, using which on-line real-time analyses of single breath exhalations can be carried out. Illustrative data on the concentration distributions of several breath metabolites amongst the healthy population are presented and their relations to disease when elevated above the normal are alluded to.